Technical Reports
NASA — National Aeronautics and Space Administration · 2,169 documents.
- [Tail Plane Icing]The Aviation Safety Program initiated by NASA in 1997 has put greater emphasis in safety related research activities. Ice-contaminated-tailplane stall (ICTS) has been identified by the NASA Lewis Icing Technology Branch as an important activity for aircraft safety related research. The ICTS…16 pp19990026834
- 367-80 airplane variable stability simulation system /NASA Langley supersonic transport simulation program/Four-engine jet aircraft used as in-flight simulator for variable stability testing of supersonic aircraft215 ppNASA-CR-66126
- 9- by 15-Foot Low Speed Wind Tunnel Acoustic Improvements Expanded OverviewThe 9- by 15-Foot Low Speed Wind Tunnel (9x15 LSWT) at NASA Glenn Research Center was built in 1969 in the return leg of the 8- by 6-Foot Supersonic Wind Tunnel (8x6 SWT). The 8x6 SWT was completed in 1949 and acoustically treated to mitigate community noise issues in 1950. This treatment included…35 ppGRC-E-DAA-TN31946
- 9- by 15-Foot Low-Speed Wind Tunnel Commissioning Test Using Advanced Ducted PropulsorA subscale model of an aircraft engine fan was tested in the 9- by 15-Foot Low-Speed Wind Tunnel at the NASA Glenn Research Center in 2022. The fan model was the Advanced Ducted Propulsor Fan 1 designed by Pratt & Whitney in the 1990s. It has been part of multiple wind tunnel test campaigns over…34 ppNASA/TM-20250004035
- 9x15 Low Speed Wind Tunnel Acoustic ImprovementsThe 9- by 15-Foot Low Speed Wind Tunnel (9x15 LSWT) at NASA Glenn Research Center was built in 1969 in the return leg of the 8- by 6-Foot Supersonic Wind Tunnel (8x6 SWT). The 8x6 SWT was completed in 1949 and acoustically treated to mitigate community noise issues in 1950. This treatment included…18 ppGRC-E-DAA-TN31484
- 9x15 Low Speed Wind Tunnel Improvement Update and PlansThe 9- by 15-Foot Low Speed Wind Tunnel (9x15 LSWT) at NASA Glenn Research Center was built in 1969 in the return leg of the 8- by 6-Foot Supersonic Wind Tunnel (8x6 SWT). The 8x6 SWT was completed in 1949 and acoustically treated to mitigate community noise issues in 1950. This treatment included…19 ppGRC-E-DAA-TN67410
- 9x15 Low Speed Wind Tunnel Improvements UpdateThe 9- by 15-Foot Low Speed Wind Tunnel (9x15 LSWT) at NASA Glenn Research Center was built in 1969 in the return leg of the 8- by 6-Foot Supersonic Wind Tunnel (8x6 SWT). The 9x15 LSWT was designed for performance testing of VSTOL aircraft models, but with the addition of the current acoustic…18 pp20170006618
- A 150 and 300 kW lightweight diesel aircraft engine design studyThe diesel engine was reinvestigated as an aircraft powerplant through design study conducted to arrive at engine configurations and applicable advanced technologies. Two engines are discussed, a 300 kW six-cylinder engine for twin engine general aviation aircraft and a 150 kW four-cylinder engine…150 pp19800011788
- A Base Drag Reduction Experiment on the X-33 Linear Aerospike SR-71 Experiment (LASRE) Flight ProgramDrag reduction tests were conducted on the LASRE/X-33 flight experiment. The LASRE experiment is a flight test of a roughly 20% scale model of an X-33 forebody with a single aerospike engine at the rear. The experiment apparatus is mounted on top of an SR-71 aircraft. This paper suggests a method…21 pp19990026605
- A brief review of aircraft controls research opportunities in the general aviation fieldA review of aircraft controls research in the general aviation field is given. Among the topics included are: controls technology benefits, military and commercial test programs, flight tests, ride quality control, and wind loading.18 pp19840012527
- A Comparative Study of Simulated and Measured Gear-Flap Flow InteractionThe ability of two CFD solvers to accurately characterize the transient, complex, interacting flowfield asso-ciated with a realistic gear-flap configuration is assessed via comparison of simulated flow with experimental measurements. The simulated results, obtained with NASA's FUN3D and Exa's…22 pp20160006000
- A Comparative Study of Simulated and Measured Main Landing Gear Noise for Large Civil TransportsComputational results for the NASA 26%-scale model of a six-wheel main landing gear with and without a toboggan-shaped noise reduction fairing are presented. The model is a high-fidelity representation of a Boeing 777-200 aircraft main landing gear. A lattice Boltzmann method was used to simulate…19 ppNF1676L-25839
- A comparison of the V/STOL handling qualities of the VAK-191B with the requirements of AGARD report 577 and MIL-F-83300The handling qualities of the VAK-191B VTOL aircraft are compared with current V/STOL handling qualities requirements. The aircraft handling qualities were superior to other V/STOL fighter aircraft. Several deficiencies which would seriously affect shipboard V/STOL operation includes: (1) poor…39 pp19790019011
- A compilation and analysis of helicopter handling qualities data. Volume 2: Data analysisA compilation and an analysis of helicopter handling qualities data are presented. Multiloop manual control methods are used to analyze the descriptive data, stability derivatives, and transfer functions for a six degrees of freedom, quasi static model. A compensatory loop structure is applied to…186 pp19790023051
- A concept for a fuel efficient flight planning aid for general aviationA core equation for estimation of fuel burn from path profile data was developed. This equation was used as a necessary ingredient in a dynamic program to define a fuel efficient flight path. The resultant algorithm is oriented toward use by general aviation. The pilot provides a description of the…96 pp19820011343
- A corporate supersonic transportThis talk address the market and technology for a corporate supersonic transport. It describes a candidate configuration. There seems to be a sufficient market for such an aircraft, even if restricted to supersonic operation over water. The candidate configuration's sonic boom overpressure may be…24 pp
- A critical assessment of wind tunnel results for the NACA 0012 airfoilA large body of experimental results, obtained in more than 40 wind tunnels on a single, well-known two-dimensional configuration, has been critically examined and correlated. An assessment of some of the possible sources of error has been made for each facility, and data which are suspect have…23 ppNASA-TM-100019
- A design procedure for the handling qualities optimization of the X-29A aircraftA design technique for handling qualities improvement was developed for the X-29A aircraft. As with any new aircraft, the X-29A control law designers were presented with a relatively high degree of uncertainty in their mathematical models. The presence of uncertainties, and the high level of static…28 ppNASA-TM-4142
- A Discussion of the Last Flight of X-31A Aircraft No.1This presentation covers the preparation and conduct of the final flight of X-31A aircraft #1 and the lessons learned as applied to flight test of research vehicles.22 pp20110014438
- A Dynamic Model for the Evaluation of Aircraft Engine Icing Detection and Control-Based Mitigation StrategiesAircraft flying in regions of high ice crystal concentrations are susceptible to the buildup of ice within the compression system of their gas turbine engines. This ice buildup can restrict engine airflow and cause an uncommanded loss of thrust, also known as engine rollback, which poses a…17 ppGRC-E-DAA-TN43977
- A Dynamic Model for the Evaluation of Aircraft Engine Icing Detection and Control-Based Mitigation StrategiesAircraft flying in regions of high ice crystal concentrations are susceptible to the buildup of ice within the compression system of their gas turbine engines. This ice buildup can restrict engine airflow and cause an uncommanded loss of thrust, also known as engine rollback, which poses a…13 ppGRC-E-DAA-TN39681
- A feasibility study for advanced technology integration for general aviationAn investigation was conducted to identify candidate technologies and specific developments which offer greatest promise for improving safety, fuel efficiency, performance, and utility of general aviation airplanes. Interviews were conducted with general aviation airframe and systems manufacturers…526 ppNASA-CR-159381
- A Feasibility Study on the Control of a Generic Air Vehicle Using Control Moment GyrosThis paper examines feasibility and performance issues in using Control Moment Gyroscopes (CMGs) to control the attitude of a fixed-wing aircraft. The paper describes a control system structure that permits allocating control authority and bandwidth between a CMG system and conventional aerodynamic…13 ppAIAA Paper 2006-6313
- A flight and simulator study of the handling qualities of a deflected slipstream stol sea- plane having four propellers and boundary- layer controlFlight and simulator study of handling qualities of deflected slipstream STOL seaplane having four propellers and boundary layer control45 pp19650023751
- A flight and wind tunnel investigation of the effect of angle-of-attack rate on maximum lift coefficientWind tunnel tests to determine effect of angle of attack on maximum lift at stall for half-wing models, and single engine, jet propelled aircraft57 ppNASA-CR-321
- A Flight Investigation of the Low-Speed Handling Qualities of a Tailless Delta-Wing Fighter AirplaneCarrier landing-approach studies of a tailless delta-wing fighter airplane disclosed that approach speeds were limited by ability to control altitude and lateral-directional characteristics. More detailed flight studies of the handling-qualities characteristics of the airplane in the…36 pp19980232080
- A flight investigation of the stability, control, and handling qualities of an augmented jet flap STOL airplaneThe stability, control, and handling qualities of an augmented jet flap STOL airplane are presented. The airplane is an extensively modified de Havilland Buffalo military transport. The modified airplane has two fan-jet engines which provide vectorable thrust and compressed air for the augmentor…151 pp19780018208
- A Flight Investigation of the STOL Characteristics of an Augmented Jet Flap STOL Research AircraftThe flight test program objectives are: (1) To determine the in-flight aerodynamic, performance, and handling qualities of a jet STOL aircraft incorporating the augmented jet flap concept; (2) to compare the results obtained in flight with characteristics predicted from wind tunnel and simulator…143 pp19740014524
- A fuel conservation study for transport aircraft utilizing advanced technology and hydrogen fuelThe conservation of fossil fuels in commercial aviation was investigated. Four categories of aircraft were selected for investigation: (1) conventional, medium range, low take-off gross weight; (2) conventional, long range, high take-off gross weights; (3) large take-off gross weight aircraft that…33 pp19730002292
- A fuel-efficient cruise performance model for general aviation piston engine airplanesA fuel-efficient cruise performance model which facilitates maximizing the specific range of General Aviation airplanes powered by spark-ignition piston engines and propellers is presented. Airplanes of fixed design only are considered. The uses and limitations of typical Pilot Operating Handbook…399 pp19830025620
- A Fully Non-metallic Gas Turbine Engine Enabled by Additive ManufacturingThe Non-Metallic Gas Turbine Engine project, funded by NASA Aeronautics Research Institute (NARI), represents the first comprehensive evaluation of emerging materials and manufacturing technologies that will enable fully nonmetallic gas turbine engines. This will be achieved by assessing the…21 ppGRC-E-DAA-TN17465
- A Fully Non-Metallic Gas Turbine Engine Enabled by Additive ManufacturingIn a NASA Aeronautics Research Institute (NARI) sponsored program entitled "A Fully Non-Metallic Gas Turbine Engine Enabled by Additive Manufacturing," evaluation of emerging materials and additive manufacturing technologies was carried out. These technologies may enable fully non-metallic gas…21 ppGRC-E-DAA-TN25404
- A Fully Non-Metallic Gas Turbine Engine Enabled by Additive ManufacturingIn a NASA Aeronautics Research Institute (NARI) sponsored program entitled "A Fully Non-Metallic Gas Turbine Engine Enabled by Additive Manufacturing", evaluation of emerging materials and additive manufacturing technologies was carried out. These technologies may enable fully non-metallic gas…9 ppISABE-2015-20168
- A Fully Non-Metallic Gas Turbine Engine Enabled by Additive ManufacturingThe Non-Metallic Gas Turbine Engine project, funded by NASA Aeronautics Research Institute, represents the first comprehensive evaluation of emerging materials and manufacturing technologies that will enable fully nonmetallic gas turbine engines. This will be achieved by assessing the feasibility…30 ppGRC-E-DAA-TN20441
- A Fully Non-Metallic Gas Turbine Engine Enabled by Additive Manufacturing Part I: System Analysis, Component Identification, Additive Manufacturing, and Testing of Polymer CompositesThe research and development activities reported in this publication were carried out under NASA Aeronautics Research Institute (NARI) funded project entitled "A Fully Nonmetallic Gas Turbine Engine Enabled by Additive Manufacturing." The objective of the project was to conduct evaluation of…24 ppNASA/TM-2015-218748
- A Future with Hybrid Electric Propulsion Systems: A NASA PerspectiveThe presentation highlights a NASA perspective on Hybrid Electric Propulsion Systems for aeronautical applications. Discussed are results from NASA Advance Concepts Study for Aircraft Entering service in 2030 and beyond and the potential use of hybrid electric propulsion systems as a potential…21 pp20150000748
- A Generic Guidance and Control Structure for Six-Degree-of-Freedom Conceptual Aircraft DesignA control system framework is presented for both real-time and batch six-degree-of-freedom simulation. This framework allows stabilization and control with multiple command options, from body rate control to waypoint guidance. Also, pilot commands can be used to operate the simulation in a…26 ppNASA/TM-2005-212866
- A Guide to Forced Oscillation Data Processing and AnalysisThe NASA Langley Research Center Flight Dynamics Branch has a long history of experimental testing of aircraft and spacecraft flight dynamics. One of the frequently used wind tunnel test methods is forced oscillation testing. This method involves a model mounted on a specialized dynamic test rig in…34 pp
- A Landing Gear Noise Reduction Study Based on Computational SimulationsLanding gear is one of the more prominent airframe noise sources. Techniques that diminish gear noise and suppress its radiation to the ground are highly desirable. Using a hybrid computational approach, this paper investigates the noise reduction potential of devices added to a simplified main…11 pp
- A Learn-to-Fly Approach for Adaptively Tuning Flight Control SystemsA method is presented for adaptively tuning feedback control gains in a flight control system to achieve desired closed-loop performance. The method combines efficient aircraft parameter estimation, for identifying closed-loop dynamics models, with online nonlinear optimization, for sequentially…22 pp
- A Learn-to-Fly Approach for Adaptively Tuning Flight Control SystemsA method is presented for adaptively tuning feedback control gains in a flight control system to achieve desired closed-loop performance. The method combines efficient aircraft parameter estimation, for identifying closed-loop dynamics models, with online nonlinear optimization, for sequentially…23 ppNF1676L-35663
- A Look at Handling Qualities of Canard ConfigurationsThe first human-powered flight was achieved by a canard-configured aircraft (Wright Brothers). Although other canard concepts were flown with varying degrees of success over the years, the tail-aft configuration has dominated the aircraft market for both military and civil use. Reviewed are the…49 pp19870013196
- A Mathematical Model for Vertical Attitude Takeoff and Landing (VATOL) Aircraft Simulation: Model Description Application - Volume 1A mathematical model of a high performance airplane capable of vertical attitude takeoff and landing (VATOL) was developed. An off line digital simulation program incorporating this model was developed to provide trim conditions and dynamic check runs for the piloted simulation studies and support…228 pp19810019546
- A mathematical model for Vertical Attitude Takeoff and Landing (VATOL) aircraft simulation. Volume 3: User's manual for VATOL simulation programInstructions for using Vertical Attitude Takeoff and Landing Aircraft Simulation (VATLAS), the digital simulation program for application to vertical attitude takeoff and landing (VATOL) aircraft developed for installation on the NASA Ames CDC 7600 computer system are described. The framework for…428 pp19810019548
- A mathematical model of an active control landing gear for load control during impact and roll-outA mathematical model of an active control landing gear (ACOLAG) was developed and programmed for operation on a digital computer. The mathematical model includes theoretical subsonic aerodynamics; first-mode wing bending and torsional characteristics; oleo-pneumatic shock strut with fit and binding…73 ppNASA-TN-D-8080
- A method for analyzing the aeroelastic stability of a helicopter rotor in forward flightAerodynamic stability of helicopter rotor in forward flight111 ppNASA-CR-1332
- A method for landing gear modeling and simulation with experimental validationThis document presents an approach for modeling and simulating landing gear systems. Specifically, a nonlinear model of an A-6 Intruder Main Gear is developed, simulated, and validated against static and dynamic test data. This model includes nonlinear effects such as a polytropic gas model,…100 ppNASA-CR-201601
- A method to estimate weight and dimensions of small aircraft propulsion gas turbine engines: User's guideThe weight and major envelope dimensions of small aircraft propulsion gas turbine engines are estimated. The computerized method, called WATE-S (Weight Analysis of Turbine Engines-Small) is a derivative of the WATE-2 computer code. WATE-S determines the weight of each major component in the engine…136 pp19830008072
- A Mission-Adaptive Variable Camber Flap Control System to Optimize High Lift and Cruise Lift-to-Drag Ratios of Future N+3 Transport AircraftBoeing and NASA are conducting a joint study program to design a wing flap system that will provide mission-adaptive lift and drag performance for future transport aircraft having light-weight, flexible wings. This Variable Camber Continuous Trailing Edge Flap (VCCTEF) system offers a…24 pp20140006948
- A NASA Approach to Safety Considerations for Electric Propulsion Aircraft TestbedsElectric, hybrid-electric, and turbo-electric distributed propulsion technologies and concepts are beginning to gain traction in the aircraft design community, as they can provide improvements in operating costs, noise, fuel consumption, and emissions compared to conventional internal combustion or…12 pp20170006610
- A neural based intelligent flight control system for the NASA F-15 flight research aircraftA flight control concept that can identify aircraft stability properties and continually optimize the aircraft flying qualities has been developed by McDonnell Aircraft Company under a contract with the NASA-Dryden Flight Research Facility. This flight concept, termed the Intelligent Flight Control…4 pp
- A Parametric Study of Actuator Requirements for Active Turbine Tip Clearance Control of a Modern High Bypass Turbofan EngineThe efficiency of aircraft gas turbine engines is sensitive to the distance between the tips of its turbine blades and its shroud, which serves as its containment structure. Maintaining tighter clearance between these components has been shown to increase turbine efficiency, increase fuel…15 pp20170008736
- A performance application study of a jet-flap helicopter rotorA performance study was made of the application of a jet-flap to a reaction-drive rotor for a heavy-lift helicopter mission and for a high-speed-helicopter maneuverability (200 knots, 2g) mission. The results of the study are as follows: As a result of the increase in maximum airfoil lift…95 ppNASA-CR-112030
- A Perspective of Computational Aeroelasticity 1970s to NowTo present a summary of frequency domain and time domain procedures for aeroelasticity by using non-linear flow equations80 pp20180007396
- A pertinent solution of helicopter rotor flapping stabilityThe stability of the flapping motion of a single blade of a helicopter rotor is examined using the techniques of perturbation theory. The equation of motion studied is linear, with periodic aerodynamic coefficients due to the forward speed of the rotor. Solutions are found for four cases: small and…123 ppNASA-TM-X-62165
- A Piecewise Linear State Variable Technique for Real Time Propulsion System SimulationThe emphasis on increased aircraft and propulsion control system integration and piloted simulation has created a need for higher fidelity real time dynamic propulsion models. A real time propulsion system modeling technique which satisfies this need and which provides the capabilities needed to…15 pp19820016325
- A pilot's assessment of helicopter handling-quality factors common to both agility and instrument flying tasksA series of simulation and flight investigations were undertaken to evaluate helicopter flying qualities and the effects of control system augmentation for nap-of-the-Earth (NOE) agility and instrument flying tasks. Handling quality factors common to both tasks were identified. Precise attitude…21 pp19800019840
- A piloted simulator study of takeoff performance and handling qualities of a double delta supersonic transportSimulated flight test of double-Delta supersonic transport for performance characteristics, handling qualities, and climbing characteristics51 pp19680007922
- A Plan for Revolutionary Change in Gas Turbine Engine Control System ArchitectureThe implementation of Distributed Engine Control technology on the gas turbine engine has been a vexing challenge for the controls community. A successful implementation requires the resolution of multiple technical issues in areas such as network communications, power distribution, and system…34 ppE-17833
- A preliminary comparison between the SR-6 propeller noise in flight and in a wind tunnelHigh speed turboprops offer an attractive candidate for aircraft because of their high propulsive efficiency. However, one of the possible problems associated with these propellers is their high noise level at cruise condition that may create a cabin environment problem. Models of these propellers…19 ppNASA-TM-83341
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- A Preliminary Evaluation of Icing Scaling on AAM PropellersNASA Glenn Research Center recently developed a general-purpose propeller test stand for conducting fundamental icing physics studies on electrically driven propellers in the Icing Research Tunnel (IRT). Some preliminary icing scaling evaluation tests were conducted on propellers for Advanced Air…13 pp
- A Preliminary Evaluation of Icing Scaling on AAM PropellersNASA Glenn Research Center recently developed a general-purpose propeller test stand for conducting fundamental icing physics studies on electrically driven propellers in the Icing Research Tunnel (IRT). Some preliminary icing scaling evaluation tests were conducted on propellers for Advanced Air…13 pp
- A Preliminary Evaluation of Supersonic Transport Category Vehicle Operations in the National Airspace SystemSeveral public sector businesses and government agencies, including the National Aeronautics and Space Administration are currently working on solving key technological barriers that must be overcome in order to realize the vision of low-boom supersonic flights conducted over land. However, once…13 pp20160005998
- A Preliminary Flight Investigation of Formation Flight for Drag Reduction on the C-17 AircraftMany theoretical and experimental studies have shown that aircraft flying in formation could experience significant reductions in fuel use compared to solo flight. To date, formation flight for aerodynamic benefit has not been thoroughly explored in flight for large transport-class vehicles. This…29 pp20120007201
- A Qualitative Piloted Evaluation of the Tupolev Tu-144 Supersonic TransportTwo U.S. research pilots evaluated the Tupolev Tu-144 supersonic transport aircraft on three dedicated flights: one subsonic and two supersonic profiles. The flight profiles and maneuvers were developed jointly by Tupolev and U.S. engineers. The vehicle was found to have unique operational and…47 pp20000025077
- A real time Pegasus propulsion system model for VSTOL piloted simulation evaluationA real time propulsion system modeling technique suitable for use in man-in-the-loop simulator studies was developd. This technique provides the system accuracy, stability, and transient response required for integrated aircraft and propulsion control system studies. A Pegasus-Harrier propulsion…18 pp19820005271
- A recontoured, upper surface designed to increase the maximum lift coefficient of a modified NACA 65 (0.82) (9.9) airfoil sectionA recontoured upper surface was designed to increase the maximum lift coefficient of a modified NACA 65 (0.82)(9.9) airfoil section which was tested at Mach numbers of 0.3 and 0.4 and Reynolds numbers of 2.3x10(6) and 4.3x10(6). The original 6-series section was tested for comparison with the…46 ppNASA-TM-85855
- A remote augmentor lift system with a turbine bypass engineTwo supersonic vertical takeoff or landing (VTOL) aircraft engine types, a conventional medium bypass ratio turbofan, and a turbine bypass turbojet were studied. The aircraft assumed was a clipped delta wing with canard configuration. A VTOL deck launched intercept, DLI, mission with Mach 1.6 dash…12 pp19830003817
- A review of NASA's propulsion programs for aviationA review of five NASA engine-oriented propulsion programs of major importance to civil aviation are presented and discussed. Included are programs directed at exploring propulsion system concepts for (1) energy conservation subsonic aircraft (improved current turbofans, advanced turbofans, and…22 pp19780008112
- A review of transport handling-qualities criteria in terms of preliminary XB-70 flight experienceFlight tests for preliminary evaluation of handling qualities of unaugmented XB-70 aircraft34 pp19680014432
- A revolutionary approach to composite construction and flight management systems for small, general aviation airplanesThe design studies for two composite general aviation airplanes are presented. The main consideration for both of the designs was to avoid the typical 'metal replacement' philosophy that has hindered the widespread use of composites in general aviation aircraft. The first design is for a low wing…12 pp19940021221
- A Roadmap for Aircraft Engine Life Extending ControlThe concept of Aircraft Engine Life Extending Control is introduced. A brief description of the tradeoffs between performance and engine life are first explained. The overall goal of the life extending controller is to reduce the engine operating cost by extending the on-wing engine life while…4 pp
- A Robust Uniform Control Approach for VTOL AircraftWe present a uniform control approach for transitioning vertical take-off and landing aircraft. The approach combines several well-understood linear techniques, including robust servomechanism linear quadratic regulation, control allocation, and gain scheduling, to provide a practical control…15 pp
- A rotor-mounted digital instrumentation system for helicopter blade flight research measurementsA rotor mounted flight instrumentation system developed for helicopter rotor blade research is described. The system utilizes high speed digital techniques to acquire research data from miniature pressure transducers on advanced rotor airfoils which are flight tested on an AH-1G helicopter. The…50 ppNASA-TP-1146
- A Sensitivity Study of Commercial Aircraft Engine Response for Emergency SituationsThis paper contains the details of a sensitivity study in which the variation in a commercial aircraft engine's outputs is observed for perturbations in its operating condition inputs or control parameters. This study seeks to determine the extent to which various controller limits can be modified…29 pp20110012021
- A Simple Analytical Fuselage-Induced Velocity Model for Comprehensive Rotor CodesA simple analytical model to account for fuselage-induced velocities at rotor blade elements and at rotor wake nodes is described. The method is applied to three different fuselage configurations. Results obtained with a comprehensive rotor code show the fuselage effect on rotor trim controls,…19 pp20190027229
- A Simple Method for High-Lift Propeller Conceptual DesignIn this paper, we present a simple method for designing propellers that are placed upstream of the leading edge of a wing in order to augment lift. Because the primary purpose of these "high-lift propellers" is to increase lift rather than produce thrust, these props are best viewed as a form of…41 pp20160007767
- A simulator and flight study of yaw coupling in turning maneuvers of large transport aircraftPiloted simulator study of yaw coupling in turning maneuvers of supersonic transport compared with flight test data on large variable stability jet transport39 pp19670014467
- A simulator study of a pictorial navigation display in instrument departures of the supersonic transportSimulator study of pictorial navigation display in instrument departure of supersonic transport23 ppNASA-TN-D-4029
- A simulator study of the supersonic transport in the air traffic control systemReal time environment and control simulation of supersonic transport in air traffic control system11 ppNASA-TM-X-51544
- A Status of NASA Rotorcraft ResearchIn 2006, NASA rotorcraft research was refocused to emphasize high-fidelity “first-principles” predictive tool development and validation. As part of this new emphasis, documenting the status of NASA rotorcraft research and defining the state-of-the-art in rotorcraft predictive capability were…418 pp20190002639
- A STUDY OF A PILOT'S ABILITY TO CONTROL DURING SIMULATED STABILITY AUGMENTATION SYSTEM FAILURESPilots ability to control during simulated stability augmenter failures40 ppNASA-TN-D-1552
- A study of ASRS reports involving general aviation and weather encountersConsideration is given to the nature and characteristics of problems involving dissemination of weather information, use of this information by pilots, its adequacy for the purpose intended, the ability of the air traffic control system to cope with weather related incidents, and the various…60 pp19810018525
- A study of NACA and NASA published information of pertinence in the design of light aircraft. Volume 2 - Aerodynamics and aerodynamic loadsCritical reviews of NACA and NASA report literature on aerodynamics and aerodynamic load calculations for light aircraft design708 pp19700012724
- A study of potential roles of supersonic transport crews and some implications for the flight deck. Volume I - Workload, crew roles, flight deck concepts, and conclusionsSupersonic transport crew roles, and workload implications on flight deck designNASA-CR-561
- A study of rotor broadband noise mechanisms and helicopter tail rotor noiseThe rotor broadband noise mechanisms considered are the following: (1) lift fluctuation due to turbulence ingestion; (2) boundary layer/trailing edge interaction; (3) tip vortex formation; and (4) turbulent vortex shedding from blunt trailing edge. Predictions show good agreement with available…192 ppNASA-CR-177565
- A study of the noise radiation from four helicopter rotor bladesAcoustic measurements were taken of a modern helicopter rotor with four blade tip shapes in the NASA Ames 40-by-80-Foot Wind Tunnel. The four tip shapes are: rectangular, swept, trapezoidal, and swept tapered in platform. Acoustic effects due to tip shape changes were studied based on the dBA…16 pp
- A summary of hingeless-rotor research at nasa- langleyFlight and wind tunnel tests of hingeless helicopter rotor30 ppNASA-TM-X-51513
- A summary of hingeless-rotor structural loads and dynamics researchResearch review on helicopter hingeless rotor structural loads and dynamics40 ppNASA-TM-X-56726
- A summary of recent large-scale research on high-lift devicesA brief summary of recent 40- by 80-foot wind-tunnel investigations of large-scale models equipped with various high-lift devices is presented. The basic high-lift concepts that were investigated were the externally blown flap, the augmentor wing, and the rotating-cylinder flap. The scope of this…17 pp19660015323
- A summary of results obtained during flight simulation of several aircraft prototypes with variable-stability airplanesDynamic lateral stability and handling data from flight simulation with F6F-3 and F-86A VARIABLE-STABILITY aircraft59 pp19660024791
- A summary of rotor-hub bending moments encountered by a high performance hingeless- rotor helicopter during nap-of-the-earth maneuversRotor-hub bending moment measurements on hingeless rotor helicopter during abrupt maneuvers near ground32 ppNASA-TN-D-4574
- A summary of rotorcraft handling qualities research at NASA Ames Research CenterThe objectives of the rotorcraft handling qualities research program at Ames Research Center are twofold: (1) to develop basic handling qualities design criteria to permit cost effective design decisions to be made for helicopters, and (2) to obtain basic handling qualities data for certification…18 pp19840012503
- A summary of the longitudinal and lateral stability and control characteristics obtained from rocket-model tests of a swept-wing fighter-type airplane at Mach numbers from 0.5 to 1.9Longitudinal and lateral stability and control characteristics of swept wing fighter aircraft79 ppNACA-RM-L56K19
- A summary of wind tunnel research on tilt rotors from hover to cruise flightAn experimental research program has been conducted on a series of tilt rotors designed for a range of blade twist in various wind tunnel facilities. The objective was to obtain precise results on the influence of blade twist and aeroelasticity on tilt rotor performance, from hover to high speed…18 pp19730010285
- A supersonic fan equipped variable cycle engine for a Mach 2.7 supersonic transportThe concept of a variable cycle turbofan engine with an axially supersonic fan stage as powerplant for a Mach 2.7 supersonic transport was evaluated. Quantitative cycle analysis was used to assess the effects of the fan inlet and blading efficiencies on engine performance. Thrust levels predicted…107 pp19860019474
- A survey of handling qualities criteria and their applications to high performance aircraftVarious handling qualities criteria and their application to high performance aircraft including state-of-the-art and highly augmented aircraft were surveyed. Neal-Smith, Bandwidth, Equivalent Systems, and Military Specification 8785 criteria are applied to flight test data from aircraft such as…68 pp19860021266
- A Synthesis of Hybrid RANS/LES CFD Results for F-16XL Aircraft AerodynamicsA synthesis is presented of recent numerical predictions for the F-16XL aircraft flow fields and aerodynamics. The computational results were all performed with hybrid RANS/LES formulations, with an emphasis on unsteady flows and subsequent aerodynamics, and results from five computational methods…29 pp20160006054
- A system for varying the stability and control of a deflected-jet fixed-wing vtol aircraftVariable control power and augmented stability for hovering VTOL aircraft30 ppNASA-TN-D-2700
- A Terminal Area Icing Remote Sensing SystemNASA and the National Center for Atmospheric Research (NCAR) have developed an icing remote sensing technology that has demonstrated skill at detecting and classifying icing hazards in a vertical column above an instrumented ground station. This technology is now being extended to provide…16 ppNASA/TM-2014-218417
- A theoretical analysis of airplane longitudinal stability and control as affected by wind shearThe longitudinal equations of motion with wind shear terms were used to analyze the stability and motions of a jet transport. A positive wind shear gives a decreasing head wind or changes a head wind into a tail wind. A negative wind shear gives a decreasing tail wind or changes a tail wind into a…55 ppNASA-TN-D-8496
- A Theoretical Investigation of the Drag of Generalized Aircraft Configurations in Supersonic FlowIt seems possible that, in supersonic flight, unconventional arrangements of wings and bodies may offer advantages in the form of drag reduction. It is the purpose of this report to consider the methods for determining the pressure drag for such unconventional configurations, and to consider a few…20040034216
- A theory of flight flutter testingFlight flutter testing is considered as a method for finding generalized aerodynamic forces. The coefficients determined from flight flutter tests are used in flutter calculations, using a simple expansion in frequency and Mach number. The errors in the procedure are discussed, and expressions for…4 pp19760003008
- A variable-gain output feedback control design methodologyA digital control system design technique is developed in which the control system gain matrix varies with the plant operating point parameters. The design technique is obtained by formulating the problem as an optimal stochastic output feedback control law with variable gains. This approach…91 ppNASA-CR-4226
- A wind tunnel flight correlation of Apollo 16 sonic boomA correlation of sonic boom pressure signatures recorded during reentry of the Apollo 16 command module with wind-tunnel signatures extrapolated to flight distances was made for Mach numbers of 1.83 and 9.71. The flight pressure signatures were recorded by microphones located onboard ships…22 ppNASA-TM-X-62073
- A wind tunnel investigation of panel response to boundary layer pressure fluctuations at Mach 1.4 and Mach 3.5Panel response to turbulent boundary layer pressure fluctuations in wind tunnel with supersonic flow84 pp19660017569
- A Wind-Tunnel Investigation of Tilt-Rotor Gust Alleviation SystemsThe alleviation of the effects of gusts on tilt rotor aircraft by means of active control systems was investigated. The gust generator, the derivation of the equations of motion of the rotor wing combination, the correlation of these equations with the results of wind tunnel model tests, the use of…140 pp19790017891
- A-10/TF34 Turbine Engine Monitoring System (TEMS)The hardware and software development of the A-10/TF34 turbine engine monitoring system (TEMS) is described. The operation and interfaces of the A-10/TF34 TEMS hardware are discussed with particular emphasis on function, capabilities, and limitations. The TEMS data types are defined and the various…14 pp
- AAS/GSFC 13th International Symposium on Space Flight DynamicsThis conference proceedings preprint includes papers and abstracts presented at the 13th International Symposium on Space Flight Dynamics, May 11-15, 1998. Co-sponsored by American Astronautical Society and the Guidance, Navigation and Control Center of the Goddard Space Flight Center, this…534 ppNASA/CP-1998-206858/VOL2
- AAS/GSFC 13th International Symposium on Space Flight DynamicsThis conference proceedings preprint includes papers and abstracts presented at the 13th International Symposium on Space Flight Dynamics. Cosponsored by American Astronautical Society and the Guidance, Navigation and Control Center of the Goddard Space Flight Center, this symposium featured…540 ppNASA/CP-1998-206858/Vol-1
- Abe Silverstein 10- by 10-Foot Supersonic Wind Tunnel Validated for Low-Speed (Subsonic) OperationThe NASA Glenn Research Center and Lockheed Martin Corporation tested an aircraft model in two wind tunnels to compare low-speed (subsonic) flow characteristics. Objectives of the test were to determine and document the similarities and uniqueness of the tunnels and to validate that Glenn's 10- by…2 pp
- Abort Flight Test Project OverviewA general overview of the Orion abort flight test is presented. The contents include: 1) Abort Flight Test Project Overview; 2) DFRC Exploration Mission Directorate; 3) Abort Flight Test; 4) Flight Test Configurations; 5) Flight Test Vehicle Engineering Office; 6) DFRC FTA Scope; 7) Flight Test…10 pp
- Accelerations in Landing with a Tricycle-Type Landing GearIn connection with the application of stable tricycle-type landing gears to transport airplanes, the question arises as to whether certain passengers may not experience relatively great accelerations in an emergency landing. Since the main landing wheels are behind the center of gravity in this…18 ppNACA-SR-61
- Acoustic Improvements to the 9- by 15-Foot Low Speed Wind TunnelA major refurbishment of the 9- by 15-Foot Low Speed Wind Tunnel at NASA Glenn Research Center was undertaken between 2016 and 2019 to improve the acoustic measurement capability of the facility. The principal objective was to lower the background noise in the test section so quiet aircraft…14 pp
- Acoustic Measurements from Wind Tunnel Test of AMELIA - Advanced Model for Extreme Lift and Improved AeroacousticsA wind tunnel test has been conducted to measure the aerodynamic and acoustic performance of an active circulation-control aircraft with leading- and trailing- edge slot blowing. The 11 Advanced Model for Extreme Lift and Improved Aeroacoustics (AMELIA) model was tested in the Arnold Engineering…91 ppNASA/TM-2014-218862
- Acoustic Measurements of a Large Civil Transport Main Landing Gear ModelMicrophone phased array acoustic measurements of a 26 percent-scale, Boeing 777-200 main landing gear model with and without noise reduction fairings installed were obtained in the anechoic configuration of the Virginia Tech Stability Tunnel. Data were acquired at Mach numbers of 0.12, 0.15, and…26 ppNF1676L-23033
- Acoustic Methods Used in the NASA Glenn 9- by 15- Foot Low-Speed Wind TunnelThe 9- by 15-Foot Low Speed Wind Tunnel has been used for acoustic testing for more than 40 years. The facility is principally used for testing aircraft engine propulsion components, for both aerodynamic performance and acoustics. The present report discusses the instrumentation and procedures…50 pp20180004163
- Acoustic Performance of Drive Rig Mufflers for Model Scale Engine TestingAircraft engine component testing at the NASA Glenn Research Center (GRC) includes acoustic testing of scale model fans and propellers in the 9- by15-Foot Low Speed Wind Tunnel (LSWT). This testing utilizes air driven turbines to deliver power to the article being studied. These air turbines…20 pp20140000338
- Acoustic Testing of the Tiltrotor Test Rig in the National Full-Scale Aerodynamics Complex 40- by 80-Foot Wind TunnelThe Tiltrotor Test Rig (TTR) was tested in the National Full-Scale Aerodynamics Complex (NFAC) 40- by 80-Foot Wind Tunnel from 2017 to 2018. The rotor system can be configured in airplane mode, with the rotor plane perpendicular to the wind flow, and in helicopter mode, with the rotor plane…5 ppARC-E-DAA-TN62155
- Acoustical characteristics of the NASA Langley full scale wind tunnel test sectionThe full-scale wind tunnel at NASA-Langley Research Center was designed for low-speed aerodynamic testing of aircraft. Sound absorbing treatment has been added to the ceiling and walls of the tunnel test section to create a more anechoic condition for taking acoustical measurements during…44 ppNASA-CR-132604
- Active Aircraft Pylon Noise Control SystemAn active pylon noise control system for an aircraft includes a pylon structure connecting an engine system with an airframe surface of the aircraft and having at least one aperture to supply a gas or fluid therethrough, an intake portion attached to the pylon structure to intake a gas or fluid, a…11 pp20150009341
- Active Aircraft Pylon Noise Control SystemAn active pylon noise control system for an aircraft includes a pylon structure connecting an engine system with an airframe surface of the aircraft and having at least one aperture to supply a gas or fluid therethrough, an intake portion attached to the pylon structure to intake a gas or fluid, a…11 pp20170006146
- Active Control of Wind-Tunnel Model Aeroelastic Response Using Neural NetworksNASA Langley Research Center, Hampton, VA 23681 Under a joint research and development effort conducted by the National Aeronautics and Space Administration and The Boeing Company (formerly McDonnell Douglas) three neural-network based control systems were developed and tested. The control systems…10 pp20040086574
- Active Flutter Suppression Controllers Derived from Linear and Nonlinear Aerodynamics: Application to a Transport Aircraft ModelActive flutter suppression has been demonstrated in simulation by many researchers, generally using methods based on linear aerodynamics and often with simplistic geometries. In this paper, active flutter suppression is demonstrated in a simulation using a Navier-Stokes aerodynamics code, FUN3D…12 pp20190000880
- Active Structural Control for Aircraft Efficiency with the X-56A AircraftThe X-56A Multi-Utility Technology Testbed is an experimental aircraft designed to study active control of flexible structures. The vehicle is easily reconfigured to allow for testing of different configurations. The vehicle is being used to study new sensor, actuator, modeling and controls…15 ppAFRC-E-DAA-TN27228
- Active Turbine Tip Clearance Control Trade Space Analysis of an Advanced Geared Turbofan EngineTip clearance within the high pressure turbine of a gas turbine engine is a significant factor in engine performance and efficiency. In the pursuit of higher efficiency, aero-engine designs are migrating toward compact gas turbine (CGT) technology that seeks to increase the bypass ratio of the gas…23 pp20180006648
- Active Vertical Tail Buffeting Alleviation on an F/A-18 Model in a Wind TunnelA 1/6-scale F-18 wind-tunnel model was tested in the Transonic Dynamics Tunnel at the NASA Langley Research Center as part of the Actively Controlled Response Of Buffet-Affected Tails (ACROBAT) program to assess the use of active controls in reducing vertical tail buffeting. The starboard vertical…10 pp19990028762
- Adaptive Control and Scaling Approach for the Emulation of Dynamic Sub-scale Torque LoadsPrevious research by the authors proposed a control and scaling approach for emulating dynamic sub-scale torque loads. This approach produced an emulation controller that successfully regulated the dynamic behavior of a sub-scale electro-mechanical system intended to be a dynamical representation…12 pp
- Adaptive Control and Scaling Approach for the Emulation of Dynamic Subscale Torque LoadsPrevious research by the authors proposed a control and scaling approach for emulating dynamic sub-scale torque loads. This approach produced an emulation controller that successfully regulated the dynamic behavior of a sub-scale electro-mechanical system intended to be a dynamical representation…15 pp
- Adaptive Control of a Transport Aircraft Using Differential ThrustThe paper presents an adaptive control technique for a damaged large transport aircraft subject to unknown atmospheric disturbances such as wind gust or turbulence. It is assumed that the damage results in vertical tail loss with no rudder authority, which is replaced with a differential thrust…15 ppARC-E-DAA-TN806
- Adaptive Control Using Neural Network Augmentation for a Modified F-15 AircraftDescription of the performance of a simplified dynamic inversion controller with neural network augmentation follows. Simulation studies focus on the results with and without neural network adaptation through the use of an F-15 aircraft simulator that has been modified to include canards. Simulated…6 pp
- Adaptive Data-based Predictive Control for Short Take-off and Landing (STOL) AircraftData-based Predictive Control is an emerging control method that stems from Model Predictive Control (MPC). MPC computes current control action based on a prediction of the system output a number of time steps into the future and is generally derived from a known model of the system. Data-based…13 ppARC-E-DAA-TN522
- Adaptive Failure Compensation for Aircraft Flight Control Using Engine Differentials: RegulationThe problem of using engine thrust differentials to compensate for rudder and aileron failures in aircraft flight control is addressed in this paper in a new framework. A nonlinear aircraft model that incorporates engine di erentials in the dynamic equations is employed and linearized to describe…25 ppAIAA Paper 2005-6996
- Adaptive Failure Compensation for Aircraft Tracking Control Using Engine Differential Based ModelAn aircraft model that incorporates independently adjustable engine throttles and ailerons is employed to develop an adaptive control scheme in the presence of actuator failures. This model captures the key features of aircraft flight dynamics when in the engine differential mode. Based on this…6 pp
- Adaptive Flight Control for Aircraft Safety EnhancementsThis poster presents the current adaptive control research being conducted at NASA ARC and LaRC in support of the Integrated Resilient Aircraft Control (IRAC) project. The technique "Approximate Stability Margin Analysis of Hybrid Direct-Indirect Adaptive Control" has been developed at NASA ARC to…1 ppARC-E-DAA-TN-219
- Adaptive Modal Identification for Flutter Suppression ControlIn this paper, we will develop an adaptive modal identification method for identifying the frequencies and damping of a flutter mode based on model-reference adaptive control (MRAC) and least-squares methods. The least-squares parameter estimation will achieve parameter convergence in the presence…14 pp20160008950
- Additional On-Surface and Off-Surface Aerodynamic Data for Partially-Dressed Cavity-Closed Nose Landing Gear Benchmark (PDCC-NLG)Additional aerodynamic data for the benchmark configuration of partially-dressed cavity-closed nose landing gear (PDCC-NLG), obtained at a flow Mach number of 0.166, are provided in this presentation. A detailed account of the unsteady surface pressure fluctuations acquired with a Kulite transducer…14 pp20200004593
- Adjustment of Adaptive Gain with Bounded Linear Stability Analysis to Improve Time-Delay Margin for Metrics-Driven Adaptive ControlThis paper presents the application of Bounded Linear Stability Analysis (BLSA) method for metrics driven adaptive control. The bounded linear stability analysis method is used for analyzing stability of adaptive control models, without linearizing the adaptive laws. Metrics-driven adaptive control…13 ppARC-E-DAA-TN528
- Advanced Approaches to Fatigue EvaluationConference on fatigue test evaluation for aircraft structures676 ppNASA-SP-309
- Advanced composite vertical stabilizer for DC-10 transport aircraftStructural design, tooling, fabrication, and test activities are reported for a program to develop an advanced composite vertical stabilizer (CVS) for the DC 10 Commercial Transport Aircraft. Structural design details are described and the status of structural and weight analyses are reported. A…216 pp19830023324
- Advanced control technology and its potential for future transport aircraftThis document is a compilation of papers presented at a symposium on advanced control technology held in Los Angeles, Calif. , July 9 to 11. 1974. Papers were presented by representatives of industry, the Air Force, and various NASA Centers. The topics covered included fly by wire, digital control,…1,051 ppNASA-TM-X-3409
- Advanced general aviation comparative engine/airframe integration studyThe NASA Advanced Aviation Comparative Engine/Airframe Integration Study was initiated to help determine which of four promising concepts for new general aviation engines for the 1990's should be considered for further research funding. The engine concepts included rotary, diesel, spark ignition,…135 pp19820014389
- Advanced general aviation engine/airframe integration studyA comparison of the in-airframe performance and efficiency of the advanced engine concepts is presented. The results indicate that the proposed advanced engines can significantly improve the performance and economy of general aviation airplanes. The engine found to be most promising is the highly…134 pp19820014394
- Advanced general aviation propeller studyMethods for predicting the performance, noise, weight, and cost of propellers for advanced general aviation aircraft of the 1980 time period were developed and computerized. This basic program was refined to incorporate a method of including the blade shape parameter, integrated design lift…49 pp19720010354
- Advanced general aviation propeller studySensitivity analysis of advance propeller configurations designed for general aviation aircraft of 1980 time period204 pp19710025730
- Advanced General Aviation Turbine Engine (GATE) conceptsConcepts are discussed that project turbine engine cost savings through use of geometrically constrained components designed for low rotational speeds and low stress to permit manufacturing economies. Aerodynamic development of geometrically constrained components is recommended to maximize…189 pp19790016846
- Advanced General Aviation Turbine Engine (GATE) studyThe small engine technology requirements suitable for general aviation service in the 1987 to 1988 time frame were defined. The market analysis showed potential United States engines sales of 31,500 per year providing that the turbine engine sales price approaches current reciprocating engine…149 pp19790021018
- Advanced hypersonic aircraft designThe objective of this design project is to develop the hypersonic reconnaissance aircraft to replace the SR-71 and to complement existing intelligence gathering devices. The initial design considerations were to create a manned vehicle which could complete its mission with at least two airborne…87 pp19930008848
- Advanced instrumentation for aircraft icing researchA compact and rugged probe based on the phase Doppler method was evaluated as a means for characterizing icing clouds using airborne platforms and for advancing aircraft icing research in large scale wind tunnels. The Phase Doppler Particle Analyzer (PDPA) upon which the new probe was based is now…106 ppNASA-CR-185225
- Advanced Propulsion System Studies for General Aviation AircraftIn this study, new technology engines were defined in two power classes: a 200 hp class, for a light, 4-place personal aircraft, and a 1500 pound thrust class for a twin-engined, 6 place business jet type aircraft. The engines were evaluated for retrofitting suitable current production aircraft for…123 pp20030068170
- Advanced Propulsion System Studies for General Aviation AircraftThis final report addresses the following topics: Market Impact Analysis (1) assessment of general aviation, including commuter/regional, aircraft market impact due to incorporation of advanced technology propulsion system on acquisition and operating costs, job creation and/or manpower demand, and…129 pp20030068101
- Advanced Propulsion Systems Study for General Aviation AircraftThis study defines a family of advanced technology Stratified Charge Rotary Engines (SCRE) appropriate for the enablement of the development of a new generation of general aviation aircraft. High commonality, affordability, and environmental compatibility are considerations influencing the family…176 pp20030062917
- Advanced Short Takeoff and Vertical Landing (ASTOVL) Concepts TestedIn this cooperative program between NASA, Lockheed Corporation, and the Advanced Research and Projects Agency (ARPA), an advanced short takeoff and vertical landing (ASTOVL) model was tested in the 9- by 15-Foot Low-Speed Wind Tunnel at the NASA Lewis Research Center. The 10-percent scaled model…1 pp20050169204
- Advanced symbology for general aviation approach to landing displaysA set of flight tests designed to evaluate the relative utility of candidate displays with advanced symbology for general aviation terminal area instrument flight rules operations are discussed. The symbology was previously evaluated as part of the NASA Langley Research Center's Terminal Configured…13 pp19840003971
- Advanced technology composite aircraft structuresWork performed during the 25th month on NAS1-18889, Advanced Technology Composite Aircraft Structures, is summarized. The main objective of this program is to develop an integrated technology and demonstrate a confidence level that permits the cost- and weight-effective use of advanced composite…126 pp19930020309
- Advanced turboprop testbed systems study. Volume 1: Testbed program objectives and priorities, drive system and aircraft design studies, evaluation and recommendations and wind tunnel test plansThe establishment of propfan technology readiness was determined and candidate drive systems for propfan application were identified. Candidate testbed aircraft were investigated for testbed aircraft suitability and four aircraft selected as possible propfan testbed vehicles. An evaluation of the…373 ppNASA-CR-167928-VOL-1
- Advanced wing design survivability testing and resultsComposite wings on current operational aircraft are conservatively designed to account for stress/strain concentrations, and to assure specified damage tolerance. The technology that can lead to improved composite wing structures and associated structural efficiency is to increase design ultimate…15 pp
- Advancement of proprotor technology. Task 2: Wind-tunnel test resultsAn advanced-design 25-foot-diameter flightworthy proprotor was tested in the NASA-Ames Large-Scale Wind Tunnel. These tests, have verified and confirmed the theory and design solutions developed as part of the Army Composite Aircraft Program. This report presents the test results and compares them…233 ppNASA-CR-114363
- Advances in Aero-Propulsive Modeling for Fixed-Wing and eVTOL Aircraft Using Experimental DataSmall unmanned aircraft and electric vertical takeoff and landing (eVTOL) aircraft have recently emerged as vehicles able to perform new missions and stimulate future air transportation methods. This dissertation presents several system identification research advancements for these modern aircraft…262 pp
- Advances in Aircraft System Identification at NASA Langley Research CenterAircraft system identification involves the determination of dynamic models from measured flight data. Recently, the Journal of Aircraft published a special issue in which authors summarized advances in aircraft system identification made at their institutions over the last 20 years. This talk…33 pp
- Advances in Experiment Design for High Performance AircraftA general overview and summary of recent advances in experiment design for high performance aircraft is presented, along with results from flight tests. General theoretical background is included, with some discussion of various approaches to maneuver design. Flight test examples from the F-18 High…20 pp19980201124
- Advances in Fatigue and Fracture Mechanics Analyses for Aircraft StructuresThis paper reviews some of the advances that have been made in stress analyses of cracked aircraft components, in the understanding of the fatigue and fatigue-crack growth process, and in the prediction of residual strength of complex aircraft structures with widespread fatigue damage.…40 pp
- Advances in Fatigue and Fracture Mechanics Analyses for Metallic Aircraft StructuresThis paper reviews some of the advances that have been made in stress analyses of cracked aircraft components, in the understanding of the fatigue and fatigue-crack growth process, and in the prediction of residual strength of complex aircraft structures with widespread fatigue damage.…45 ppNASA/TM-2000-210084
- Aero-Propulsive Damping Characterization for eVTOL Aircraft Using Free Motion Wind-Tunnel TestingThis paper describes an electric vertical takeoff and landing (eVTOL) aircraft system identification method applied using three degree-of-freedom (3DOF) free motion wind-tunnel testing. The approach, similar to flight-test system identification, allows for efficient mathematical model development…23 pp
- Aero-Propulsive Modeling for eVTOL Aircraft Using Wind Tunnel Testing with Multisine InputsA novel approach for modeling the aero-propulsive characteristics of an electric vertical takeoff and landing (eVTOL) aircraft was developed and demonstrated in wind tunnel testing. The approach was applied to the NASA LA-8 tandem tilt-wing eVTOL aircraft, using an efficient, hybrid experiment…28 pp
- Aeroacoustic Analysis of a Simplified Landing GearA hybrid approach is used to investigate the noise generated by a simplified landing gear without small scale parts such as hydraulic lines and fasteners. The Ffowcs Williams and Hawkings equation is used to predict the noise at far-field observer locations from flow data provided by an unsteady…12 ppAIAA Paper 2004-2887
- Aeroacoustic Evaluation of Flap and Landing Gear Noise Reduction ConceptsAeroacoustic measurements for a semi-span, 18% scale, high-fidelity Gulfstream aircraft model are presented. The model was used as a test bed to conduct detailed studies of flap and main landing gear noise sources and to determine the effectiveness of numerous noise mitigation concepts. Using a…28 ppNF1676L-17628
- Aerodynamic Characteristics at High and Low Subsonic Mach Numbers of the NACA 0012, 64(sub 2)-015, and 64(sub 3)-018 Airfoil Sections at Angles of Attack from -2 Degrees to 30 DegreesAn investigation has been made in the Langley low-turbulence pressure tunnel of the aerodynamic characteristics of the NACA 0012, 64(sub 2)-015, and 64(sub 3)-018 airfoil sections. Data were obtained at Mach numbers from 0.3 to that for tunnel choke, at angles of attack from -2deg to 30deg, and…16 ppNACA-RM-L54H06a
- Aerodynamic Characteristics of a Number of Modified NACA Four-Digit-Series Airfoil SectionsTheoretical pressure distributions and measured lift, drag, and pitching moment characteristics at three values of Reynolds number are presented for a group of NACA four-digit-series airfoil sections modified for high-speed applications. The effectiveness of flaps applied to these airfoils and the…40 ppNACA-RM-L7I22
- Aerodynamic characteristics of a powered tilt-proprotor wind tunnel modelAn investigation was conducted in the Langley V/STOL tunnel to determine the performance, stability and control, and rotor-wake interaction effects of a powered tilt-proprotor aircraft model with gimbal-hub rotors. Tests were conducted at representative flight conditions for hover, helicopter,…274 pp19760020125
- Aerodynamic characteristics of forebody and nose strakes based on F-16 wind tunnel test experience. Volume 1: Summary and analysisThe YF-16 and F-16 developmental wind tunnel test program was reviewed. Geometrical descriptions, general comments, representative data, and the initial efforts toward the development of design guides for the application of strakes to future aircraft are presented.144 ppNASA-CR-3053
- Aerodynamic characteristics of forebody and nose strakes based on F-16 wind tunnel test experience. Volume 2: Data baseThe YF-16 and F-16 developmental wind tunnel test program was reviewed and all force data pertinent to the design of forebody and nose strakes extracted. A complete set of these data is presented without analysis.755 ppNASA-CR-158922
- Aerodynamic Characteristics of Four NACA Airfoil Sections Designed for Helicopter Rotor Blades24 ppNACA-WR-L-29
- Aerodynamic Characteristics of Four Republic Airfoil Sections from Tests in Langley Two-Dimensional Low-Turbulence TunnelsFour airfoils sections, designed by the Republic Aviation Corporation for the root and tip sections of the XF-12 airplane, were tested in the Langley two-dimensional low-turbulence tunnels to obtain their aerodynamic characteristics. Lift characteristics were obtained at Reynolds numbers of…19 ppNACA-MR-L5I19
- Aerodynamic Characteristics of NACA 23012 and 23021 Airfoils with 20-Percent-chord External-Airfoil Flaps of NACA 23012 SectionReport presents the results of an investigation of the general aerodynamic characteristics of the NACA 23012 and 23021 airfoils, each equipped with a 0.20c external flap of NACA 23012 section. The tests were made in the NACA 7 by 10-foot and variable-density wind tunnels and covered a range of…25 ppNACA-TR-573
- Aerodynamic characteristics of the 40- by 80/80- by 120-foot wind tunnel at NASA Ames Research CenterThe design and testing of vane sets and air-exchange inlet for the 40 x 80/80 x 120-ft wind tunnel at NASA Ames are reported. Boundary-layer analysis and 2D and 3D inviscid panel codes are employed in computer models of the system, and a 1/10-scale 2D facility and a 1/50-scale 3D model of the…26 pp19840015554
- Aerodynamic data banks for Clark-Y, NACA 4-digit and NACA 16-series airfoil familiesWith the renewed interest in propellers as means of obtaining thrust and fuel efficiency in addition to the increased utilization of the computer, a significant amount of progress was made in the development of theoretical models to predict the performance of propeller systems. Inherent in the…174 ppNASA-CR-176883
- Aerodynamic Design and Estimated Performance of a Two-stage Curtis Turbine for the Liquid Oxygen Turbopump of the M-1 EngineTwo-stage turbine for liquid oxygen turbopump of M-1 rocket engine75 ppNASA-CR-54764
- Aerodynamic Design of Integrated Propulsion-Airframe Configuration of the Hybrid Wing-Body AircraftHybrid Wing Body (HWB) aircraft is characterized by a flattened and airfoil-shaped body, which produces a substantial portion of the total lift. The body form is composed of distinct and separate wing structures, though the wings are smoothly blended into the body. This concept has been studied…27 ppGRC-E-DAA-TN43199
- Aerodynamic Effects Caused by Icing of an Unswept NACA 65A004 AirfoilThe effects of ice formations on the section lift, drag, and pitching-moment coefficients of an unswept NACA 65A004 airfoil section of 6-foot chord were studied.. The magnitude of the aerodynamic penalties was primarily a function of the shape and size of the ice formation near the leading edge of…48 ppNACA-TN-4155
- Aerodynamic Flight-Test Results for the Adaptive Compliant Trailing EdgeThe aerodynamic effects of compliant flaps installed onto a modified Gulfstream III airplane were investigated. Analyses were performed prior to flight to predict the aerodynamic effects of the flap installation. Flight tests were conducted to gather both structural and aerodynamic data. The…21 ppDFRC-E-DAA-TN31619
- Aerodynamic Interaction Effects of a Helicopter Rotor and FuselageA three year Cooperative Research Agreements made in each of the three years between the Subsonic Aerodynamics Branch of the NASA Langley Research Center and the Virginia Polytechnic Institute and State University (Va. Tech) has been completed. This document presents results from this three year…216 pp
- Aerodynamic Parameters of High Performance Aircraft Estimated from Wind Tunnel and Flight Test DataA concept of system identification applied to high performance aircraft is introduced followed by a discussion on the identification methodology. Special emphasis is given to model postulation using time invariant and time dependent aerodynamic parameters, model structure determination and…20 ppNASA/TM-1997-207993
- Aerodynamic stability and control of ducted- propeller aircraftTest results from studies of small and large powered models of a dual, tandem, ducted-propeller VTOL design are reviewed, with emphasis on stability and control characteristics through the transition speed range. The characteristics are generally satisfactory. Stability augmentation may be…
- Aerodynamics model for a generic ASTOVL lift-fan aircraftThis report describes the aerodynamics model used in a simulation model of an advanced short takeoff and vertical landing (ASTOVL) lift-fan fighter aircraft. The simulation model was developed for use in piloted evaluations of transition and hover flight regimes, so that only low speed (M…64 pp19950019882
- Aerodynamics of a Gulfstream G550 Nose Landing Gear ModelIn this paper we discuss detailed steady and unsteady aerodynamic measurements of a Gulfstream G550 nose landing gear model. The quarter-scale, high-fidelity model includes part of the lower fuselage and the gear cavity. The full model configuration allowed for removal of various gear components…24 ppLF99-8007
- Aerodynamics of airframe-engine integration of supersonic aircraftAerodynamics of airframe-engine integration of supersonic aircraft42 pp19660023256
- Aerodynamics of the Viggen 37 aircraft. Part 1: General characteristics at low speedA description of the aerodynamics of the Viggen 37 and its performances, especially at low speeds is presented. The aerodynamic requirements for the design of the Viggen 37 aircraft are given, including the basic design, performance requirement, and aerodynamic characteristics, static and dynamic…142 pp19860019453
- Aerodynamics/ACEE: Aircraft energy efficiencyAn overview is presented of a 10 year program managed by NASA which seeks to make possible the most efficient use of energy for aircraft propulsion and lift as well as provide a technology that can be used by U.S. manufacturers of air transports and engines. Supercritical wings, winglets, vortex…9 pp19820017365
- Aeroelastic control of oblique-wing aircraftThe U.S. Navy and NASA are currently involved in the design and development of an unsymmetric-skew-wing aircraft capable of 65 deg wing sweep and flight at Mach 1.6. A generic skew-wing aircraft model was developed for 45 deg wing skew at a flight condition of Mach 0.70 and 3048 m altitude. At this…14 ppNASA-TM-86808
- Aeroelastic Deformation: Adaptation of Wind Tunnel Measurement Concepts to Full-Scale Vehicle Flight TestingThe adaptation of a proven wind tunnel test technique, known as Videogrammetry, to flight testing of full-scale vehicles is presented. A description is presented of the technique used at NASA's Dryden Flight Research Center for the measurement of the change in wing twist and deflection of an F/A-18…17 ppRTO-MP-AVT-124
- Aeroelastic Deformation: Adaptation of Wind Tunnel Measurement Concepts to Full-Scale Vehicle Flight TestingThe adaptation of a proven wind tunnel test technique, known as Videogrammetry, to flight testing of full-scale vehicles is presented. A description is presented of the technique used at NASA's Dryden Flight Research Center for the measurement of the change in wing twist and deflection of an F/A-18…24 ppNASA/TM-2005-213790
- Aeroelastic model helicopter rotor testing in the Langley TDTWind-tunnel testing of a properly scaled aeroelastic model helicopter rotor is considered a necessary phase in the design development of new or existing rotor systems. For this reason, extensive testing of aeroelastically scaled model rotors is done in the Transonic Dynamics Tunnel (TDT) located at…19 ppNASA-TM-86440
- Aeroelastic Modeling of Elastically Shaped Aircraft Concept via Wing Shaping Control for Drag ReductionLightweight aircraft design has received a considerable attention in recent years as a means for improving cruise efficiency. Reducing aircraft weight results in lower lift requirements which directly translate into lower drag, hence reduced engine thrust requirements during cruise. The use of…29 ppARC-E-DAA-TN5691
- Aeroelastic modeling of the active flexible wing wind-tunnel modelThe primary issues involved in the generation of linear, state-space equations of motion of a flexible wind tunnel model, the Active Flexible Wing (AFW), are discussed. The codes that were used and their inherent assumptions and limitations are also briefly discussed. The application of the CAP-TSD…38 pp19910013020
- Aeroelastic Tailoring Study of N+2 Low Boom Supersonic Commerical Transport AircraftThe Lockheed Martin N+2 Low - boom Supersonic Commercial Transport (LSCT) aircraft was optimized in this study through the use of a multidisciplinary design optimization tool developed at the National Aeronautics and S pace Administration Armstrong Flight Research Center. A total of 111 design…29 ppDFRC-E-DAA-TN22615
- Aeroelastic Tailoring Study of N+2 Low-Boom Supersonic Commercial Transport AircraftThe Lockheed Martins N+2 Low-boom Supersonic Commercial Transport (LSCT) aircraft is optimized in this study through the use of a multidisciplinary design optimization tool developed at the NASA Armstrong Flight Research Center. A total of 111 design variables are used in the first optimization…34 ppDFRC-E-DAA-TN22756
- Aeroelasticity matters: Some reflections on two decades of testing in the NASA Langley transonic dynamics tunnelTesting of wind-tunnel aeroelastic models is a well established, widely used means of studying flutter trends, validating theory and investigating flutter margins of safety of new vehicle designs. The Langley Transonic Dynamics Tunnel was designed specifically for work on dynamics and aeroelastic…24 pp19820004168
- Aeroelasticity of Axially Loaded Aerodynamic Structures for Truss-Braced Wing AircraftThis paper presents an aeroelastic finite-element formulation for axially loaded aerodynamic structures. The presence of axial loading causes the bending and torsional sitffnesses to change. For aircraft with axially loaded structures such as the truss-braced wing aircraft, the aeroelastic…26 pp20160000197
- AERONAUTICAL LAB. EXAMINATION OF RECENT LATERAL-STABILITY-DERIVATIVE DATAStability derivatives affecting lateral behavior of aircraft and missiles28 pp19630010648
- Aeroservoelastic Control Law Development for the Integrated Adaptive Wing Technology Maturation Wind-Tunnel TestThe NASA Advanced Air Transport Technology (AATT) Project seeks to “explore and develop technologies and concepts for improved energy efficiency and environmental compatibility for fixed wing subsonic transports” [1]. The IAWTM project is a subproject within AATT and is a joint Boeing/NASA effort…9 pp
- Aeroservoelastic Modeling of Body Freedom Flutter for Control System DesignOne of the most severe forms of coupling between aeroelasticity and flight dynamics is an instability called freedom flutter. The existing tools often assume relatively weak coupling, and are therefore unable to accurately model body freedom flutter. Because the existing tools were developed from…19 pp20170000455
- Aeroservoelastic wind-tunnel investigations using the Active Flexible Wing Model: Status and recent accomplishmentsThe status of the joint NASA/Rockwell Active Flexible Wing Wind-Tunnel Test Program is described. The objectives are to develop and validate the analysis, design, and test methodologies required to apply multifunction active control technology for improving aircraft performance and stability. Major…14 ppNASA-TM-101570
- Aeroservoelastic Wind-Tunnel Test of the SUGAR Truss Braced Wing Wind-Tunnel ModelThe Subsonic Ultra Green Aircraft Research (SUGAR) Truss-Braced Wing (TBW) aeroservoelastic (ASE) wind-tunnel test was conducted in the NASA Langley Transonic Dynamics Tunnel (TDT) and was completed in April, 2014. The primary goals of the test were to identify the open-loop flutter boundary and…28 ppNF1676L-18944
- Aeroservoelastic Wind-Tunnel Tests of a Free-Flying, Joined-Wing SensorCraft Model for Gust Load AlleviationA team comprised of the Air Force Research Laboratory (AFRL), Boeing, and the NASA Langley Research Center conducted three aeroservoelastic wind-tunnel tests in the Transonic Dynamics Tunnel to demonstrate active control technologies relevant to large, exible vehicles. In the first of these three…36 pp20110009997
- AFC-Enabled Simplified High-Lift System Integration StudyThe primary objective of this trade study report is to explore the potential of using Active Flow Control (AFC) for achieving lighter and mechanically simpler high-lift systems for transonic commercial transport aircraft. This assessment was conducted in four steps. First, based on the Common…39 pp20140012783
- AIFTDS stand-alone RMDU flight test reportThe remote multiplexer/digitizer unit for the airborne integrated flight test data system was subjected to a flight test environment in order to study its dynamic response and that of its associated instrumentation circuitry during an actual flight test. The shielding schemes and instrumentation…65 pp19790019996
- Air cushion landing gear applications studyA series of air cushion landing gear (ACLG) applications was studied and potential benefits analyzed in order to identify the most attractive of these. The selected applications are new integrated designs (not retrofits) and employ a modified design approach with improved characteristics and…84 ppNASA-CR-159002
- Aircraft control systemA solar rechargeable, long-duration, span-loaded flying wing, having no fuselage or rudder. Having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing's top surface, the aircraft uses only differential thrust of its eight propellers to turn, pitch and yaw. The wing is…43 ppPatent Application Number: US-Patent-Appl-SN-10/310,415
- Aircraft control systemAn aircraft control system is described which is particularly suited to rotary wing aircraft. Longitudinal acceleration and course rate commands are derived from a manual control stick to control translational velocity of the aircraft along a flight path. In the collective channel the manual…9 pp19730010277
- Aircraft control systemA span-loaded, highly flexible flying wing, having horizontal control surfaces mounted aft of the wing on extended beams to form local pitch-control devices. Each of five spanwise wing segments of the wing has one or more motors and photovoltaic arrays, and produces its own lift independent of the…13 ppPatent Application Number: US-Patent-Appl-SN-11/732,109
- Aircraft Control Using Engine Thrust: A History of Learning TOC Real-TimeA history of learning the operation of Throttles Only Control (TOC) to control an aircraft in real time using engine thrust is shown. The topics include: 1) Past TOC Accidents/Incidents; 2) 1972: DC-10 American Airlines; 3) May 1974: USAF B-52H; 4) April 1975: USAF C-5A; 5) April 1975: USAF C-5A;…38 pp
- Aircraft DesignThe present invention is an aircraft wing design that creates a bell shaped span load, which results in a negative induced drag (induced thrust) on the outer portion of the wing; such a design obviates the need for rudder control of an aircraft.11 ppPatent Application Number: US-Patent-Appl-SN-14/297,186
- Aircraft Design Considerations to Meet One Engine Inoperative (OEI) Safety RequirementsCommercial airlines are obligated to operate such that an aircraft can suffer an engine failure at any point in its mission and terminate the flight without an accident. Only minimal aircraft damage is allowable, such as brake replacement due to very heavy application, or an engine inspection…13 pp20120016833
- Aircraft Design SoftwareSuccessful commercialization of the AirCraft SYNThesis (ACSYNT) tool has resulted in the creation of Phoenix Integration, Inc. ACSYNT has been exclusively licensed to the company, an outcome of a seven year, $3 million effort to provide unique software technology to a focused design engineering…1 pp20020076250
- Aircraft digital control design methodsVariations in design methods for aircraft digital flight control are evaluated and compared. The methods fall into two categories; those where the design is done in the continuous domain (or s plane) and those where the design is done in the discrete domain (or z plane). Design method fidelity is…79 ppNASA-CR-148604
- Aircraft digital flight control technical reviewThe Aircraft Digital Flight Control Technical Review was initiated by two pilot induced oscillation (PIO) incidents in the spring and summer of 1992. Maj. Gen. Franklin (PEO) wondered why the Air Force development process for digital flight control systems was not preventing PIO problems.…50 pp
- Aircraft Electric Propulsion Systems Applied Research at NASAResearchers at NASA are investigating the potential for electric propulsion systems to revolutionize the design of aircraft from the small-scale general aviation sector to commuter and transport-class vehicles. Electric propulsion provides new degrees of design freedom that may enable opportunities…37 pp20160005232
- Aircraft Electric/Hybrid-Electric Power and Propulsion Workshop Perspective of the V/STOL Aircraft Systems Tech CommitteeThis presentation will be given at the AIAA Electric Hybrid-Electric Power Propulsion Workshop on July 29, 2016. The workshop is being held so the AIAA can determine how it can support the introduction of electric aircraft into the aerospace industry. This presentation will address the needs of the…12 pp20160010060
- Aircraft energy efficiency laminar flow control wing design studyAn engineering design study was performed in which laminar flow control (LFC) was integrated into the wing of a commercial passenger transport aircraft. A baseline aircraft configuration was selected and the wing geometry was defined. The LFC system, with suction slots, ducting, and suction pumps…37 pp19780005099
- Aircraft Engine DiagnosticsEngine durability and performance retention concepts are discussed. Other topics include engine diagnostics for performance retention and engine condition monitoring systems.390 pp19810022654
- Aircraft Engine EmissionsA conference on a aircraft engine emissions was held to present the results of recent and current work. Such diverse areas as components, controls, energy efficient engine designs, and noise and pollution reduction are discussed.464 pp19780003120
- Aircraft Engine Exhaust Nozzle System for Jet Noise ReductionThe aircraft exhaust engine nozzle system includes a fan nozzle to receive a fan flow from a fan disposed adjacent to an engine disposed above an airframe surface of the aircraft, a core nozzle disposed within the fan nozzle and receiving an engine core flow, and a pylon structure connected to the…10 pp20150003369
- Aircraft Engine Icing Event Avoidance and Mitigation Through Real-Time Simulation and ControlsA process for mitigating or proactively avoiding an aircraft engine icing event may include detecting ice crystals in the atmosphere using one or more sensors on board an aircraft in real time. The process may also include modulating one or more engine operating conditions to proactively change an…14 ppPatent Number: US-Patent-10,184,405
- Aircraft Engine Noise ReductionConference on reduction and suppression of aircraft engine noise326 ppNASA-SP-311
- Aircraft Engine Noise Research and Testing at the NASA Glenn Research CenterThe presentation will begin with a brief introduction to the NASA Glenn Research Center as well as an overview of how aircraft engine noise research fits within the organization. Some of the NASA programs and projects with noise content will be covered along with the associated goals of aircraft…43 pp20160014700
- Aircraft Engine Noise Research and Testing at the NASA Glenn Research CenterThe presentation will begin with a brief introduction to the NASA Glenn Research Center as well as an overview of how aircraft engine noise research fits within the organization. Some of the NASA programs and projects with noise content will be covered along with the associated goals of aircraft…41 pp20150023464
- Aircraft engine nozzleA variable area exit nozzle arrangement for an aircraft engine was a substantially reduced length and weight which comprises a number of longitudinally movable radial vanes and a number of fixed radial vanes. The movable radial vanes are alternately disposed with respect to the fixed radial vanes.…7 pp19800023884
- Aircraft Engine SystemsThis report outlines the detailed simulation of Aircraft Turbofan Engine. The objectives were to develop a detailed flow model of a full turbofan engine that runs on parallel workstation clusters overnight and to develop an integrated system of codes for combustor design and analysis to enable…22 pp20010108903
- Aircraft Engine SystemsThe objective is to develop the capability to numerically model the performance of gas turbine engines used for aircraft propulsion. This capability will provide turbine engine designers with a means of accurately predicting the performance of new engines in a system environment prior to building…6 pp20030068085
- Aircraft engine with inter-turbine engine frame supported counter rotating low pressure turbine rotorsAn aircraft gas turbine engine assembly includes an inter-turbine frame axially located between high and low pressure turbines. Low pressure turbine has counter rotating low pressure inner and outer rotors with low pressure inner and outer shafts which are at least in part rotatably disposed…14 ppPatent Number: US-PATENT-6,619,030
- Aircraft Flutter TestingWilmer Reed gained international recognition for his innovative research, contributions and patented ideas relating to flutter and aeroelasticity of aerospace vehicles at Langley Research Center. In the early 1980's, Reed retired from Langley and joined the engineering staff of Dynamic Engineering…1 pp20020076128
- Aircraft handling qualities dataAvailable information on weight and inertia, aerodynamic derivatives, control characteristics, and stability augmentation systems is documented for 10 representative contemporary airplanes. Data sources are given for each airplane. Flight envelopes are presented and dimensional derivatives,…352 pp19730003312
- Aircraft High-Lift Aerodynamic Analysis Using a Surface-Vorticity SolverThis study extends an existing semi-empirical approach to high-lift analysis by examining its effectiveness for use with a three-dimensional aerodynamic analysis method. The aircraft high-lift geometry is modeled in Vehicle Sketch Pad (OpenVSP) using a newly-developed set of techniques for building…15 pp20160007654
- Aircraft IcingNo abstract available34 pp20150010392
- Aircraft icing research at NASAResearch activity is described for: ice protection systems, icing instrumentation, experimental methods, analytical modeling for the above, and in flight research. The renewed interest in aircraft icing has come about because of the new need for All-Weather Helicopters and General Aviation…17 ppNASA-TM-82919
- Aircraft Icing Weather Data Reporting and Dissemination SystemThe long-term operational concept of this research is to develop an onboard aircraft system that assesses and reports atmospheric icing conditions automatically and in a timely manner in order to improve aviation safety and the efficiency of aircraft operations via improved real-time and forecast…75 ppNASA/CR-2002-211800
- Aircraft landing control systemUpon aircraft landing approach, flare path command signals of altitude, vertical velocity and vertical acceleration are generated as functions of aircraft position and velocity with respect to the ground. The command signals are compared with corresponding actual values to generate error signals…12 ppPatent Number: US-PATENT-4,357,661
- Aircraft Loss of Control: Research and Technology DirectionsAircraft loss of control is a leading cause of fatal accidents across all transport airplane and operational classes. Aircraft loss-of-control (LOC) accidents are highly complex in that they can result from numerous causal and contributing factors acting alone or (more often) in combination. Hence,…82 ppNF1676L-18905
- Aircraft Loss-of-Control: Analysis and Requirements for Future Safety-Critical Systems and Their ValidationLoss of control remains one of the largest contributors to fatal aircraft accidents worldwide. Aircraft loss-of-control accidents are complex, resulting from numerous causal and contributing factors acting alone or more often in combination. Hence, there is no single intervention strategy to…8 ppPaper No. 00299
- Aircraft Noise and Performance Data for a Notional Supersonic Business JetThe International Civil Aviation Organization recently completed a study that determined the global environmental impact of adding several hypothetical supersonic aircraft types to the existing subsonic fleet. NASA supported this study by designing a notional 55-tonne supersonic business jet. The…16 pp
- Aircraft Noise Reduction Subproject OverviewThe material presents highlights of propulsion and airframe noise research being completed for the Advanced Air Transport Technology Project. The basis of noise reduction plans along with representative work for the airframe, propulsion, and propulsion-airframe integration is discussed for the…28 ppGRC-E-DAA-TN31600
- Aircraft noise reduction technologyAircraft and airport noise reduction technology programs conducted by NASA are presented. The subjects discussed are: (1) effects of aircraft noise on individuals and communities, (2) status of aircraft source noise technology, (3) operational procedures to reduce the impact of aircraft noise, and…142 ppNASA-TM-X-68241
- Aircraft noise source and computer programs - User's guideThe application of computer programs for predicting the noise-time histories and noise contours for five types of aircraft is reported. The aircraft considered are: (1) turbojet, (2) turbofan, (3) turboprop, (4) V/STOL, and (5) helicopter. Three principle considerations incorporated in the design…112 pp19730023214
- Aircraft noise source and contour estimationCalculation procedures are presented for predicting the noise-time histories and noise contours (footprints) of five basic types of aircraft; turbojet, turofan, turboprop, V/STOL, and helicopter. The procedures have been computerized to facilitate prediction of the noise characteristics during…232 pp19730023213
- Aircraft performance on slippery runways in crosswindsAircraft performance on slippery runways in cross winds12 pp19650025611
- Aircraft Piston Engine Exhaust Emission SymposiumA 2-day symposium on the reduction of exhaust emissions from aircraft piston engines was held on September 14 and 15, 1976, at the Lewis Research Center in Cleveland, Ohio. Papers were presented by both government organizations and the general aviation industry on the status of government…388 pp19770010138
- Aircraft Pitch Control with Fixed Order LQ CompensatorsThis paper considers a given set of fixed order compensators for aircraft pitch control problem. By augmenting compensator variables to the original state equations of the aircraft, a new dynamic model is considered to seek a LQ controller. While the fixed order compensators can achieve a set of…4 ppURC97051
- Aircraft PropulsionThe Lewis Research Center is the National Aeronautics and Space Administration's principal field installation for research and development of advanced-aerospace-propulsion and power-generating systems. More specifically, a substantial part of the Center's activities is devoted to progress in the…465 pp19710009976
- Aircraft stability and control dataAircraft stability and control data138 ppNASA-CR-96008
- Aircraft System Identification from Multisine Inputs and Frequency ResponsesA frequency-domain approach is described for estimating parameters, such as stability and control derivatives, in aircraft flight dynamic models from measured input and output data. The approach uses orthogonal phase-optimized multisines for moving the aircraft control effectors, Fourier analysis…17 ppNF1676L-33221
- Aircraft System Noise of the NASA D8 Subsonic Transport ConceptA vehicle-level noise assessment has been performed for the NASA D8 (ND8) concept aircraft in the NASA Advanced Air Transport Technology Project portfolio. The NASA research-level Aircraft Noise Prediction Program was used to predict the noise from each source component on the ND8 to build up a…33 pp
- Aircraft Turbine Engine Control Research at NASA Glenn Research CenterThis lecture will provide an overview of the aircraft turbine engine control research at NASA (National Aeronautics and Space Administration) Glenn Research Center (GRC). A brief introduction to the engine control problem is first provided with a description of the current state-of-the-art control…37 pp20150000702
- Aircraft Turbine Engine Control Research at NASA Glenn Research CenterThis paper provides an overview of the aircraft turbine engine control research at the NASA Glenn Research Center (GRC). A brief introduction to the engine control problem is first provided with a description of the state-of-the-art control law structure. A historical aspect of engine control…36 pp20130013439
- Aircraft wing structural detail design (wing, aileron, flaps, and subsystems)The goal of this project was to design, in detail, the wing, flaps, and ailerons for a primary flight trainer. Integrated in this design are provisions for the fuel system, the electrical system, and the fuselage/cabin carry-through interface structure. This conceptual design displays the general…40 pp19940020492
- Aircraft wing structure detail designThe provisions of this project call for the design of the structure of the wing and carry-through structure for the Viper primary trainer, which is to be certified as a utility category trainer under FAR part 23. The specific items to be designed in this statement of work were Front Spar, Rear…36 pp19940020025
- Aircraft-Fuel-Tank Design for Liquid HydrogenSome of the considerations involved in the design of aircraft fuel tanks for liquid hydrogen are discussed herein. Several of the physical properties of metals and thermal insulators in the temperature range from ambient to liquid-hydrogen temperatures are assembled. Calculations based on these…28 pp19930088877
- Airfoil large eddy breakup devices for turbulent drag reductionIt was determined from the present LaRC experiments that tandem, airfoil-shaped large eddy breakup (LEBU) devices can reduce local skin friction as much as 30 percent with a recovery region extending more than 100 boundary layer thicknesses downstream. These airfoils experience near laminar skin…13 pp19880005574
- Airfoil section characteristics as affected by protuberancesThe drag and interference caused by protuberance from the surface of an airfoil have been determined in the NACA variable-density wind tunnel at a Reynolds number approximately 3,100,000. The effects of variations of the fore-and-aft position, height, and shape of the protuberance were measured by…16 ppNACA-TR-446
- Airfoil section data obtained in the NACA variable-density tunnel as affected by support interference and other correctionsThe results of an investigation of the effect of support interference on airfoil drag data obtained in the variable-density tunnel are presented. As a result of the support interference, previously published airfoil data from the variable-density tunnel have shown too large drag coefficients and…38 ppNACA-TR-669
- Airfoil section drag reduction at transonic speeds by numerical optimizationA practical procedure for the design of low drag, transonic airfoils is demonstrated. The procedure uses an optimization program, based on a gradient algorithm coupled with an aerodynamic analysis program, that solves the full, non-linear potential equation for transonic flow. The procedure is…34 pp19760009938
- Airframe Icing Research Gaps: NASA PerspectiveqCurrent Airframe Icing Technology Gaps: Development of a full 3D ice accretion simulation model. Development of an improved simulation model for SLD conditions. CFD modeling of stall behavior for ice-contaminated wings/tails. Computational methods for simulation of stability and control…14 pp
- Airloads and Wake Geometry Calculations for an Isolated Tiltrotor Model in a Wind TunnelTh tiltrotor aircraft configuration has the potential to revolutionize air transportation by providing an economical combination of vertical take-off and landing capability with efficient, high-speed cruise flight. To achieve this potential it is necessary to have validated analytical tools that…7 pp20030063077
- Airloads research study. Volume 2: Airload coefficients derived from wind tunnel dataThe development of B-1 aircraft rigid wind tunnel data for use in subsequent tasks of the Airloads Research Study is described. Data from the Rockwell International external structural loads data bank were used to generate coefficients of rigid airload shear, bending moment, and torsion at specific…112 pp19840009106
- Airloads, wakes, and aeroelasticityFundamental considerations regarding the theory of modeling of rotary wing airloads, wakes, and aeroelasticity are presented. The topics covered are: airloads and wakes, including lifting-line theory, wake models and nonuniform inflow, free wake geometry, and blade-vortex interaction; aerodynamic…54 pp19900012422
- Airplane landing gearThis report presents an investigation of the design and construction of various types of landing gears. Some of the items discussed include: chassises, wheels, shock absorbers (rubber disk and rubber cord), as well as oleopneumatic shock absorbers. Various types of landing gears are also discussed…40 ppNACA-TM-627
- Airvolt Aircraft Electric Propulsion Test StandDevelopment of an electric propulsion test stand that collects high-fidelity data of motor, inverter, and battery system efficiencies; thermal dynamics; and acoustics independent of manufacturer reported values will improve understanding of electric propulsion systems to be used in future aircraft.…19 pp20160001339
- Airworthiness considerations for STOL aircraftCriteria for satisfactory performance and handling qualities of powered-lift STOL transport aircraft72 pp19700006934
- Algorithms for output feedback, multiple-model, and decentralized control problemsThe optimal stochastic output feedback, multiple-model, and decentralized control problems with dynamic compensation are formulated and discussed. Algorithms for each problem are presented, and their relationship to a basic output feedback algorithm is discussed. An aircraft control design problem…24 pp
- Alleviation of whirl-flutter on a joined-wing tilt-rotor aircraft configuration using active controlsThe feasibility of using active controls to delay the onset of whirl-flutter on a joined-wing tilt rotor aircraft was investigated. The CAMRAD/JA code was used to obtain a set of linear differential equations which describe the motion of the joined-wing tilt-rotor aircraft. The hub motions due to…28 pp19940031929
- Altitude Effects on Thermal Ice Protection System Performance; A Study of an Alternative Simulation ApproachThe quest for more energy-efficient green aircraft, dictates that all systems, including the ice protection system (IPS), be closely examined for ways to reduce energy consumption and to increase efficiency. A thermal ice protection systems must protect the aircraft from the hazardous effects of…23 pp20150019750
- Altitude-Wind-Tunnel Investigation of the 19B-2, 19B-8, and 19XB-1 Jet-Propulsion Engines. II - Analysis of Turbine Performance of the 19B-8 EnginePerformance characteristics of the turbine in the 19B-8 jet propulsion engine were determined from an investigation of the complete engine in the Cleveland altitude wind tunnel. The investigation covered a range of simulated altitudes from 5000 to 30,000 feet and flight Mach numbers from 0.05 to…26 pp20090025286
- An Active Flow Circulation Controlled Flap Concept for General Aviation Aircraft ApplicationsA recent focus on revolutionary aerodynamic concepts has highlighted the technology needs of general aviation and personal aircraft. New and stringent restrictions on these types of aircraft have placed high demands on aerodynamic performance, noise, and environmental issues. Improved high lift…22 pp20020091887
- An AD100 implementation of a real-time STOVL aircraft propulsion systemA real-time dynamic model of the propulsion system for a Short Take-Off and Vertical Landing (STOVL) aircraft was developed for the AD100 simulation environment. The dynamic model was adapted from a FORTRAN based simulation using the dynamic programming capabilities of the AD100 ADSIM simulation…19 pp19910004144
- An adaptive learning control system for aircraftA learning control system is developed which blends the gain scheduling and adaptive control into a single learning system that has the advantages of both. An important feature of the developed learning control system is its capability to adjust the gain schedule in a prescribed manner to account…12 ppNASA-CR-146283
- An airfoil for general aviation applicationsA new airfoil, the NLF(1)-0115, has been recently designed at the NASA Langley Research Center for use in general-aviation applications. During the development of this airfoil, special emphasis was placed on experiences and observations gleaned from other successful general-aviation airfoils. For…11 pp19910003259
- An analysis of sound absorbing linings for the interior of the NASA Ames 80 x 120-foot wind tunnelIt is desirable to achieve low frequency sound absorption in the tests section of the NASA Ames 80X120-ft wind tunnel. However, it is difficult to obtain information regarding sound absorption characteristics of potential treatments because of the restrictions placed on the dimensions of the test…46 ppNASA-CR-177396
- An Analysis of the Autorotative Performance of a Helicopter Powered by Rotor-Tip Jet UnitsThe autorotative performance of an assumed helicopter was studied to determine the effect of inoperative jet units located at the rotor-blade tip on the helicopter rate of descent. For a representative ramjet design, the effect of the jet drag is to increase the minimum rate of descent of the…28 ppNACA-TN-2154
- An Analysis of the Strayton Engine, a Brayton and Stirling Cycle Recuperating EngineThis paper explores the novel Strayton engine concept. This engine combines the cycles of a Brayton engine with that of a Stirling engine to create a highly efficient recuperating gas turbine engine. In the explored case, both Brayton cycle and Stirling cycle engines are used to generate electrical…21 ppGRC-E-DAA-TN71720
- An analytical procedure for predicting the two-dimensional impact dynamics of spacecraft landing gearMathematical prediction model for landing dynamics of impacting struts, and trusses of lunar vehicle landing gear41 ppNASA-TN-D-4434
- AN ANALYTICAL STUDY OF EFFECTS OF SOME AIRPLANE AND LANDING-GEAR FACTORS ON THE RESPONSE TO RUNWAY ROUGHNESS WITH APPLICATION TO SUPERSONIC TRANSPORTSSupersonic transports - aircraft and landing-gear factors and response to runway roughness26 ppNASA-TN-D-1492
- An Approach to Designing Passive Self-Leveling Landing Gear with Application to the Lunar LanderOnce the lunar lander has touched down on the moon problems can occur if the crew module is not level. To mitigate, compliant landing gear provide a solution that would allow the module to be leveled once it has landed on some ground slope. The work presented here uses compliant joints, or…6 ppNF1676L-10191
- An Approach to Designing Passive Self-Leveling Landing Gear with Application to the Lunar LanderOnce the lunar lander has touched down on the moon problems can occur if the crew module is not level. To mitigate, compliant landing gear provide a solution that would allow the module to be leveled once it has landed on some ground slope. The work presented here uses compliant joints, or…8 pp
- An approach to the determination of aircraft handling qualities by using pilot transfer functionsTransfer functions of pilot for determining longitudinal aircraft controllability and pilot performance prediction30 pp19710005469
- An Assessment of Flap and Main Landing Gear Noise Abatement ConceptsA detailed assessment of the acoustic performance of several noise reduction concepts for aircraft flaps and landing gear is presented. Consideration is given to the best performing concepts within the suite of technologies that were evaluated in the NASA Langley Research Center 14- by 22-Foot…19 ppNF1676L-20192
- An assessment of General Aviation utilization of advanced avionics technologyNeeds of the general aviation industry for services and facilities which might be supplied by NASA were examined. In the data collection phase, twenty-one individuals from nine manufacturing companies in general aviation were interviewed against a carefully prepared meeting format. General aviation…40 pp19810005430
- An assessment of repeated loads on general aviation and transport aircraftStatistical analysis of repeated loads on general aviation and transport aircraft60 pp19680017958
- An Assessment of the Icing Blade and the SEA Multi-Element Sensor for Liquid Water Content Calibration of the NASA GRC Icing Research TunnelThe Icing Research Tunnel at NASA Glenn has recently switched from using the Icing Blade to using the SEA Multi-Element Sensor (also known as the multi-wire) for its calibration of cloud liquid water content. In order to peform this transition, tests were completed to compare the Multi-Element…17 ppGRC-E-DAA-TN33093
- An Assessment of the Icing Blade and the SEA Multi-Element Sensor for Liquid Water Content Calibration of the NASA GRC Icing Research TunnelThe Icing Research Tunnel at NASA Glenn has recently switched to from using the Icing Blade to using the SEA Multi-Element Sensor (also known as the multi-wire) for its calibration of cloud liquid water content. In order to perform this transition, tests were completed to compare the Multi-Element…22 ppGRC-E-DAA-TN31930
- An Assessment of the SEA Multi-Element Sensor for Liquid Water Content Calibration of the NASA GRC Icing Research TunnelThe NASA Glenn Icing Research tunnel has been using an Icing Blade technique to measure cloud liquid water content (LWC) since 1980. The IRT conducted tests with SEA Multi-Element sensors from 2009 to 2011 to assess their performance in measuring LWC. These tests revealed that the Multi-Element…16 ppGRC-E-DAA-TN23357
- An electric control for an electrohydraulic active control aircraft landing gearAn electronic controller for an electrohydraulic active control aircraft landing gear was developed. Drop tests of a modified gear from a 2722 Kg (6000 lbm) class of airplane were conducted to illustrate controller performance. The results indicate that the active gear effects a force reduction,…170 ppNASA-CR-3113
- An electronic control for an electrohydraulic active control landing gear for the F-4 aircraftA controller for an electrohydraulic active control landing gear was developed for the F-4 aircraft. A controller was modified for this application. Simulation results indicate that during landing and rollout over repaired bomb craters the active gear effects a force reduction, relative to the…95 ppNASA-CR-3552
- An Engine Research Program Focused on Low Pressure Turbine Aerodynamic PerformanceA comprehensive test program was performed in the Propulsion Systems Laboratory at the NASA Glenn Research Center, Cleveland Ohio using a highly instrumented Pratt and Whitney Canada PW 545 turbofan engine. A key objective of this program was the development of a high-altitude database on small,…6 pp20020087945
- An Evaluation of Automatic Control System Concepts for General Aviation AirplanesA piloted simulation study of automatic longitudinal control systems for general aviation airplanes has been conducted. These automatic control systems were designed to make the simulated airplane easy to fly for a beginning or infrequent pilot. Different control systems are presented and their…23 pp19910003257
- An evaluation of the handling qualities of seven general-aviation aircraftHandling qualities and stability and control characteristics of general-aviation aircraft66 ppNASA-TN-D-3726
- An Examination of Drag Reduction Mechanisms in Marine Animals, with Potential Applications to Uninhabited Aerial VehiclesPrevious engineering research and development has documented the plausibility of applying biomimetic approaches to aerospace engineering. Past cooperation between the Virginia Institute of Marine Science (VIMS) and NASA focused on the drag reduction qualities of the microscale dermal denticles of…7 pp20020046613
- An Examination of Handling Qualities Criteria for V/STOL AircraftA study has been undertaken to define hand-ling qualities criteria for V/STOL aircraft. With the current military requirements for helicopters and airplanes as a framework, modifications and additions were made for conversion to a preliminary set of V/STOL requirements using a broad background of…56 ppNASA-TN-D-331
- An Experimental Evaluation of Advanced Rotorcraft Airfoils in the NASA Ames Eleven-foot Transonic Wind TunnelFive full scale rotorcraft airfoils were tested in the NASA Ames Eleven-Foot Transonic Wind Tunnel for full scale Reynolds numbers at Mach numbers from 0.3 to 1.07. The models, which spanned the tunnel from floor to ceiling, included two modern baseline airfoils, the SC1095 and SC1094 R8, which…168 pp19880002258
- An Experimental Evaluation of Generalized Predictive Control for Tiltrotor Aeroelastic Stability Augmentation in Airplane Mode of FlightThe results of a joint NASA/Army/Bell Helicopter Textron wind-tunnel test to assess the potential of Generalized Predictive Control (GPC) for actively controlling the swashplate of tiltrotor aircraft to enhance aeroelastic stability in the airplane mode of flight are presented. GPC is an adaptive…15 pp
- An Experimental Investigation of an NACA 631-012 Airfoil Section with Leading-edge Suction Slots44 ppNACA-TN-1683
- An Experimental Investigation of Damaged Arresting Gear Tapes for the Langley Aircraft Landing Dynamics FacilityAn experimental investigation was performed on damaged arresting gear tapes at the Langley Aircraft Landing Dynamics Facility. The arrestment system uses five pairs of tapes to bring the test carriage to a halt. The procedure used to determine when to replace the tapes consists of a close…25 pp20000021500
- An experimental investigation of feasibility of a V/STOL test section in UWAL 8 x 12 wind tunnel by using a 1/8 scale model of the tunnelFeasibility of V/STOL test section in wind tunnel by using one eighth scale model of tunnel46 ppNASA-CR-69663
- An Experimental Investigation of Quadrotor Variations using NASA’s Multirotor Test BedGenerating multiple high-quality sets of rotor performance data is necessary to validate Vertical Take-Off and Landing (VTOL) aircraft performance prediction codes across a broad range of vehicle configurations. Many aircraft companies are actively pursuing multirotor vehicle configurations, which…17 pp
- An experimental investigation of the aerodynamics and cooling of a horizontally-opposed air-cooled aircraft engine installationA flight-test based research program was performed to investigate the aerodynamics and cooling of a horizontally-opposed engine installation. Specific areas investigated were the internal aerodynamics and cooling mechanics of the installation, inlet aerodynamics, and exit aerodynamics. The…152 pp19810013485
- An Experimental Investigation of the Effect of Propellers Used as Aerodynamic Brakes on Stability and ControlTests were made of a model representative of a single-engine tractor-type airplane for the purpose of determining the stability and control effects of a propeller used as an aerodynamic brake. The tests were made with single-and dual-rotation propellers to show the effect of type of propeller…100 ppNACA-ARR-5C01
- An experimental low Reynolds number comparison of a Wortmann FX67-K170 airfoil, a NACA 0012 airfoil and a NACA 64-210 airfoil in simulated heavy rainWind tunnel experiments were conducted on Wortmann FX67-K170, NACA 0012, and NACA 64-210 airfoils at rain rates of 1000 mm/hr and Reynolds numbers of 310,000 to compare the aerodynamic performance degradation of the airfoils and to attempt to identify the various mechanisms which affect performance…105 ppNASA-CR-181119
- An experimental simulation study of four crosswind landing gear conceptsAn experimental investigation was conducted in order to evaluate several crosswind landing-gear concepts which have a potential application to tricycle-gear-configured, short take-off and landing (STOL) aircraft landing at crab or heading angles up to 30 deg. In this investigation, the landing…58 ppNASA-TN-D-7864
- An experimental study of the aerodynamics of a NACA 0012 airfoil with a simulated glaze ice accretionAn experimental study was conducted in the Ohio State University subsonic wind tunnel to measure the detailed aerodynamic characteristics of an airfoil with a simulated glaze ice accretion. A NACA 0012 model with interchangeable leading edges and pressure taps every one percent chord was used.…326 ppNASA-CR-179897
- An experimental study of the effect of tail configuration on the spinning characteristics of general aviation aircraftThe feasibility of using static wind tunnel tests to obtain information about spin damping characteristics of an isolated general aviation aircraft tail was investigated. A representative tail section was oriented to the tunnel free streamline at angles simulating an equilibrium spin. A full range…183 pp19820011350
- An experimental study of transonic flow about a supercritical airfoil. Static pressure and drag data obtained from tests of a supercritical airfoil and an NACA 0012 airfoil at transonic speeds, supplementSurface static-pressure and drag data obtained from tests of two slightly modified versions of the original NASA Whitcomb airfoil and a model of the NACA 0012 airfoil section are presented. Data for the supercritical airfoil were obtained for a free-stream Mach number range of 0.5 to 0.9, and a…230 ppNASA-TM-81336-SUPPL
- An exploratory investigation of factors affecting the handling qualities of a rudimentary hingeless rotor helicopterFlight investigation of control qualities of rudimentary hingeless rotor helicopter42 ppNASA-TN-D-3418
- An Impulse-Momentum Method for Calculating Landing-Gear Contact Conditions in Eccentric LandingsAn impulse-momentum method for determining impact conditions for landing gears in eccentric landings is presented. The analysis is primarily concerned with the determination of contact velocities for impacts subsequent to initial touchdown in eccentric landings and with the determination of the…61 ppNACA-TN-2596
- An in-Time Aviation Safety Management System Concept of Operations and Modernization of the National Airspace SystemThe National Airspace System (NAS) is growing in complexity of aircraft, missions, and operations. In response, many organizations have published papers and concepts of operations (ConOps) for new and enhanced safety systems. The National Academies’ vision for an In-time Aviation Safety Management…32 pp
- An In-time Aviation Safety Management System Concept of Operations and Modernization of the National Airspace SystemThe National Airspace System (NAS) is growing in complexity of aircraft, missions, and operations. In response, many organizations have published papers and concepts of operations (ConOps) for new and enhanced safety systems. The National Academies’ vision for an In-time Aviation Safety Management…16 pp
- An Initial Study of the Fundamentals of Ice Crystal Icing Physics in the Nasa Propulsion Systems LaboratoryThis paper presents results from an initial study of the fundamental physics of ice-crystal ice accretion using the NASA Propulsion Systems Lab (PSL). Ice accretion due to the ingestion of ice-crystals is being attributed to numerous jet-engine power-loss events. The NASA PSL is an altitude…38 pp20170007924
- An Initial Study of the Fundamentals of Ice Crystal Icing Physics in the NASA Propulsion Systems LaboratoryThis presentation shows results from an initial study of the fundamental physics of ice-crystal ice accretion using the NASA Propulsion Systems Lab (PSL). Ice accretion due to the ingestion of ice-crystals is being attributed to numerous jet-engine power-loss events. The NASA PSL is an altitude…20 pp20170007302
- An Integrated Approach to Swept Wing Icing SimulationThis presentation describes the various elements of a simulation approach used to develop a database of ice shape geometries and the resulting aerodynamic performance data for a representative commercial transport wing model exposed to a variety of icing conditions. Methods for capturing full…28 ppGRC-E-DAA-TN44209
- An Integrated Approach to Swept Wing Icing SimulationThis paper describes the various elements of a simulation approach used to develop a database of ice shape geometries and the resulting aerodynamic performance data for a representative commercial transport wing model exposed to a variety of icing conditions. This effort included testing in the…15 ppGRC-E-DAA-TN44244
- An Integrated Architecture for Aircraft Engine Performance Monitoring and Fault Diagnostics: Engine Test ResultsThis paper presents a model-based architecture for performance trend monitoring and gas path fault diagnostics designed for analyzing streaming transient aircraft engine measurement data. The technique analyzes residuals between sensed engine outputs and model predicted outputs for fault detection…18 pp20150000899
- An Integrated Architecture for Aircraft Engine Performance Monitoring and Fault Diagnostics: Engine Test ResultsThis paper presents a model-based architecture for performance trend monitoring and gas path fault diagnostics designed for analyzing streaming transient aircraft engine measurement data. The technique analyzes residuals between sensed engine outputs and model predicted outputs for fault detection…11 pp20140017055
- An Integrated Architecture for Aircraft Engine Performance Monitoring and Fault Diagnostics: Engine Test ResultsThis paper presents a model-based architecture for performance trend monitoring and gas path fault diagnostics designed for analyzing streaming transient aircraft engine measurement data. The technique analyzes residuals between sensed engine outputs and model predicted outputs for fault detection…25 pp20140016832
- An Interim Report on the Stability and Control of Tailless AirplanesProblems relating to the stability and control of tailless airplanes are discussed in consideration of contemporary experience and practice.16 ppNACA/TR-796
- An investigation of a stoppable helicopter rotor with circulation controlA stoppable helicopter rotor with circulation control was investigated in the Ames 40 by 80 foot wind tunnel. The model was tested as a rotating wing, a fixed wing, and during transition start/stop sequences. The capability of the model's control system to maintain pitch and roll moment balance…370 ppNASA-TM-81218
- An Investigation of Glaciated Cloud Capabilities in the NASA Glenn Icing Research TunnelIn 2015 the FAA added Appendix D to Part 33 engine certification requirements that included Mixed Phase and Ice Crystal Icing to aircraft engine certification. Replicating the ice crystal environment that is seen in nature has proven to be a challenge, which multiple engine ground testing…18 ppGRC-E-DAA-TN58311
- An Investigation of Large Tilt-Rotor Hover and Low Speed Handling QualitiesA piloted simulation experiment conducted on the NASA-Ames Vertical Motion Simulator evaluated the hover and low speed handling qualities of a large tilt-rotor concept, with particular emphasis on longitudinal and lateral position control. Ten experimental test pilots evaluated different…19 pp20110014345
- An Investigation of Large Tilt-Rotor Short-Term Attitude Response Handling Qualities Requirements in HoverA piloted simulation investigation was conducted using the NASA Ames Vertical Motion Simulator to study the impact of pitch, roll and yaw attitude bandwidth and phase delay on handling qualities of large tilt-rotor aircraft. Multiple bandwidth and phase delay pairs were investigated for each axis.…22 pp20100026614
- An investigation of separate surface stability augmentation systems for general aviation aircraftThe status of a project to develop and evaluate separate surface stability augmentation systems for general aviation aircraft is discussed. The electrical design, roll heading hold is described and schematic diagrams and an operational description are provided. The flight tests program is…82 pp19740013534
- An investigation of the dynamic stability and control characteristics for a transport cruising at a mach number of 3Dynamic lateral stability and control for supersonic transport38 ppNASA-TN-D-2483
- An investigation of the effects of pitch-roll (de)coupling on helicopter handling qualitiesAn extensive investigation of the effects of pitch-roll coupling on helicopter handling qualities was performed by the U.S. Army and Deutsche Forschungsanstalt fur Luft- und Raumfahrt (DLR), using a NASA ground-based and a DLR in-flight simulator. Over 90 different coupling configurations were…126 pp19950020353
- An investigation of the effects of roll-spiral coupling on the lateral-directional handling qualities of a STOL subsonic transportRoll-spiral coupling effects on lateral and directional handling qualities of STOL subsonic transport72 pp19690030716
- An investigation of the feasibility of active boundary layer thickening for aircraft drag reductionThe feasibility of using a forward mounted windmilling propeller to extract momentum from the flow around an axisymmetric body to reduce total drag has been studied. Numerical calculations indicate that a net drag reduction is possible when the energy extracted is returned to an aft mounted pusher…17 pp19860018592
- An investigation of the increase in vortex induced rolling moment associated with landing gear wakeFlight tests were conducted to verify the results found in ground base facilities of the effect of span lift load variation as well as the vortex attentuation of the high energy jet engine exhaust through proper thrust programming. During these flight tests a large increase in vortex strength was…20 ppNASA-TM-X-72786
- An Investigation of the Use of Bandwidth Criteria for Rotorcraft Handling-Qualities SpecificationsThe objective of this study was to investigate bandwidth concepts for deriving rotorcraft handling-qualities criteria from data obtained in two simulator experiments conducted at the Aeromechanics Laboratory. The first experiment was an investigation of the effects of helicopter…16 pp19860008849
- An investigation on the effect of second-order additional thickness distributions to the upper surface of an NACA 64 sub 1-212 airfoilAn investigation was conducted on a CDC 7600 digital computer to determine the effects of additional thickness distributions to the upper surface of an NACA 64 sub 1 - 212 airfoil. Additional thickness distributions employed were in the form of two second-order polynomial arcs which have a…48 ppNASA-CR-137701
- An investigation on the effect of second-order additional thickness distributions to the upper surface of an NACA 64-206 airfoilAn investigation was conducted on a CDC 7600 digital computer to determine the effects of additional thickness distributions to the upper surface of an NACA 64-206 airfoil. Additional thickness distributions employed were in the form of two second-order polynomial arcs which have a specified…33 ppNASA-CR-137702
- An Online Resource for Flight Test Safety PlanningA viewgraph presentation describing an online database for flight test safety techniques is shown. The topics include: 1) Goal; 2) Test Hazard Analyses; 3) Online Database Background; 4) Data Gathering; 5) NTPS Role; 6) Organizations; 7) Hazard Titles; 8) FAR Paragraphs; 9) Maneuver Name; 10)…31 pp20070017453
- An overview of a model rotor icing test in the NASA Lewis Icing Research TunnelDuring two entries in late 1989, a heavily instrumented sub-scale model of a helicopter main rotor was tested in the NASA LeRC Icing Research Tunnel (IRT). The results of this series of tunnel tests were published previously. After studying the results from the 1989 test and comparing them to…24 pp19940018826
- An overview of aerospace gas turbine technology of relevance to the development of the automotive gas turbine engineTechnology areas related to gas turbine propulsion systems with potential for application to the automotive gas turbine engine are discussed. Areas included are: system steady-state and transient performance prediction techniques, compressor and turbine design and performance prediction programs…52 pp19780005119
- An Overview of Controls and Flying Qualities Technology on the F/A-18 High Alpha Research VehicleThe NASA F/A-18 High Alpha Research Vehicle (HARV) has been the flight test bed of a focused technology effort to significantly increase maneuvering capability at high angles of attack. Development and flight test of control law design methodologies, handling qualities metrics, performance…27 pp19990064010
- An Overview of Flight Test Results for a Formation Flight AutopilotThe first flight test phase of the NASA Dryden Flight Research Center Autonomous Formation Flight project has successfully demonstrated precision autonomous station-keeping of an F/A-18 research airplane with a second F/A-18 airplane. Blended inertial navigation system (INS) and global positioning…19 pp20030005820
- An Overview of Landing Gear DynamicsOne of the problems facing the aircraft community is landing gear dynamics, especially shimmy and brake-induced vibration. Shimmy and brake-induced vibrations can lead to accidents due to excessive wear and shortened life of gear parts and contribute to pilot and passenger discomfort. To increase…20 ppNASA/TM-1999-209143
- An overview of NASA research on positive displacement general-aviation enginesThe research and technology program related to improved and advanced general aviation engines is described. Current research is directed at the near-term improvement of conventional air-cooled spark-ignition piston engines and at future alternative engine systems based on all-new spark-ignition…10 pp
- An Overview of NASA Research on Positive Displacement Type General Aviation EnginesThe general aviation positive displacement engine program encompassing conventional, lightweight diesel, and rotary combustion engines is described. Lean operation of current production type spark ignition engines and advanced alternative engine concepts are emphasized.40 pp19790023039
- An overview of the quiet short-haul research aircraft programAn overview of the Quiet Short Haul Research Aircraft (QSRA) Program is presented, with special emphasis on its propulsion and acoustic aspects. A description of the NASA technical participation in the program including wind tunnel testing, engine ground tests, and advanced aircraft simulation is…41 pp19790002863
- An unsteady helicopter rotor: Fuselage interaction analysisA computational method was developed to treat unsteady aerodynamic interactions between a helicopter rotor, wake, and fuselage and between the main and tail rotors. An existing lifting line prescribed wake rotor analysis and a source panel fuselage analysis were coupled and modified to predict…130 ppNASA-CR-4178
- Analyses and tests of the B-1 aircraft structural mode control systemAnalyses and flight tests of the B-1 structural mode control system (SMCS) are presented. Improvements in the total dynamic response of a flexible aircraft and the benefits to ride qualities, handling qualities, crew efficiency, and reduced dynamic loads on the primary structures, were…276 pp19800006814
- Analysis and correlation of the test data from an advanced technology rotor systemComparisons were made of the performance and blade vibratory loads characteristics for an advanced rotor system as predicted by analysis and as measured in a 1/5 scale model wind tunnel test, a full scale model wind tunnel test and flight test. The accuracy with which the various tools available at…171 ppNASA-CR-3714
- Analysis of a Stretched Derivative Aircraft with Open Rotor PropulsionResearch into advanced, high-speed civil turboprops received significant attention during the 1970s and 1980s when fuel efficiency was the driving focus of U.S. aeronautical research. But when fuel prices declined sharply there was no longer sufficient motivation to continue maturing the…8 pp20150022167
- Analysis of Aviation Safety Reporting System Incident Data Associated with the Technical Challenges of the System-Wide Safety and Assurance Technologies ProjectThe Aviation Safety Program (AvSP) System-Wide Safety and Assurance Technologies (SSAT) Project asked the AvSP Systems and Portfolio Analysis Team to identify SSAT-related trends. SSAT had four technical challenges: advance safety assurance to enable deployment of NextGen systems; automated…80 ppNASA/TM-2015-217899
- Analysis of boundary-layer transition on X-152-2 research airplaneSurface roughness effects on boundary layer transition indicated by thermocouple data from X-15 aircraft flight12 pp19660020887
- Analysis of Control Strategies for Aircraft Flight Upset RecoveryThis paper proposes a framework for studying the ability of a control strategy, consisting of a control law and a command law, to recover an aircraft from ight conditions that may extend beyond the normal ight envelope. This study was carried out (i) by evaluating time responses of particular ight…31 ppNF1676L-14058
- Analysis of Experimental Ice Accretion Data and Assessment of a Thermodynamic Model During Ice Crystal IcingThis paper evaluates a thermodynamic ice crystal icing model that has been previously presented to describe the possible mechanisms of icing within the core of a turbofan jet engine. The model functions between two distinct ice accretions based on a surface energy balance: freeze-dominated icing…17 ppGRC-E-DAA-TN66908
- Analysis of flexible aircraft longitudinal dynamics and handling qualities. Volume 1: Analysis methodsAs aircraft become larger and lighter due to design requirements for increased payload and improved fuel efficiency, they will also become more flexible. For highly flexible vehicles, the handling qualities may not be accurately predicted by conventional methods. This study applies two analysis…111 pp19850026889
- Analysis of flexible aircraft longitudinal dynamics and handling qualities. Volume 2: DataTwo analysis methods are applied to a family of flexible aircraft in order to investigate how and when structural (especially dynamic aeroelastic) effects affect the dynamic characteristics of aircraft. The first type of analysis is an open loop modal analysis technique. This method considers the…240 pp19850026890
- Analysis of general aviation single-pilot IFR incident data obtained from the NASA aviation safety reporting systemData obtained from the NASA Aviation Safety Reporting System (ASRS) data base were used to determine problems in general aviation single pilot IFR operations. The data examined consisted of incident reports involving flight safety in the National Aviation System. Only those incidents involving…20 ppNASA-TM-80206
- Analysis of general aviation single-pilot IFR incident data obtained from the NASA Aviation Safety Reporting SystemAn analysis of incident data obtained from the NASA Aviation Safety Reporting System (ASRS) has been made to determine the problem areas in general aviation single-pilot IFR (SPIFR) operations. The Aviation Safety Reporting System data base is a compilation of voluntary reports of incidents from…7 pp
- Analysis of Handling Qualities Design Criteria for Active Inceptor Force-Feel CharacteristicsThe force-feel system characteristics of the cyclic inceptors of most helicopters are set based on the characteristics of the mechanical components in the control system (mass, springs, friction dampers, etc.). For these helicopters, the force-feel characteristics typically remain constant over the…6 pp20130013798
- Analysis of Landing-Gear BehaviorThis report presents a theoretical study of the behavior of the conventional type of oleo-pneumatic landing gear during the process of landing impact. The basic analysis is presented in a general form and treats the motions of the landing gear prior to and subsequent to the beginning of shock-strut…50 ppNACA-TR-1154
- Analysis of Low-Speed Stall Aerodynamics of a Swept Wing with Seamless FlapsComputational fluid dynamics (CFD) analysis was conducted to study the low-speed stall aerodynamics of a Gulfstream G-III airplane (Gulfstream Aerospace Corporation, Savannah, Georgia) swept wing modified with an experimental seamless, compliant flap called the Adaptive Compliant Trailing Edge…9 pp20160007772
- Analysis of Performance of Jet Engine from Characteristics of Components I : Aerodynamic and Matching Characteristics of Turbine Component Determined with Cold AirThe performance of the turbine component of an NACA research jet engine was investigated with cold air. The interaction and the matching of the turbine with the NACA eight-stage compressor were computed with the combination considered as a jet engine. The over-all performance of the engine was then…24 ppNACA-TR-878
- Analysis of ram-jet engine performance including effects of component changesCalculated design-point performance of ram-jet engines using JP-4 fuel is presented for a wide range of engine total-temperature ratios and combustion-chamber-inlet Mach numbers for flight numbers from 1.5 to 4.0. The results include engine thrust, drag, fuel consumption, and area ratios. Data are…47 ppNACA-RM-E56D20
- Analysis of Supercooled Large Drop Velocity Measurement in the NASA Icing Research TunnelAn experiment was conducted in the Icing Research Tunnel (IRT) at the NASA Glenn Research Center to measure the velocity of supercooled large drops (SLD) in the test section of the tunnel. Previous experiments in the IRT suggested that supercooled large drops passing through the test section of the…24 pp
- Analysis of technology requirements and potential demand for general aviation avionics systems for operation in the 1980'sAvionics systems are identified which promise to reduce economic constraints and provide significant improvements in performance, operational capability and utility for general aviation aircraft in the 1980's.35 pp19750008482
- Analysis of the free-tip rotor wind-tunnel test resultsThe results from a wind tunnel test of a small scale free-tip rotor are analyzed. The free-tip rotor has blade tips that are free to weathervane into the tip's relative wind, thus producing a more uniform lift around the azimuth. The free-tip assembly, which includes the controller, functioned…70 ppNASA-TM-86751
- Analysis of the longitudinal handling qualities and pilot-induced-oscillation tendencies of the High-Angle-of-Attack Research Vehicle (HARV)The NASA High-Angle-of Attack Research Vehicle (HARV), a modified F-18 aircraft, experienced handling qualities problems in recent flight tests at NASA Dryden Research Center. Foremost in these problems was the tendency of the pilot-aircraft system to exhibit a potentially dangerous phenomenon…1 pp19950016877
- Analysis of the wind tunnel test of a tilt rotor power force modelTwo series of wind tunnel tests were made to determine performance, stability and control, and rotor wake interaction on the airframe, using a one-tenth scale powered force model of a tilt rotor aircraft. Testing covered hover (IGE/OCE), helicopter, conversion, and airplane flight configurations.…140 ppNASA-CR-137529
- Analysis of two dimensional inviscid model of jet impingement under vertical-takeoff airplaneAnalysis of two dimensional inviscid model jet impingement under verticle takeoff airplane37 pp19690020101
- Analysis of Wind Tunnel Lateral Oscillatory Data of the F-16XL AircraftStatic and dynamic wind tunnel tests were performed on an 18% scale model of the F-16XL aircraft. These tests were performed over a wide range of angles of attack and sideslip with oscillation amplitudes from 5 deg. to 30 deg. and reduced frequencies from 0.073 to 0.269. Harmonic analysis was used…114 ppNASA/TM-2004-213246
- Analysis of wind tunnel test results for a 9.39-per cent scale model of a VSTOL fighter/attack aircraft. Volume 1: Study overviewThe ability of current methodologies to accurately predict the aerodynamic characteristics identified as uncertainties was evaluated for two aircraft configurations. The two wind tunnel models studied horizontal altitude takeoff and landing V/STOL fighter aircraft derivatives.110 ppNASA-CR-152391-VOL-1
- Analysis of wind tunnel test results for a 9.39-per cent scale model of a VSTOL fighter/attack aircraft. Volume 2: Evaluation of prediction methodologiesAn evaluation of current prediction methodologies to estimate the aerodynamic uncertainties identified for the E205 configuration is presented. This evaluation was accomplished by comparing predicted and wind tunnel test data in three major categories: untrimmed longitudinal aerodynamics; trimmed…144 ppNASA-CR-152391-VOL-2
- Analysis of wing truss stresses including the effect of redundanciesAirplane wing trusses are generally designed to contain redundant members (stagger wires and external drag wires) which, according to common practice, are not taken into account in calculations, so as to simplify the stress analysis by rendering the structure statically determinate. A more accurate…20 ppNACA-TR-92
- Analytic development of improved supersonic cruise aircraft based on wind tunnel dataData obtained from the MDC/NASA cooperative wing tunnel program were used to develop empirical corrections to theory. These methods were then used to develop a 2.2M supersonic cruise aircraft configuration with a cruise trimmed maximum L/D of 10.2. The empirical corrections to the theory are…23 pp
- Analytic investigation of helicopter rotor blade appended aeroelastic devicesAnalytic evaluations of four different passive aeroelastic devices appended to helicopter rotor blades are presented. The devices consist of a passive tuned tab, a control coupled tab, an all-flying tip and a harmonic dilational airfoil tip. Each device was conceived for improving either…95 ppNASA-CR-166525
- Analytic Methods in Aircraft AerodynamicsAnalyses of aircraft aerodynamic characteristics751 pp19700012046
- Analytical and simulator study of advanced transportAn analytic methodology, based on the optimal-control pilot model, was demonstrated for assessing longitidunal-axis handling qualities of transport aircraft in final approach. Calibration of the methodology is largely in terms of closed-loop performance requirements, rather than specific vehicle…85 pp19820020422
- Analytical determination of the take-off performance of some representative supersonic transport configurationsTakeoff performance of supersonic transport configurations26 ppNASA-TN-D-2308
- Analytical evaluation of effect of equivalence ratio inlet-air temperature and combustion pressure on performance of several possible ram-jet fuelsThe results of an analytical investigation of the theoretical air specific impulse performance and adiabatic combustion temperatures of several possible ram-jet fuels over a range of equivalence ratios, inlet-air temperatures, and combustion pressures, is presented herein. The fuels include…60 ppNACA-RM-E53G14
- Analytical evaluation of tilting proprotor wind tunnel test requirementsSpecific test requirements related to the wind tunnel testing of the XV-15 advanced tilt rotor research aircraft were determined. The following analytical tools were developed: (1) digital simulation of the XV-15, incorporating a simplified tunnel support model, control system loop, measurement…140 ppNASA-CR-137826
- Analytical investigation of a helicopter rotor driven and controlled by a jet flapDriving and controlling helicopter rotor by deflectable jet flap - theoretical study of jet-flat rotor characteristics50 ppNASA-TN-D-3028
- Analytical investigation of ram-jet-engine performance in flight Mach number range from 3 to 7An analytical investigation was made of the performance of isolated ram-jet engines in the flight Mach number range from 3 to 7 for two types of diffuser, a high-efficiency diffuser, and a normal-shock diffuser. The fuel was assumed to be a hydrocarbon similar to gasoline. The conclusions reached…30 ppNACA-RM-E51H02
- Analytical investigation of the landing dynamics of a large airplane with a load-control system in the main landing gearThe results of an evaluation of an active load-control landing gear computer program (ACOLAG) for predicting the landing dynamics of airplanes with passive and active main gears are presented. ACOLAG was used in an analytical investigation of the landing dynamics of a large airplane with both…86 ppNASA-TP-1555
- Analytical Models for Rotor Test Module, Strut, and Balance Frame Dynamics in the 40 by 80 Ft Wind TunnelA mathematical model is developed for the dynamics of a wind tunnel support system consisting of a balance frame, struts, and an aircraft or test module. Data are given for several rotor test modules in the Ames 40 by 80 ft wind tunnel. A model for ground resonance calculations is also described.18 ppNASA-TM-X-73153
- Analytical study of ride smoothing benefits of control system configurations optimized for pilot handling qualitiesAn analytical study was conducted to evaluate the relative improvements in aircraft ride qualities that resulted from utilizing several control law configurations that were optimized for pilot handling qualities only. The airplane configuration used was an executive jet transport in the approach…61 pp19780010133
- Angled Core Gas Turbine Engine MountingA propulsion system for an aircraft includes first and second turbine engines mounted within a fuselage of the aircraft. The first turbine engine includes a first engine core that drives a first propulsor disposed about a first propulsor axis. The second turbine engine includes a second engine core…8 ppPatent Application Number: US-Patent-Appl-SN-14/440,698
- ANOPP Landing Gear Noise Prediction Comparisons to Model-scale DataThe NASA Aircraft NOise Prediction Program (ANOPP) includes two methods for computing the noise from landing gear: the "Fink" method and the "Guo" method. Both methods have been predominately validated and used to predict full-scale landing gear noise. The two methods are compared, and their…19 ppAIAA-2007-3459
- Apollo experience report: Lunar module landing gear subsystemThe development of the lunar module landing gear subsystem through the Apollo 11 lunar landing mission is presented. The landing gear design evolved from the design requirement, which had to satisfy the structural, mechanical, and landing performance constraints of the vehicle. Extensive analyses…60 ppNASA-TN-D-6850
- Apollo Lunar Module Landing GearThe Apollo lunar module landing-gear flight-performance results and three principal gear development problems are discussed. In evaluating the lunar module touchdown performance, strut stroking and toppling stability are the prime factors and are governed primarily by touchdown velocity and surface…11 pp
- Application and Evaluation of Control Modes for Risk-Based Engine Performance EnhancementsThe engine control system for civil transport aircraft imposes operational limits on the propulsion system to ensure compliance with safety standards. However, during certain emergency situations, aircraft survivability may benefit from engine performance beyond its normal limits despite the…28 ppNASA/TM-2015-218452
- Application and Evaluation of Control Modes for Risk-Based Engine Performance EnhancementsThe engine control system for civil transport aircraft imposes operational limits on the propulsion system to ensure compliance with safety standards. However, during certain emergency situations, aircraft survivability may benefit from engine performance beyond its normal limits despite the…19 ppGRC-E-DAA-TN16125
- Application and Evaluation of Control Modes for Risk-Based Engine Performance EnhancementsThe engine control system for civil transport aircraft imposes operational limits on the propulsion system to ensure compliance with safety standards. However, during certain emergency situations, aircraft survivability may benefit from engine performance beyond its normal limits despite the…24 ppGRC-E-DAA-TN16656
- Application of a Comprehensive Analytical Model of Rotor Aerodynamics and Dynamics (CAMRAD) to the McDonnell Douglas AH-64A helicopterA model of the AH-64A helicopter was generated in a Comprehensive Analytical Model of Rotorcraft Aerodynamics and Dynamics (CAMRAD) in an effort to validate its analytical capabilities for modeling a current advanced Army helicopter. The initial phase of the effort involved the generation of CAMRAD…62 ppNASA-CR-177455
- Application of active control landing gear technology to the A-10 aircraftTwo concepts which reduce the A-10 aircraft's wing/gear interface forces as a result of applying active control technology to the main landing gear are described. In the first concept, referred to as the alternate concept a servovalve in a closed pressure control loop configuration effectively…132 ppNASA-CR-166104
- Application of active controls technology to aircraft bide smoothing systemsA critical review of past efforts in the design and testing of ride smoothing and gust alleviation systems is presented. Design trade offs involving sensor types, choice of feedback loops, human comfort, and aircraft handling-qualities criteria are discussed. Synthesis of a system designed to…208 pp19760007050
- Application of Bounded Linear Stability Analysis Method for Metrics-Driven Adaptive ControlThis paper presents the application of Bounded Linear Stability Analysis (BLSA) method for metrics-driven adaptive control. The bounded linear stability analysis method is used for analyzing stability of adaptive control models, without linearizing the adaptive laws. Metrics-driven adaptive control…11 ppARC-E-DAA-TN-289
- Application of composites to helicopter airframe and landing gear structuresA preliminary design study has indicated that advanced composite helicopter airframe structures can provide significant system cost advantages in the 1980's. A seven percent increase in productivity and a five percent reduction in life cycle cost are projected. Due to their complexity, landing gear…146 ppNASA-CR-112333
- Application of Forebody Strakes for Directional Stability and Control of Transport AircraftA brief overview of a cooperative NASA/Boeing research effort, Strake Technology Research Application to Transport Aircraft (STRATA), intended to explore the potential of applying forebody strake technology to transport aircraft configurations for directional stability and control at low angles of…9 ppAIAA Paper 98-4448
- Application of frequency domain handling qualities criteria to the longitudinal landing taskUnder NASA sponsorship, an in-flight simulation of the longitudinal handling qualities of several configurations for the approach and landing tasks was performed on the USAF/AFWAL Total In-Flight Simulator by the Calspan Corporation. The basic configuration was a generic transport airplane with…17 pp19850024811
- Application of FUN3D Solver for Aeroacoustics Simulation of a Nose Landing Gear ConfigurationNumerical simulations have been performed for a nose landing gear configuration corresponding to the experimental tests conducted in the Basic Aerodynamic Research Tunnel at NASA Langley Research Center. A widely used unstructured grid code, FUN3D, is examined for solving the unsteady flow field…18 pp20110012467
- Application of nonlinear feedback control theory to supermaneuverable aircraftControlled flight at extremely high angles of attack, far exceeding the stall angle, and/or at high angular rates is sometimes referred to as supermaneuvering flight. The objective was to examine methods for design of control laws for aircraft performing supermaneuvers. Since the equations which…7 ppNASA-CR-190336
- Application of parameter estimation to aircraft stability and control: The output-error approachThe practical application of parameter estimation methodology to the problem of estimating aircraft stability and control derivatives from flight test data is examined. The primary purpose of the document is to present a comprehensive and unified picture of the entire parameter estimation process…177 ppNASA-RP-1168
- Application of stochastic robustness to aircraft control systemsGuaranteeing robustness has long been an important design objective of control system analysis. Stochastic robustness is a simple numerical procedure that can be used to measure and gain insight into robustness properties associated with linear control systems. In the realm of aircraft control…22 pp
- Application of the model technique to a variable-stability helicopter for simulation of vtol handling qualitiesApplication of computer model technique to variable-stability helicopter for in-flight simulation of VTOL handling qualities22 pp19650025398
- Application of the Tool for Turbine Engine Closed-loop Transient Analysis (TTECTrA) for Dynamic Systems AnalysisSystems analysis involves steady-state simulations of combined components to evaluate the steady-state performance, weight, and cost of a system; dynamic considerations are not included until later in the design process. The Dynamic Systems Analysis task, under NASAs Fixed Wing project, is…9 pp20140011336
- Application of the Tool for Turbine Engine Closed-loop Transient Analysis (TTECTrA) for Dynamic Systems AnalysisSystems analysis involves steady-state simulations of combined components to evaluate the steady-state performance, weight, and cost of a system; dynamic considerations are not included until later in the design process. The Dynamic Systems Analysis task, under NASAs Fixed Wing project, is…21 pp20140016753
- Application of the Tool for Turbine Engine Closed-Loop Transient Analysis (TTECTrA) for Dynamic Systems AnalysisThe aircraft engine design process seeks to achieve the best overall system-level performance, weight, and cost for a given engine design. This is achieved by a complex process known as systems analysis, where steady-state simulations are used to identify trade-offs that should be balanced to…16 pp20150011439
- Application of tire dynamics to aircraft landing gear design analysisThe tire plays a key part in many analyses used for design of aircraft landing gear. Examples include structural design of wheels, landing gear shimmy, brake whirl, chatter and squeal, complex combination of chatter and shimmy on main landing gear (MLG) systems, anti-skid performance, gear walk,…23 pp
- Application of variable structure system theory to aircraft flight controlThe current status of research on the application of variable structure system (VSS) theory to design aircraft flight control systems is summarized. Two aircraft types are currently being investigated: the Augmentor Wing Jet STOL Research Aircraft (AWJSRA), and AV-8A Harrier. The AWJSRA design…43 ppNASA-CR-164321
- Application of Wind Tunnel Free-Flight Technique for Wake Vortex EncountersA wind tunnel investigation was conducted in the Langley 30- by 60-Foot Tunnel to assess the free-flight test technique as a tool in research on wake vortex encounters. A typical 17.5-percent scale business-class jet airplane model was flown behind a stationary wing mounted in the forward portion…74 ppNASA-TP-3672
- Applications of Computational Methods for Dynamic Stability and Control DerivativesInitial steps in the application o f a low-order panel method computational fluid dynamic (CFD) code to the calculation of aircraft dynamic stability and control (S&C) derivatives are documented. Several capabilities, unique to CFD but not unique to this particular demonstration, are identified and…17 ppAIAA Paper 2004-0377
- Applications of flight control system methods to an advanced combat rotorcraftAdvanced flight control system design, analysis, and testing methodologies developed at the Ames Research Center are applied in an analytical and flight test evaluation of the Advanced Digital Optical Control System (ADOCS) demonstrator. The primary objectives are to describe the knowledge gained…62 pp19900002436
- Applied aerodynamics: Challenges and expectationsAerospace is the leading positive contributor to this country's balance of trade, derived largely from the sale of U.S. commercial aircraft around the world. This powerfully favorable economic situation is being threatened in two ways: (1) the U.S. portion of the commercial transport market is…22 pp19930015902
- Approach Considerations in Aircraft with High-Lift Propeller SystemsNASA's research into distributed electric propulsion (DEP) includes the design and development of the X-57 Maxwell aircraft. This aircraft has two distinct types of DEP: wingtip propellers and high-lift propellers. This paper focuses on the unique opportunities and challenges that the high-lift…18 pp20170005869
- Approach for Structurally Clearing an Adaptive Compliant Trailing Edge Flap for FlightThe Adaptive Compliant Trailing Edge (ACTE) flap was flown on the National Aeronautics and Space Administration (NASA) Gulfstream GIII testbed at the NASA Armstrong Flight Research Center. This smoothly curving flap replaced the existing Fowler flaps creating a seamless control surface. This…20 pp20150019388
- Approach for Structurally Clearing an Adaptive Compliant Trailing Edge Flap for FlightThe Adaptive Compliant Trailing Edge (ACTE) flap was flown on the NASA Gulfstream GIII test bed at the NASA Armstrong Flight Research Center. This smoothly curving flap replaced the existing Fowler flaps creating a seamless control surface. This compliant structure, developed by FlexSys Inc. in…20 ppDFRC-E-DAA-TN26324
- Approach path control for powered-lift STOL aircraftA flight control system concept is defined for approach flightpath control of an augmentor wing (or similar) powered-lift STOL configuration. The proposed STOL control concept produces aircraft transient and steady-state control responses that are familiar to pilots of conventional jet transports,…100 pp19730015335
- Approach to Modeling Boundary Layer Ingestion Using a Fully Coupled Propulsion-RANS ModelAlthough boundary layer ingestion (BLI), or wake ingestion, is commonly applied in marine propulsion applications, it has not yet seen wide-spread adoption in aircraft applications. However, recent studies have predicted that BLI offers a potential for a 10 reduction in aircraft fuel burn, even on…20 pp20170005216
- Approach to Modeling Boundary Layer Ingestion Using a Fully Coupled Propulsion-RANS ModelAirframe-propulsion integration concepts that use boundary layer ingestion have the potential to reduce aircraft fuel burn. One concept that has been recently explored is NASA's Starc-ABL aircraft configuration, which offers the potential for 12% mission fuel burn reduction by using a…16 pp20170001424
- Architecture, Voltage, and Components for a Turboelectric Distributed Propulsion Electric Grid (AVC-TeDP)The purpose of this effort was to advance the selection, characterization, and modeling of a propulsion electric grid for a Turboelectric Distributed Propulsion (TeDP) system for transport aircraft. The TeDP aircraft would constitute a miniature electric grid with 50 MW or more of total power, two…122 pp20150014583
- Archive data base and handling system for the Orbiter flying qualities experiment programThe OFQ archives data base and handling system assembled as part of the Orbiter Flying Qualities (OFQ) research of the Orbiter Experiments Program (EOX) are described. The purpose of the OFQ archives is to preserve and document shuttle flight data relevant to vehicle dynamics, flight control, and…83 pp19870004918
- Armstrong Flight Research Center Flight Test Capabilities and Opportunities for the Applications of Wireless Data Acquisition SystemsThe presentation will overview NASA Armstrong Flight Research Centers flight test capabilities, which can provide various means for flight testing of passive and active wireless sensor systems, also, it will address the needs of the wireless data acquisition solutions for the centers flight…17 pp20150008345
- Artificial Intelligence Based Control Power Optimization on Tailless AircraftTraditional methods of control allocation optimization have shown difficulties in exploiting the full potential of controlling large arrays of control devices on innovative air vehicles. Artificial neutral networks are inspired by biological nervous systems and neurocomputing has successfully been…15 ppNASA/TM-2014-218671
- Aspects of investigating STOL noise using large scale wind tunnel modelsThe applicability of the NASA Ames 40- by 80-ft wind tunnel for acoustic research on STOL concepts has been investigated. The acoustic characteristics of the wind tunnel test section has been studied with calibrated acoustic sources. Acoustic characteristics of several large-scale STOL models have…35 ppNASA-TM-X-62164
- ASRS for Unmanned Aviation SystemsThis presentation provides an overview of NASA's Aviation Safety Reporting System (ASRS) for Unmanned Aviation Systems / drones29 pp
- Assessing Fan Flutter Stability in Presence of Inlet Distortion Using One-Way and Two-Way Coupled MethodsConcerns regarding noise, propulsive efficiency, and fuel burn are inspiring aircraft designs wherein the propulsive turbomachines are partially (or fully) embedded within the airframe; such designs present serious concerns with regard to aerodynamic and aeromechanic performance of the compression…24 pp20150000732
- Assessing Fan Flutter Stability in the Presence of Inlet Distortion Using One-way and Two-way Coupled MethodsConcerns regarding noise, propulsive efficiency, and fuel burn are inspiring aircraft designs wherein the propulsive turbomachines are partially (or fully) embedded within the airframe; such designs present serious concerns with regard to aerodynamic and aeromechanic performance of the compression…13 pp20140016835
- Assessment of a Conceptual Flap System Intended for Enhanced General Aviation SafetyA novel multielement trailing-edge flap system for light general aviation airplanes was conceived for enhanced safety during normal and emergency landings. The system is designed to significantly reduce stall speed, and thus approach speed, with the goal of reducing maneuveringflight accidents and…244 ppNASA-TM-2017-219639
- Assessment of Off-Design Low-Boom Characteristics of a Low-Boom Supersonic TransportMost design methods for a low-boom supersonic aircraft were developed for achieving an undertrack low-boom goal at the start of cruise. Attempts were made to design a supersonic aircraft achieving a low-boom goal for multiple azimuthal angles at the start of cruise. One unanswered question is how…16 pp
- Assessment of Off-Design Low-Boom Characteristics of a Low-Boom Supersonic TransportMost conceptual design methods for low-boom supersonic aircraft are developed for achieving an undertrack low-boom goal at the start of cruise. Although attempts have been made to design a supersonic aircraft achieving a low-boom goal for multiple azimuthal angles at the start of cruise, one…11 pp
- Assessment of Some IASMS-relevant Data Sources for Aviation SafetyAn In-time Aviation Safety Management System (IASMS) [1,2] is a set of services, functions, and capabilities (SFCs) necessary for monitoring known hazards and emergent risks, assessing safety data for anomalies, precursors, and trends, mitigating hazards that reach safety thresholds, and assuring…13 pp
- Assessment Study of the State of the Art in Adaptive Control and its Applications to Aircraft ControlMany papers relevant to reconfigurable flight control have appeared over the past fifteen years. In general these have consisted of theoretical issues, simulation experiments, and in some cases, actual flight tests. Results indicate that reconfiguration of flight controls is certainly feasible for…23 pp
- ATD Occupant Responses from Three Full-Scale General Aviation Crash TestsDuring the summer of 2015, three Cessna 172 General Aviation (GA) aircraft were crash tested at the Landing and Impact Research (LandIR) Facility at NASA Langley Research Center (LaRC). Three different crash scenarios were represented. The first test simulated a flare-to-stall emergency or hard…43 pp20160005895
- Atmospheric Measurements for Flight Test at NASAs Neil A. Armstrong Flight Research CenterInformation enclosed is to be shared with students of Atmospheric Sciences, Engineering and High School STEM programs. Information will show the relationship between atmospheric Sciences and aeronautical flight testing.83 pp20160012047
- ATOPS B-737 inner-loop control system linear model construction and verificationNonlinear models and block diagrams of an inner-loop control system for the ATOPS B-737 Research Aircraft are presented. Continuous time linear model representations of the nonlinear inner-loop control systems are derived. Closed-loop aircraft simulations comparing nonlinear and linear dynamic…69 ppNASA-CR-166055
- Audio-Visual Situational Awareness for General Aviation PilotsWeather is one of the major causes of general aviation accidents. Researchers are addressing this problem from various perspectives including improving meteorological forecasting techniques, collecting additional weather data automatically via on-board sensors and "flight" modems, and improving…11 pp
- Automated optimum design of wing structures. Deterministic and probabilistic approachesThe automated optimum design of airplane wing structures subjected to multiple behavior constraints is described. The structural mass of the wing is considered the objective function. The maximum stress, wing tip deflection, root angle of attack, and flutter velocity during the pull up maneuver…52 pp19820021441
- Automated wing structural designResearch on the optimization of wing structures under multiple constraint such as strength, displacement, buckling, flutter, and divergence limits is reported. Advances were made in improving mathematical programming techniques as well as in improving the efficiency of constraint calculation. The…13 pp19760015100
- Automatic control design procedures for restructurable aircraft controlA simple, reliable automatic redesign procedure for restructurable control is discussed. This procedure is based on Linear Quadratic (LQ) design methodologies. It employs a robust control system design for the unfailed aircraft to minimize the effects of failed surfaces and to extend the time…72 ppNASA-CR-172489
- Avco Lycoming quiet clean general aviation turbofan engineA fan module was developed using an existing turboshaft engine. The fan was designed using the latest in large engine noise control technology. A mixer was added to reduce the already low exhaust gas velocity. A nacelle incorporating sound treatment was provided for the test engine. A noise…34 pp19800013846
- Aviation Safety Reporting System (ASRS)This overview of the NASA Aviation Safety Reporting System (ASRS) will describe the genesis of the program, report processing procedures, and safety products that are produced from the ASRS data.18 pp
- Axisymmetric Calculations of a Low-Boom Inlet in a Supersonic Wind TunnelThis paper describes axisymmetric CFD predictions made of a supersonic low-boom inlet with a facility diffuser, cold pipe, and mass flow plug within wind tunnel walls, and compares the CFD calculations with the experimental data. The inlet was designed for use on a small supersonic aircraft that…19 ppNASA/TM-2011-217224
- B-52 stability augmentation system reliabilityThe B-52 SAS (Stability Augmentation System) was developed and retrofitted to nearly 300 aircraft. It actively controls B-52 structural bending, provides improved yaw and pitch damping through sensors and electronic control channels, and puts complete reliance on hydraulic control power for rudder…18 pp
- Background Oriented Schlieren (BOS) of a Supersonic Aircraft in FlightThis article describes the development and use of Background Oriented Schlieren on a full-scale supersonic jet in flight. A series of flight tests was performed in October, 2014 and February 2015 using the flora of the desert floor in the Supersonic Flight Corridor on the Edwards Air Force Base as…22 ppARC-E-DAA-TN32991
- Background Oriented Schlieren (BOS) of a Supersonic Aircraft in FlightThis presentation describes the development and use of Background Oriented Schlieren (BOS) on a full-scale supersonic jet in flight. A series of flight tests was performed in October 2014 and February 2015 using the flora of the desert floor in the Supersonic Flight Corridor on the Edwards Air…28 ppARC-E-DAA-TN32990
- Background Oriented Schlieren (BOS) of a Supersonic Aircraft In FlightThis article describes the development and use of Background Oriented Schlieren on a full-scale supersonic jet in flight. A series of flight tests was performed in October, 2014 and February 2015 using the flora of the desert floor in the Supersonic Flight Corridor on the Edwards Air Force Base as…11 ppARC-E-DAA-TN32179
- Background Pressure Profiles for Sonic Boom Vehicle Testing in the NASA Glenn 8- by 6-Foot Supersonic Wind TunnelIn an effort to identify test facilities that offer sonic boom measurement capabilities, an exploratory test program was initiated using wind tunnels at NASA research centers. The subject of this report is the sonic boom pressure rail data collected in the Glenn Research Center 8- by 6-Foot…20 ppNASA/TM-2013-217903
- Baseline automotive gas turbine engine development programTests results on a baseline engine are presented to document the automotive gas turbine state-of-the-art at the start of the program. The performance characteristics of the engine and of a vehicle powered by this engine are defined. Component improvement concepts in the baseline engine were…180 ppNASA-CR-159670
- Basic avionics module design for general aviation aircraftThe design of an advanced digital avionics system (basic avionics module) for general aviation aircraft operated with a single pilot under IFR conditions is described. The microprocessor based system provided all avionic functions, including flight management, navigation, and lateral flight…155 pp19790003910
- Best Practices for Training the Structures Flight Test EngineerThe Structures Flight from 412th Test Wing and the Aerostructures Branch at NASA Armstrong Flight Research Center at Edwards Air Force Base have developed a set of best practices for training a structures flight test engineer. These practices represent the hard-won lessons learned and best…10 ppAFRC-E-DAA-TN56429
- Bibliography of NASA published reports on general aviation, 1975 to 1981This bibliography lists 478 documents which relate to all heavier-than-air fixed wing aircraft exclusive of military types and those used for commercial air transport. An exception is the inclusion of commuter transport aircraft types within the general aviation category. NASA publications included…284 pp19820011258
- Bimodal SLD Ice Accretion on a NACA 0012 Airfoil ModelThis presentation describes the results of ice accretion measurements on a NACA 0012 airfoil model, from the NASA Icing Research Tunnel, using an icing cloud composed of a bimodal distribution of Supercooled Large Droplets. The data consists of photographs, laser scans of the ice surface, and…24 ppGRC-E-DAA-TN43197
- Bimodal SLD Ice Accretion on a NACA 0012 Airfoil ModelAn initial ice shape database has been created to document ice accretions on a 21-inch chord NACA 0012 airfoil model resulting from an exposure to a Supercooled Large Droplet (SLD) icing cloud with a bimodal droplet distribution. The ice shapes created were documented with photographs, laser…12 ppGRC-E-DAA-TN42614
- Blade for turbine engineA blade for a turbine engine having a centerline. The blade comprises: a root section extending at an angle relative to the centerline; and an airfoil section extending from the root section. The root section is directly adjacent said airfoil section. In other words, the blade is neckless. The…16 pp20080005177
- Boeing Smart Rotor Full-scale Wind Tunnel Test Data ReportA full-scale helicopter smart material actuated rotor technology (SMART) rotor test was conducted in the USAF National Full-Scale Aerodynamics Complex 40- by 80-Foot Wind Tunnel at NASA Ames. The SMART rotor system is a five-bladed MD 902 bearingless rotor with active trailing-edge flaps. The flaps…424 ppNASA/TM-2016-216048
- Boundary Layer Development on a Turbine Blade in a Linear CascadeSeveral different boundary-layer development patterns for flow over the suction surface of a turbine airfoil in a linear cascade were studied and documented using a sliding surface hot-film sensor. The state of the boundary layer, whether laminar, transitional or turbulent, was determined at…26 pp20070038974
- Boundary-Layer-Transition Measurements in Full-Scale FlightChemical sublimation has been employed for boundary-layer-flow visualization on the wings of a supersonic fighter airplane in level flight at speeds near a Mach number of 2.0. The tests have shown that laminar flow can be obtained over extensive areas of the wing with practical wing-surface…11 pp19630008170
- Bounded Linear Stability Margin Analysis of Nonlinear Hybrid Adaptive ControlThis paper presents a bounded linear stability analysis for a hybrid adaptive control that blends both direct and indirect adaptive control. Stability and convergence of nonlinear adaptive control are analyzed using an approximate linear equivalent system. A stability margin analysis shows that a…6 ppARC-E-DAA-TN119
- Budget of Turbulent Kinetic Energy in a Shock Wave Boundary-Layer InteractionImplicit large-eddy simulation (ILES) of a shock wave/boundary-layer interaction (SBLI) was performed. Quantities present in the exact equation of the turbulent kinetic energy transport were accumulated and used to calculate terms like production, dissipation, molecular diffusion, and turbulent…20 pp20170000245
- C-5A/orbiter wind tunnel testing and analysis: Piggyback ferryWind tunnel testing and analytical studies of the feasibility of ferrying the NASA Shuttle Orbiter on the C-5A in a piggyback mode have been accomplished. Testing was conducted in the 8x12 foot low speed wind tunnel using an existing 0.0399 scale C-5A model in conjunction with a NASA 0.0405 scale…243 ppNASA-CR-134184
- Cabin Safety Issues Related to Pre-Departure and Inflight IssuesThe Aviation Safety Reporting System (ASRS) in a partnership between the National Aeronautics and Space Administration (NASA), the Federal Aviation Administration (FAA), participating carriers, and labor organizations. It is designed to improve the National Airspace System by collecting and…23 ppARC-E-DAA-TN13827
- Calculated and flight measured handling- qualities factors of three subsonic jet transportsCalculated and flight measured handling quality factors of three subsonic jet transports32 pp19690001164
- Calculated and Measured Pressure Distributions over the Midspan Section of the NACA 4412 AirfoilPressures were simultaneously measured in the variable-density tunnel at 54 orifices distributed over the midspan section of 5 by 30 inch rectangular model of the NACA 4412 airfoil at 17 angles of attack ranging from -20 degrees to 30 degrees at a Reynolds number of approximately 3,000,000.…20 ppNACA-TR-563
- Calculated Dynamic Characteristics of a Soft-Inplane Hingeless Rotor HelicopterCalculated dynamic characteristics of a representative soft-inplane hingeless rotor helicopter are presented. The flight dynamics as a function of speed and gross weight are given. The requirements for accurate analytical modelling of this helicopter are established. The influence of the horizontal…29 ppNASA-TM-73262
- Calculated Hovering Helicopter Flight Dynamics with a Circulation Controlled RotorThe influence of the rotor blowing coefficient on the calculated roots of the longitudinal and lateral motion was examined for a range of values of the rotor lift and the blade flap frequency. The control characteristics of a helicopter with a circulation controlled rotor are discussed. The…40 ppNASA-TM-78443
- Calculation of the bending stresses in helicopter rotor bladesA comparatively rapid method is presented for determining theoretically the bending stresses of helicopter rotor blades in forward flight. The method is based on the analysis of the properties of a vibrating beam, and its uniqueness lies in the simple solution of the differential equation which…33 ppNACA-TM-1312
- Calculation of the chordwise load distribution over airfoil sections with plain, split, or serially hinged trailing-edge flapsA method is presented for the rapid calculation of the incremental chordwise normal-force distribution over an airfoil section due to the deflection of a plain flap or tab, a split flap, or a serially hinged flap. This report is intended as a supplement to NACA Report no. 631, wherein a method is…24 ppNACA-TR-634
- Calculations of the Performance of a Compression-Ignition Engine-Compressor Turbine Combination I : Performance of a Highly Supercharged Compression-Ignition EngineSmall high-speed single-cylinder compression-ignition engines were tested to determine their performance characteristics under high supercharging. Calculations were made on the energy available in the exhaust gas of the compression-ignition engines. The maximum power at any given maximum cylinder…28 ppNACA-ARR-E5K06
- CAP-TSD analysis of the F-15 aircraftThe F-15 fighter aircraft was modeled using Computational Aeroelasticity Program - Transonic Small Disturbance (CAP-TSD). The complete aircraft was modeled including the wing, stabilator, flow through inlets, and fuselage body. CAP-TSD was used to make static pressure runs for Mach numbers of 0.8,…20 pp19890009868
- Capabilities of the Unitary Plan Wind TunnelAn overview of the capabilities of the NASA Ames Unitary Plan Wind Tunnel25 ppARC-E-DAA-TN38585
- CASCADE INVESTIGATION OF COOLING CHARACTERISTICS OF A CASTFINNED AIR-COOLED TURBINE BLADE FOR USE IN A TURBOPROP ENGINECascade investigation of cooling characteristics of air-cooled turbine blade for use in turboprop engine35 ppNACA-RM-E57D19
- CASCADE INVESTIGATION OF COOLING CHARACTERISTICS OF A CORRUGATEDINSERT AIR-COOLED TURBINE BLADE FOR USE IN A TURBOPROP ENGINEHeat transfer of air-cooled turbine blade for turboprop engine15 ppNASA-TM-X-85
- Certification Strategies using Run-Time Safety Assurance for Part 23 Autopilot SystemsPart 23 aircraft operation, and in particular general aviation, is relatively unsafe when compared to other common forms of vehicle travel. Currently, there exists technologies that could increase safety statistics for these aircraft; however, the high burden and cost of performing the requisite…10 ppAFRC-E-DAA-TN44007
- CF6 jet engine diagnostics program. High pressure turbine roundness/clearance investigationThe effects of high pressure turbine clearance changes on engine and module performance was evaluated in addition to the measurement of CF6-50C high pressure turbine Stage 1 tip clearance and stator out-of-roundness during steady-state and transient operation. The results indicated a good…123 pp19830004830
- CF6 jet engine performance deterioration resultsThe use of the performance baseline from the flight planning manual as a reference to measure changes in cruise fuel flow rates was discussed. For the CF6-6D engine, the introduction of design changes for performance and durability reasons was seen to introduce an average increment relative to this…20 pp
- CF6 Jet Engine Performance Improvement Program: High Pressure Turbine Aerodynamic Performance ImprovementThe improved single shank high pressure turbine design was evaluated in component tests consisting of performance, heat transfer and mechanical tests, and in core engine tests. The instrumented core engine test verified the thermal, mechanical, and aeromechanical characteristics of the improved…155 pp19800017803
- CF6 jet engine performance improvement program. Short core exhaust nozzle performance improvement conceptThe short core exhaust nozzle was evaluated in CF6-50 engine ground tests including performance, acoustic, and endurance tests. The test results verified the performance predictions from scale model tests. The short core exhaust nozzle provides an internal cruise sfc reduction of 0.9 percent…114 ppNASA-CR-159564
- CF6 jet engine performance improvement: New fanAs part of the NASA sponsored engine component improvement program, and fan package was developed to reduce fuel consumption in current CF6 turbofan aircraft engine. The new fan package consist of an improved fan blade, reduced fan tip clearance due to a fan case stiffener, and a smooth fan casing…202 ppNASA-CR-159699
- CF6-6D engine short-term performance deteriorationStudies conducted as part of the NASA-Lewis CF6 jet engine diagnostics program are summarized. An 82-engine sample of DC-10-10 aircraft engine checkout data that were gathered to define the extent and magnitude of CF6-6D short term performance deterioration were analyzed. These data are…153 ppNASA-CR-159830
- CFD Study of NACA 0018 Airfoil with Flow ControlThe abilities of two different Reynolds-Averaged Navier-Stokes codes to predict the effects of an active flow control device are evaluated. The flow control device consists of a blowing slot located on the upper surface of an NACA 0018 airfoil, near the leading edge. A second blowing slot present…39 ppNASA/TM-2017-219602
- Changing the Landscape of Civil AviationNASA is undertaking several bold new initiatives to develop revolutionary technologies for civil aviation. These technologies span the civil aviation fleet from general aviation to large subsonic and supersonic aircraft and promise to bring a new era of new aircraft, lower operation costs, faster…14 pp19970035085
- Characteristics of a Lunar Landing Configuration Having Various Multiple-Leg Landing-Gear ArrangementsAn experimental investigation has been made of some lunar-landing characteristics of a 1/6-scale dynamic model of a landing module having multiple-leg landing-gear systems. Symmetric four-point and five-point systems were investigated. The landing-gear legs were inverted tripod arrangements having…46 ppNASA-TN-D-2027
- Characteristics of Boundary Layer Transition in a Multi-Stage Low-Pressure TurbineAn experimental investigation of boundary layer transition in a multi-stage turbine has been completed using surface-mounted hot-film sensors. Tests were carried out using the two-stage Low Speed Research Turbine of the Aerodynamics Research Laboratory of GE Aircraft Engines. Blading in this…20070038956
- Characteristics of NACA 4400R Series Rectangular and Tapered Airfoils, Including the Effect of Split FlapsNo abstract available16 ppNACA-WR-L-493
- Characterization of Ice Roughness Variations in Scaled Glaze Icing ConditionsBecause of the significant influence of surface tension in governing the stability and breakdown of the liquid film in flooded stagnation regions of airfoils exposed to glaze icing conditions, the Weber number is expected to be a significant parameter governing the formation and evolution of ice…14 pp20170000244
- Charts Showing Relations Among Primary Aerodynamic Variables for Helicopter-performance EstimationIn order to facilitate solutions of the general problem of helicopter selection, the aerodynamic performance of rotors is presented in the form of charts showing relations between primary design and performance variables. By the use of conventional helicopter theory, certain variables are plotted…54 ppNACA-TN-1192
- Circulation control propellers for general aviation, including a BASIC computer programThe feasibility of replacing variable pitch propeller mechanisms with circulation control (Coanada effect) propellers on general aviation airplanes was examined. The study used a specially developed computer program written in BASIC which could compare the aerodynamic performance of circulation…92 pp19850021647
- Civil applications of high-speed rotorcraft and powered-lift aircraft configurationsAdvanced subsonic vertical and short takeoff and landing (V/STOL) aircraft configurations offer new transportation options for civil applications. Described is a range of vehicles from low-disk to high-disk loading aircraft, including high-speed rotorcraft, V/STOL aircraft, and short takeoff and…27 pp19880002261
- CMC Technology Advancements for Gas Turbine Engine ApplicationsCMC research at NASA Glenn is focused on aircraft propulsion applications. The objective is to enable reduced engine emissions and fuel consumption for more environmentally friendly aircraft. Engine system studies show that incorporation of ceramic composites into turbine engines will enable…19 pp20140000458
- Cmparison of flight-measured helicopter rotor-blade chordwise pressure distributions with static two-dimensional airfoil characteristicsHelicopter rotor blade pressure distributions compared with static two-dimensional airfoil characteristics for extreme flight conditions57 ppNASA-TN-D-3936
- Cockpit Technology for Prevention of General Aviation Runway IncursionsGeneral aviation accounted for 74 percent of runway incursions but only 57 percent of the operations during the four-year period from fiscal year (FY) 2001 through FY2004. Elements of the NASA Runway Incursion Prevention System were adapted and tested for general aviation aircraft. Sixteen General…6 pp
- Cold-air investigation of a turbine for high-temperature-engine applicationOverall performance of stator component of cold air turbine determined for application to high temperature engine design28 ppNASA-TN-D-3751
- Cold-air performance evaluation of a scale- model fuel pump turbine for the M-1 hydrogen-oxygen rocket engineCold air performance of scale model fuel pump turbine for M-1 hydrogen-oxygen rocket engine36 ppNASA-TN-D-3819
- Cold-air performance evaluation of scale model oxidizer pump-drive turbine for the M-1 hydrogen-oxygen rocket engine. I - Inlet feedpipe-manifold assemblyCold air performance of scale model oxidizer pump drive turbine feedpipe-manifold-nozzle assembly for M-1 rocket engine30 ppNASA-TN-D-3294
- Cold-air performance of compressor-drive turbine of Department of Energy upgraded automobile gas turbine engine. 2: Stage performanceThe aerodynamic performance of the compressor-drive turbine of the DOE upgraded gas turbine engine was determined in low temperature air. The as-received cast rotor blading had a significantly thicker profile than design and a fairly rough surface finish. Because of these blading imperfections a…24 pp19830002793
- Cold-air performance of compressor-drive turbine of department of energy upgraded automobile gas turbine engine. 3: Performance of redesigned turbineThe aerodynamic performance of a redesigned compressor drive turbine of the gas turbine engine is determined in air at nominal inlet conditions of 325 K and 0.8 bar absolute. The turbine is designed with a lower flow factor, higher rotor reaction and a redesigned inlet volute compared to the first…46 pp19840017576
- Cold-air performance of the compressor-drive turbine of the Department of Energy baseline automobile gas-turbine engineThe aerodynamic performance of the compressor-drive turbine of the DOE baseline gas-turbine engine was determined over a range of pressure ratios and speeds. In addition, static pressures were measured in the diffusing transition duct located immediately downstream of the turbine. Results are…25 pp19780018155
- Collaborative Experiments and Computations in Aircraft IcingThe formation of ice over lifting surfaces can affect aerodynamic performance. The ability to predict ice accumulation and the resulting degradation in vehicle performance is essential to determine the limitations of aircraft in icing encounters. The consequences of underestimating performance…11 ppGRC-E-DAA-TN56891
- COMBUSTION PERFORMANCE OF TWO EXPERIMENTAL TURBOJET ANNULAR COMBUSTORS AT CONDITIONS SIMULATING HIGH-ALTITUDE SUPERSONIC FLIGHTPerformance of experimental annular turbojet combustors at simulated high altitude supersonic flight conditions28 ppNACA-RM-E54A15
- Commercial aviation icing research requirementsA short range and long range icing research program was proposed. A survey was made to various industry and goverment agencies to obtain their views of needs for commercial aviation ice protection. Through these responsed, other additional data, and Douglas Aircraft icing expertise; an assessment…67 ppNASA-CR-165336
- Community reaction to aircraft noise around smaller city airportsThe results are presented of a study of community reaction to jet aircraft noise in the vicinity of airports in Chattanooga, Tennessee, and Reno, Nevada. These cities were surveyed in order to obtain data for comparison with that obtained in larger cities during a previous study. (The cities…194 pp19720022361
- Community reactions to aircraft noise - Noise measurementsAcoustical and social data on community reactions to aircraft noise11 pp
- Community reactions to aircraft noise - Public reactionsPopulation survey on reactions to aircraft noise in airport vicinity12 pp
- Comparative Drag Measurements at Transonic Speeds of Rectangular Sweptback NACA 65-009 Airfoils Mounted on a Freely Falling BodyDirectly comparable drag measurements have been made of an airfoil with a conventional rectangular plan form and an airfoil with a sweptback plan form mounted on freely falling bodies. Both airfoils had NACA 65-009 sections and were identical in span, frontal area, and chord perpendicular to the…12 ppNACA-TR-988
- Comparing 3D and 2D CFD for Mars Helicopter Ingenuity Rotor Performance PredictionSingle and coaxial rotor performance simulations for the Mars Helicopter Ingenuity rotor are performed for representative Mars atmospheric conditions. Analyses are presented using both a high-fidelity 3D CFD model of the rotor and 2D CFD models of the airfoil sections for comprehensive analyses…15 pp
- Comparison of acoustic data from a 102 mm conic nozzle as measured in the RAE 24-foot wind tunnel and the NASA Ames 40- by 80-foot wind tunnelA cooperative program between the Royal Aircraft Establishment (RAE), England, and the NASA Ames Research Center was initiated to compare acoustic measurements made in the RAE 24-foot wind tunnel and in the Ames 40- by 80-foot wind tunnel. The acoustic measurements were made in both facilities…27 ppNASA-TM-81343
- Comparison of Aircraft Conceptual Design Weight Estimation Methods to the Flight Optimization SystemWeight estimation is critical in the aircraft conceptual design process. The Flight Optimization System (FLOPS) is an aircraft conceptual design tool that has been the primary aircraft synthesis software used by the Systems Analysis and Concepts Directorate at NASA Langley Research Center. FLOPS…19 ppAIAA-2018-2032
- Comparison of Aircraft Icing Growth Assessment SoftwareA research project is underway to produce computer software that can accurately predict ice growth under any meteorological conditions for any aircraft surface. An extensive comparison of the results in a quantifiable manner against the database of ice shapes that have been generated in the NASA…2 pp20110002989
- Comparison of Boeing 777 Landing Gear Noise Simulations with Flight Test DataAcoustic phased microphone array measurements of aircraft flyover noise acquired during the 2005 Quiet Technology Demonstrator II test were used to assess the accuracy of high-fidelity, full-scale simulations of landing gear noise produced by a large civilian aircraft. The simulations, conducted…12 pp
- Comparison of control-fixed stability derivatives for two supersonic fighter airplanes as determined from flight and wind-tunnel testsComparison of control-fixed stability derivatives for two supersonic fighters as determined from flight and wind tunnel tests34 ppNASA-MEMO-2-3-59L
- Comparison of Drop and Wind-Tunnel Experiments on Bomb Drag at High Subsonic SpeedsThe drag coefficients of bombs at high velocities velocity of fall was 97 percent of the speed of sound) (the highest are determined by drop tests and compared with measurements taken in the DVL high-speed closed wind tunnel and the open jet at AVA - Gottingen.14 pp20050019654
- Comparison of Flight Measured Helicopter Rotor Blade Chordwise Pressure Distributions and Two-Dimensional Airfoil CharacteristicsHelicopter rotor blade chordwise pressure distribution and two-dimensional airfoil characteristics21 pp
- Comparison of Heat Transfer from Airfoil in Natural and Simulated Icing ConditionsAn investigation of the heat transfer from an airfoil in clear air and in simulated icing conditions was conducted in the NACA Lewis 6- by 9-foot icing-research tunnel in order to determine the validity of heat-transfer data as obtained in the tunnel. This investiation was made on the same model…52 ppNACA-TN-2480
- Comparison of In-Situ, Model and Ground Based In-Flight Icing SeverityCurrently there are two systems that are being developed for the detection of in-flight icing: NASA Icing Remote Sensing System (NIRSS) and current Icing Product (CIP). In-flight icing (IFI) is a significant hazard for the aviation industry. IFI occurs when supercooled liquid water (SLW) comes in…1 pp20150010148
- Comparison of In-Situ, Model and Ground Based In-Flight Icing SeverityAs an aircraft flies through supercooled liquid water, the liquid freezes instantaneously to the airframe thus altering its lift, drag, and weight characteristics. In-flight icing is a contributing factor to many aviation accidents, and the reliable detection of this hazard is a fundamental concern…12 pp20120000908
- Comparison of Mars Aircraft Propulsion SystemsThe propulsion system is a critical aspect of the performance and feasibility of a Mars aircraft. Propulsion system mass and performance greatly influence the aircraft s design and mission capabilities. Various propulsion systems were analyzed to estimate the system mass necessary for producing 35N…87 pp20030056588
- Comparison of Methods for Efficient Static Wind Tunnel Testing Using Multiple Control SurfacesThe Integrated Adaptive Wing Technology Maturation (IAWTM) half-span wind tunnel test article was tested in the Transonic Dynamics Tunnel (TDT) at NASA's Langley Research Center in Hampton, VA. The test article has a wing aspect ratio of 13.5, wing half span length of 12.75 ft, and is configured…25 pp
- Comparison of model and flight test data for an augmented jet flap STOL research aircraftAerodynamic design data for the Augmented Jet Flap STOL Research Aircraft or commonly known as the Augmentor-Wing Jet-STOL Research Aircraft was based on results of tests carried out on a large scale research model in the NASA Ames 40- by 80-Foot Wind Tunnel. Since the model differs in some…45 ppNASA-TM-X-62491
- Comparison of Pitching Moments Produced by Plain Flaps and by Spoilers and Some Aerodynamic Characteristics of an NACA 23012 Airfoil with Various Types of AileronSectional characteristics of airfoil having retractable slotted flap with plain, slot-lip, or retractable ailerons are presented for a large range of aileron deflections. The analysis indicated that pitching moments produced by spoilers were less positive than those produced by plain flaps of equal…18 ppNACA-ACR-L5C24a
- Comparison of RTA Vibratory Loading in the 40- by 80-Foot Wind Tunnel and 80- by 120-Foot Wind Tunnel at the National Full-Scale Aerodynamics ComplexThis paper presents data taken in the 80- by 120-Foot Wind Tunnel in 1992 to data taken in the 40- by 80-Foot Wind Tunnel in 2016 at the NFAC. In both sets of data, the RTA was equipped with an identical set of S-76 helicopter blades. These data sets were compared to determine the repeatability of…21 ppARC-E-DAA-TN34899
- Comparison of Satellite and Aircraft Measurements of Cloud Microphysical Properties in Icing Conditions During ATREC/AIRS-IISatellites are ideal for continuous monitoring of aircraft icing conditions in many situations over extensive areas. The satellite imager data are used to diagnose a number of cloud properties that can be used to develop icing intensity indices. Developing and validating these indices requires…4 ppPaper 6.10
- Comparison of stability and control parameters for a light, single-engine, high-winged aircraft using different flight test and parameter estimation techniquesThe longitudinal and lateral stability and control parameters for a high wing, general aviation, airplane are examined. Estimations using flight data obtained at various flight conditions within the normal range of the aircraft are presented. The estimations techniques, an output error technique…58 ppNASA-TM-80163
- Comparison of the CHARM Predictions of the Multirotor Test Bed with Wind Tunnel Experimental ResultsUrban air mobility as a fast transportation solution has captured the attention of private companies and government aviation departments in the 21st century. New designs of aerial vehicles are being developed to meet industry needs but often neglect the aerodynamic characteristics and the effects…21 pp
- Comparison of wind tunnel and flight test afterbody and nozzle pressures for a twin-jet fighter aircraft at transonic speedsAfterbody and nozzle pressures measured on a 1/12-scale model and in flight on a twin-jet fighter aircraft were compared as Mach number varied from 0.6 to 1.2, Reynolds number from 17.5 million to 302.5 million, and angle of attack from 1 to 7 deg. At Mach 0.6 and 0.8, nozzle pressure coefficient…124 ppNASA-TP-2588
- Comparison of wind tunnel and flyover noise measurements of the YOV-10A STOL aircraftThe YOV-10A Research Aircraft was flown to obtain flyover noise data that could be compared to noise data measured in the 40- by 80- foot wind tunnel at NASA Ames Research Center. The flyover noise measurements were made during the early morning hours on runway 32L at Moffett Field, California. A…28 ppNASA-TM-X-62166
- Comparison of wind-tunnel and flight results on a four-propeller tilt-wing configurationOver the years aerodynamicists have learned to rely heavily on wind-tunnel-model results in predicting the aerodynamic characteristics of conventional aircraft configurations. With the development of V/STOL configurations which have high slipstream deflection angles. such as the four-propeller…
- Comparisons of four alternative powerplant types for future general aviation aircraftRecently completed NASA sponsored conceptual studies were culminated in the identification of promising new technologies for future spark ignition, diesel, rotary, and turbine engines. The results of a NASA in-house preliminary assessment study that compares these four powerplants types in several…52 pp19810001559
- Comparisons of Mixed-Phase Icing Cloud Simulations with Experiments Conducted at the NASA Propulsion Systems LaboratoryThis paper builds on previous work that compares numerical simulations of mixed-phase icing clouds with experimental data. The model couples the thermal interaction between ice particles and water droplets of the icing cloud with the flowing air of an icing wind tunnel for simulation of NASA Glenn…22 pp20170007927
- Compilation of Papers Summarizing Some Recent NASA Research on Manned Military AircraftThe nine papers included in this volume were presented by NASA research staff members at the National Meeting on the Future of Manned Military Aircraft sponsored by the Institute of the Aeronautical Sciences and held in San Diego, Calif., from August 1 to August 3, 1960. Because, together, they…156 pp19670023741
- Completion of Dragonfly PPF Testing in the NFAC 80x120-Foot Wind TunnelThe Dragonfly entry, descent, and landing team (JHU-APL, NASA Langley Research Center, NASA Ames Research Center, Sikorsky Aircraft) recently completed testing in the National Full-Scale Aerodynamics Complex (NFAC) 80x120-Foot Wind Tunnel. The facility is located at NASA Ames Research Center and is…15 ppLaRC-DFLY-0001
- Complexity and Pilot Workload Metrics for the Evaluation of Adaptive Flight Controls on a Full Scale Piloted AircraftFlight research has shown the effectiveness of adaptive flight controls for improving aircraft safety and performance in the presence of uncertainties. The National Aeronautics and Space Administration's (NASA)'s Integrated Resilient Aircraft Control (IRAC) project designed and conducted a series…21 pp20140005730
- Composite aircraft structure having lightning protectionA lightning protection system for advanced composite aircraft structures consisting of a sandwich structure including two layers of aluminum foil separated by a layer of dielectric material. The sandwich structure is applied to the surface of the composite aircraft structure desired to be protected…4 pp20080004217
- Compound cycle engine for helicopter applicationThe compound cycle engine (CCE) is a highly turbocharged, power-compounded, ultra-high-power-density, lightweight diesel engine. The turbomachinery is similar to a moderate-pressure-ratio, free-power-turbine gas turbine engine and the diesel core is high speed and a low compression ratio. This…196 ppNASA-CR-180824
- Compound cycle engine for helicopter applicationThe Compound Cycle Engine (CCE) is a highly turbocharged, power compounded, ultra-high power density, light-weight diesel engine. The turbomachinery is similar to a moderate pressure ratio, free power turbine engine and the diesel core is high speed and a low compression ratio. This engine is…13 ppNASA-CR-175110
- Compound cycle engine programThe Compound Cycle Engine (CCE) is a highly turbocharged, power compounded power plant which combines the lightweight pressure rise capability of a gas turbine with the high efficiency of a diesel. When optimized for a rotorcraft, the CCE will reduce fuel burned for a typical 2 hr (plus 30 min…23 ppNASA-TM-88879
- Compound Wing Vertical Takeoff and Landing Small Unmanned Aircraft SystemSystems, methods, and devices are provided that enable robust operations of a small unmanned aircraft system (sUAS) using a compound wing. The various embodiments may provide a sUAS with vertical takeoff and landing capability, long endurance, and the capability to operate in adverse environmental…14 pp20170007230
- Comprehensive rotorcraft analysis methodsThe development and application of comprehensive rotorcraft analysis methods in the field of rotorcraft technology are described. These large scale analyses and the resulting computer programs are intended to treat the complex aeromechanical phenomena that describe the behavior of rotorcraft. They…38 pp19880007247
- Compressible, unsteady lifting-surface theory for a helicopter rotor in forward flightA lifting-surface theory has been developed for a helicopter rotor in forward flight for compressible and incompressible flow. The method utilizes the concept of the linearized acceleration potential and makes use of the doublet lattice procedure. Calculations demonstrating the application of the…21 ppNASA-TP-2503
- Computation of helicopter rotor acoustics in forward flightThis paper presents a new method for computing acoustic signals from helicopter rotors in forward flight. The aerodynamic and acoustic solutions in the near field are computed with a finite-difference solver for the Euler equations. A nonrotating cylindrical Kirchhoff surface is then placed around…12 ppNASA-CR-196132
- Computation of viscous transonic flow about a lifting airfoilThe viscous transonic flow about a stationary body in free air was numerically investigated. The geometry chosen was a symmetric NACA 64A010 airfoil at a freestream Mach number of 0.8, a Reynolds number of 4 million based on chord, and angles of attack of 0 and 2 degrees. These conditions were such…93 ppNASA-CR-151999
- Computational Analysis of the External Aerodynamics of the Unpowered X-57 Mod-III AircraftInvestigations of the external aerodynamics of the unpowered X-57 Mod-III configuration using computational fluid dynamics are presented. Two different Reynolds-averaged Navier-Stokes flow solvers were used in the analysis: the STAR-CCM+ unstructured solver using polyhedral grid topology, and the…18 pp20190026506
- Computational Analysis of the External Aerodynamics of the Unpowered X-57 Mod-III AircraftInvestigations of the external aerodynamics of the unpowered X-57 using computational fluid dynamics are presented.27 pp20190026696
- Computational Assessment of the Benefits of Boundary Layer Ingestion for the D8 AircraftTo substantially reduce the fuel burn of future commercial transportation aircraft, the boundary layer ingestion idea is investigated. The idea is that an engine placed in the wake of the aircraft it is propelling is more efficient than a conventional engine placement under the wing or on pods…10 pp20140004910
- Computational design of low aspect ratio wing-winglet configurations for transonic wind-tunnel testsA computational design has been performed for three different low aspect ratio wing planforms fitted with nonplanar winglets; one of the three planforms has been selected to be constructed as a wind tunnel model for testing in the NASA LaRC 7 x 10 High Speed Wind Tunnel. A design point of M = 0.8,…64 pp19880015246
- Computational Icing Analysis on NASA’s SIDRM Geometry to Investigate Collection EfficiencyComputational icing analysis results were compared to experimental icing tunnel data including aerothermal (e.g. dry air) and supercooled water droplet rime-ice conditions from tests conducted in early 2022 at the NASA Icing Research Tunnel (IRT). The Simulated Intercompressor Duct Research Model…17 pp
- Computational Icing Risk Analysis of the D8 "Double Bubble" AircraftA computational icing risk analysis utilizing LEWICE3D was performed for the D8 Double Bubble aircraft. A variety of discrete drop sizes spanning the Appendix C and O regimes were simulated. For computational efficiency a 50-bin global discretization was produced and projected onto the…36 ppNASA/TM-2018-220006
- Computational Icing Risk Analysis of the D8 "Double Bubble" AircraftA computational icing risk analysis utilizing LEWICE3D was performed for the D8 Double Bubble aircraft. A variety of discrete drop sizes spanning the Appendix C and O regimes were simulated. For computational efficiency a 50-bin global discretization was produced and projected onto the…27 ppGRC-E-DAA-TN55986
- Computational Methods for Stability and Control (COMSAC): The Time Has ComePowerful computational fluid dynamics (CFD) tools have emerged that appear to offer significant benefits as an adjunct to the experimental methods used by the stability and control community to predict aerodynamic parameters. The decreasing costs for and increasing availability of computing hours…40 ppAIAA Paper 2005-6121
- Computational Results for the KTH-NASA Wind-Tunnel Model Used for Acquisition of Transonic Nonlinear Aeroelastic DataA status report is provided on the collaboration between the Royal Institute of Technology (KTH) in Sweden and the NASA Langley Research Center regarding the aeroelastic analyses of a full-span fighter configuration wind-tunnel model. This wind-tunnel model was tested in the Transonic Dynamics…19 pp20170001026
- Computational study of generic hypersonic vehicle flow fieldsThe geometric data of the generic hypersonic vehicle configuration included body definitions and preliminary grids for the forebody (nose cone excluded), midsection (propulsion system excluded), and afterbody sections. This data was to be augmented by the nose section geometry (blunt conical…68 pp19940029771
- Computational Support of 9x7 Wind Tunnel Test of Sonic Boom Models with PlumesNASA and its industry partners are performing studies of supersonic aircraft concepts with low sonic boom pressure signatures. The interaction of the nozzle jet flow with the aircrafts' aft components is typically where the greatest uncertainly in the pressure signature is observed with…44 ppARC-E-DAA-TN40151
- Computational thermo-fluid dynamics contributions to advanced gas turbine engine designThe design practices for the gas turbine are traced throughout history with particular emphasis on the calculational or analytical methods. Three principal components of the gas turbine engine will be considered: namely, the compressor, the combustor and the turbine.14 pp19850001762
- Computed and Experimental Flutter/LCO Onset for the Boeing Truss-Braced Wing Wind-Tunnel ModelThis paper presents high fidelity Navier-Stokes simulations of the Boeing Subsonic Ultra Green Aircraft Research truss-braced wing wind-tunnel model and compares the results to linear MSC. Nastran flutter analysis and preliminary data from a recent wind-tunnel test of that model at the NASA Langley…24 ppNF1676L-17719
- Computer and engine performance study of a generalized parameter fuel control for jet enginesComputer and engine performance study of jet engine generalized parameter fuel control40 ppNASA-TN-D-5871
- Computer program user's manual for advanced general aviation propeller studyA user's manual is presented for a computer program for predicting the performance (static, flight, and reverse), noise, weight and cost of propellers for advanced general aviation aircraft of the 1980 time period. Complete listings of this computer program with detailed instructions and samples of…78 pp19720017355
- Computer Simulation of Aircraft AerodynamicsThe role of Ames Research Center in conducting basic aerodynamics research through computer simulations is described. The computer facilities, including supercomputers and peripheral equipment that represent the state of the art, are described. The methodology of computational fluid dynamics is…11 pp19900002383
- Computer simulation of aircraft motions and propulsion system dynamics for the YF-12 aircraft at supersonic cruise conditionsA computer simulation of the YF-12 aircraft motions and propulsion system dynamics is presented. The propulsion system was represented in sufficient detail so that interactions between aircraft motions and the propulsion system dynamics could be investigated. Six degree-of-freedom aircraft motions…66 pp19730020258
- Computer technology forecast study for general aviationA multi-year, multi-faceted program is underway to investigate and develop potential improvements in airframes, engines, and avionics for general aviation aircraft. The objective of this study was to assemble information that will allow the government to assess the trends in computer and…347 pp19760023126
- COMSAC: Computational Methods for Stability and ControlThe unprecedented advances being made in computational fluid dynamic (CFD) technology have demonstrated the powerful capabilities of codes in applications to civil and military aircraft. Used in conjunction with wind-tunnel and flight investigations, many codes are now routinely used by designers…389 ppNASA/CP-2004-213028/PT2
- COMSAC: Computational Methods for Stability and ControlWork on stability and control included the following reports:Introductory Remarks; Introduction to Computational Methods for Stability and Control (COMSAC); Stability & Control Challenges for COMSAC: a NASA Langley Perspective; Emerging CFD Capabilities and Outlook A NASA Langley Perspective; The…385 ppNASA/CP-2004-213028/PT1
- Concepts for Multi-Speed Rotorcraft Drive System - Status of Design and Testing at NASA GRCIn several studies and on-going developments for advanced rotorcraft, the need for variable multi-speed capable rotors has been raised. Speed changes of up to 50 have been proposed for future rotorcraft to improve vehicle performance. A rotor speed change during operation not only requires a rotor…27 pp20150010212
- Concepts for Multi-Speed Rotorcraft Drive System - Status of Design and Testing at NASA GRCIn several studies and on-going developments for advanced rotorcraft, the need for variable/multi-speed capable rotors has been raised. Speed changes of up to 50 percent have been proposed for future rotorcraft to improve vehicle performance. A rotor speed change during operation not only requires…17 pp20150010716
- Conceptual Design of Environmentally Friendly Rotorcraft - A Comparison of NASA and ONERA ApproachesIn 2011, a task was initiated under the US-French Project Agreement on rotorcraft studies to collaborate on design methodologies for environmentally friendly rotorcraft. This paper summarizes the efforts of that collaboration. The French and US aerospace agencies, ONERA and NASA, have their own…21 pp20150011434
- Conference on Aircraft Operating ProblemsConference on aircraft operational problems of general, supersonic, V/STOL and STOL aircraft315 pp19650021499
- Conference on V/STOL and STOL aircraftThis compilation contains results of recent NASA research on problems associated with V/STOL and STOL aircraft. The first three sections include papers presented at the NASA Conference on V/STOL and STOL Aircraft held at the Ames Research Center, Moffett Field, California, on April 4 and 5, 1966.…NASA-SP-116
- Conference scope and noise conceptsGuidelines and objectives of aircraft noise reduction conference10 pp19690002213
- Configuration Aerodynamics: Past - Present - FutureThe Configuration Aerodynamics (CA) element of the High Speed Research (HSR) program is managed by a joint NASA and Industry team, referred to as the Technology Integration Development (ITD) team. This team is responsible for the development of a broad range of technologies for improved aerodynamic…26 pp20000044618
- Configuration development study of the OSU 1 hypersonic research vehicleIn an effort to insure the future development of hypersonic cruise aircraft, the possible vehicle configurations were examined to develop a single-stage-to-orbit hypersonic research vehicle (HRV). Based on the needs of hypersonic research and development, the mission goals and requirements are…155 pp19940020118
- Configuration management and automatic control of an augmentor wing aircraft with vectored thrustAn advanced structure for automatic flight control logic for powered-lift aircraft operating in terminal areas is under investigation at Ames Research Center. This structure is based on acceleration control; acceleration commands are constructed as the sum of acceleration on the reference…142 ppNASA-TP-1222
- Considerations in the determination of stability and control derivatives and dynamic characteristics from flight dataDetermining stability and control and dynamic characteristics from flight test data191 ppAGARD-549, PT. I
- Considerations regarding the evaluation and reduction of supersonic skin frictionExperimental and predicted data on turbulent boundary-layer skin friction of supersonic transport configuration21 pp19660027862
- Construction, wind tunnel testing and data analysis for a 1/5 scale ultra-light wing modelThis report documents the construction, wind tunnel testing, and data analysis of a 1/5 scale ultra-light wing section. Wind tunnel testing provided accurate and meaningful lift, drag, and pitching moment data. This data was processed and graphically presented as follows: C(sub L) vs. gamma; C(sub…46 pp19930020589
- Contingency power for a small turboshaft engine by using water injection into turbine cooling airBecause of one-engine-inoperative (OEI) requirements, together with hot-gas reingestion and hot-day, high-altitude take-off situations, power augmentation for multiengine rotorcraft has always been of critical interest. However, power augmentation by using overtemperature at the turbine inlet will…12 pp19920020418
- Continued study of NAVSTAR/GPS for general aviationA conceptual approach for examining the full potential of Global Positioning Systems (GPS) for the general aviation community is presented. Aspects of an experimental program to demonstrate these concepts are discussed. The report concludes with the observation that the true potential of GPS can…224 pp19800009756
- Continuous measurement of aircraft wing icingIce formation on the wings of aircraft is a problem that has plagued air travel since its inception. Several recent incidents have been attributed to ice formation on the lifting surfaces of wings. This paper describes a SBIR Phase 1 research effort on the use of small flat dielectric sensors in…6 pp
- Contributions of the Transonic Dynamics Tunnel to the Testing of Active Control of Aeroelastic ResponseBy the 1960s, researchers began to investigate the feasibility of using active controls technology (ACT) for increasing the capabilities of military and commercial aircraft. Since then many researchers, too numerous to mention, have investigated and demonstrated the usefulness of ACT for favorably…18 pp20000037722
- Control Architecture for a Concept Aircraft with a Series/Parallel Partial Hybrid Powertrain and Distributed Electric PropulsionTraditional aircraft propulsion control approaches are insufficient for electrified aircraft powertrains due to their increased complexity compared to current systems. New control approaches are required to manage the increased interdependency and complexity of these electrified powertrains.…26 ppAIAA 2023-1750
- Control Architecture for a Concept Aircraft with a Series/Parallel Partial Hybrid Powertrain and Distributed Electric PropulsionTraditional aircraft propulsion control approaches are insufficient for electrified aircraft powertrains due to their increased complexity compared to current systems. New control approaches are required to manage the increased interdependency and complexity of these electrified powertrains.…13 pp
- Control Architecture for a Concept Aircraft with a Series/Parallel Partial Hybrid Powertrain and Distributed Electric PropulsionTraditional aircraft propulsion control approaches are insufficient for electrified aircraft powertrains due to their increased complexity compared to current systems. New control approaches are required to manage the increased interdependency and complexity of these electrified powertrains.…16 ppAIAA-2023-1750
- Control Design for a Generic Commercial Aircraft EngineThis paper describes the control algorithms and control design process for a generic commercial aircraft engine simulation of a 40,000 lb thrust class, two spool, high bypass ratio turbofan engine. The aircraft engine is a complex nonlinear system designed to operate over an extreme range of…24 pp20100037768
- Control law system for X-Wing aircraftControl law system for the collective axis, as well as pitch and roll axes, of an X-Wing aircraft and for the pneumatic valving controlling circulation control blowing for the rotor. As to the collective axis, the system gives the pilot single-lever direct lift control and insures that maximum…31 ppPatent Application Number: US-PATENT-APPL-SN-256937
- Control of propulsion systems for supersonic cruise aircraftThe propulsion control requirements of supersonic aircraft are presented. Integration of inlet, engine, and airframe controls is discussed. The application of recent control theory developments to propulsion control design is described. Control component designs for achieving reliable, responsive…17 pp19770011072
- Control optimization, stabilization and computer algorithms for aircraft applicationsResearch related to reliable aircraft design is summarized. Topics discussed include systems reliability optimization, failure detection algorithms, analysis of nonlinear filters, design of compensators incorporating time delays, digital compensator design, estimation for systems with echoes,…26 ppNASA-CR-145862
- Control Reallocation Strategies for Damage Adaptation in Transport Class AircraftThis paper examines the feasibility, potential benefits and implementation issues associated with retrofitting a neural-adaptive flight control system (NFCS) to existing transport aircraft, including both cable/hydraulic and fly-by-wire configurations. NFCS uses a neural network based direct…7 pp
- Control Surface Interaction Effects of the Active Aeroelastic Wing Wind Tunnel ModelThis paper presents results from testing the Active Aeroelastic Wing wind tunnel model in NASA Langley s Transonic Dynamics Tunnel. The wind tunnel test provided an opportunity to study aeroelastic system behavior under combined control surface deflections, testing for control surface interaction…16 pp20060018311
- Control technology for future aircraft propulsion systemsThe need for a more sophisticated engine control system is discussed. The improvements in better thrust-to-weight ratios demand the manipulation of more control inputs. New technological solutions to the engine control problem are practiced. The digital electronic engine control (DEEC) system is a…17 pp19860015885
- Control Technology Needs for Electrified Aircraft Propulsion SystemsElectrified aircraft propulsion (EAP) systems hold potential for the reduction of aircraft fuel burn, emissions, and noise. Currently, NASA and other organizations are actively working to identify and mature technologies necessary to bring EAP designs to reality. This paper specifically focuses on…13 pp20190027038
- Control Technology Needs for Electrified Aircraft Propulsion SystemsElectrified aircraft propulsion (EAP) systems hold potential for the reduction of aircraft fuel burn, emissions, and noise. Currently, NASA and other organizations are actively working to identify and mature technologies necessary to bring EAP designs to reality. This paper specifically focuses on…20 pp20190031945
- Control Technology Needs for Electrified Aircraft Propulsion SystemsElectrified aircraft propulsion (EAP) systems hold potential for the reduction of aircraft fuel burn, emissions, and noise. Currently, NASA and other organizations are actively working to identify and mature technologies necessary to bring EAP designs to reality. This paper specifically focuses on…12 pp20190026570
- Control-system techniques for improved departure/spin resistance for fighter aircraftThis paper summarizes some fundamental information on control-system effects on controllability of highly maneuverable aircraft at high angles of attack and techniques for enhancing fighter aircraft departure/spin resistance using control-system design. The discussion includes (1) a brief review of…70 ppNASA-TP-1689
- Cooled variable-area radial turbine technology programThe objective of this study was a conceptual evaluation and design analyses of a cooled variable-area radial turbine capable of maintaining nearly constant high efficiency when operated at a constant speed and pressure ratio over a range of flows corresponding to 50- to 100-percent maximum engine…308 ppNASA-CR-165408
- Cooling of Electric Motors Used for Propulsion on SCEPTORNASA is developing a suite of hybrid-electric propulsion technologies for aircraft. These technologies have the benefit of lower emissions, diminished noise, increased efficiency, and reduced fuel burn. These will provide lower operating costs for aircraft operators. Replacing internal combustion…18 pp20170004363
- Cooling Tests of an Airplane Equipped with an NACA Cowling and a Wing-duct Cooling SystemCooling tests were made of a Northrop A-17A attack airplane successively equipped with a conventional.NACA cowling and with a wing-duct cooling system. The method of cooling the engine by admitting air from the propeller slipstream into wing ducts, passing it first through the accessory compartment…37 ppNACA-TN-813
- Cooperative control theory and integrated flight and propulsion controlThis report documents the activities and research results obtained under a grant (NAG3-998) from the NASA Lewis Research Center. The focus of the research was the investigation of dynamic interactions between airframe and engines for advanced ASTOVL aircraft configurations, and the analysis of the…103 ppNASA-CR-197493
- Correaltion of full-scale drag predictions with flight measurements on the C-141A aircraft. Phase 2: Wind tunnel test, analysis, and prediction techniques. Volume 1: Drag predictions, wind tunnel data analysis and correlationThe degree of cruise drag correlation on the C-141A aircraft is determined between predictions based on wind tunnel test data, and flight test results. An analysis of wind tunnel tests on a 0.0275 scale model at Reynolds number up to 3.05 x 1 million/MAC is reported. Model support interference…165 ppNASA-CR-2333
- Correlation of airloads on a two-bladed helicopter rotorAirloads measured on a two-bladed helicopter rotor in flight during the Ames' Tip Aerodynamic and Acoustic Test are compared with calculations from a comprehensive helicopter analysis (CAMRAD/JA), and the pressures compared with calculations from a full-potential rotor code (FPR). The flight-test…30 ppNASA-TM-103982
- Correlation of full-scale drag predictions with flight measurements on the C-141A aircraft : Phase 2: Wind tunnel tests, analysis, and prediction techniques. Volume 2: Wind tunnel test and basic dataA research program has been conducted to determine the degree of cruise drag correlation on the C-141A aircraft between predictions based on wind tunnel test data, and flight test results. Information is presented on the wind tunnel test program and basic aerodynamic data on the C-141A wind-tunnel…187 ppNASA-CR-2334
- Correlation of low speed wind tunnel and flight test data for V/STOL aircraftThe XV-5B fan-in-wing aircraft and the Y0V-10 RCF rotating cylinder flap aircraft were subjected to wind tunnel tests. These tests were conducted specifically to provide for correlation between wind tunnel and inflight aerodynamics and noise test data. Correlation between aerodynamic and noise data…12 ppNASA-TM-X-62423
- Correlation of Predicted and Flight Derived Stability and Control Derivatives with Particular Application to Tailless Delta Wing ConfigurationsFlight derived longitudinal and lateral-directional stability and control derivatives were compared to wind-tunnel derived values. As a result of these comparisons, boundaries representing the uncertainties that could be expected from wind-tunnel predictions were established. These boundaries…41 ppNASA-TM-81361
- Correlation of wind-tunnel and flight-test aerodynamic data for five V/STOL aircraftCorrelation of wind tunnel and flight test aerodynamic data for five V/STOL aircraft33 ppAGARD-520
- Correlations Among Ice Measurements, Impingement Rates Icing Conditions, and Drag Coefficients for Unswept NACA 65A004 AirfoilAn empirical relation has been obtained by which the change in drag coefficient caused by ice formations on an unswept NACA 65AO04 airfoil section can be determined from the following icing and operating conditions: icing time, airspeed, air total temperature, liquid-water content, cloud droplet…46 ppNACA-TN-4151
- Cost consideration for aircraft configuration changes, 1The costs of improvements in aircraft drag reduction design changes are outlined in the context of production decisions. A drag reduction design with increased airframe weight requires cost increases for direct labor, overhead and direct expenses, plus general and administrative expenses.5 pp19760003934
- Coupled rotor/fuselage dynamic analysis of the AH-1G helicopter and correlation with flight vibrations dataUnder a research program designated Design Analysis Methods for VIBrationS (DAMVIBS), existing analytical methods are used for calculating coupled rotor-fuselage vibrations of the AH-1G helicopter for correlation with flight test data from an AH-1G Operational Load Survey (OLS) test program. The…154 ppNASA-CR-181723
- Coupled Vortex-Lattice Flight Dynamic Model with Aeroelastic Finite-Element Model of Flexible Wing Transport Aircraft with Variable Camber Continuous Trailing Edge Flap for Drag ReductionThis paper presents a coupled vortex-lattice flight dynamic model with an aeroelastic finite-element model to predict dynamic characteristics of a flexible wing transport aircraft. The aircraft model is based on NASA Generic Transport Model (GTM) with representative mass and stiffness properties to…38 pp20140008923
- Crew Factors in Flight Operations XV: Alertness Management in General Aviation Education ModuleRegional operations encompass a broad range of pilots and equipment. This module is intended to help all those involved in regional aviation, including pilots, schedulers, dispatchers, maintenance technicians, policy makers, and others, to understand the physiological factors underlying fatigue,…152 ppNASA/TM-2002-211394
- Critical Mach Numbers of Thin Airfoil Sections with Plain FlapsCritical Mach number as function of lift coefficient is determined for certain moderately thick NACA low-drag airfoils. Results, given graphically, included calculations on same airfoil sections with plain flaps for small flap deflections. Curves indicate optimum critical conditions for airfoils…27 ppNACA-WR-W-2
- Cruise Slotted Wing Design with Natural Laminar Flow for Transonic Commercial Transport AircraftThe present computational study investigates the aerodynamic design and analysis of cruise slotted wings with natural laminar flow for transonic transport aircraft. The cruise slotted wing is a multielement wing concept that features an intermediate slot to achieve greater aft loading relative to…22 pp
- Cruise Slotted Wing Design with Natural Laminar Flow for Transonic Commercial Transport AircraftThe present computational study investigates the aerodynamic design and analysis of cruise slotted wings with natural laminar flow for transonic transport aircraft. The cruise slotted wing is a multielement wing concept that features an intermediate slot to achieve greater aft loading relative to…13 pp
- Current Methods for Modeling and Simulating Icing Effects on Aircraft Performance, Stability and ControlIcing alters the shape and surface characteristics of aircraft components, which results in altered aerodynamic forces and moments caused by air flow over those iced components. The typical effects of icing are increased drag, reduced stall angle of attack, and reduced maximum lift. In addition to…28 ppNASA/TM-2008-215453
- Current Methods Modeling and Simulating Icing Effects on Aircraft Performance, Stability, ControlIcing alters the shape and surface characteristics of aircraft components, which results in altered aerodynamic forces and moments caused by air flow over those iced components. The typical effects of icing are increased drag, reduced stall angle of attack, and reduced maximum lift. In addition to…11 ppAIAA Paper-44650-413
- Curved centerline air intake for a gas turbine engineAn inlet for a gas turbine engine was disposed about a curved centerline for the purpose of accepting intake air that is flowing at an angle to engine centerline and progressively turning that intake airflow along a curved path into alignment with the engine. This curved inlet is intended for use…6 pp19810006484
- Curved flow wind tunnnel test of F-18 aircraftThe curved flow capability of a stability wind tunnel was used to investigate the lateral directional characteristics of an F-18 aircraft. The model is described and the procedures used to obtain and correct the data and a graphical presentation of the results are presented. The results include…298 ppNASA-CR-169345
- DARPA/AFRL/NASA Smart Wing Second Wind Tunnel Test ResultsTo quantify the benefits of smart materials and structures adaptive wing technology, Northrop Grumman Corp. (NGC) built and tested two 16% scale wind tunnel models (a conventional and a "smart" model) of a fighter/attack aircraft under the DARPA/AFRL/NASA Smart Materials and Structures Development…11 pp
- De-icing of the altitude wind tunnel turning vanes by electro-magnetic impulseThe Altitude Wind Tunnel at the NASA-Lewis facility is being proposed for a refurbishment and moderization. Two major changes are: (1) the increasing of the test section Mach number to 0.90, and (2) the addition of spray nozzles to provide simulation of flight in icing clouds. Features to be…48 pp19860017819
- Decoupler pylon: wing/store flutter suppressorA device for suspending a store from a support such as an aircraft wing and more specifically for increasing the flutter speed of an aircraft flying with attached store and reducing the sensitivity of flutter to changes in the pitch inertia and center of gravity location of the store is described.…9 pp19820024497
- Decoupling control synthesis for an oblique-wing aircraftInterest in oblique-wing aircraft has surfaced periodically since the 1940's. This concept offers some substantial aerodynamic performance advantages but also has significant aerodynamic and inertial cross-coupling between the aircraft longitudinal and lateral-directional axes. This paper presents…14 ppNASA-TM-86801
- Defining Services, Functions, and Capabilities for an Advanced Air Mobility (AAM) In-time Aviation Safety Management System (IASMS)NASA’s vision for Advanced Air Mobility (AAM) Mission is to help emerging aviation markets to safely develop an air transportation system that moves people and cargo between places previously not served or underserved by aviation. The integration of new operational paradigms and vehicle classes in…14 pp
- Definition of propulsion system for V/STOL research and technology aircraftWind tunnel test support, aircraft contractor support, a propulsion system computer card deck, preliminary design studies, and propulsion system development plan are reported. The Propulsion system consists of two lift/cruise turbofan engines, one turboshaft engine and one lift fan connected…109 pp19770013166
- Deicing and Anti-Icing UniteWith funding from Glenn's Small Business Innovation Research (SBIR) program, Cox & Company, Inc., built an ice protection system that combines thermal anti-icing and mechanical deicing to keep airfoils (wings and other lifting surfaces) clear of ice. Cox's concept was to combine an anti-icing…2 pp20020080248
- Design and Conduct of a Windshear Detection Flight ExperimentA description of the design and conduct of a series of flight experiments which tested the performance of candidate windshear detection devices is presented. With prototype windshear sensors installed, a NASA Boeing 737 test aircraft conducted numerous low altitude penetrations of microburst…14 ppAIAA-92-4092
- Design and construction of a remote piloted flying wingCurrently, there is a need for a high-speed, high-lift civilian transport. Although unconventional, a flying wing could fly at speeds in excess of Mach 2 and still retain the capacity of a 747. The design of the flying wing is inherently unstable since it lacks a fuselage and a horizontal tail. The…187 pp19950006282
- Design and Control of an Experimental Tilt-Wing AircraftIn this project, work has been done in the field of conceptual design of experimental tiltrotors. The main tools that have been used are NDARC (NASA Design and Analysis of Rotorcraft) and SIMPLI-FLYD. NDARC is a conceptual design tool for rotorcraft, and it is used to find trim points under various…26 ppNASA/CR-2017-219456
- Design and Demonstration of Emergency Control Modes for Enhanced Engine PerformanceA design concept is presented for developing control modes that enhance aircraft engine performance during emergency flight scenarios. The benefits of increased engine performance to overall vehicle survivability during these situations may outweigh the accompanied elevated risk of engine failure.…51 pp20140000929
- Design and Development of a 200-kW Turbo-Electric Distributed Propulsion TestbedThe National Aeronautics and Space Administration (NASA) Armstrong Flight Research Center (AFRC) (Edwards, California) is developing a Hybrid-Electric Integrated Systems Testbed (HEIST) Testbed as part of the HEIST Project, to study power management and transition complexities, modular…17 pp20160009765
- Design and Development of a Deep Acoustic Lining for the 40-by 80-Foot Wind Tunnel Test SectionThe work described in this report has made effective use of design teams to build a state-of-the-art anechoic wind-tunnel facility. Many potential design solutions were evaluated using engineering analysis, and computational tools. Design alternatives were then evaluated using specially developed…61 ppNASA/TP-2002-211850
- Design and evaluation of a robust dynamic neurocontroller for a multivariable aircraft control problemThe design of a dynamic neurocontroller with good robustness properties is presented for a multivariable aircraft control problem. The internal dynamics of the neurocontroller are synthesized by a state estimator feedback loop. The neurocontrol is generated by a multilayer feedforward neural…9 ppNASA-TM-105579
- Design and evaluation of an integrated Quiet, Clean General Aviation Turbofan (QCGAT) engine and aircraft propulsion systemThe design was based on the LTS-101 engine family for the core engine. A high bypass fan design (BPR=9.4) was incorporated to provide reduced fuel consumption for the design mission. All acoustic and pollutant emissions goals were achieved. A discussion of the preliminary design of a business jet…238 pp19810023604
- Design and fabrication of forward-swept counterrotation blade configuration for wind tunnel testingWork performed by GE Aircraft on advanced counterrotation blade configuration concepts for high speed turboprop system is described. Primary emphasis was placed on theoretically and experimentally evaluating the aerodynamic, aeromechanical, and acoustic performance of GE-defined counterrotating…172 pp19940024007
- Design and fabrication of large suction panels with perforated surfaces for laminar flow control testing in a transonic wind tunnelConsiderable progress has been made in the development of perforated suction surface material for laminar flow control applications. Electron-beam perforated titaniuum skin was used as the suction surface. Critical issues related to suction panel manufacturing were identified and largely resolved.…19860020343
- Design and flight test of the Propulsion Controlled Aircraft (PCA) flight control system on the NASA F-15 test aircraftThis report describes the design, development and flight testing of the Propulsion Controlled Aircraft (PCA) flight control system performed at McDonnell Douglas Aerospace (MDA), St. Louis, Missouri and at the NASA Dryden Flight Research Facility, Edwards Air Force Base, California. This research…45 pp19940022929
- Design and physical characteristics of the Transonic Aircraft Technology (TACT) research aircraftThe Transonic Aircraft Technology (TACT) research program provided data necessary to verify aerodynamic concepts, such as the supercritical wing, and to gain the confidence required for the application of such technology to advanced high performance aircraft. An F-111A aircraft was employed as the…32 pp19790005843
- Design and Stability of an On-Orbit Attitude Control System Using Reaction Control ThrustersBasic principles for the design and stability of a spacecraft on-orbit attitude control system employing on-off Reaction Control System (RCS) thrusters are presented. Both vehicle dynamics and the control system actuators are inherently nonlinear, hence traditional linear control system design…26 ppM16-4984
- Design and testing of an oblique all-wing supersonic transportThis report describes the preliminary design of an Oblique All-Wing (OAW) supersonic transport and a corresponding wind-tunnel model that was tested in the NASA Ames 9- by 7-Foot supersonic wind tunnel. The main goal was the determination of the cruise performance (lift/drag ratio) of a…5 pp19950006372
- Design and Testing of Drag Minimization and Maneuver Load Alleviation Control Laws for the IAWTM Wind Tunnel TestThis paper presents the design and experimental testing of drag minimization and maneuver load alleviation (MLA) controllers for high aspect ratio wing wind tunnel model. The controllers are developed for the Integrated Adaptive Wing Technology Maturation (IAWTM) wind tunnel tests at Langley…29 pp
- Design and Testing of Gust Load Alleviation Control Laws for the IAWTM Wind Tunnel TestThis paper summarizes the design and testing of gust load alleviation (GLA) control laws developed for the Integrated Adaptive Wing Technology Maturation (IAWTM) wind tunnel test campaign at NASA’s Langley Research Center Transonic Dynamics Tunnel (TDT). The IAWTM program is a joint NASA and Boeing…34 pp
- Design Considerations for the Next Generation of General Aviation DesignsThis paper discusses the results of research conducted at NASA Langley Research Center during two summer programs during 1994 and 1995. These programs were the NASA Advanced Design Program and the Langley Research Summer Scholars program. The work was incorporated in a three phase project at…12 pp19970003092
- Design criteria for flightpath and airspeed control for the approach and landing of STOL aircraftA flight research program was conducted to assess requirements for flightpath and airspeed control for glide-slope tracking during a precision approach and for flare control, particularly as applied to powered-lift, short takeoff and landing (STOL) aircraft. Ames Research Center's Augmentor Wing…100 ppNASA-TP-1911
- Design integration and noise studies for jet STOL aircraft. Volume 1: Program summaryThis program was undertaken to develop, through analysis, design, experimental static testing, wind tunnel testing, and design integration studies, an augmentor wing jet flap configuration for a jet STOL transport aircraft having maximum propulsion and aerodynamic performance with minimum noise…58 pp19720020357
- Design Methodology for Multi-Element High-Lift Systems on Subsonic Civil Transport AircraftThe choice of a high-lift system is crucial in the preliminary design process of a subsonic civil transport aircraft. Its purpose is to increase the allowable aircraft weight or decrease the aircraft's wing area for a given takeoff and landing performance. However, the implementation of a high-lift…109 pp19960054343
- Design of a composite wing extension for a general aviation aircraftA composite wing extension was designed for a typical general aviation aircraft to improve lift curve slope, dihedral effect, and lift to drag ratio. Advanced composite materials were used in the design to evaluate their use as primary structural components in general aviation aircraft. Extensive…50 pp19840024307
- Design of a control configured tanker aircraftThe benefits that accrue from using control configured vehicle (CCV) concepts were examined along with the techniques for applying these concepts to an advanced tanker aircraft design. Reduced static stability (RSS) and flutter mode control (FMC) were the two primary CCV concepts used in the…14 pp
- Design of a Low Cost Short Takeoff-vertical Landing Export Fighter/attack AircraftThe design of a supersonic short takeoff and vertical landing (STOVL) aircraft is presented that is suitable for export. An advanced four poster, low bypass turbofan engine is to be used for propulsion. Preliminary aerodynamic analysis is presented covering a determination of CD versus CL, CD…91 pp19900015816
- Design of a multivariable integrated control for a supersonic propulsion systemAn inlet/engine/nozzle integrated control mode for the propulsion system of an advanced supersonic commercial aircraft was studied. Results show that integration of these control functions can result in both operational and performance benefits for the propulsion system. For example, this…13 pp19810003584
- Design of a Slowed-Rotor Compound Helicopter for Future Joint Service MissionsA slowed-rotor compound helicopter has been synthesized using the NASA Design and Analysis of Rotorcraft (NDARC) conceptual design software. An overview of the design process and the capabilities of NDARC are presented. The benefits of trading rotor speed, wing-rotor lift share, and trim strategies…16 ppARC-E-DAA-TN1155
- Design of a transonically profiled wingThe application of well known design concepts with the combined use of thick transonic profiles to aircraft wing design was investigated. Optimization in terms of weight and operational costs was emphasized. It is shown that the usual design criteria and concepts are too restricted and do not…63 pp19780024109
- Design of a turbofan powered regional transport aircraftThe majority of the market for small commercial transport aircraft is dominated by high-efficiency, propeller-driven aircraft of non-U.S. manufacture. During the past year senior student design teams at Purdue developed and then responded to a Request For Proposal (RFP) for a regional transport…6 pp19930020532
- Design of Combustor for Long-range Ram-jet Engine and Performance of Rectangular AnalogThe report describes the design of a piloted combustor intended for a ram-jet engine of long flight range. The unit comprises a large annular basket of V-type cross-section, the inner surface of which is slotted and bent into small V-gutters. At the trailing edge of the basket, eight V-gutters are…22 ppNACA-RM-E53K13
- Design of helicopter rotor blades for optimum dynamic characteristicsThe mass and stiffness distributions for helicopter rotor blades are tailored in such a way to give a predetermined placement of blade natural frequencies. The optimal design is pursued with respect of minimum weight, sufficient inertia, and reasonable dynamic characteristics. Finite element…146 ppNASA-CR-176076
- Design of helicopter rotor blades for optimum dynamic characteristicsThe optimal design of helicopter rotor blades is addressed. The forced response of an initial (i.e., non-optimized) blade to those of a final (optimized) blade are compared. Response of starting design and optimal designs for varying forcing frequencies, blade response to harmonics of rotor speed,…30 ppNASA-CR-175380
- Design of Rail Instrumentation for Wind Tunnel Sonic Boom Measurements and Computational-Experimental ComparisonsAn innovative pressure rail concept for wind tunnel sonic boom testing of modern aircraft configurations with very low overpressures was designed with an adjoint-based solution-adapted Cartesian grid method. The computational method requires accurate free-air calculations of a test article as well…2 ppARC-E-DAA-TN4517
- Design, Development, and Flight Evaluation of Pilot Displays and Long-Track Control for Wake Surfing ApplicationsFrom April to May 2017, the National Aeronautics and Space Administration Armstrong Flight Research Center completed a series of flights with a trail C-20A airplane surfing in the wake of a Gulfstream III airplane using a commercially available datalink as the primary communication between the two…17 ppAFRC-E-DAA-TN54320
- Design, fabrication, and static testing of Attached Inflatable Decelerator /AID/ modelsDesign, fabrication and static testing of attached inflatable decelerator models for supersonic wind tunnel evaluation85 pp19710013062
- Design, Fabrication, and Testing of Composite Energy-Absorbing Keel Beams for General Aviation Type AircraftA lightweight energy-absorbing keel-beam concept was developed and retrofitted in a general aviation type aircraft to improve crashworthiness performance. The energy-absorbing beam consisted of a foam-filled cellular structure with glass fiber and hybrid glass/kevlar cell walls. Design, analysis,…28 pp20030004235
- Design, implementation and flight testing of PIF autopilots for general aviation aircraftThe designs of Proportional-Integrated-Filter (PIF) auto-pilots for a General Aviation (NAVION) aircraft are presented. The PIF autopilot uses the sampled-data regulator and command generator tracking to determine roll select, pitch select, heading select, altitude select and localizer/glideslope…180 ppNASA-CR-3709
- Designs and Technology Requirements for Civil Heavy Lift RotorcraftThe NASA Heavy Lift Rotorcraft Systems Investigation examined in depth several rotorcraft configurations for large civil transport, designed to meet the technology goals of the NASA Vehicle Systems Program. The investigation identified the Large Civil Tiltrotor as the configuration with the best…26 pp20080047712
- Determination of Aircraft Antenna Loads Produced by Natural Icing ConditionsA flight investigation was made to determine the effect of distance flown in the icing region, antenna length, and antenna angle on the tension occurring in aircraft antennae while in regions of aircraft icing. The experimental antennas were of lengths ranging from 15 to 43 feet and were placed at…25 ppNACA-RM-E7H26a
- Determination of Boundary-Layer Transition on Three Symmetrical Airfoils in the NACA Full-Scale Wind TunnelFor the purpose of studying the transition from laminar to turbulent flow, boundary-layer measurements were made in the NACA full-scale wind tunnel on three symmetrical airfoils of NACA 0009, 0012, and 0018 sections. The effects of variations in lift coefficient, Reynolds number, and airfoil…22 ppNACA-TR-637
- Determination of control-surface characteristics from NACA plain-flap and tab dataThe data from previous NACA pressure-distribution investigations of plain flaps and tabs with sealed gaps have been analyzed and are presented in this paper in a form readily applicable to the problems of control-surface design. The experimentally determined variation of aerodynamic parameters with…28 ppNACA-TR-721
- Determination of control-surface characteristics from NACA plain-flap and tab dataThe data from previous NACA pressure-distribution investigations of plain flaps and tabs have been analyzed and are presented in this paper in a form readily applicable to the problems of control-surface design. The experimentally determined variation of aerodynamic parameters with flap chord and…47 ppNACA-TN-796
- Determination of flight characteristics of supersonic transports during the landing approach with a large jet transport in-flight simulatorFlight characteristics of supersonic transports during landing approach with large jet transport in flight simulator189 ppNASA-TN-D-3971
- Determination of longitudinal aerodynamic derivatives using flight data from an icing research aircraftA flight test was performed with the NASA Lewis Research Center's DH-6 icing research aircraft. The purpose was to employ a flight test procedure and data analysis method, to determine the accuracy with which the effects of ice on aircraft stability and control could be measured. For simplicity,…20 pp19890005750
- Determination of Stability and Control Derivatives using Computational Fluid Dynamics and Automatic DifferentiationWith the recent interest in novel control effectors there is a need to determine the stability and control derivatives of new aircraft configurations early in the design process. These derivatives are central to most control law design methods and would allow the determination of closed-loop…18 ppAIAA Paper 99-3136
- Determination of stability and control parameters of a general aviation airplane from flight dataValues for the stability and control parameters for a general aviation airplane were determined from flight data. Lateral and longitudinal transient maneuvers were analyzed by the equation error and output error methods. There was a good agreement between the parameters extracted from flight data…48 pp19830018573
- Determination of the level flight performance of propeller-driven aircraftA flight test method to determine the level flight performance of propeller driven aircraft is reported that measures the amount of power it takes to overcome a known increment of added drag to maintain steady state flight conditions to determine overall drag and propeller efficiency of a general…4 pp19760003939
- Determining Aircraft Moments of Inertia from Flight Test DataFlight test maneuver design and dynamic modeling techniques were developed for determining aircraft moments of inertia from flight test data. Full nonlinear rigid-body rotational equations of motion were used in the analysis, with aerodynamic moment dependencies modeled by linear expansions in the…18 pp
- Determining Aircraft Moments of Inertia from Flight Test DataFlight test maneuvers and dynamic modeling techniques were developed for determining aircraft moments of inertia from flight test data. Full nonlinear rigid-body rotational equations of motion were used in the analysis, with aerodynamic moment dependencies modeled by linear expansions in the…28 pp
- Developing a workstation-based, real-time simulation for rapid handling qualities evaluations during designThis paper describes the Rapid Aircraft DynamIcs AssessmeNt (RADIAN) project - an integration of the Aircraft SYNThesis (ACSTNT) design code with the USAD DATCOM code that estimates stability derivatives. Both of these codes are available to universities. These programs are then linked to flight…10 pp19950023914
- Development and Flight Testing of a Neural Network Based Flight Control System on the NF-15B AircraftThe Intelligent Flight Control System (IFCS) project at the NASA Dryden Flight Research Center, Edwards AFB, CA, has been investigating the use of neural network based adaptive control on a unique NF-15B test aircraft. The IFCS neural network is a software processor that stores measured aircraft…33 pp
- Development and Operation of an Automatic Rotor Trim Control System for the UH-60 Individual Blade Control Wind Tunnel TestAn automatic rotor trim control system was developed and successfully used during a wind tunnel test of a full-scale UH-60 rotor system with Individual Blade Control (IBC) actuators. The trim control system allowed rotor trim to be set more quickly, precisely and repeatably than in previous wind…22 ppARC-E-DAA-TN1140
- Development and Testing of a High Stability Engine Control (HISTEC) SystemFlight tests were recently completed to demonstrate an inlet-distortion-tolerant engine control system. These flight tests were part of NASA's High Stability Engine Control (HISTEC) program. The objective of the HISTEC program was to design, develop, and flight demonstrate an advanced integrated…16 ppNASA/TM-1998-206562
- Development and testing of a unique carousel wind tunnel to experimentally determine the effect of gravity and the interparticle force on the physics of wind-blown particlesIn the study of planetary aeolian processes the effect of gravity is not readily modeled. Gravity appears in the equations of particle motion along with the interparticle forces but the two are not separable. A wind tunnel that perimits multiphase flow experiments with wind blown particles at…6 pp19890005651
- Development of 2 underseat energy absorbers for application to crashworthy passenger seats for general aviation aircraftThis report presents the methodology and results of a program conducted to develop two underseat energy absorber (E/A) concepts for application to nonadjustable crashworthy passenger seats for general aviation aircraft. One concept utilizes an inflated air bag, and the other, a convoluted sheet…103 pp19840024297
- Development of a Flow Field for Testing a Boundary-Layer-Ingesting PropulsorThe test section of the 8- by 6-Foot Supersonic Wind Tunnel at NASA Glenn Research Center was modified to produce the test conditions for a boundary-layer-ingesting propulsor. A test was conducted to measure the flow properties in the modified test section before the propulsor was installed.…20 pp20170008730
- Development of a low risk augmentation system for an energy efficient transport having relaxed static stabilityAn augmentation system for a 230 passenger, twin engine aircraft designed with a relaxation of conventional longitudinal static stability was developed. The design criteria are established and candidate augmentation system control laws and hardware architectures are formulated and evaluated with…358 ppNASA-CR-159166
- Development of a Maxwell X-57 High Lift Motor Reference DesignNASA's all-electric X-57 airplane will utilize 14 electric motors, of which 12 are exclusively for lift augmentation during takeoff and landing. This report covers the design and development process taken to create an open reference model representative of the 12 lift augmenting motors. A combined…24 pp20190029267
- Development of a multipurpose smart recorder for general aviation aircraftAn intelligent flight recorder, called the Smart Recorder, was fabricated and installed on a King Air aircraft used in standard commercial charter service. This recorder was used for collection of data toward two objectives: (1) the characterization of the typical environment encountered by the…93 pp19880015253
- Development of an active fly-by-wire flight control systemA summary of the YF-16 flight control system is presented. The basic functions of the flight control system are discussed, as well as the unique features such as Relaxed Static Longitudinal Stability (RSS), Fly By Wire (FBW), and Side Stick Pilot's Controller (SSC). In addition, the basic…15 pp
- Development of an Active Twist Rotor for Wind: Tunnel Testing (NLPN97-310The development of the Active Twist Rotor prototype blade for hub vibration and noise reduction studies is presented in this report. Details of the modeling, design, and manufacturing are explored. The rotor blade is integrally twisted by direct strain actuation. This is accomplished by…18 pp20000004379
- Development of an advanced pitch active control system and a reduced area horizontal tail for a wide-body jet aircraftThe development of an advanced pitch active control system (PACS) and a reduced area horizontal tail for a wide-body jet transport (L-1011) with a flying horizontal stabilizer is discussed. The advanced PACS control law design objectives were to provide satisfactory handling qualities for aft c.g.…64 ppNASA-CR-172283
- Development of an advanced pitch active control system for a wide body jet aircraftAn advanced PACS control law was developed for a commercial wide-body transport (Lockheed L-1011) by using modern control theory. Validity of the control law was demonstrated by piloted flight simulation tests on the NASA Langley visual motion simulator. The PACS design objective was to develop a…163 ppNASA-CR-172277
- Development of circulation control technology for powered-lift STOL aircraftThe flow entraining capabilities of the Circulation Control Wing high lift system were employed to provide an even stronger STOL potential when synergistically combined with upper surface mounted engines. The resulting configurations generate very high supercirculation lift in addition to a…47 pp19880008224
- Development of crashworthy passenger seats for general-aviation aircraftTwo types of energy absorbing passenger seat concepts suitable for installation in light twin-engine fixed wing aircraft were developed. An existing passenger seat for such an aircraft was used to obtain the envelope constraints. Ceiling suspended and floor supported seat concept designs were…120 pp19790022993
- Development of Criteria for the Design of a Low Noise Level General Aviation PropellerThe theoretical and experimental investigation of general aviation propellers is considered. The objective is to improve noise generation characteristics without loss of performance.101 pp19760025089
- Development of EPA aircraft piston engine emission standardsPiston engine light aircraft are significant sources of carbon monoxide in the vicinity of high activity general aviation airports. Substantial reductions in carbon monoxide were achieved by fuel mixture leaning using improved fuel management systems. The air quality impact of the hydrocarbon and…22 pp19770010139
- Development of Experimental Icing Simulation Capability for Full-Scale Swept Wings: Hybrid Design Process, Years 1 and 2This report presents the key results from the first two years of a program to develop experimental icing simulation capabilities for full-scale swept wings. This investigation was undertaken as a part of a larger collaborative research effort on ice accretion and aerodynamics for large-scale swept…122 pp20180001238
- Development of flight testing techniquesA list of students involved in research on flight analysis and development is given along with abstracts of their work. The following is a listing of the titles of each work: Longitudinal stability and control derivatives obtained from flight data of a PA-30 aircraft; Aerodynamic drag reduction…8 pp19860019464
- Development of Handling Qualities Criteria for Rotorcraft with Externally Slung LoadsPiloted simulations were performed on the NASA-Ames Vertical Motion Simulator (VMS) to explore handling qualities issues for large cargo helicopters, particularly focusing on external slung load operations. The purpose of this work was based upon the need to include handling qualities criteria for…173 pp20070009837
- Development of longitudinal handling qualities criteria for large advanced supersonic aircraftLongitudinal handling qualities criteria in terms of airplane response characteristics were developed. The criteria cover high speed cruise maneuvering, landing approach, and stall recovery. Data substantiating the study results are reported.215 pp19750012273
- Development of longitudinal handling qualities criteria for large advanced supersonic aircraftA piloted simulation study was conducted with the aim of advancing the development of longitudinal handling qualities criteria for large supersonic cruise aircraft. The areas of study investigated included high-speed cruise maneuvering, and stall-recovery control power. Comparisons were made with…22 pp19770011062
- Development, Implementation, and Pilot Evaluation of a Model-Driven Envelope Protection System to Mitigate the Hazard of In-Flight Ice Contamination on a Twin-Engine Commuter AircraftFatal loss-of-control accidents have been directly related to in-flight airframe icing. The prototype system presented in this report directly addresses the need for real-time onboard envelope protection in icing conditions. The combination of prior information and real-time aerodynamic parameter…126 pp20150000859
- Development, simulation validation, and wind tunnel testing of a digital controller system for flutter suppressionFlutter suppression (FS) is one of the active control concepts being investigated by the AFW program. The design goal for FS control laws was to increase the passive flutter dynamic pressure by 30 percent. In order to meet this goal, the FS control laws had to be capable of suppressing both…32 pp19910013023
- Developments in aircraft jet noise technologySignificant developments in two areas of jet noise technology are described: the development of jet noise technology relative to coannular nozzles of all types, and a recent approach to the analysis of flight effects that appears to allow simulated flight effects results to be transformed to actual…16 pp19770011164
- DHC-6 Twin Otter Tailplane Airfoil Section Testing in the Ohio State University 7x10 Wind TunnelIce contaminated tailplane stall (ICTS) has been found to be responsible for 16 accidents with 139 fatalities over the last three decades, and is suspected to have played a role in other accidents and incidents. The need for fundamental research in this area has been recognized at three…114 pp20000120451
- Digital Signal Conditioning for Flight Test InstrumentationThis volume in the AGARD Flight Instrumentation Series provides flight test instrumentation engineers with an introduction to digital measurement processes on aircraft. Flight test instrumentation systems are rapidly evolving from analog-intensive to digital-intensive systems, including the use of…88 ppNASA-TM-101739
- Directions in propulsion controlDiscussed here is research at NASA Lewis in the area of propulsion controls as driven by trends in advanced aircraft. The objective of the Lewis program is to develop the technology for advanced reliable propulsion control systems and to integrate the propulsion control with the flight control for…18 pp19920013287
- Discussion of the results of the boundary-layer tests of an airfoil fitted with a rotary cylinderThe results of the velocity measurements in the boundary layer described in NACA-TM 411 are here discussed in greater detail. The measurements made were of the velocity distribution in the vicinity of an airfoil model fitted with a rotary cylinder and were undertaken for the purpose of obtaining a…17 ppNACA-TM-424
- Distortion Tolerant Control Demonstrated in FlightFuture aircraft turbine engines, both commercial and military, will have to be able to successfully accommodate expected increased levels of steady-state and dynamic engine-face distortion. Advanced tactical aircraft are likely to use thrust vectoring for enhanced aircraft maneuverability. As a…3 pp
- Distributed Propulsion VehiclesSince the introduction of large jet-powered transport aircraft, the majority of these vehicles have been designed by placing thrust-generating engines either under the wings or on the fuselage to minimize aerodynamic interactions on the vehicle operation. However, advances in computational and…11 pp20100036222
- Distributed Turboelectric Propulsion for Hybrid Wing Body AircraftMeeting future goals for aircraft and air traffic system performance will require new airframes with more highly integrated propulsion. Previous studies have evaluated hybrid wing body (HWB) configurations with various numbers of engines and with increasing degrees of propulsion-airframe…12 pp20080021214
- Dividers for reduction of aerodynamic drag of vehicles with open cavitiesA drag-reduction concept for vehicles with open cavities includes dividing a cavity into smaller adjacent cavities through installation of one or more vertical dividers. The dividers may extend the full depth of the cavity or only partial depth. In either application, the top of the dividers are…12 pp20080008721
- Douglas Experience in Flight Flutter TestingDouglas Aircraft Company experience in flight flutter testing is reviewed briefly, with comments on state-of-the-art excitation and instrumentation techniques used up to the present time. The limitations of previous techniques are discussed with emphasis on the problem of: (1) establishing a…6 pp19760003024
- Drag and wear characteristics of various skid materials on dissimilar lakebed surfaces during the slideout of the X-15 airplaneFriction coefficients and wear characteristics for X-15 aircraft skid landing gear29 pp19660008883
- Drag Coefficient of Water Droplets Approaching the Leading Edge of an AirfoilThis work presents results of an experimental study on droplet deformation and breakup near the leading edge of an airfoil. The experiment was conducted in the rotating rig test cell at the Instituto Nacional de Tecnica Aeroespacial (INTA) in Madrid, Spain. An airfoil model was placed at the end of…22 pp20140010645
- Drag Determination of the Forward Component of a Tricycle Landing GearWind-tunnel tests were performed to determine the drag of the front-wheel arrangements of several types of tricycle landing gear. One wheel was tested in arrangements to simulate both nonretracted and partially retracted types. The landing gears were tested in conjunction with a fuselage, and the…29 ppNACA-TN-788
- Drag Measurements at Transonic Speeds of NACA 65-009 Airfoils Mounted on a Freely Falling Body to Determine the Effects of Sweepback and Aspect RatioDrag measurements at transonic speeds on rectangular airfoils and on airfoils swept back 450 are reported. These airfoils, which were mounted on cylindrical test bodies, are part of a series being tested in free drops from high altitude to determine the effect of variation of basic airfoil…15 ppNACA-RM-L6K08c
- Drag Measurements of a Protruding .50-caliber Machine Gun with Barrel Jacket RemovedTests were made in 8-ft high-speed wind tunnel to determine the drag reduction possible by eliminating the barrel jacket of a protruding 50-caliber aircraft gun. It was found that the drag of a standard aircraft gun protruding into the air stream at right angles to the flow can be reduced by 23% by…12 pp19930093504
- Drag of the complete configuration aerodynamic considerations, 2A number of drag items are related to the performance of a complete aircraft configuration. First, the effect of fuselage camber, wing and nacelle incidence are discussed from a viewpoint of design decision making. Second, the effect of overall cruise drag on the design gross and empty weight of…15 pp19760003935
- Drag reduction for glidersThe article discusses the causes of drag in gliders. The importance of maintaining laminar flow is emphasized. The problems of surface (or lack of) smoothness are outlined.17 pp19780016173
- Drag Reduction Through Distributed Electric PropulsionOne promising application of recent advances in electric aircraft propulsion technologies is a blown wing realized through the placement of a number of electric motors driving individual tractor propellers spaced along each wing. This configuration increases the maximum lift coefficient by…9 pp20140011507
- Drag reduction through higher wing loadingA reduction in wing area, thickness, and span increases wing loading and lowers parasitic drag for a typical light airplane by 10.5%.13 pp19760003921
- Drag Reduction: Back to BasicsAeronautical design engineering for general aviation aircraft considers the iteration of wind tunnel test data are lift, weight, drag, and thrust as the basic balancing factor in drag reduction efforts.8 pp19760003914
- Dragonfly Preparation for Powered Flight Wind Tunnel and CFD ModellingPreparation for Powered Flight (PPF) is a critical phase for Dragonfly, the National Aeronautics and Space Administration (NASA) mission to Saturn’s moon Titan. During PPF the descending lander has been lowered below the backshell and uses its rotors to remove or “despin” any residual yaw motion of…19 pp
- Dry wind tunnel systemThis invention is a ground flutter testing system without a wind tunnel, called Dry Wind Tunnel (DWT) System. The DWT system consists of a Ground Vibration Test (GVT) hardware system, a multiple input multiple output (MIMO) force controller software, and a real-time unsteady aerodynamic force…11 ppPatent Number: US-Patent-8,393,206
- Dynamic Analysis of the STARC-ABL Propulsion SystemIn the pursuit of Electrified Aircraft Propulsion (EAP), much of the attention is on the development of hybrid electric concept vehicles and their propulsion systems from a steady state performance perspective. While it is steady-state performance that largely determines the efficiency of civil air…21 pp20190030508
- Dynamic Analysis of the STARC-ABL Propulsion SystemIn the pursuit of Electrified Aircraft Propulsion (EAP), much of the attention is on the development of hybrid electric concept vehicles and their propulsion systems from a steady state performance perspective. While it is steady-state performance that largely determines the efficiency of civil air…20 pp20190032489
- Dynamic Analysis of the STARC-ABL Propulsion SystemIn the pursuit of Electrified Aircraft Propulsion (EAP), much of the attention is on the development of hybrid electric concept vehicles and their propulsion systems from a steady state performance perspective. While it is steady-state performance that largely determines the efficiency of civil air…14 pp20190030358
- Dynamic ground effects flight test of the NASA F-15 aircraftAerodynamic characteristics of an aircraft may significantly differ when flying close to the ground rather than when flying up and away. Recent research has also determined that dynamic effects (i.e., sink rate) influence ground effects (GE). A ground effects flight test program of the F-15…8 pp
- Dynamic stability and handling qualities tests on a highly augmented, statically unstable airplaneInitial envelope clearance and subsequent flight testing of a new, fully augmented airplane with an extremely high degree of static instability can place unusual demands on the flight test approach. Previous flight test experience with these kinds of airplanes is very limited or nonexistent. The…16 pp19870017487
- Dynamic stability of a helicopter with hinged rotor bladesThe present report is a study of the dynamic stability of a helicopter with hinged rotor blades under hovering conditions. While in this case perfect stability can in general not be obtained it is possible by means of design features to prolong the period of the spontaneous oscillations of the…20 ppNACA-TM-907
- Dynamic stall experiments on the NACA 0012 airfoilThe flow over a NACA 0012 airfoil undergoing large oscillations in pitch was experimentally studied at a Reynolds number of and over a range of frequencies and amplitudes. Hot-wire probes and surface-pressure transducers were used to clarify the role of the laminar separation bubble, to delineate…170 ppNASA-TP-1100
- Dynamic structural aeroelastic stability testing of the XV-15 tilt rotor research aircraftFor the past 20 years, a significant effort has been made to understand and predict the structural aeroelastic stability characteristics of the tilt rotor concept. Beginning with the rotor-pylon oscillation of the XV-3 aircraft, the problem was identified and then subjected to a series of…20 ppNASA-TM-84293
- Dynamic Wind-Tunnel Testing of a Sub-Scale Iced Business JetThe effect of ice accretion on a 1/12-scale complete aircraft model of a business jet was studied in a rotary-balance wind tunnel. Three types of ice accretions were considered: ice protection system failure shape, pre-activation roughness, and runback shapes that form downstream of the thermal ice…21 ppNASA/TM-2006-214268
- Dynamic Wind-Tunnel Testing of a Sub-Scale Iced S-3B VikingThe effect of ice accretion on a 1/12-scale complete aircraft model of S-3B Viking was studied in a rotary-balance wind tunnel. Two types of ice accretions were considered: ice protection system failure shape and runback shapes that form downstream of the thermal ice protection system. The results…20 pp20120014283
- Dynamics and Adaptive Control for Stability Recovery of Damaged AircraftThis paper presents a recent study of a damaged generic transport model as part of a NASA research project to investigate adaptive control methods for stability recovery of damaged aircraft operating in off-nominal flight conditions under damage and or failures. Aerodynamic modeling of damage…23 pp
- Economic evaluation of flying-qualities design criteria for a transport configured with relaxed static stabilityDirect constrained parameter optimization was used to optimally size a medium range transport for minimum direct operating cost. Several stability and control constraints were varied to study the sensitivity of the configuration to specifying the unaugmented flying qualities of transports designed…31 pp19810005457
- Effect of aeroelastic-propulsive interactions on flight dynamics of a hypersonic vehicleThe desire to achieve orbit-on-demand access to space with rapid turn-around capability and aircraft-like processing operations has given rise to numerous hypersonic aerospace plane design concepts which would take off horizontally from a conventional runway and employ air-breathing scramjet…22 pp19940020631
- Effect of Compressibility on Pressure Distribution over an Airfoil with a Slotted Frise AileronPressure distribution measurements were made over an airfoil with slotted Frise aileron up to 0.76 Mach at various angles of attack and aileron defections. Section characteristics were determined from these pressure data. Results indicated loss of aileron rolling power for deflections ranging from…68 ppNACA-ACR-L4G12
- Effect of Compressibility on the Pressure and Forces Acting on a Modified NACA 65,3-019 Airfoil Having A 0.20-Chord FlapAn investigation has been conducted in the Langley rectangular high-speed tunnel to determine the effect of compressibility on the pressure distribution for a modified NACA 65,3-019 airfoil having a 0.20-chord flap. The investigation was made for an angle-of-attack range extending from -2 to 12 deg…82 ppNACA-WR-L-76
- Effect of Control System Augmentation on Handling Qualities and Task Performance in Good and Degraded Visual EnvironmentsIn June 2013, NASA and the U.S. Army jointly conducted a simulation experiment in the NASA-Ames Vertical Motion Simulator that examined and quantified the effects of limited-authority control system augmentation on handling qualities and task performance in both good and degraded visual…30 pp20180008501
- Effect of Full-Chord Porosity on Aerodynamic Characteristics of the NACA 0012 AirfoilA test was conducted on a model of the NACA 0012 airfoil section with a solid upper surface or a porous upper surface with a cavity beneath for passive venting. The purposes of the test were to investigate the aerodynamic characteristics of an airfoil with full-chord porosity and to assess the…96 ppNASA-TP-3591
- Effect of Geometric Granularity on the Noise Signature of a Full-Scale Large Civil Transport Nose Landing GearResults from a comprehensive simulation campaign focused on characterizing the air-frame noise signature of a full-scale Boeing 777-300ER nose landing gear are presented. The as-flown, installed nose gear geometry was used to assess how accurately the selected computational methodology can predict…16 pp
- Effect of interaction on landing-gear behavior and dynamic loads in a flexible airplane structureThe effects of interaction between a landing gear and a flexible airplane structure on the behavior of the landing gear and the loads in the structure have been studied by treating the equations of motion of the airplane and the landing gear as a coupled system. The landing gear is considered to…30 ppNACA-TR-1278
- Effect of protective coatings on the stress- corrosion properties of supersonic-transport skin materials eleventh quarterly status report, 1 jun. - 31 aug. 1965Protective coatings effect on stress corrosion properties of supersonic transport skin materials34 ppNASA-CR-67014
- Effect of protective coatings on the stress- corrosion properties of supersonic-transport skin materials tenth quarterly status report, 1 mar. - 31 may 1965Protective coating effect on stress corrosion properties of supersonic transport skin materials - bending-ductility evaluation27 ppNASA-CR-63784
- Effect of sampling rate and record length on the determination of stability and control derivativesFlight data from five aircraft were used to assess the effects of sampling rate and record length reductions on estimates of stability and control derivatives produced by a maximum likelihood estimation method. Derivatives could be extracted from flight data with the maximum likelihood estimation…139 ppNASA-TM-72858
- Effect of stabilization on VTOL aircraft in hovering flightA motion simulator study was conducted to determine the effects of roll and pitch stabilization on the handling qualities and control power requirements of VTOL aircraft during hover and short-distance maneuvering flight. Three levels of stabilization complexity were compared: (1) no stabilization,…27 pp19720020365
- Effect of wing planform modification on longitudinal characteristics of a variable- sweep m wingWind tunnel testing to determine effects of wing planform modifications on longitudinal aerodynamic characteristics of variable-sweep M planform wing28 pp19650024621
- Effectiveness of Thermal-Pneumatic Airfoil-Ice-Protection SystemIcing and drag investigations were conducted in the NACA Lewis icing research tunnel employing a combination thermal-pneumatic de-icer mounted on a 42-inch-chord NACA 0018 airfoil. The de-icer consisted of a 3-inch-wide electrically heated strip symmetrically located about the leading edge with…16 ppNACA-RM-E50K10A
- Effects of a simple stability augmentation system on the performance of non-instrument- qualified light-aircraft pilots during instrument flightSimple stability instrumentation and pilot performance for light aircraft safety during instrumented flight27 pp19670016467
- Effects of aircraft noise on flight and ground structuresAcoustic loads measured on jet-powered STOL configurations are presented for externally blown and upper surface blown flap models ranging in size from a small laboratory model up to a full-scale aircraft model. The implications of the measured loads for potential acoustic fatigue and cabin noise…13 pp19770011165
- Effects of airfoil shape, thickness, camber, and angle of attack on calculated transonic unsteady airloadsThe effects of airfoil shape, thickness, camber, and mean angle of attack on transonic unsteady airloads were investigated as calculated by the transonic small-disturbance computer code XTRAN2L. Shape effects were investigated by examining the pressure distributions, shock locations, and unsteady…55 ppNASA-TM-86320
- Effects of asymmetry on the dynamic stability of aircraftThe oblique wing concept for transonic aircraft was proposed to reduce drag. The dynamic stability of the aircraft was investigated by analytically determining the stability derivatives at angles of skew ranging from 0 and 45 deg and using these stability derivatives in a linear analysis of the…260 ppNASA-CR-142857
- Effects of cockpit lateral stick characteristics on handling qualities and pilot dynamicsThis report presents the results of analysis of cockpit lateral control feel-system studies. Variations in feel-system natural frequency, damping, and command sensing reference (force and position) were investigated, in combination with variations in the aircraft response characteristics. The…208 pp19920019341
- Effects of Commercially Available Protective Coatings on Stress-corrosion Properties of Supersonic-transport Skin Materials Final Summary Report, 1 Jun. 1964 - 31 Jan. 1966Protective coating effect on stress corrosion properties of supersonic transport skin materials129 ppNASA-CR-74414
- Effects of Compressibility on the Maximum Lift Characteristics and Spanwise Load Distribution of a 12-Foot-Span Fighter-Type Wing of NACA 230-Series Airfoil SectionsLift characteristics and pressure distribution for a NACA 230 wing were investigated for an angle of attack range of from -10 to +24 degrees and Mach range of from 0.2 to 0.7. Maximum lift coefficient increased up to a Mach number of 0.3, decreased rapidly to a Mach number of 0.55, and then…29 ppNACA-ACR-L5G10
- Effects of control laws and relaxed static stability on vertical ride quality of flexible aircraftState variable techniques are utilized to generate the RMS vertical load factors for the B-52H and B-1 bombers at low level, mission critical, cruise conditions. A ride quality index is proposed to provide meaningful comparisons between different controls or conditions. Ride quality is shown to be…110 ppNASA-CR-143843
- Effects of Coupling Between Pitch and Roll Control Inputs on the Handling Qualities of VTOL AircraftEffects of coupling between pitch and roll control inputs on handling qualities of vtol aircraft14 ppNASA-TN-D-1233
- Effects of dynamic aeroelasticity on handling qualities and pilot ratingPilot performance parameters, such as pilot ratings, tracking errors, and pilot comments were determined for a longitudinal pitch tracking task using a large, flexible bomber with parametric variations in the undamped natural frequencies of the two lowest frequency symmetric elastic modes. This…121 pp19780005127
- Effects of forward contour modification on the aerodynamic characteristics of the NACA 641-212 airfoil sectionTwo different forward contour modifications designed to increase the maximum lift coefficient of the NACA 64 sub 1-212 airfoil section were evaluated experimentally at low speeds. One modification consisted of a slight droop of the leading edge with an increased leading-edge radius; the other…84 ppNASA-TM-X-3293
- Effects of Gas Turbine Component Performance on Engine and Rotary Wing Vehicle Size and PerformanceIn support of the Fundamental Aeronautics Program, Subsonic Rotary Wing Project, further gas turbine engine studies have been performed to quantify the effects of advanced gas turbine technologies on engine weight and fuel efficiency and the subsequent effects on a civilian rotary wing vehicle size…18 pp20100042404
- Effects of Gyroscopic Cross Coupling between Pitch and Roll on the Handling Qualities of VTOL AircraftIn order to provide information relative to the effects of gyroscopic cross coupling between pitch and roll on the handling qualities of VTOL aircraft, a flight investigation has been conducted during which cross coupling was simulated. Generality is achieved by presenting the results of the flight…21 pp20040008096
- Effects of independent variation of Mach and Reynolds numbers on the low-speed aerodynamic characteristics of the NACA 0012 airfoil sectionA comprehensive data base is given for the low speed aerodynamic characteristics of the NACA 0012 airfoil section. The Langley low-turbulence pressure tunnel is the facility used to obtain the data. Included in the report are the effects of Mach number and Reynolds number and transition fixing on…97 ppNASA-TM-4074
- Effects of Induction-System Icing on Aircraft-Engine Operating CharacteristicsAn investigation was conducted on a multicylinder aircraft engine on a dynamometer stand to determine the effect of induction-system icing on engine operating characteristics and to compare the results with those of a previous laboratory investigation in which only the carburetor and the…19 ppNACA-RM-E6L24
- Effects of landing gear, speed brake and protuberances on the longitudinal aerodynamic characteristics of an NASA supercritical-wing research airplane modelAn investigation was conducted in the Langley Research Center 8-foot transonic pressure tunnel to determine the effects of the landing gear, speed brake and the major airplane protuberances on the longitudinal aerodynamic characteristics of an 0.087-scale model of the TF-8A supercritical-wing…57 pp19830002815
- Effects of lateral control characteristics on hovering a jet lift vtol aircraftEffect of lateral control characteristics on hovering of jet lift VTOL aircraft15 ppNASA-TN-D-2701
- Effects of nacelle shape on drag and weight of a supersonic cruising aircraftThe quantitive relationship of cruise drag and nacelle shape was investigated for a representative advanced supersonic transport configuration. Nacelle shape parameters were systematically varied, and the effects of these variations on wave and friction drag were determined. The effects of changes…102 pp19760005981
- Effects of nonlinear aerodynamics and static aeroelasticity on mission performance calculations for a fighter aircraftDuring conceptual design studies of advanced aircraft, the usual practice is to use linear theory to calculate the aerodynamic characteristics of candidate rigid (nonflexible) geometric external shapes. Recent developments and improvements in computational methods, especially computational fluid…20 pp19890015799
- Effects of periodic blowing through flush transverse slots on turbulent boundary layer skin frictionEffects of periodic blowing through flush transverse slots on turbulent boundary layer skin friction69 pp19660029514
- Effects of Propellers and of Vibration on the Extent of Laminar Flow on the NACA 27-212 Airfoil11 ppNACA-WR-L-784
- Effects of rotor parameter variations on handling qualities of unaugmented helicopters in simulated terrain flightA coordinated analysis and ground simulator experiment was performed to investigate the effects on single rotor helicopter handling qualities of systematic variations in the main rotor hinge restraint, hub hinge offset, pitch-flap coupling, and blade lock number. Teetering rotor, articulated rotor,…88 pp19800022901
- Effects of side-stick controllers on rotorcraft handling qualities for terrain flightPertinent fixed and rotary-wing feasibility studies and handling-qualities research programs are reviewed and the effects of certain controller characteristics on handling qualities for specific rotorcraft flight tasks are summarized. The effects of the controller force-deflection relationship and…15 pp19850016956
- Effects of Simulated Rocket-jet Exhaust on Stability and Control of a Research-type Airplane Configuration at a Mach Number of 6.86Simulated rocket jet exhaust effect on stability and control of research aircraft configuration36 ppNASA-TM-X-127
- Effects of simulated turbulence on aircraft handling qualitiesThe influence of simulated turbulence on aircraft handling qualities is presented. Pilot opinions of the handling qualities of a light general aviation aircraft were evaluated in a motion-base simulator using a simulated turbulence environment. A realistic representation of turbulence disturbances…102 pp19770013171
- Effects of wing dihedral and planform on sta- bility characteristics of a research model at mach numbers from 1.80 to 4.63Effects of wing dihedral and planform on stability characteristics of aircraft model - wind tunnel testing61 ppNASA-TN-D-2914
- Effects of wing height on the stability and control characteristics at a mach number of 2.01 of a canard airplane configuration with a 70 deg delta wingWing height effect on stability and control of 70 deg delta-wing canard-aircraft configuration at Mach 2.0131 ppNASA-TM-X-328
- Effects of wing lift and weight on landing-gear loadsThe effects of wing lift and weight on maximum landing gear loads were investigated by drop testing a small landing gear with oleo shock strut in the Langley impact basin. Lift forces were mechanically applied to the dropping mass to produce wing lift factors between 1000 and 2500 pounds. The…43 ppNACA-TN-2645
- EFFECTS OF WING VERTICAL LOCATION ON THE STABILITY AND CONTROL CHARACTERISTICS AT A MACH NUMBER OF 2.01 OF A CANARD AIRPLANE CONFIGURATION WITH A TRAPEZOIDAL ASPECT-RATIO-3 WINGEffects of wing vertical location on stability and control of canard aircraft at supersonic speeds36 ppNASA-TM-X-44
- Efficient Variable-Pitch Propeller Aerodynamic Model Development for Vectored-Thrust eVTOL AircraftThis paper describes a variable-pitch propeller testing and aerodynamic modeling methodology for electric vertical takeoff and landing (eVTOL) aircraft using wind tunnel testing. Propellers used for eVTOL aircraft propulsion systems experience a wide range of operating conditions resulting in…31 pp
- Efficient, Low-Cost Fan System Research for General Aviation and Commuter AircraftThis document reports research investigations into efficient, low-cost fan system concepts for high bypass turbofans for future general aviation and commuter aircraft. The research specifically addressed lower pressure ratio fans for good propulsive efficiencies in the 200 to 400 knot flight speed…80 pp20030067980
- EGADS: A microcomputer program for estimating the aerodynamic performance of general aviation aircraftEGADS is a comprehensive preliminary design tool for estimating the performance of light, single-engine general aviation aircraft. The software runs on the Apple Macintosh series of personal computers and assists amateur designers and aeronautical engineering students in performing the many…59 pp19940021588
- Eigensystem synthesis for active flutter suppression on an oblique-wing aircraftThe application of the eigensystem synthesis technique to place the closed-loop eigenvalues and shape the closed-loop eigenvectors has not been practical for active flutter suppression, primarily because of the availability of only one control surface (aileron) for flutter suppression. The…10 pp19860020396
- Electrical Power System Sizing Within the Numerical Propulsion System SimulationElectrified aircraft propulsion seeks to address ambitious goals in the commercial airline industry, including significant decreases in fuel burn, emissions, noise, and takeoff field length. In order to move these electrified propulsion concepts forward, analysis tools are needed that can model…8 pp20190029592
- Electrified Aircraft Propulsion (EAP) Educational BriefingThis is an educational briefing package for Electrified Aircraft Propulsion and Power (EAPP); this presentation will brief on NASA needs and challenges in Electrified Aircraft Propulsion and Power as well as the SBIR program and proposal guidance.51 pp20190004971
- Electrified Aircraft Propulsion DevelopmentThe benefits of electrified aircraft propulsion improves aircrafts like single aisle transports, enables new configurations of vertical take-off landing aircrafts and revitalizes the economic case for small short-range aircraft services. Future strategies and markets for supersonic and commercial…23 pp20180006992
- Electro-impulse de-icing testing analysis and designElectro-Impulse De-Icing (EIDI) is a method of ice removal by sharp blows delivered by a transient electromagnetic field. Detailed results are given for studies of the electrodynamic phenomena. Structural dynamic tests and computations are described. Also reported are ten sets of tests at NASA's…358 pp19900000715
- Embedded Wing Propulsion Conceptual StudyAs a part of distributed propulsion work under NASA's Revolutionary Aeropropulsion Concepts or RAC project, a new propulsion-airframe integrated vehicle concept called Embedded Wing Propulsion (EWP) is developed and examined through system and computational fluid dynamics (CFD) studies. The idea…17 pp20030112863
- Emergency Control Aircraft System Using Thrust ModulationA digital longitudinal Aircraft Propulsion Control (APC system of a multiengine aircraft is provided by engine thrust modulation in response to comparing an input flightpath angle signal (gamma)c from a pilot thumbwheel. or an ILS system with a sensed flightpath angle y to produce an error signal…8 ppPatent Number: US-Patent-6,041,273
- Emergency in-flight egress opening for general aviation aircraftAn emergency in-flight egress system was installed in a light general aviation airplane. The airplane had no provision for egress on the left side. To avoid a major structural redesign for a mechanical door, an add on 11.2 kg (24.6 lb) pyrotechnic-actuated system was developed to create an opening…22 pp19800015020
- Emergency in-flight egress opening for general aviation aircraftIn support of a stall/spin research program, an emergency in-flight egress system is being installed in a light general aviation airplane. To avoid a major structural redesign for a mechanical door, an add-on 11.2 kg pyrotechnic-actuated system was developed to create an opening in the existing…32 pp19800012808
- Emergency Multiengine Aircraft System for Lateral Control Using Differential Thrust Control of Wing EnginesDevelopment of an emergency flight control system is disclosed for lateral control using only differential engine thrust modulation of multiengine aircraft is currently underway. The multiengine has at least two engines laterally displaced to the left and right from the axis of the aircraft. In…6 ppPatent Number: NASA-Case-DRC-097021
- Empirical Prediction of Aircraft Landing Gear NoiseThis report documents a semi-empirical/semi-analytical method for landing gear noise prediction. The method is based on scaling laws of the theory of aerodynamic noise generation and correlation of these scaling laws with current available test data. The former gives the method a sound theoretical…38 ppNASA/CR-2005-213780
- Enabling Advanced Wind-Tunnel Research Methods Using the NASA Langley 12-Foot Low Speed TunnelDesign of Experiment (DOE) testing methods were used to gather wind tunnel data characterizing the aerodynamic and propulsion forces and moments acting on a complex vehicle configuration with 10 motor-driven propellers, 9 control surfaces, a tilt wing, and a tilt tail. This paper describes the…22 ppAIAA Paper-2014-3000
- Enabling Electric Propulsion for FlightDescription of current ARMD projects; Team Seedling project AFRC and LaRC 31ft distributed electric propulsion wing on truck bed up 75 miles per hour for coefficient of lift validation. Convergent Aeronautic Solutions project (new ARMD reorg), sub-project Convergent Electric Propulsion Technologies…32 pp20140017743
- Enabling Electric Propulsion for FlightTeam Seedling project AFRC and LaRC 31ft distributed electric propulsion wing on truck bed up 75 miles per hour for coefficient of lift validation. Convergent Aeronautic Solutions project, sub-project Convergent Electric Propulsion Technologies AFRC, LaRC and GRC, re-winging a 4 passenger Tecnam…16 pp20150009298
- Enabling Electric Propulsion for Flight - Hybrid Electric Aircraft Research at AFRCAdvances in electric machine efficiency and energy storage capability are enabling a new alternative to traditional propulsion systems for aircraft. This has already begun with several small concept and demonstration vehicles, and NASA projects this technology will be essential to meet energy and…15 pp20140010471
- Energy efficient engine flight propulsion system: Aircraft/engine integration evaluationResults of aircraft/engine integration studies conducted on an advanced flight propulsion system are reported. Economic evaluations of the preliminary design are included and indicate that program goals will be met. Installed sfc, DOC, noise, and emissions were evaluated. Aircraft installation…312 pp19810013521
- Energy efficient engine high-pressure turbine component rig performance test reportA rig test of the cooled high-pressure turbine component for the Energy Efficient Engine was successfully completed. The principal objective of this test was to substantiate the turbine design point performance as well as determine off-design performance with the interaction of the secondary flow…247 pp19850021643
- Energy efficient engine high-pressure turbine detailed design reportThe energy efficient engine high-pressure turbine is a single stage system based on technology advancements in the areas of aerodynamics, structures and materials to achieve high performance, low operating economics and durability commensurate with commercial service requirements. Low loss…178 pp19840020719
- Energy efficient engine high-pressure turbine supersonic cascade technology reportThe performance of two vane endwall geometries and three blade sections for the high-pressure turbine was evaluated in terms of the efficiency requirements of the Energy Efficient Engine high-pressure turbine component. The van endwall designs featured a straight wall and S-wall configuration. The…149 pp19840019671
- Energy efficient engine program contributions to aircraft fuel conservationSignificant advances in high bypass turbofan technologies that enhance fuel efficiency have been demonstrated in the NASA Energy Efficient Engine Program. This highly successful second propulsion element of the NASA Aircraft Energy Efficiency Program included major contract efforts with both…28 pp19840021807
- Energy efficient engine: High pressure turbine uncooled rig technology reportResults obtained from testing five performance builds (three vane cascades and two rotating rigs of the Energy Efficient Engine uncooled rig have established the uncooled aerodynamic efficiency of the high-pressure turbine at 91.1 percent. This efficiency level was attained by increasing the rim…247 pp19820024507
- Energy efficient engine: Propulsion system-aircraft integration evaluationFlight performance and operating economics of future commercial transports utilizing the energy efficient engine were assessed as well as the probability of meeting NASA's goals for TSFC, DOC, noise, and emissions. Results of the initial propulsion systems aircraft integration evaluation presented…309 pp19790008679
- Energy efficient engine: Turbine intermediate case and low-pressure turbine component test hardware detailed design reportA four stage, low pressure turbine component has been designed to power the fan and low pressure compressor system in the Energy Efficient Engine. Designs for a turbine intermediate case and an exit guide vane assembly also have been established. The components incorporate numerous technology…302 pp19840020720
- Engine Company Evaluation of Feasibility of Aircraft Retrofit Water-Injected TurbomachinesThis study supports the NASA Glenn Research Center and the U.S. Air Force Research Laboratory in their efforts to evaluate the effect of water injection on aircraft engine performance and emissions. In this study, water is only injected during the takeoff and initial climb phase of a flight. There…35 pp20060012147
- Engine Yaw Augmentation for Hybrid-Wing-Body Aircraft via Optimal Control Allocation TechniquesAsymmetric engine thrust was implemented in a hybrid-wing-body non-linear simulation to reduce the amount of aerodynamic surface deflection required for yaw stability and control. Hybrid-wing-body aircraft are especially susceptible to yaw surface deflection due to their decreased bare airframe yaw…21 ppDFRC-E-DAA-TN3895
- Enhanced Engine Control for Emergency OperationC-MAPSS40k engine simulation has been developed and is available to the public. The authenticity of the engine performance and controller enabled the development of realistic enhanced control modes through controller modification alone. Use of enhanced control modes improved stability and control…35 ppE-18526
- Enhanced Fan Noise Modeling for Turbofan EnginesThis report describes work by consultants to Diversitech Inc. for the NASA Glenn Research Center (GRC) to revise the fan noise prediction procedure based on fan noise data obtained in the 9- by 15 Foot Low-Speed Wind Tunnel at GRC. The purpose of this task is to begin development of an enhanced,…92 pp20150000884
- Enhancing Flight Test Safety with Real-Time Early Warning TechniquesContemporary approaches to aerospace vehicle system monitoring rely heavily on thresholds that represent a compromise between providing warning early enough to avert a mishap while simultaneously minimizing false alarms. While this reliance on thresholds has been in place for decades and has…29 pp20190000256
- Environmentally Friendly Rotorcraft Concepts: 2011-2014: US/France MoA Helicopter Aeromechanics - Task 5Motivation: Greenhouse gas concentrations have increased well beyond their pre-industrial levels due to human activities; Aircraft emissions are becoming regulated in industrialized nations, so future rotorcraft will need to be designed for minimal environmental impact. Objectives: Determine…24 pp20180008748
- Estimated aerodynamics of all-body hypersonic aircraft configurationsEstimated aerodynamics of all-body hypersonic aircraft configurations39 pp19710010231
- Estimated Flying Qualities of the Martin Model 202 AirplaneThe flying qualities of the Martin model 202 airplane have been estimated chiefly from the results of tests of an 0.0875-scale complete model with power made in the Wright Brothers tunnel at the Massachusetts Institute of Technology and from partial span wing and isolated vertical tail tests made…48 pp20050019466
- Estimation of Aircraft Unsteady Aerodynamic Parameters from Dynamic Wind Tunnel TestingImproved aerodynamic mathematical models, for use in aircraft simulation or flight control design, are required when representing nonlinear unsteady aerodynamics. A key limitation of conventional aerodynamic models is the inability to map frequency and amplitude dependent data into the equations of…9 pp20010098300
- Estimation of Handling Qualities Parameters of the Tu-144 Supersonic Transport Aircraft from Flight Test DataLow order equivalent system (LOES) models for the Tu-144 supersonic transport aircraft were identified from flight test data. The mathematical models were given in terms of transfer functions with a time delay by the military standard MIL-STD-1797A, "Flying Qualities of Piloted Aircraft," and the…120 pp20000103558
- Estimation of longitudinal stability and control derivatives for an icing research aircraft from flight dataThe results of applying a modified stepwise regression algorithm and a maximum likelihood algorithm to flight data from a twin-engine commuter-class icing research aircraft are presented. The results are in the form of body-axis stability and control derivatives related to the short-period,…24 ppNASA-TM-4099
- Estimation of Longitudinal Unsteady Aerodynamics of a Wing-Tail Combination From Wind Tunnel DataThis paper presents an initial step toward model identification from wind tunnel data for an airliner configuration. Two approaches to modeling a transport configuration are considered and applied to both steady and large-amplitude forced-oscillation wind tunnel data taken over a wide range of…13 pp20060047570
- Estimation of Unsteady Aerodynamic Models from Dynamic Wind Tunnel DataDemanding aerodynamic modelling requirements for military and civilian aircraft have motivated researchers to improve computational and experimental techniques and to pursue closer collaboration in these areas. Model identification and validation techniques are key components for this research.…23 pp20110016506
- Evaluation and Analysis of F-16XL Wind Tunnel Data from Dynamic TestsA series of wind tunnel tests were conducted in the NASA Langley Research Center as part of an ongoing effort to develop and test mathematical models for aircraft rigid-body aerodynamics in nonlinear unsteady flight regimes. Analysis of measurement accuracy, especially for nonlinear dynamic systems…11 pp20040085728
- Evaluation of a wind-tunnel gust response technique including correlations with analytical and flight test resultsA wind tunnel technique for obtaining gust frequency response functions for use in predicting the response of flexible aircraft to atmospheric turbulence is evaluated. The tunnel test results for a dynamically scaled cable supported aeroelastic model are compared with analytical and flight data.…52 ppNASA-TP-1501
- Evaluation of active control technology for short haul aircraftAn evaluation of the economics of short-haul aircraft designed with active controls technology and low wing-loading to achieve short field performance with good ride quality is presented. Results indicate that for such a system incorporating gust load alleviation and augmented stability the direct…156 ppNASA-CR-137634
- Evaluation of advanced lift concepts and fuel conservative short-haul aircraft, volume 1The performance and economics of a twin-engine augmentor wing airplane were evaluated in two phases. Design aspects of the over-the-wing/internally blown flap hybrid, augmentor wing, and mechanical flap aircraft were investigated for 910 m. field length with parametric extension to other field…312 pp19750012219
- Evaluation of advanced lift concepts and potential fuel conservation for short-haul aircraftThe effect of different field lengths, cruise requirements, noise level, and engine cycle characteristics on minimizing fuel consumption and minimizing operating cost at high fuel prices were evaluated for some advanced short-haul aircraft. The conceptual aircraft were designed for 148 passengers…95 pp19750008485
- Evaluation of Alternative Altitude Scaling Methods for Thermal Ice Protection System in NASA Icing Research TunnelA test was conducted at NASA Icing Research Tunnel to evaluate altitude scaling methods for thermal ice protection system. Two scaling methods based on Weber number were compared against a method based on the Reynolds number. The results generally agreed with the previous set of tests conducted in…24 pp20170007301
- Evaluation of Alternative Altitude Scaling Methods for Thermal Ice Protection System in NASA Icing Research TunnelA test was conducted at NASA Icing Research Tunnel to evaluate altitude scaling methods for thermal ice protection system. Two new scaling methods based on Weber number were compared against a method based on Reynolds number. The results generally agreed with the previous set of tests conducted in…23 ppGRC-E-DAA-TN42129
- Evaluation of Electrical System Requirements for Implementing Turbine Electrified Energy ManagementTurbine Electrified Energy Management (TEEM) is a concept concerned with the management of energy in an electrified propulsion system. The management of energy in the hybrid-electric architecture has potential to benefit the turbomachinery and the aircraft it powers. The concept is particularly…19 pp20190030360
- Evaluation of Flying Qualities and Guidance Displays for an Advanced Tilt-Wing STOL Transport Aircraft in Final Approach and LandingA piloted simulation was performed on the Vertical Motion Simulator at NASA Ames Research Center to evaluate flying qualities of a tilt-wing Short Take-Off and Landing (STOL) transport aircraft during final approach and landing. The experiment was conducted to assess the design s handling…9 pp20030071140
- Evaluation of High-Angle-of-Attack Handling Qualities for the X-31A Using Standard Evaluation ManeuversThe X-31A aircraft gross-acquisition and fine-tracking handling qualities have been evaluated using standard evaluation maneuvers developed by Wright Laboratory, Wright-Patterson Air Force Base. The emphasis of the testing is in the angle-of-attack range between 30 deg and 70 deg. Longitudinal…36 pp19970004646
- Evaluation of High-Speed Civil Transport Handling Qualities Criteria with Supersonic Flight DataMost flying qualities criteria have been developed from data in the subsonic flight regime. Unique characteristics of supersonic flight raise questions about whether these criteria successfully extend into the supersonic flight regime. Approximately 25 years ago NASA Dryden Flight Research Center…30 pp19970014738
- Evaluation of Icing Scaling on Swept NACA 0012 Airfoil ModelsIcing scaling tests in the NASA Glenn Icing Research Tunnel (IRT) were performed on swept wing models using existing recommended scaling methods that were originally developed for straight wing. Some needed modifications on the stagnation-point local collection efficiency (i.e., beta(sub 0)…22 ppNASA/CR-2012-217419
- Evaluation of laminar flow control systems concepts for subsonic commercial transport aircraftAn evaluation was made of laminar flow control (LFC) system concepts for subsonic commercial transport aircraft. Configuration design studies, performance analyses, fabrication development, structural testing, wind tunnel testing, and contamination-avoidance techniques were included. As a result of…513 pp19860018605
- Evaluation of laminar flow control systems for subsonic commercial transport aircraft: Executive summaryAn evaluation was made of laminar flow control (LFC) system concepts for subsonic commercial transport aircraft. Configuration design studies, performance analyses, fabrication development, structural testing, wind tunnel testing, and contamination-avoidance techniques were included. As a result of…77 ppNASA-CR-159252
- Evaluation of propfan propulsion applied to general aviationPropfan propulsion on business aircraft was evaluated. Comparisons, in terms of cost and performance, were made between propfan propulsion systems and conventional turbofan propulsion systems on a typical business aircraft. In addition, configuration and cost sensitivity studies were conducted to…140 pp19860015224
- Evaluation of Response Surface Experiment Designs for Distributed Propulsion Aircraft Aero-Propulsive ModelingModern distributed hybrid and electric propulsion aircraft, including vertical, short, and conventional takeoff and landing configurations, exhibit significant aero-propulsive complexity and a large number of interacting test factors. This paper presents the development and evaluation of experiment…23 pp
- Evaluation of the gust-alleviation characteristics and handling qualities of a free-wing aircraftDynamic characteristics of aircraft with wings free to pivot spanwise axis154 pp19700014919
- Evaluation of viscous drag reduction schemes for subsonic transportsThe results are described of a theoretical study of viscous drag reduction schemes for potential application to the fuselage of a long-haul subsonic transport aircraft. The schemes which were examined included tangential slot injection on the fuselage and various synergetic combinations of…114 pp19760005925
- eVTOL Vehicle-Agnostic Instrument Flight Procedures Test PlanNASA Advanced Air Mobility National Campaign is researching the utility of electric vertical takeoff and land (eVTOL) advanced air mobility (AAM) instrument flight procedures. The result will be dynamic and tailored procedures that align to the following modus operandi: maximize safety,…62 pp
- Examination of Icing Induced Loss of Control and Its MitigationsFactors external to the aircraft are often a significant causal factor in loss of control (LOC) accidents. In today s aviation world, very few accidents stem from a single cause and typically have a number of causal factors that culminate in a LOC accident. Very often the "trigger" that initiates…17 pp20100042407
- Exit Boundary Layer Data for a Round Convergent Nozzle in Support of Numerical Simulation EffortsAn experiment is conducted with hot-wire anemometry to document the exit boundary layer characteristics of two nozzle configurations at jet Mach numbers up to 0.82. Far-field noise and jet plume experimental data from these two configurations have been used in Large Eddy Simulations (LES) of jets…22 pp20190027560
- Experience with synchronous and asynchronous digital control systemsFlight control systems have undergone a revolution since the days of simple mechanical linkages; presently the most advanced systems are full-authority, full-time digital systems controlling unstable aircraft. With the use of advanced control systems, the aerodynamic design can incorporate features…20 ppNASA-TM-88271
- Experiences with the design and implementation of flutter suppression systemsResearch efforts aim at flutter suppression are discussed. The application of active controls technology to reduce the aeroelastic response of aircraft structures is discussed. Feedback control, control law design processes and synthesis, wind tunnel studies, and delta-wing wind tunnel models are…20 pp19840012525
- Experimental and analytical determination of characteristics affecting light aircraft landing-gear dynamicsAn experimental and analytical investigation was conducted to determine which characteristics of a light aircraft landing gear influence gear dynamic behavior significantly. The investigation focused particularly on possible modification for load control. Pseudostatic tests were conducted to…47 ppNASA-TM-X-3561
- Experimental and calculated characteristics of three wings of NACA 64-210 and 65-210 airfoil sections with and without 2 degree washoutReport presents the results of an investigation conducted to determine some of the effects of airfoil section and washout on the experimental and calculated characteristics of 10-percent-thick wings. Three wings of aspect ratio 9 and ratio of root chord to tip chord 2.5 were tested. One wing had…18 ppNACA-TN-1422
- Experimental and Theoretical Investigation of Wind Tunnel Geometry, Emphasizing Factors Pertinent to V/STOL Vehicles Testing Progress Report No. 3, Sep. 16, 1965 - Mar. 15, 1966Wind tunnel tests to measure converging flow field effects on V/STOL models5 pp19660020004
- Experimental and theoretical low speed aerodynamic characteristics of the NACA 65 sub 1-213, alpha equals 0.50, airfoilLow-speed wind-tunnel tests have been conducted to determine the two-dimensional aerodynamic characteristics of the NACA 65 sub 1-213, a = 0.05, airfoil. The results were compared with data from another low-speed wind tunnel and also with theoretical predictions obtained by using a viscous subsonic…76 ppNASA-TM-X-3160
- Experimental atmospheric absorption values from aircraft flyover noise signalsAnalysis of aircraft noise recordings to determine experimental values of atmospheric sound absorption75 pp19710019407
- Experimental Investigation of a 4.54-inch- Mean-diameter Three-stage Reverse-flow Reentry TurbineThree-stage reverse flow reentry turbine engine27 pp19640000275
- Experimental Investigation of a Preloaded Spring-tab Flutter ModelAn experimental investigation was made of a preloaded spring-tab flutter model to determine the effects on flutter speed of aspect ratio, tab frequency, and preloaded spring constant. The rudder was mass-balanced, and the flutter mode studied was essentially one of three degrees of freedom (fin…35 pp19930085801
- Experimental investigation of active loads control for aircraft landing gearAircraft dynamic loads and vibrations resulting from landing impact and from runway and taxiway unevenness are recognized as significant in causing fatigue damage, dynamic stress on the airframe, crew and passenger discomfort, and reduction of the pilot's ability to control the aircraft during…72 ppNASA-TP-2042
- Experimental Investigation of Convoluted Contouring for Aircraft Afterbody Drag ReductionAn experimental investigation was performed in the NASA Langley 16-Foot Transonic Tunnel to determine the aerodynamic effects of external convolutions, placed on the boattail of a nonaxisymmetric nozzle for drag reduction. Boattail angles of 15 and 22 were tested with convolutions placed at a…11 pp20040086835
- Experimental Results from the Active Aeroelastic Wing Wind Tunnel Test ProgramThe Active Aeroelastic Wing (AAW) program is a cooperative effort among NASA, the Air Force Research Laboratory and the Boeing Company, encompassing flight testing, wind tunnel testing and analyses. The objective of the AAW program is to investigate the improvements that can be realized by…16 ppAIAA Paper 2005-2234
- Experimental Studies of Flow Separation of the NACA 2412 Airfoil at Low SpeedsWind tunnel tests have been conducted on an NACA 2412 airfoil section at Reynolds number of 2.2 x 10(exp 6) and Mach number of 0.13. Detailed measurements of flow fields associated with turbulent boundary layers have been obtained at angles of attack of 12.4 degrees, 14.4 degrees, and 16.4 degrees.…72 ppNASA-CR-197497
- Experimental study of fluid deicing system in the NASA Icing Research TunnelAn investigation of the icing of horizontal control surfaces at the VFW in 1970 led them to select the NASA Icing Research Tunnel at LRC for their tests. Tests were performed for the VFW 614 aircraft. The TKS ice warning system, the Rosemont ice warning system and the liquid water content indicator…153 pp19840008152
- Experimental Study of Noise Shielding by a NACA 0012 AirfoilThe effects of sound source location, Mach number and angle of attack on the shielding of a laser-induced sound source by a NACA 0012 airfoil are examined. The sound source is a small plasma generated by a high energy, laser beam focused to a point. In-flow microphone measurements are acquired in…18 ppNF1676L-28551
- Experimental Study of Turbine Fuel Thermal Stability in an Aircraft Fuel System SimulatorThe thermal stability of aircraft gas turbines fuels was investigated. The objectives were: (1) to design and build an aircraft fuel system simulator; (2) to establish criteria for quantitative assessment of fuel thermal degradation; and (3) to measure the thermal degradation of Jet A and an…11 pp19800020824
- Experimental study of vertical impacts of an LM-type landing gear assembly under simulated lunar gravityVertical impacts of LM-type landing gear system under simulated lunar landings56 ppNASA-TN-D-4711
- Experimental Verification of Boundary-Layer Corrections in Hypersonic NozzlesThe problem of accurately predicting boundary-layer growth for supersonic nozzle design assumes increased importance as the design Mach Number of the nozzles is pushed into the hypersonic regime. Several methods of calculating this growth have been advanced which vary in ease of computation and…2 pp20150021017
- Experimentally Determined Effects of Varying Pitch and Control Stiffnesses on the Flutter Characteristics at Supersonic Speeds of All-movable Wing and Tail ModelsPitch and control stiffness effects on flutter characteristics of all-moveable wing and vertical and horizontal tails on fighter aircraft at supersonic speeds47 pp19660024794
- Exploration of the Versatile Electrically Augmented Turbine Engine Gearbox ConceptIntegration of electric machines with the shafts of gas turbine engines is implied in various electrified aircraft propulsion concepts. This includes implementation of the Turbine Electrified Energy Management (TEEM) concept, a motivator for the Versatile Electrically Augmented Turbine Engine…12 pp
- Exploration of the Versatile Electrically Augmented Turbine Engine Gearbox ConceptIntegration of electric machines with the shafts of gas turbine engines is implied in various electrified aircraft propulsion concepts. This includes implementation of the Turbine Electrified Energy Management (TEEM) concept, a motivator for the Versatile Electrically Augmented Turbine Engine…23 pp
- Exploratory flight investigation and analysis of structural loads encountered by a helicopter hingeless rotor systemFlight test and analysis of structural loads in helicopter hingeless rotor system47 ppNASA-TN-D-3676
- Exploratory piloted simulator study of the effects of winglets on handling qualities of a representative agricultural airplaneThe effects on handling qualities of adding winglets to a representative agricultural aircraft configuration during swath-run maneuvering were evaluated. Aerodynamic data used in the simulation were based on low-speed wind tunnel tests of a full scale airplane and a subscale model. The…44 pp19800019869
- Exploring Advanced Technology Gas Turbine Engine Design and Performance for the Large Civil Tiltrotor (LCTR)A Large Civil Tiltrotor (LCTR) conceptual design was developed as part of the NASA Heavy Lift Rotorcraft Systems Investigation in order to establish a consistent basis for evaluating the benefits of advanced technology for large tiltrotors. The concept has since evolved into the second-generation…18 pp20140016836
- Extraction of Lateral-Directional Stability and Control Derivatives for the Basic F-18 Aircraft at High Angles of AttackThe results of parameter identification to determine the lateral-directional stability and control derivatives of an F-18 research aircraft in its basic hardware and software configuration are presented. The derivatives are estimated from dynamic flight data using a specialized identification…42 ppNASA-TM-4786
- F-106B airplane active control landing gear drop test performanceAircraft dynamic loads and vibrations resulting from landing impact and from runway and taxiway unevenness are recognized as significant factors in causing fatigue damage, dynamic stress on the airframe, crew and passenger discomfort, and reduction of the pilot's ability to control the aircraft…14 ppNASA-TM-102741
- F-15 flight flutter test programThe modes to be observed during the F-15 flight flutter test program were selected on the basis of the results of analytical studies, wind tunnel tests, and ground vibration tests. The modes (both symmetrical and antisymmetrical) tracked on this basis were: fin first bending, fin torsion, fin tip…19 pp19770014093
- F-15 propulsion systemA brief description of the NASA F-15 research aircraft propulsion system is given. The F-15 is powered by two PW1128 afterburning turbofan engines which are growth versions of the F100-PW-100 engine. The PW1128 is controlled by a full-authority digital electronic engine control (DEEC). The F-15…4 pp19950026591
- F-15B QuietSpike(TradeMark) Aeroservoelastic Flight Test Data AnalysisSystem identification or mathematical modelling is utilised in the aerospace community for the development of simulation models for robust control law design. These models are often described as linear, time-invariant processes and assumed to be uniform throughout the flight envelope. Nevertheless,…14 pp20070028827
- F-15B/Flight Test Fixture 2: A Test Bed for Flight ResearchNASA Dryden Flight Research Center has developed a second-generation flight test fixture for use as a generic test bed for aerodynamic and fluid mechanics research. The Flight Test Fixture 2 (FTF-2) is a low-aspect-ratio vertical fin-like shape that is mounted on the centerline of the F-I5B lower…54 pp19970005357
- F100 engine diagnostic system status to dateAn engine diagnostic system, proposed for the F100 engine, was tested in five specially modified Tactical Air Command F-15 aircraft during a 16-month flight evaluation. After more than 3300 engine operating hours encompassing almost 900 flights during the flight evaluation, these aircraft provided…18 pp19810022668
- Factors affecting handling qualities of a lift-fan aircraft during steep terminal area approachesThe XV-5B lift-fan aircraft was used to explore the factors affecting handling qualities in the terminal area. A 10 deg ILS approach task was selected to explore these problems. Interception of the glide slope at 457.2 m, glide slope tracking, deceleration along the glide slope to a spot hover were…26 pp19750014241
- Factors influencing aircraft ground handling performanceProblems associated with aircraft ground handling operations on wet runways are discussed and major factors which influence tire/runway braking and cornering traction capability are identified including runway characteristics, tire hydroplaning, brake system anomalies, and pilot inputs. Research…31 pp19830019708
- Fan Noise for a Concept Commercial Supersonic TransportNASA is currently studying a commercial supersonic transport (CST) aircraft that could carry 35+ passengers at Mach 1.6+ with a 4000+nm range. The aircraft should also meet environmental goals for sonic boom, airport noise and emissions at cruise. With respect to airport noise, considerable effort…13 ppGRC-E-DAA-TN43063
- Fan Noise for a Concept Commercial Supersonic TransportNASA is currently studying a commercial supersonic transport (CST) aircraft that could carry 35+ passengers at Mach 1.6+ with a 4000+nm range. The aircraft should also meet environmental goals for sonic boom, airport noise and emissions at cruise. With respect to airport noise, considerable effort…20 ppGRC-E-DAA-TN44248
- Fan Noise Prediction with Applications to Aircraft System Noise AssessmentThis paper describes an assessment of current fan noise prediction tools by comparing measured and predicted sideline acoustic levels from a benchmark fan noise wind tunnel test. Specifically, an empirical method and newly developed coupled computational approach are utilized to predict aft fan…16 pp20090020420
- Fatigue behavior of a fusion welded Ti 8A1 1M0 1V simulated wing structure under the environment of a supersonic transportFatigue behavior of fusion welded structural assembly with supersonic transport application77 ppNASA-CR-881
- Fatigue of compositesThe failure mechanisms in the fatigue of composite materials are analyzed in terms of the requirements for designing fatigue-critical composite structures. Fiber reinforced polymers, fiber reinforced metals, fatigue of composite structures, and composite design considerations are discussed. It is…32 pp
- Fatigue tests on big structure assemblies of concorde aircraftFatigue tests on structural assemblies of the Concorde supersonic transport aircraft are reported. Two main sections of the aircraft were subjected to pressure, mechanical load, and thermal static tests. The types of fatigue tests conducted and the results obtained are discussed. It was concluded…18 pp
- Feasibility of Electrified Propulsion for Ultra-Efficient Commercial Aircraft Final ReportMIT, Aurora Flight Sciences, and USC have collaborated to assess the feasibility of electric, hybridelectric, and turbo-electric propulsion for ultra-efficient commercial transportation. The work has drawn on the team expertise in disciplines related to aircraft design, propulsion-airframe…100 pp20190033478
- Feasibility of making sound power measurements in the NASA Langley V/STOL tunnel test sectionBased on exploratory acoustic measurements in Langley's V/STOL wind tunnel, recommendations are made on the methodology for making sound power measurements of aircraft components in the closed tunnel test section. During airflow, tunnel self-noise and microphone flow-induced noise place…41 ppNASA-TM-X-73934
- Fighter aircraft flight control technology design requirementsThe evolution of fighter aircraft flight control technology is briefly surveyed. Systems engineering, battle damage considerations for adaptive flutter suppression, in-flight simulation, and artificial intelligence are briefly discussed.9 pp
- FIN LOADS AND TIP-CONTROL HINGE MOMENTS ON A 1 8-SCALE MODEL SIMULATING THE FIRST STAGE OF THE SCOUT RESEARCH VEHICLE AT A MACH NUMBER OF 2.01Supersonic wind tunnel testing - scout vehicle fin load and tip control hinge moments22 pp19630007588
- First Landing of Bell X-2 Research AirplaneThe Bell X-2 supersonic research airplane is equipped with a skid main landing gear and a nose wheel. Pending completion of the rocket engine, glide flights are being performed to determine low-speed handling qualities of the airplane and the landing characteristics with the skid-type landing gear.…. The publisher removed this document from its site; this copy is preserved from the Internet Archive.18 pp19930087318
- Fixed-base simulator pilot rating surveys for predicting lateral-directional handling qualities and pilot rating variabilityPilot ratings of lateral directional handling for wide range of aircraft characteristics - graphs116 pp19690026384
- Flexible aircraft flying and ride qualitiesA brief analytic exposition is presented to illustrate a central principle in flexible mode control, some of the pertinent pilot centered requirements are listed and discussed. The desired features of the control methodology are exposed and the methodology to be used is selected. The example Boeing…24 pp19840012504
- Flexible Wing Model for Structural Sizing and Multidisciplinary Design Optimization of a Strut-Braced WingThis paper describes a structural and aeroelastic model for wing sizing and weight calculation of a strut-braced wing. The wing weight is calculated using a newly developed structural weight analysis module considering the special nature of strut-braced wings. A specially developed aeroelastic…13 pp20000023179
- FLEXSTAB: A computer program for the prediction of loads and stability and control of flexible aircraftCapabilities of the FLEXSTAB Computer Program System are described and illustrated. Aeroelastic analysis of a wide variety of aircraft configurations is performed. The aerodynamic theory used in FLEXSTAB is applicable to both steady and unsteady, subsonic and supersonic flow for multiple wing-body…32 pp
- Flight and wind-tunnel comparisons of the inlet-airframe interaction of the F-15 airplaneThe design of inlets and nozzles and their interactions with the airplane which may account for a large percentage of the total drag of modern high performance aircraft is discussed. The inlet/airframe interactions program and the flight tests conducted is described. Inlet drag and lift data from a…35 pp19850004576
- Flight Control of Flexible AircraftThis presentation presents an overview of flight control research for flexible high aspect wing aircraft in support of the NASA ARMD Advanced Air Transport Technology (AATT) project. It summarizes multi-objective flight control technology being developed for drag optimization, flutter suppression,…40 ppARC-E-DAA-TN39476
- Flight control synthesis for flexible aircraft using Eigenspace assignmentThe use of eigenspace assignment techniques to synthesize flight control systems for flexible aircraft is explored. Eigenspace assignment techniques are used to achieve a specified desired eigenspace, chosen to yield desirable system impulse residue magnitudes for selected system responses. Two of…231 ppNASA-CR-178164
- Flight control systems properties and problems. Volume 2: Block diagram compendiumA compendium of stability augmentation system and autopilot block diagrams is presented. Descriptive materials for 48 different types of aircraft systems are provided. A broad representation of the many mechanical approaches which have been used for aircraft control is developed.152 ppNASA-CR-2501
- Flight Dynamics Analysis BranchThis report summarizes the major activities and accomplishments carried out by the Flight Dynamics Analysis Branch (FDAB), Code 572, in support of flight projects and technology development initiatives in fiscal year 2000. The report is intended to serve as a summary of the type of support carried…58 ppNASA/TM-2000-209971
- Flight Dynamics Conceptual Design Exploration of Multirotor eVTOLThe advent of electric propulsion is revolutionizing the paradigm of rotorcraft design, leading to new electric Vertical Take-Off and Landing (eVTOL) aircraft. Direct drive topologies are common within these new designs, and some designers have chosen to utilize this mechanism for Primary Flight…20 pp
- Flight Dynamics Prediction for Scaled Mars RotorcraftThe use of sub-scale vehicles as a means of predicting full-scale vehicle behavior has historically been applied to flight dynamics testing and evaluation for aircraft operating in Earth atmospheric conditions. However, the use of sub-scale testing on Earth has not been as thoroughly explored for…16 pp
- Flight evaluation of angle of attack as a control parameter in general-aviation aircraftInvestigation of angle of attack information display for pilots to increase efficiency of general aviation aircraft operation25 pp19710008967
- Flight evaluation of the M2-F3 lifting body handling qualities at Mach numbers from 0.30 to 1.61Percentage distributions of 423 pilot ratings obtained from 27 flights are used to indicate the general level of handling qualities of the M2-F3 lifting body. Percentage distributions are compared on the basis of longitudinal and lateral-directional handling qualities, control system, control…46 pp19750018943
- Flight evaluation of the transonic stability and control characteristics of an airplane incorporating a supercritical wingA TF-8A airplane was equipped with a transport type supercritical wing and fuselage fairings to evaluate predicted performance improvements for cruise at transonic speeds. A comparison of aerodynamic derivatives extracted from flight and wind tunnel data showed that static longitudinal stability,…62 ppNASA-TP-1167
- Flight evaluation results from the general-aviation advanced avionics system programA demonstration advanced avionics system (DAAS) for general-aviation aircraft was tested at NASA Ames Research Center to provide information required for the design of reliable, low-cost, advanced avionics systems which would make general-aviation operations safer and more practicable. Guest pilots…16 ppNASA-TM-84397
- Flight Experience With Lightweight, Low-Power Miniaturized Instrumentation SystemsEngineers at the NASA Dryden Flight Research Facility (NASA-Dryden) have conducted two flight research programs with lightweight, low-power miniaturized instrumentation systems built around commercial data loggers. One program quantified the performance of a radio-controlled model airplane. The…14 ppAIAA-92-4111
- Flight Experiment Investigation of General Aviation Self-Separation and Sequencing TasksA new flight operations concept called Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) was developed to increase capacity during Instrument Meteorological Conditions (IMC) at non-towered, non-radar airports by enabling concurrent operations of multiple aircraft. One…72 pp20050176384
- Flight flutter testing of multi-jet aircraftExtensive flight flutter tests were conducted by BAC on B-52 and KC-135 prototype airplanes. The need for and importance of these flight flutter programs to Boeing airplane design are discussed. Basic concepts of flight flutter testing of multi-jet aircraft and analysis of the test data will be…8 pp19760003021
- Flight Flutter Testing of Rotary Wing Aircraft Using a Control System Oscillation TechniqueA flight flutter testing technique is described in which the rotor controls are oscillated by series actuators to excite the rotor and airframe modes of interest, which are then allowed to decay. The moving block technique is then used to determine the damped frequency and damping variation with…12 pp19770014097
- Flight Flutter Testing of Supersonic InterceptorsA summary is presented of experiences in connection with flight flutter testing of supersonic interceptors. The planning and operational aspects involved are described along with the difficulties encountered, and the correlation between measurement and theory. Recommendations for future research…10 pp19760003022
- Flight Flutter Testing of the P6MOn the P6M the shake behavior, i.e., the response to random excitation at subcritical speeds of lowly damped airplane modes, is as important as the actual flutter speed. The approach is to first study the problem by means of analyses and wind-tunnel tests. These predictions are compared with flight…6 pp19760003019
- Flight Flutter Testing SymposiumPapers presented at the conference are reported. Subjects discussed include: theory, methods and techniques, and flight flutter testing.200 pp19760003007
- Flight flutter testing the B-58 airplaneThe flight flutter tests on the B-58 airplane are described, and the philosophy of flight flutter testing is discussed. The instrumentation used in the airplane and in the telemetering receiving station on the ground is described along with the methods used for exciting the airplane and the flight…5 pp19760003023
- Flight flutter testing using pulse techniquesA case of flutter developed at a speed lower than had been flown previously. This incident precipitated the routine procedure of pulsing control surfaces as well as the firing of explosive charges during speed build-ups. In the interest of rapid evaluation of results, simple methods of data…4 pp19760003016
- Flight investigation of an on-off control for V/STOL aircraft under visual conditionsHelicopter flight test of on-off pitch and roll control for V/STOL aircraft under visual conditions27 pp19660018747
- Flight investigation of dynamic stability and control characteristics of a 0.18-scale model of a fan-in-wing VTOL airplaneDynamic stability and control characteristics of 0.18 scale model of fan-in-wing VTOL aircraft36 ppNASA-TN-D-3412
- Flight investigation of piloting techniques and crosswind limitations using a research type crosswind landing gearA research-type crosswind landing gear was tested in a flight program which used a light STOL transport in strong crosswind conditions. The research-type crosswind landing gear used enabled the airplane to land to crosswinds up to a magnitude of 25 to 30 knots. Three modes of landing-gear operation…56 ppNASA-TP-1423
- Flight investigation of stability and control characteristics of a 0.18-scale model of a four-duct tandem V/STOL transportFlight stability and control tests of scale model of four-duct tandem V/STOL aircraft50 ppNASA-TN-D-3055
- Flight investigation of stability and control characteristics of a 1/9-scale model of a four-propeller tilt-wing v/stol transportStability & control of 4-propeller, tilt-wing v/stol scale model transport aircraft45 ppNASA-TN-D-2443
- Flight investigation of the aerodynamic properties of an Ogee wingFlight and wind tunnel tests of low speed characteristics of delta wing aircraft modified to Ogee plan form24 ppNASA-TN-D-3071
- Flight Investigation of the Effects of Ice on an I-16 Jet-Propulsion EngineA flight investigation of an I-16 jet propulsion engine installed in the waist compartment of a B-24M airplane was made to determine the effect of induction-system icing on the performance of the engine. Flights were made at inlet-air temperatures of 15 deg, 20 deg., and 25 F, an indicated airspeed…21 ppNACA-RM-E7A20a
- Flight Investigation of the Stability and Control Characteristics of a 1/4-Scale Model of a Tilt-Wing Vertical-Take-Off-and-Landing AircraftAn experimental investigation has been conducted to determine the dynamic stability and control characteristics of a tilt-wing vertical-take-off-and-landing aircraft with the use of a remotely controlled 1/4-scale free-flight model. The model had two propellers with hinged (flapping) blades mounted…24 ppNASA-MEMO-11-4-58L
- Flight Investigation of the Wing-rotor Lift-sharing Characteristics of a Hingeless Rotor Compound HelicopterFlight investigations of wing-rotor lift-sharing characteristics of XH-51 helicopter6 ppNASA-TM-X-61219
- Flight measurements of boundary-layer noise on the X-15Boundary layer noise measurements in X-15 aircraft flight16 pp19660010313
- Flight Measurements of Lateral and Directional Stability and Control Characteristics of the Grumman F8F-1 AirplaneThis paper presents the results of flight tests to determine the lateral and directional stability and control characteristics of the Grumman F8F-1 airplane with three vertical-tail configurations. The data presented herein have no bearing on the performance characteristics of the airplane, which…89 ppNACA-RM-SL7L31
- Flight Measurements of Some of the Flying Qualities and Stability Derivatives of a Supersonic Fighter AirplaneFlight test to determine flying qualities and dynamic stability derivatives of supersonic fighter aircraft78 ppNASA-MEMO-10-7-58L
- Flight measurements of stability and control derivatives of the x-15 research airplane to a mach number of 6.02 and an angle of attack of 25 degFlight test data on longitudinal, lateral, and directional stability and control derivatives of X-15 aircraft49 ppNASA-TN-D-2532
- Flight Measurements of the Flying Qualities of a Lockheed P-80A Airplane (Army No. 44-85099): Longitudinal-Stability and -Control CharacteristicsThis report contains the flight-test results of the longitudinal-stability and -control phase of a general flying qualities investigation of the Lockheed P-80A airplane (Army No. 44-85099). The tests were conducted at indicated airspeeds up to 530 miles per hour (0.76 Mach number) at low altitude…NACA-RM-A7G01
- Flight propulsion control integration for V/STOL aircraftThe goal of the propulsion community is to have the enabling propulsion technologies in place to permit a low risk decision regarding the initiation of a research STOVL supersonic attack fighter aircraft in the mid-1990's. This technology will effectively integrate, enhance, and extend the…22 pp19880002298
- Flight simulator for hypersonic vehicle and a study of NASP handling qualitiesThe research goal of the Human-Machine Systems Engineering Group was to study the existing handling quality studies in aircraft with sonic to supersonic speeds and power in order to understand information requirements needed for a hypersonic vehicle flight simulator. This goal falls within the NASA…8 pp19930010267
- Flight Stability and Control and Performance Results from the Linear Aerospike SR-71 Experiment (LASRE)The Linear Aerospike SR-71 Experiment (LASRE) is presently being conducted to test a 20-percent-scale version of the Linear Aerospike rocket engine. This rocket engine has been chosen to power the X-33 Single Stage to Orbit Technology Demonstrator Vehicle. The rocket engine was integrated into a…30 ppNASA/TM-1998-206565
- Flight Systems Integration & Test: Lessons Learned for Future SuccessThis paper offers a comprehensive view of flight system integration and test (I&T) lessons learned related to mishaps and close calls, focusing on what can be done to improve the I&T process to avoid recurrence. Specific areas within the realm of I&T that are covered in this paper include: I&T team…29 pp20180003229
- Flight test and evaluation of Omega navigation for general aviationA seventy hour flight test program was performed to determine the suitability and accuracy of a low cost Omega navigation receiver in a general aviation aircraft. An analysis was made of signal availability in two widely separated geographic areas. Comparison is made of the results of these flights…267 pp19750017829
- Flight test and evaluation of Omega navigation in a general aviation aircraft. Volume 1: TechnicalA low cost flight research program was conducted to evaluate the performance of differential Omega navigation in a general aviation aircraft. The flight program consisted of two distinct parts corresponding to the two major objectives of the study. The Wallops Flight Program was conducted to obtain…126 pp19760011006
- Flight Test Approach to Adaptive Control ResearchThe National Aeronautics and Space Administration s Dryden Flight Research Center completed flight testing of adaptive controls research on a full-scale F-18 testbed. The validation of adaptive controls has the potential to enhance safety in the presence of adverse conditions such as structural…15 pp20110024034
- Flight Test EngineeringAlthough the scope of flight test engineering efforts may vary among organizations, all point to a common theme: flight test engineering is an interdisciplinary effort to test an asset in its operational flight environment. Upfront planning where design, implementation, and test efforts are clearly…25 ppDFRC-E-DAA-TN11035
- Flight test experience with the F-8 digital fly-by-wire systemFlight test results of the F-8 digital fly-by-wire (DFBW) control system are presented and the implications for application to active control technology (ACT) are discussed. The F-8 DFBW system has several of the attributes of proposed ACT systems, so the flight test experience is helpful in…54 pp19750010179
- Flight Test Hazard Planning Near the Speed of LightA viewgraph presentation describing flight test safety near the speed of light is shown. The topics include: 1) Concept; 2) Portal Content; 3) Activity to Date; 4) FTS Database Updatd FAA Program; 5) FAA Flight Test Risk Management; 6) CFR 14 Part 21.35 Current and proposed changes; 7) An Online…46 pp
- Flight Test Implementation of a Second Generation Intelligent Flight Control SystemThe NASA F-15 Intelligent Flight Control System project team has developed a series of flight control concepts designed to demonstrate the benefits of a neural network-based adaptive controller. The objective of the team was to develop and flight-test control systems that use neural network…19 pp20050238105
- Flight test investigation of certification issues pertaining to general-aviation-type aircraft with natural laminar flowDevelopment of Natural Laminar Flow (NLF) technology for application to general aviation-type aircraft has raised some question as to the adequacy of FAR Part 23 for certification of aircraft with significant NLF. A series of flight tests were conducted with a modified Cessna T210R to allow…51 pp19900011636
- Flight Test of the F/A-18 Active Aeroelastic Wing AirplaneSuccessful flight-testing of the Active Aeroelastic Wing airplane was completed in March 2005. This program, which started in 1996, was a joint activity sponsored by NASA, Air Force Research Laboratory, and industry contractors. The test program contained two flight test phases conducted in early…31 pp20050204120
- Flight Test of the F/A-18 Active Aeroelastic Wing AirplaneSuccessful flight-testing of the Active Aeroelastic Wing airplane was completed in March 2005. This program, which started in 1996, was a joint activity sponsored by NASA, Air Force Research Laboratory, and industry contractors. The test program contained two flight test phases conducted in early…43 pp20050212234
- Flight Test Overview for UAS Integration in the NAS ProjectThe National Aeronautics and Space Administration is conducting a series of flight tests intended to support the reduction of barriers that prevent unmanned aircraft from flying without the required waivers from the Federal Aviation Administration. The most recent testing supported two separate…11 pp20160000425
- Flight test report of the NASA icing research airplane: Performance, stability, and control after flight through natural icing conditionsFlight test results are presented documenting the effect of airframe icing on performance and stability and control of a NASA DHC-6 icing research aircraft. Kohlman System Research, Inc., provided the data acquisition system and data analysis under contract to NASA. Performance modeling methods and…174 ppNASA-CR-179515
- Flight Test Results From a Supercritical Mission Adaptive Wing With Smooth Variable CamberThe mission adaptive wing (MAW) consisted of leading- and trailing-edge variable-camber surfaces that could be deflected in flight to provide a near-ideal wing camber shape for any flight condition. These surfaces featured smooth, flexible upper surfaces and fully enclosed lower surfaces,…28 ppAIAA-92-4101
- Flight Test Results of an Axisymmetric Channeled Center Body Supersonic Inlet at Off-Design ConditionsFlight-testing of a channeled center-body axisymmetric supersonic inlet design concept was conducted at the National Aeronautics and Space Administration (NASA) Dryden Flight Research Center in collaboration with the NASA Glenn Research Center (Cleveland, Ohio) and TechLand Research, Inc. (North…17 pp20140000927
- Flight Test Results on the Stability and Control of the F-15 Quiet Spike(TradeMark) AircraftThe Quiet Spike F-15B flight research program investigated supersonic shock reduction using a 24-ft sub-scale telescoping nose boom on an F-15B airplane. The program primary flight test objective was to collect flight data for aerodynamic and structural models validation up to 1.8 Mach. Other…45 ppNASA/TM-2012-215978
- Flight Test Series 3: Flight Test ReportThis document is a flight test report from the Operational perspective for Flight Test Series 3, a subpart of the Unmanned Aircraft System (UAS) Integration in the National Airspace System (NAS) project. Flight Test Series 3 testing began on June 15, 2015, and concluded on August 12, 2015.…342 ppDFRC-E-DAA-TN28830
- Flight Test Techniques Used to Evaluate Performance Benefits During Formation FlightThe Autonomous Formation Flight research project has been implemented at the NASA Dryden Flight Research Center to demonstrate the benefits of formation flight and develop advanced technologies to facilitate exploiting these benefits. Two F/A-18 aircraft have been modified to precisely control and…25 pp20030005804
- Flight testing air-to-air missiles for flutterThe philosophy of the design of air-to-air missiles and hence of flight testing them for flutter differs from that of manned aircraft. Primary emphasis is put on analytical and laboratory evaluation of missile susceptibility to aeroelastic and aero-servo-elastic instabilities and uses flight…3 pp19760003027
- Flight Testing and Simulation of an F-15 Airplane Using Throttles for Flight ControlFlight tests and simulation studies using the throttles of an F-15 airplane for emergency flight control have been conducted at the NASA Dryden Flight Research Facility. The airplane and the simulation are capable of extended up-and-away flight, using only throttles for flightpath control. Initial…18 ppAIAA-92-4109
- Flight Testing and Simulation of an F-15 Airplane Using Throttles for Flight ControlFlight tests and simulation studies using the throttles of an F-15 airplane for emergency flight control have been conducted at the NASA Dryden Flight Research Facility. The airplane and the simulation are capable of extended up-and-away flight, using only throttles for flight path control. Initial…24 ppNASA-TM-104255
- Flight Testing the Rotor Systems Research Aircraft (RSRA)In the late 1960s, efforts to advance the state-of-the-art in rotor systems technology indicated a significant gap existed between our ability to accurately predict the characteristics of a complex rotor system and the results obtained through flight verification. Even full scale wind tunnel…17 pp19840005109
- Flight tests of a one-man helicopter and com- parison of its handling qualities with those of larger vtol aircraftFlight tests of one-man helicopter and comparison of handling qualities17 pp19650025802
- Flight Tests of a Supersonic Natural Laminar Flow AirfoilA flight-test campaign of a supersonic natural laminar flow airfoil has been recently completed. The test surface was an 80-inch (203 cm) chord and 40-inch (102 cm) span article mounted on the centerline store location of an F-15B airplane (McDonnell Douglas Corporation, now The Boeing Company,…33 ppNASA/TM-2015-218940
- Flight Tests of a Supersonic Natural Laminar Flow AirfoilIR thermography was used to characterize the transition front on a S-NLF test article at chord Reynolds numbers in excess of 30 million Changes in transition due to Mach number, Reynolds number, and surface roughness were investigated - Regions of laminar flow in excess of 80% chord at chord…20 ppAFRC-E-DAA-TN14871
- Flight Validation of a Handling Qualities Metric for a Damaged AircraftObjectives: a) Develop an asymmetric handling qualities metric to predict cross coupling effects of a damaged aircraft: 1) Initial use of U.S Army Aeronautical Design Specification ADS-33; 2) Modification as required based on flight test results. b) Simulation and Flight Validation of proposed…16 pp20090040729
- Flight-determined stability and control coefficients of the F-111A airplaneA complete set of linear stability and control derivatives of the F-111A airplane was determined with a modified maximum likelihood estimator. The derivatives were determined at wing sweep angles of 26 deg, 35 deg, and 58 deg. The flight conditions included a Mach number range of 0.63 to 1.43 and…91 ppNASA-TM-72851
- Flight-determined stability and control derivatives for the F-111 Tact research aircraftA flight investigation was conducted to provide a stability and control derivative data base for the F-111 transonic aircraft technology research aircraft. Longitudinal and lateral-directional data were obtained as functions of Mach number, angle of attack, and wing sweep. For selected derivatives,…80 ppNASA-TP-1350
- FLIGHT-DETERMINED STABILITY AND CONTROL DERIVATIVES OF A SUPERSONIC AIRPLANE WITH A LOW-ASPECT-RATIO UNSWEPT WING AND A TEE-TAILFlight-determined stability & control derivatives of supersonic aircraft with low aspect ratio unswept wing & t-tail42 ppNASA-MEMO-2-2-59H
- Flight-Determined Subsonic Longitudinal Stability and Control Derivatives of the F-18 High Angle of Attack Research Vehicle (HARV) with Thrust VectoringThe subsonic longitudinal stability and control derivatives of the F-18 High Angle of Attack Research Vehicle (HARV) are extracted from dynamic flight data using a maximum likelihood parameter identification technique. The technique uses the linearized aircraft equations of motion in their…72 ppNASA/TP-97-206539
- Flight-Test Evaluation of Landing Gear Noise Reduction TechnologiesResults from the third Acoustics Research Measurements flight test, conducted under the NASA Flight Demonstrations and Capabilities project, are presented and discussed. The test evaluated landing gear and gear cavity noise mitigation technologies installed on a NASA Gulfstream G-III. Aircraft…19 ppNF1676L-31577
- Flight-Test Evaluation of Landing Gear Noise Reduction TechnologiesResults from the third Acoustics Research Measurements flight test, conducted under the NASA Flight Demonstrations and Capabilities project, are presented and discussed. The test evaluated landing gear and gear cavity noise mitigation technologies installed on a NASA Gulfstream G-III. Aircraft…19 pp
- Flight-Test Evaluation of the Longitudinal Stability and Control Characteristics of 0.5-Scale Models of the Fairchild Lark Pilotless-Aircraft Configuration: Standard Configuration with Wing Flaps Deflected 60 Degrees and Model having Tail in Line with Wings, TED No. NACA 2387Flight tests were conducted at the Flight Test Station of the Pilotless Aircraft Research Division at Wallop Island, Va., to determine the longitudinal control and stability characteristics of 0.5-scale models of the Fairchild Lark pilotless aircraft with the tail in line with the wings a d with…30 ppNACA-RM-L7F17
- Flight-Test Evaluation of the Longitudinal Stability and Control Characteristics of 0.5-Scale Models of the Fairchild Lark Pilotless-Aircraft Configuration. Model with Wing Flaps Deflected 15 Degrees, TED No. NACA 2387A flight test was conducted at the Flight Test Station of the Pilotless Aircraft Research Division at Wallops Island, Va., to determine the longitudinal control and stability characteristics of a 0.5-scale model of the Fairchild Lerk Pilotless aircraft with the horizontal wing flaps deflected 15…20 ppNACA-RM-L6J28a
- Flightworthy active control landing gear for a supersonic aircraftA flightworthy active control landing gear system for a supersonic aircraft was designed to minimize aircraft loads during takeoff, impact, rollout, and taxi. The design consists of hydromechanical modifications to the existing gear and the development of a fail-safe electronic controller.…142 ppNASA-CR-3298
- Flow-Field Investigation of Gear-Flap Interaction on a Gulfstream Aircraft ModelOff-surface flow measurements of a high-fidelity 18% scale Gulfstream aircraft model in landing configuration with the main landing gear deployed are presented. Particle Image Velocimetry (PIV) and Laser Velocimetry (LV) were used to measure instantaneous velocities in the immediate vicinity of the…18 pp20150000560
- Flutter analysis of composite box beamsThe dynamic aeroelastic instability of flutter is an important factor in the design of modern high-speed, flexible aircraft. The current trend is toward the creative use of composites to delay flutter. To obtain an optimum design, we need an accurate as well as efficient model. As a first step…14 pp19950016972
- Flutter analysis of flat rectangular panels based on three-dimensional supersonic potential flowFlutter of flat rectangular panels based on three-dimensional supersonic potential flow7 pp19640000222
- Flutter Analysis of the Transonic Truss-Braced Wing Aircraft Using Transonic CorrectionThis paper describes a flutter analysis method for the Transonic Truss-Braced Wing aircraft using a vortex lattice method coupled to an unsteady transonic correction method to account for unsteady aerodynamics in transonic flow. A steady-state vortex-lattice model of the Truss-Braced Wing aircraft…25 pp20200002955
- Flutter optimization in fighter aircraft designThe efficient design of aircraft structure involves a series of compromises among various engineering disciplines. These compromises are necessary to ensure the best overall design. To effectively reconcile the various technical constraints requires a number of design iterations, with the…17 pp19870002288
- Flutter Prediction for Aircraft Conceptual DesignFlutter prediction is usually a knowledge-based analysis process that aims to reduce the cost of aeroelastic stability margin certification. However, early detection of flutter problems is beneficial in the development of unconventional aircraft. The recently developed automation tool ConceptFEA…16 pp20200002364
- Flutter suppression digital control law design and testing for the AFW wind tunnel modelThe design of a control law for simultaneously suppressing the symmetric and antisymmetric flutter modes of a sting mounted fixed-in-roll aeroelastic wind-tunnel model is described. The flutter suppression control law was designed using linear quadratic Gaussian theory, and it also involved control…16 pp19940031366
- Flutter suppression digital control law design and testing for the AFW wind-tunnel modelDesign of a control law for simultaneously suppressing the symmetric and antisymmetric flutter modes of a string mounted fixed-in-roll aeroelastic wind tunnel model is described. The flutter suppression control law was designed using linear quadratic Gaussian theory and involved control law order…10 ppNASA-TM-107652
- Flying qualities and control system characteristics for superaugmented aircraftAircraft-alone dynamics and superaugmented control system fundamental regulatory properties including stability and regulatory responses of the basic closed-loop systems; fundamental high and low frequency margins and governing factors; and sensitivity to aircraft and controller parameters are…120 ppNASA-CR-170419
- Flying Qualities Evaluation of a Commuter Aircraft With an Ice Contaminated TailplaneDuring the NASA/FAA (Federal Aviation Administration) Tailplane Icing Program, pilot evaluations of aircraft flying qualities were conducted with various ice shapes attached to the horizontal tailplane of the NASA Twin Otter Icing Research Aircraft. Initially, only NASA pilots conducted these…14 pp20000120385
- Flying Quality Analysis of a JAS 39 Gripen Ministick Controller in an F/A-18 AircraftNASA Dryden conducted a handling qualities experiment using a small displacement centerstick controller that Saab-Scania developed for the JAS 39 Gripen aircraft. The centerstick, or ministick, was mounted in the rear cockpit of an F/A-18 aircraft. Production support flight control computers…20 pp20000080122
- Flying-qualities criteria for wings-level-turn maneuvering during an air-to-ground weapon delivery taskA moving base simulator experiment demonstrated that a wings-level-turn control mode improved flying qualities for air to ground weapon delivery compared with those of a conventionally controlled aircraft. Evaluations of criteria for dynamic response for this system have shown that pilot ratings…96 pp19810012554
- Follow on Research for Multi-Utility Technology Test Bed Aircraft at NASA Dryden Flight Research Center (FY13 Progress Report)Modern aircraft employ a significant fraction of their weight in composite materials to reduce weight and improve performance. Aircraft aeroservoelastic models are typically characterized by significant levels of model parameter uncertainty due to the composite manufacturing process. Small modeling…56 pp20140010815
- Force-Test Investigation of the Stability and Control Characteristics of a 1/4-Scale Model of a Tilt-Wing Vertical-Take-Off-and-Landing AircraftA wind-tunnel investigation has been made to determine the aerodynamic characteristics of a 1/4-scale model of a tilt-wing vertical-take-off-and-landing aircraft. The model had two 3-blade single-rotation propellers with hinged (flapping) blades mounted on the wing, which could be tilted from an…58 ppNASA-MEMO-11-3-58L
- FORCE-TEST INVESTIGATION OF THE STABILITY AND CONTROL CHARACTERISTICS OF A FOUR-PROPELLER TILT-WING VTOL MODEL WITH A PROGRAMED FLAPStability and control characteristics of a four propeller tilt wing vtol model with programmed flap60 ppNASA-TN-D-1389
- Forced Oscillation Wind Tunnel Testing for FASER Flight Research AircraftAs unmanned air vehicles (UAVs) continue to expand their flight envelopes into areas of high angular rate and high angle of attack, modeling the complex unsteady aerodynamics for simulation in these regimes has become more difficult using traditional methods. The goal of this experiment was to…12 ppNF1676L-14053
- Forecast of the general aviation air traffic control environment for the 1980'sThe critical information required for the design of a reliable, low cost, advanced avionics system which would enhance the safety and utility of general aviation is stipulated. Sufficient data is accumulated upon which industry can base the design of a reasonably priced system having the capability…133 pp19760026091
- Free-flight investigation of forebody blowing for stability and controlA free-flight wind-tunnel investigation was conducted on a generic fighter model with forebody pneumatic vortex control for high angle-of-attack directional control. This is believed to be the first flight demonstration of a forebody blowing concept integrated into a closed-loop flight control…12 ppNASA-TM-111595
- Freezing Rain as an In-Flight Icing HazardExposure to supercooled large drops (SLD-subfreezing water droplets with diameters greater than approx. 50 microns) can pose a significant threat to the safety of some aircraft. Although SLD includes both freezing drizzle (FZDZ) and freezing rain (FZRA), much of the SLD research and development of…12 pp20000063509
- Frequencies and Flutter Speed Estimation for Damaged Aircraft Wing Using Scaled Equivalent Plate AnalysisEquivalent plate analysis is often used to replace the computationally expensive finite element analysis in initial design stages or in conceptual design of aircraft wing structures. The equivalent plate model can also be used to design a wind tunnel model to match the stiffness characteristics of…13 pp20100016275
- Frostwing Co-Operation in Aircraft Icing Researche aerodynamic effects of Cold Soaked Fuel Frost have become increasingly significant as airworthiness authorities have been asked to allow it during aircraft take-off. The Federal Aviation Administration and the Finnish Transport Safety Agency signed a Research Agreement in aircraft icing research…12 ppGRC-E-DAA-TN66819
- Fuel conservation merits of advanced turboprop transport aircraftThe advantages of a propfan powered aircraft for the commercial air transportation system were assessed by the comparison with an equivalent turbofan transport. Comparisons were accomplished on the basis of fuel utilization and operating costs, as well as aircraft weight and size. Advantages of the…156 pp19780013152
- Fuel conservation possibilities for terminal area compatible aircraftDesign features and operational procedures are identified, which would reduce fuel consumption of future transport aircraft. The fuel-saving potential can be realized during the last decade of this century only if the necessary research and technology programs are implemented in the areas of…235 pp19750011152
- Fuel conservative aircraft engine technologyTechnology developments for more fuel-efficiency subsonic transport aircraft are reported. Three major propulsion projects were considered: (1) engine component improvement - directed at current engines; (2) energy efficient engine - directed at new turbofan engines; and (3) advanced turboprops -…40 pp19780019184
- Fuel system technology overviewFuel system research and technology studies are being conducted to investigate the correlations and interactions of aircraft fuel system design and environment with applicable characteristics of the fuel. Topics include: (1) analysis of in-flight fuel temperatures; (2) fuel systems for high…9 pp19800020827
- Fuel-Conservation Guidance System for Powered-Lift AircraftA technique is described for the design of fuel-conservative guidance systems and is applied to a system that was flight tested on board NASA's sugmentor wing jet STOL research aircraft. An important operational feature of the system is its ability to rapidly synthesize fuel-efficient trajectories…10 pp19980200857
- Full scale subsonic wind tunnel requirements and design studiesThe justification and requirements are summarized for a large subsonic wind tunnel capable of testing full-scale aircraft, rotor systems, and advanced V/STOL aircraft propulsion systems. The design considerations and constraints for such a facility are reviewed, and the trades between facility test…50 ppNASA-TM-X-62184
- Full-scale dynamic landing-impact investigation of a prototype lunar module landing gearFull scale dynamic landing impact investigation of prototype lunar module landing gear46 ppNASA-TN-D-5029
- FULL-SCALE WIND-TUNNEL INVESTIGATION OF A FLEXIBLE-WING MANNED TEST VEHICLEWind tunnel stability and control tests of flexible wing manned aircraft - parawing73 ppNASA-TN-D-1946
- Full-scale wind-tunnel investigation of a VTOL aircraft with a jet-ejector system for lift augmentationFull scale wind tunnel investigation of VTOL AIRCRAFT with jet ejector system for lift augmentation53 ppNASA-TN-D-3725
- Full-scale wind-tunnel tests of a small unpowered jet aircraft with a T-tailThe aerodynamic characteristics of a full scale executive type jet transport aircraft with a T-tail were investigated in a 40 x 80 ft (12.2 by 24.4 meter) wind tunnel (subsonic). Static, longitudinal, and lateral stability, and control characteristics were determined at angles of attack from -2 deg…104 ppNASA-TN-D-6573
- Fully unsteady subsonic and supersonic potential aerodynamics for complex aircraft configurations with applications to flutterA general formulation is presented for the analysis of steady and unsteady, subsonic and supersonic aerodynamics for complex aircraft configurations. The theoretical formulation, the numerical procedure, the description of the program SOUSSA (steady, oscillatory and unsteady, subsonic and…33 pp19760007990
- FUN3D Solutions for Nose Landing GearAn unstructured grid flow solver, FUN3D has been used for simulation of unsteady flow on a partially dressed nose landing gear with closed cavities. Results obtained from an hybrid RANS/LES and delayed DES turbulence models are presented. Solutions have been obtained for a series of successively…20 ppNF1676L-10874
- Further Examinations of Bimodal SLD Ice Accretion in the NASA Icing Research TunnelAn ice shape database has been created to document ice accretions on a 72-inch chord NACA 23012 airfoil model resulting from an exposure to a Supercooled Large Drop (SLD) icing cloud with a bimodal drop size distribution. The ice shapes created were documented with photographs, laser scanned…10 pp20180006521
- Fuselage-Induced Velocity Model for LRTA, RTA, and HART FuselagesIn order to make the aerodynamic fuselage-rotor interference effects available to comprehensive rotor codes, a simple analytical model of the fuselage-induced velocities within the volume of rotor blade operation above the fuselage is developed here for the following bodies used in wind tunnel…79 pp20180008762
- Future Air Force aircraft propulsion control systems: The extended summary paperHydromechanical control technology simply cannot compete against the performance benefits offered by electronics. Future military aircraft propulsion control systems will be full authority, digital electronic, microprocessor base systems. Anticipating the day when microprocessor technology will…5 pp19810003586
- Future aspects of supersonic transport navigationSupersonic transport navigation, guidance, and integrated avionics system10 ppNASA-TM-X-61039
- Future aviation fuels overviewThe outlook for aviation fuels through the turn of the century is briefly discussed and the general objectives of the NASA Lewis Alternative Aviation Fuels Research Project are outlined. The NASA program involves the evaluation of potential characteristics of future jet aircraft fuels, the…4 pp19800020800
- Future Integrated Systems Concept for Preventing Aircraft Loss-of-Control AccidentsLoss of control remains one of the largest contributors to aircraft fatal accidents worldwide. Aircraft loss-of-control accidents are highly complex in that they can result from numerous causal and contributing factors acting alone or (more often) in combination. Hence, there is no single…17 ppNF1676L-11114
- Fuzzy Logic Decoupled Lateral Control for General Aviation AirplanesIt has been hypothesized that a human pilot uses the same set of generic skills to control a wide variety of aircraft. If this is true, then it should be possible to construct an electronic controller which embodies this generic skill set such that it can successfully control different airplanes…60 pp19970031951
- Fuzzy Logic Decoupled Longitudinal Control for General Aviation AirplanesIt has been hypothesized that a human pilot uses the same set of generic skills to control a wide variety of aircraft. If this is true, then it should be possible to construct an electronic controller which embodies this generic skill set such that it can successfully control difference airplanes…108 pp19970011943
- Fuzzy Model-based Pitch Stabilization and Wing Vibration Suppression of Flexible Wing Aircraft.This paper presents a fuzzy nonlinear controller to regulate the longitudinal dynamics of an aircraft and suppress the bending and torsional vibrations of its flexible wings. The fuzzy controller utilizes full-state feedback with input constraint. First, the Takagi-Sugeno fuzzy linear model is…6 ppARC-E-DAA-TN13844
- Fuzzy Modeling and Parallel Distributed Compensation for Aircraft Flight Control from Simulated Flight DataA method is described that combines fuzzy system identification techniques with Parallel Distributed Compensation (PDC) to develop nonlinear control methods for aircraft using minimal a priori knowledge, as part of NASA’s Learn-to-Fly initiative. A fuzzy model was generated with simulated flight…15 ppNF1676L-30052
- Gaps Analysis for the Development of an IASMS for Commercial Aviation OperationsAn In-time Aviation Safety Management System (IASMS) [1,2] is a set of services, functions, and capabilities (SFCs) necessary for monitoring known hazards and emergent risks, assessing safety data for anomalies, precursors, and trends, mitigating hazards that reach safety thresholds, and assuring…21 ppNASA/TM-20240012528
- Gas turbine engine active clearance controlMethod for controlling the clearance between rotating and stationary components of a gas turbine engine are disclosed. Techniques for achieving close correspondence between the radial position of rotor blade tips and the circumscribing outer air seals are disclosed. In one embodiment turbine case…10 ppPatent Number: US-PATENT-4,513,567
- Gas turbine engine fuel controlA variable orifice system is described that is responsive to compressor inlet pressure and temperature, compressor discharge pressure and rotational speed of a gas-turbine engine. It is incorporated into a hydraulic circuit that includes a zero gradient pump driven at a speed proportional to the…13 ppPatent Application Number: US-PATENT-APPL-SN-147922
- Gas Turbine Engine Having Fan Rotor Driven by Turbine Exhaust and with a BypassA gas turbine engine has a core engine incorporating a core engine turbine. A fan rotor is driven by a fan rotor turbine. The fan rotor turbine is in the path of gases downstream from the core engine turbine. A bypass door is moveable from a closed position at which the gases from the core engine…6 ppPatent Application Number: US-Patent-Appl-SN-13/731,371
- Gas Turbine Engine Inlet Wall DesignA gas turbine engine has an inlet duct formed to have a shape with a first ellipse in one half and a second ellipse in a second half. The second half has an upstream most end which is smaller than the first ellipse. The inlet duct has a surface defining the second ellipse which curves away from the…6 pp20160004236
- Gas Turbine Engine with Air/Fuel Heat ExchangerOne embodiment of the present invention is a unique aircraft propulsion gas turbine engine. Another embodiment is a unique gas turbine engine. Another embodiment is a unique gas turbine engine. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for gas…11 ppPatent Application Number: US-Patent-Appl-SN-14/319,680
- Gas turbine engine with convertible accessoriesDrive means for connecting a gas turbine engine to its accessories are so constructed as to allow the accessories to be selectively positioned to any one of several predetermined circumferential positions about the perimeter of the engine. This feature permits convenient mounting of the same engine…6 ppPatent Number: NASA-CASE-LEW-12390-1
- Gas turbine engine with recirculating bleedCarbon monoxide and unburned hydrocarbon emissions in a gas turbine engine are reduced by bleeding hot air from the engine cycle and introducing it back into the engine upstream of the bleed location and upstream of the combustor inlet. As this hot inlet air is recycled, the combustor inlet…5 ppPatent Number: NASA-CASE-LEW-12452-1
- GASP- General Aviation Synthesis Program. Volume 1: Main program. Part 1: Theoretical developmentThe General Aviation synthesis program performs tasks generally associated with aircraft preliminary design and allows an analyst the capability of performing parametric studies in a rapid manner. GASP emphasizes small fixed-wing aircraft employing propulsion systems varying froma single piston…228 pp19810010562
- General aviation air traffic pattern safety analysisA concept is described for evaluating the general aviation mid-air collision hazard in uncontrolled terminal airspace. Three-dimensional traffic pattern measurements were conducted at uncontrolled and controlled airports. Computer programs for data reduction, storage retrieval and statistical…22 ppNASA-TM-X-69455
- General Aviation Aircraft Reliability StudyThis reliability study was performed in order to provide the aviation community with an estimate of Complex General Aviation (GA) Aircraft System reliability. To successfully improve the safety and reliability for the next generation of GA aircraft, a study of current GA aircraft attributes was…120 ppNASA/CR-2001-210647
- General aviation and community developmentThe summer program is summarized. The reports presented concern (1) general aviation components, (2) general aviation environment, (3) community perspective, and (4) transportation and general aviation in Virginia.266 pp19760004906
- General aviation approach and landing practicesThe characteristics of air traffic patterns at uncontrolled airports and techniques used by a group of general aviation pilots in landing light airplanes are documented. The results of some 1,600 radar tracks taken at four uncontrolled airports and some 600 landings made by 22 pilots in two, four…30 pp
- General aviation avionics equipment maintenanceMaintenance of general aviation avionics equipment was investigated with emphasis on single engine and light twin engine general aviation aircraft. Factors considered include the regulatory agencies, avionics manufacturers, avionics repair stations, the statistical character of the general aviation…71 pp19780016189
- General aviation componentsAn overview is presented of selected aviation vehicles. The capabilities and performance of these vehicles are first presented, followed by a discussion of the aerodynamics, structures and materials, propulsion systems, noise, and configurations of fixed-wing aircraft. Finally the discussion…15 pp19760004907
- General aviation crash safety program at Langley Research CenterThe purpose of the crash safety program is to support development of the technology to define and demonstrate new structural concepts for improved crash safety and occupant survivability in general aviation aircraft. The program involves three basic areas of research: full-scale crash simulation…21 pp
- General Aviation Data FrameworkThe Flight Research Services Directorate at the NASA Langley Research Center (LaRC) provides development and operations services associated with three general aviation (GA) aircraft used for research experiments. The GA aircraft includes a Cessna 206X Stationair, a Lancair Colombia 300X, and a…10 pp20060046507
- General aviation energy-conservation research programs at NASA-Lewis Research CenterThe major thrust of NASA's nonturbine general aviation engine programs is directed toward (1) reduced specific fuel consumption, (2) improved fuel tolerance; and (3) emission reduction. Current and planned future programs in such areas as lean operation, improved fuel management, advanced cooling…26 pp19780009117
- General aviation IFR operational problemsOperational problems of general aviation IFR operators (particularly single pilot operators) were studied. Several statistical bases were assembled and utilized to identify the more serious problems and to demonstrate their magnitude. These bases include official activity projections, historical…214 pp19790013897
- General Aviation Interior Noise: Noise Control Measure Evaluation - Part 3The work reported herein is an extension to the work accomplished under NASA Grant NAG1-2091 on the development of noise/source/path identification techniques for single engine propeller driven General Aviation aircraft. The previous work developed a Conditioned Response Analysis (CRA) technique to…60 ppNASA/CR-2002-211667/PT3
- General Aviation Light Aircraft Propulsion: From the 1940's to the Next CenturyCurrent general aviation light aircraft are powered by engines that were originally designed in the 1940's. This paper gives a brief history of light aircraft engine development, explaining why the air-cooled, horizontally opposed piston engine became the dominant engine for this class of aircraft.…16 pp19980209647
- General Aviation Pilots' Perceived Usage and Valuation of Aviation Weather Information SourcesAviation suffers many accidents due to the lack of good weather information in flight. Existing aviation weather information is difficult to obtain when it is most needed and is not well formatted for in-flight use. Because it is generally presented aurally, aviation weather information is…60 ppNASA/TM-2002-211443
- General aviation piston-engine exhaust emission reductionTo support the promulgation of aircraft regulations, two airports were examined, Van Nuys and Tamiami. It was determined that the carbon monoxide (CO) emissions from piston-engine aircraft have a significant influence on the CO levels in the ambient air in and around airports, where workers and…33 pp19780003130
- General Aviation PropulsionPrograms exploring and demonstrating new technologies in general aviation propulsion are considered. These programs are the quiet, clean, general aviation turbofan (QCGAT) program; the general aviation turbine engine (GATE) study program; the general aviation propeller technology program; and the…. The publisher removed this document from its site; this copy is preserved from the Internet Archive.431 pp19800013840
- General Aviation Propulsion (GAP) Program, Turbine Engine System ElementThe goal of the General Aviation Propulsion (GAP) Program Turbine Engine System Elements is to conduct a shared resource project to develop an affordable gas turbine engine for use on 4 to 6 place, light aircraft that will lead to revitalization of the general aviation industry in the United…12 pp19980010521
- General Aviation Task Force reportGeneral aviation is officially defined as all aviation except scheduled airlines and the military. It is the only air transportation to many communities throughout the world. In order to reverse the recent decline in general aviation aircraft produced in the United States, the Task Force recommends…72 pp19950005050
- General aviation technology assessmentThe existing problem areas in general aviation were investigated in order to identify those which can benefit from technological payoffs. The emphasis was placed on acceptance by the pilot/passenger in areas such as performance, safety, handling qualities, ride quality, etc. Inputs were obtained…54 ppNASA-CR-145979
- General Aviation Turbine Engine (GATE) OverviewWhen all the technology studies were done and the accompanying market analyses were complete, the conclusion was that it is indeed possible to reduce the cost of turbine engines by a factor of 3 using low-cost manufacturing techniques and increased production rates. In the interest of reducing…6 pp19830014186
- General Aviation Turbine Engine (GATE) studyThe feasibility of turbine engines for the smaller general aviation aircraft was investigated and a technology program for developing the necessary technology was identified. Major results included the definition of the 1988 general aviation market, the identification of turboprop and turboshaft…273 pp19810010591
- General overview of dragThe state-of-the-art on aerodynamic drag reduction is briefly reviewed. The various elements making up the total drag of an aircraft include fuselage, wing, nacelles, trim, interference, tail, and cooling drag.26 pp19760003910
- General-aviation pilot reactions to and opinions on grooved runwaysAviation pilot reactions and opinions on grooved runways29 pp19690026483
- Generation and Calibration of Linear Models of Aircraft with Highly Coupled Aeroelastic and Flight DynamicsThe lightweight structures and unconventional configurations being considered for the next generation of aircraft mean that any effort to predict or control the flight dynamics is impacted by the structural dynamics. One of the most severe forms of coupling between aeroelasticity and flight…34 pp20200000419
- Generation of Fullspan Leading-Edge 3D Ice Shapes for Swept-Wing Aerodynamic TestingThe deleterious effect of ice accretion on aircraft is often assessed through dry-air flight and wind tunnel testing with artificial ice shapes. This paper describes a method to create fullspan swept-wing artificial ice shapes from partial span ice segments acquired in the NASA Glenn Icing Reserch…21 pp20170000239
- Generation of Mars Helicopter Rotor Model for Comprehensive AnalysesThe present research is aimed at providing a performance model for the Mars Helicopter (MH), to understand the complexity of the flow, and identify future regions of improvement. The low density of the Martian atmosphere and the relatively small MH rotor, result in very low chord-based Reynolds…22 ppARC-E-DAA-TN50660
- Geometry and Simulation Results for a Gas Turbine Representative of the Energy Efficient Engine (EEE)This paper describes the geometry and simulation results of a gas-turbine engine based on the original EEE engine developed in the 1980s. While the EEE engine was never in production, the technology developed during the program underpins many of the current generation of gas turbine engines. This…30 ppNASA/TM-2015-218408
- Ground-based and in-flight simulator studies of low-speed handling characteristics of two supersonic cruise transport conceptsConventional and powered lift concepts for supersonic approach and landing tasks are considered. Results indicated that the transport concepts had unacceptable low-speed handling qualities with no augmentation, and that in order to achieve satisfactory handling qualities, considerable augmentation…. The publisher removed this document from its site; this copy is preserved from the Internet Archive.103 pp19780019168
- Ground-run tests with a bogie landing gear in water and slushGround-run tests with bogie-type landing gear on water and slush covered runways52 ppNASA-TN-D-3515
- Ground-to-Flight Handling Qualities Comparisons for a High Performance AirplaneA flight test program was conducted in conjunction with a ground-based piloted simulation study to enable a comparison of handling qualities ratings for a variety of maneuvers between flight and simulation of a modern high performance airplane. Specific objectives included an evaluation of…24 pp19970005147
- Guide for Pressure-Sensitive Paint Testing at NASA Ames Research Center Unitary Plan Wind TunnelOptical measurement techniques have become a standard option for wind tunnel tests. Pressure-sensitive paint (PSP) is a mature test technique and a common experimental technique in many wind tunnels to measure the global mean static pressure on a model. PSP is a valuable tool when a more detailed…11 ppARC-E-DAA-TN77197
- Hamiltonian Gust Load Alleviation Control with Adaptive Gust Estimation: Analysis and Wind Tunnel Test CorrelationThis paper presents the design and experimental validation of a Hamiltonian controller for gust load alleviation (GLA) on a flexible wing wind tunnel model. The control design incorporates practical implementation considerations, including low-pass filtering to prevent excitation of high-frequency…15 pp
- Handling qualities and structural characteristics of the hingeless-rotor helicopterSeveral advantages and potential problem areas associated with the hingeless-rotor helicopter are discussed. The extent to which two of the advantages - increased control and damping moments - can be obtained with the hingeless-rotor helicopter is established. The upper limit on the available…
- Handling qualities aspects of NASA YF-12 flight experienceThe handling qualities of the YF-12 airplane as observed during NASA research flights over the past five years were reviewed. Aircraft behavior during takeoff, acceleration, climb, cruise, descent, and landing are discussed. Pilot comments on the various flight phases and tasks are presented.…21 pp19770011063
- Handling Qualities Evaluations of Low Complexity Model Reference Adaptive Controllers for Reduced Pitch and Roll Damping ScenariosNational Aeronautics and Space Administration (NASA) researchers have conducted a series of flight experiments designed to study the effects of varying levels of adaptive controller complexity on the performance and handling qualities of an aircraft under various simulated failure or damage…19 pp20110023802
- Handling Qualities Implications for Crewed Spacecraft OperationsAbstract Handling qualities embody those qualities or characteristics of an aircraft that govern the ease and precision with which a pilot is able to perform the tasks required in support of an aircraft role. These same qualities are as critical, if not more so, in the operation of spacecraft. A…20 pp20120003520
- Handling Qualities Influences on Civil Tiltrotor Terminal Operating Procedure DevelopmentThe potential for tiltrotor aircraft as civil transports has been well recognized. Realization of that potential requires development of operating procedures tailored to take advantage of the tiltrotor's capabilities, including thrust vectoring independent of body pitch attitude and good low-speed…8 pp20020002849
- Handling qualities of a wide-body transport airplane utilizing Pitch Active Control Systems (PACS) for relaxed static stability applicationPiloted simulation studies have been conducted to evaluate the effectiveness of two pitch active control systems (PACS) on the flying qualities of a wide-body transport airplane when operating at negative static margins. These two pitch active control systems consisted of a simple 'near-term' PACS…108 pp19880005605
- Handling Qualities of Large Flexible AircraftThe effects on handling qualities of elastic modes interaction with the rigid body dynamics of a large flexible aircraft are studied by a mathematical computer simulation. An analytical method to predict the pilot ratings when there is a severe modes interactions is developed. This is done by…74 pp19800023894
- Handling qualities of large flexible control-configured aircraftThe approach to an analytical study of flexible airplane longitudinal handling qualities was to parametrically vary the natural frequencies of two symmetric elastic modes to induce mode interactions with the rigid body dynamics. Since the structure of the pilot model was unknown for such dynamic…11 pp19790016862
- Handling qualities of large flexible control-configured aircraftThe effects on handling qualities of low frequency symmetric elastic mode interaction with the rigid body dynamics of a large flexible aircraft was analyzed by use of a mathematical pilot modeling computer simulation. An extension of the optimal control model for a human pilot was made so that the…14 pp19800016849
- Handling Qualities of Large Rotorcraft in Hover and Low SpeedAccording to a number of system studies, large capacity advanced rotorcraft with a capability of high cruise speeds (approx.350 mph) as well as vertical and/or short take-off and landing (V/STOL) flight could alleviate anticipated air transportation capacity issues by making use of non-primary…140 pp20150006816
- Handling Qualities of Model Reference Adaptive Controllers with Varying Complexity for Pitch-Roll Coupled FailuresThree model reference adaptive controllers (MRAC) with varying levels of complexity were evaluated on a high performance jet aircraft and compared along with a baseline nonlinear dynamic inversion controller. The handling qualities and performance of the controllers were examined during failure…42 pp20110015953
- Handling qualities of the High Speed Civil TransportThe low speed handling qualities of a High Speed Civil Transport class aircraft have been investigated by using data of the former Advanced Supersonic Transport (AST) 105. The operation of such vehicles in the airport terminal area is characterized by 'backside' performance. Main objectives of this…1 pp19950016905
- Handling qualities of the XB-70 airplane in the landing approachApproach and landing performance of XB-70 aircraft67 pp19700010499
- Handling Qualities Optimization for Rotorcraft Conceptual DesignOver the past decade, NASA, under a succession of rotary-wing programs has been moving towards coupling multiple discipline analyses to evaluate rotorcraft conceptual designs. Handling qualities is one of the component analyses to be included in such a future Multidisciplinary Analysis and…24 pp20180008704
- Handling Qualities Optimization for Rotorcraft Conceptual DesignOver the past decade, NASA, under a succession of rotary-wing programs has been moving towards coupling multiple discipline analyses in a rigorous consistent manner to evaluate rotorcraft conceptual designs. Handling qualities is one of the component analyses to be included in a future NASA…16 pp20160013392
- Handling Qualities Prediction of an F-16XL-Based Reduced Sonic Boom AircraftA major goal of the Supersonics Project under NASA s Fundamental Aeronautics program is sonic boom reduction of supersonic aircraft. An important part of this effort is development and validation of sonic boom prediction tools used in aircraft design. NASA Dryden s F- 16XL was selected as a…1 pp20100036540
- Handling qualities requirements for control configured vehiclesThe potential effects of fly by wire and control configured vehicle concepts on flying qualities are considered. Failure mode probabilities and consequences, controllability, and dynamics of highly augmented aircraft are among the factors discussed in terms of design criteria.12 pp19760024077
- Helicopter Acoustics, part 2Exterior and interior helicopter noise problems are addressed from the physics and engineering as well as the human factors point of view. Noise regulation concepts, human factors and criteria, rotor noise generation and control, design, operations and testing for noise control, helicopter noise…453 ppNASA-CP-2052-PT-2
- Helicopter far-field acoustic levels as a function of reduced main-rotor advancing blade-tip Mach numberDuring the design of a helicopter, the weight, engine, rotor speed, and rotor geometry are given significant attention when considering the specific operations for which the helicopter will be used. However, the noise radiated from the helicopter and its relationship to the design variables is…32 ppNASA-TM-102684
- Helicopter Handling QualitiesHelicopters are used by the military and civilian communities for a variety of tasks and must be capable of operating in poor weather conditions and at night. Accompanying extended helicopter operations is a significant increase in pilot workload and a need for better handling qualities. An…255 pp19820015334
- Helicopter main-rotor speed effects on far-field acoustic levelsThe design of a helicopter is based on an understanding of many parameters and their interactions. For example, in the design stage of a helicopter, the weight, engine, and rotor speed must be considered along with the rotor geometry when considering helicopter operations. However, the relationship…20 ppNASA-TM-100512
- Helicopter mathematical models and control law development for handling qualities researchProgress made in joint NASA/Army research concerning rotorcraft flight-dynamics modeling, design methodologies for rotorcraft flight-control laws, and rotorcraft parameter identification is reviewed. Research into these interactive disciplines is needed to develop the analytical tools necessary to…63 pp19880007259
- Helicopter noise regulations: An industry perspectiveA review of helicopter noise measurement programs and noise reduction/economic studies of FAA is given along with a critique of a study which addresses the economic impact of noise reduction on helicopter noise. Modification of several helicopters to reduce noise and demonstrate the economic impact…16 pp
- Helicopter Rotor Blade Computation in Unsteady Flows Using Moving Overset GridsAn overset grid thin-layer Navier-Stokes code has been extended to include dynamic motion of helicopter rotor blades through relative grid motion. The unsteady flowfield and airloads on an AH-IG rotor in forward flight were computed to verify the methodology and to demonstrate the method's…8 ppNASA/TM-96-207307
- Helicopter rotor noise due to ingestion of atmospheric turbulenceA theoretical study was conducted to develop an analytical prediction method for helicopter main rotor noise due to the ingestion of atmospheric turbulence. This study incorporates an atmospheric turbulence model, a rotor mean flow contraction model and a rapid distortion turbulence model which…155 ppNASA-CR-3973
- Helicopter rotor noise, part 2 Final report, 1 Dec. 1965 - 30 Nov. 1968Experimental study of helicopter rotor noise42 ppNASA-CR-66868
- Helicopter rotor noise. Part 1 - Theoretical investigation of rotational noise Final reportHelicopter rotational rotor noise theories and computation of blade loading spectra36 ppNASA-CR-66870
- Helicopter rotor trailing edge noiseA two dimensional section of a helicopter main rotor blade was tested in an acoustic wind tunnel at close to full-scale Reynolds numbers to obtain boundary layer data and acoustic data for use in developing an acoustic scaling law and testing a first principles trailing edge noise theory. Results…150 ppNASA-CR-3470
- Helicopter tail rotor blade-vortex interaction noiseA study is made of helicopter tail rotor noise, particularly that due to the interactions with main rotor tip vortices. Summarized here are present analysis, the computer codes, and the results of several test cases. Amiet's unsteady thin airfoil theory is used to calculate the acoustics of…28 ppNASA-CR-183178
- Helicopter tail rotor noise analysesA study was made of helicopter tail rotor noise, particularly that due to interactions with the main rotor tip vortices, and with the fuselage separation mean wake. The tail rotor blade-main rotor tip vortex interaction is modelled as an airfoil of infinite span cutting through a moving vortex. The…66 ppNASA-CR-176829
- Helicopter testing in a wind tunnelWind tunnel testing of helicopters, and test program for Polish helicopter industry9 pp
- Hexacopter Flight Dynamics on Earth and Martian SurfacesSince the atmospheric conditions and gravitational field are different for Mars and Earth, the operating flight environments are different, and necessitate Earth-based appropriate modeling, analysis, and simulation for Mars flight vehicles. This paper compares a hexacopter’s flight dynamics in the…13 pp
- High angle-of-attack stability-and-control analysisMethods of linear systems analysis were applied to mathematical models of aircraft flying at high angle of attack and maneuver rate. First order longitudinal and lateral directional coupling is obtained by linearizing the complete nonlinear equations of motion about a generalized (quasi steady)…14 pp
- High lift aerodynamicsThe current program is aimed at providing a physical picture of the flow physics and quantitative turbulence data of the interaction of a high Reynolds number wake with a flap element. The impact of high lift on aircraft performance is studied for a 150 passenger transport aircraft with the goal of…48 pp19940020786
- High Lift Common Research Model for Wind Tunnel Testing: An Active Flow Control PerspectiveThis paper provides an overview of a research and development effort sponsored by the NASA Advanced Air Transport Technology Project to achieve the required high-lift performance using active flow control (AFC) on simple hinged flaps while reducing the cruise drag associated with the external…15 pp20170001029
- High lift wake investigationThe behavior of wakes in adverse pressure gradients is critical to the performance of high-lift systems for transport aircraft. Wake deceleration is known to lead to sudden thickening and the onset of reversed flow; this 'wake bursting' phenomenon can occur while surface flows remain attached.…15 pp19960016681
- High performance forward swept wing aircraftA high performance aircraft capable of subsonic, transonic and supersonic speeds employs a forward swept wing planform and at least one first and second solution ejector located on the inboard section of the wing. A high degree of flow control on the inboard sections of the wing is achieved along…13 pp19880019530
- High Pressure Regenerative Turbine Engine: 21st Century PropulsionA novel semi-closed cycle gas turbine engine was demonstrated and was found to meet the program goals. The proof-of-principle test of the High Pressure Regenerative Turbine Engine produced data that agreed well with models, enabling more confidence in designing future prototypes based on this…147 pp20010026758
- High Reynolds number test of a NACA 651-213, a equals 0.5 airfoil at transonic speedsWind-Tunnel tests were conducted in the Lockheed-Georgia Company's compressible flow facility to determine the transonic two-dimensional aerodynamic characteristics of a NACA 65 sub 1-213 a = 0.50 airfoil. The results are correlated with data obtained in the NASA-Langley 8-foot transonic pressure…165 ppNASA-CR-2499
- High Reynolds number transonic tests on a NACA 0012 airfoil in the Langley 0.3-meter transonic cryogenic tunnelTests were conducted in the two-dimensional test section of the Langley 0.3-m Transonic Cryogenic Tunnel on a NACA 0012 airfoil to obtain aerodynamic data as a part of the Advanced Technology Airfoil Test (ATAT) program. The test program covered a Mach number range of 0.30 to 0.82 and a Reynolds…150 ppNASA-TM-100527
- High Stability Engine Control (HISTEC) Flight Test ResultsThe High Stability Engine Control (HISTEC) Program, managed and funded by the NASA Lewis Research Center, is a cooperative effort between NASA and Pratt & Whitney (P&W). The program objective is to develop and flight demonstrate an advanced high stability integrated engine control system that uses…14 ppNASA/TM-1998-208481
- High temperature turbine engine structureA high temperature ceramic/metallic turbine engine includes a metallic housing which journals a rotor member of the turbine engine. A ceramic disk-like shroud portion of the engine is supported on the metallic housing portion and maintains a close running clearance with the rotor member. A ceramic…9 ppPatent Application Number: US-PATENT-APPL-SN-439991
- High temperature turbine engine structureA high temperature turbine engine includes a hybrid ceramic/metallic rotor member having ceramic/metal joint structure. The disclosed joint is able to endure higher temperatures than previously possible, and aids in controlling heat transfer in the rotor member.7 ppPatent Application Number: US-Patent-Appl-SN-280761
- High temperature turbine engine structureA high temperature turbine engine includes a rotor portion having axially stacked adjacent ceramic rotor parts. A ceramic/ceramic joint structure transmits torque between the rotor parts while maintaining coaxial alignment and axially spaced mutually parallel relation thereof despite thermal and…8 ppPatent Application Number: US-PATENT-APPL-SN-282786
- High temperature turbine engine structureA high temperature ceramic/metallic turbine engine includes a metallic housing which journals a rotor member of the turbine engine. A ceramic disk-like shroud portion of the engine is supported on the metallic housing portion and maintains a close running clearance with the rotor member. A ceramic…9 ppPatent Application Number: US-PATENT-APPL-SN-843874
- High temperature turbine engine structureA high temperature ceramic/metallic turbine engine includes a metallic housing which journals a rotor member of the turbine engine. A ceramic disk-like shroud portion of the engine is supported on the metallic housing portion and maintains a close running clearance with the rotor member. A ceramic…9 ppPatent Application Number: US-PATENT-APPL-SN-842870
- High-Alpha Handling Qualities Flight Research on the NASA F/A-18 High Alpha Research VehicleA flight research study of high-angle-of-attack handling qualities has been conducted at the NASA Dryden Flight Research Center using the F/A-18 High Alpha Research Vehicle (HARV). The objectives were to create a high-angle-of-attack handling qualities flight database, develop appropriate research…40 pp19970001693
- High-energy fuels for supersonic transport reservesHigh energy fuels for supersonic transport reserves37 ppNASA-TN-D-3987
- High-Lift Optimization Design Using Neural Networks on a Multi-Element AirfoilThe high-lift performance of a multi-element airfoil was optimized by using neural-net predictions that were trained using a computational data set. The numerical data was generated using a two-dimensional, incompressible, Navier-Stokes algorithm with the Spalart-Allmaras turbulence model. Because…10 pp20020060751
- High-Lift Propeller System Configuration Selection for NASA's SCEPTOR Distributed Electric Propulsion Flight DemonstratorAlthough the primary function of propellers is typically to produce thrust, aircraft equipped with distributed electric propulsion (DEP) may utilize propellers whose main purpose is to act as a form of high-lift device. These \high-lift propellers" can be placed upstream of wing such that, when the…19 pp20160010105
- High-speed T-38A landing gear extension loadsTesting of T-38A landing gear extension at high speed and high altitude is described. The mechanisms are shown together with peak hydraulic pressure data during landing gear deployment with active and inactive strut door flaps. Results of strain gage measurements of stress on various structural…22 ppNASA-TM-58226
- High-Speed Wind Tunnel Tests of a Full-Scale Proprotor on the Tiltrotor Test RigThe Tiltrotor Test Rig (TTR) is a NASA project, joint with the U.S. Army and Air Force, to develop a new, large scale proprotor test system for the National Full-Scale Aerodynamics Complex (NFAC). The first wind-tunnel entry was completed in November 2018 with a modern, 26-ft diameter proprotor.…19 ppARC-E-DAA-TN67822
- Highly integrated digital electronic control: Digital flight control, aircraft model identification, and adaptive engine controlThe highly integrated digital electronic control (HIDEC) program at NASA Ames Research Center, Dryden Flight Research Facility is a multiphase flight research program to quantify the benefits of promising integrated control systems. McDonnell Aircraft Company is the prime contractor, with United…16 pp19870014186
- Highly Maneuverable Aircraft Technology (HiMAT) flight-flutter test programThe highly maneuverable aircraft technology (HiMAT) vehicle was evaluated in a joint NASA and Air Force flight test program. The HiMAT vehicle is a remotely piloted research vehicle. Its design incorporates the use of advanced composite materials in the wings, and canards for aeroelastic tailoring.…22 pp19860017818
- Hingeless helicopter rotor with improved stabilityImproved stability was provided in a hingeless helicopter rotor by inclining the principal elastic flexural axes and coupling pitching of the rotor blade with the lead-lag bending of the blade. The primary elastic flex axes were inclined by constructing the blade of materials that display…10 ppPatent Application Number: US-PATENT-APPL-SN-513612
- Historical Overview and Recent Improvements at the NASA Glenn Research Center 8x6 9x15 Wind Tunnel ComplexA brief history of the 8x6 Supersonic Wind Tunnel (SWT) and 9x15 Low Speed Wind Tunnel (LSWT) at NASA Glenn Research Center, Cleveland, Ohio is presented along with current capabilities and plans for future upgrades within the facility.40 ppGRC-E-DAA-TN20102
- Historical overview of V/STOL aircraft technologyThe requirements for satisfactory characteristics in several key technology areas are discussed and a review is made of various V/STOL aircraft for the purpose of assessing the success or failure of each design in meeting design requirements. Special operating techniques were developed to help…20 pp19810010574
- Holographic testing of composite propfans for a cruise missile wind tunnel modelEach of the approximately 90 composite propfan blades constructed for a 55 percent scale cruise missile wind tunnel model were holographically tested to obtain natural frequencies and mode shapes. These data were used not only for quality assurance, but also to select sets of similar blades for…42 pp19940019072
- HOPE: An On-Line Piloted Handling Qualities Experiment Data BookA novel on-line database for capturing most of the information obtained during piloted handling qualities experiments (either flight or simulated) is described. The Hyperlinked Overview of Piloted Evaluations (HOPE) web application is based on an open-source object-oriented Web-based front end…12 pp20100030601
- Hot gas ingestion testing of an advanced STOVL concept in the NASA Lewis 9- by 15-foot low speed wind tunnel with flow visualizationAdvanced Short Takeoff/Vertical Landing (STOVL) aircraft capable of operating from remote sites, damaged runways, and small air capable ships are being pursued for deployment around the turn of the century. To achieve this goal, it is important that the technologies critical to this unique class of…27 pp19890005707
- Hot gas ingestion: From model results to full scale engine testingAn overview is presented of a joint NASA Lewis McDonnell Aircraft Co. Hot Gas Ingestion (HGI) test program in NASA Lewis' 9 x 15 foot Low Speed Wind Tunnel (LSWT). Advanced short takeoff vertical landing (ASTOVL) aircraft capable of operating from remote sites, damaged runways, aircraft carriers…21 pp19870014986
- Hot-bench simulation of the active flexible wing wind-tunnel modelTwo simulations, one batch and one real-time, of an aeroelastically-scaled wind-tunnel model were developed. The wind-tunnel model was a full-span, free-to-roll model of an advanced fighter concept. The batch simulation was used to generate and verify the real-time simulation and to test candidate…16 ppNASA-TM-102758
- HOVERING CHARACTERISTICS OF A ROTOR HAVING AN AIRFOIL SECTION DESIGNED FOR AUTILITY TYPE OF HELICOPTERHovering characteristics of rotor having airfoil section designed for utility type helicopter22 ppNASA-TN-D-1517
- Hovering performance characteristics of a rotor with and without blade-pitch servo-control flapsPhotographic performance evaluation of hovering helicopter rotor with and without blade pitch servocontrol flaps18 ppNASA-TN-D-3786
- How Usability Testing Resulted in Improvements to Ground Collision Software for General Aviation: Improved Ground Collision Avoidance System (IGCAS)The NASA improved Ground Collision Avoidance System (iGCAS) team conducted an onsite usability study at Experimental Aircraft Association (EAA) Air Venture in Oshkosh, Wisconsin from July 19 through July 26, 2015. EAA Air Venture had approximately 550,000 attendees from which the sample pool of…26 ppDFRC-E-DAA-TN35844
- HSCT high-lift technology requirementsThe viewgraphs and discussion of high lift needs and related aerodynamic goals established in system studies are described. The goals are presented for the takeoff, approach, and subsonic climb and cruise modes. The status of the related high lift databases and available design and analysis methods…22 pp19940029017
- Human Survival in Aircraft EmergenciesHuman survival in flight emergencies involving commercial and general aviation aircraft66 pp19690005431
- Hybrid Electric Propulsion Technologies for Commercial TransportsNASA Aeronautics Research Mission Directorate has set strategic research thrusts to address the major drivers of aviation such as growth in demand for high-speed mobility, addressing global climate and capitalizing in the convergence of technological advances. Transitioning aviation to low carbon…25 pp20170000016
- Hybrid upper surface blown flap propulsive-lift concept for the quiet short-haul research aircraftThe hybrid upper surface blowing concept consists of wing-mounted turbofan engines with a major portion of the fan exhaust directed over the wing upper surface to provide high levels of propulsive lift, but with a portion of the fan airflow directed over selected portions of the airframe to provide…11 pp19750024017
- Hybrid Wing Body Planform Design with Vehicle Sketch PadThe objective of this paper was to provide an update on NASA’s current tools for design and analysis of hybrid wing body (HWB) aircraft with an emphasis on Vehicle Sketch Pad (VSP). NASA started HWB analysis using the Flight Optimization System (FLOPS). That capability is enhanced using Phoenix…8 pp20110002876
- Hybrid-Electric and Distributed Propulsion Technologies for Large Commercial Transports: A NASA PerspectiveDevelop and demonstrate technologies that will revolutionize commercial transport aircraft propulsion and accelerate development of all-electric aircraft architectures. Enable radically different propulsion systems that can meet national environmental and fuel burn reduction goals for subsonic…35 pp20160000589
- Hyper-X (X-43A) Flight Test Range OperationsThe Hyper-X program flew X-43A research vehicles to hypersonic speeds over the Pacific Ocean in March and November 2004 from the Western Aeronautical Test Range, NASA Dryden Flight Research Center, Edwards, California. The program required multiple telemetry ground stations to provide continuous…10 pp
- Hypersonic aerodynamic problems at re-entry of space vehiclesHypersonic aerodynamic problems at space vehicle reentry - plasma effects on communications blackout, hypersonic flow, and atmospheric entry27 pp19660006323
- Hypersonic aircraft designA hypersonic aircraft is designed which uses scramjets to accelerate from Mach 6 to Mach 10 and sustain that speed for two minutes. Different propulsion systems were considered and it was decided that the aircraft would use one full scale turbofan-ramjet. Two solid rocket boosters were added to…174 pp19910003348
- Hypersonic cruise aircraft propulsion integration study, volume 1A hypersonic cruise transport conceptual design is described. The integration of the subsonic, supersonic, and hypersonic propulsion systems with the aerodynamic design of the airframe is emphasized. An evaluation of various configurations of aircraft and propulsion integration concepts, and…88 pp19800006815
- Hypersonic cruise vehicle wing structure evaluation - Volume 2, sections 11-22Structure size, weight, flutter, fatigue, creep, and heat shield analyses for hypersonic cruise vehicle wing569 pp19700017939
- Hypersonic cruise vehicle wing structure evaluation - Volume 3, sections 23-27Cost, performance, reliability, interaction, and structural element analyses for hypersonic cruise vehicle wings486 pp19700017940
- Hypersonic Vehicle Propulsion System Simplified Model DevelopmentThis document addresses the modeling task plan for the hypersonic GN&C GRC team members. The overall propulsion system modeling task plan is a multi-step process and the task plan identified in this document addresses the first steps (short term modeling goals). The procedures and tools produced…10 pp20080006063
- Icarus Rewaxed: A high speed, low-cost general aviation aircraft for AeroworldIcarus Rewaxed is a single engine, six passenger, general aviation airplane. With a cruise velocity of 72 ft/s, the Icarus can compete with the performance of any other airplane in its class with an eye on economics and safety. It has a very competitive initial price ($3498.00) and cost per flight…169 pp19950006196
- Ice Accretion Test Results for Three Large-Scale Swept-Wing Models in the NASA Icing Research TunnelThe design and certification of modern transport airplanes for flight in icing conditions increasing relies on three-dimensional numerical simulation tools for ice accretion prediction. There is currently no publically available, high-quality, ice accretion database upon which to evaluate the…26 ppGRC-E-DAA-TN32827
- Ice Accretions and Full-Scale Iced Aerodynamic Performance Data for a Two-Dimensional NACA 23012 AirfoilThis report documents the data collected during the large wind tunnel campaigns conducted as part of the SUNSET project (StUdies oN Scaling EffecTs due to ice) also known as the Ice-Accretion Aerodynamics Simulation study; a joint effort by NASA, ONERA, and the University of Illinois. These data…446 ppNASA/TP-2016-218348
- Ice Accretions and Icing Effects for Modern AirfoilsIcing tests were conducted to document ice shapes formed on three different two-dimensional airfoils and to study the effects of the accreted ice on aerodynamic performance. The models tested were representative of airfoil designs in current use for each of the commercial transport, business jet,…292 pp20000044552
- Ice Crystal Icing Engine Testing in the NASA Glenn Research Center's Propulsion Systems Laboratory (PSL): Altitude InvestigationThe National Aeronautics and Space Administration conducted a full scale ice crystal icing turbofan engine test in the NASA Glenn Research Centers Propulsion Systems Laboratory (PSL) Facility in February 2013. Honeywell Engines supplied the test article, an obsolete, unmodified Lycoming ALF502-R5…11 pp20150019751
- Ice Crystal Icing Engine Testing in the NASA Glenn Research Center's Propulsion Systems Laboratory: Altitude InvestigationThe National Aeronautics and Space Administration (NASA) conducted a full scale ice crystal icing turbofan engine test using an obsolete Allied Signal ALF502-R5 engine in the Propulsion Systems Laboratory (PSL) at NASA Glenn Research Center. The test article used was the exact engine that…7 pp20150022398
- Ice Crystal Icing Research at NASAIce crystals found at high altitude near convective clouds are known to cause jet engine power-loss events. These events occur due to ice crystals entering a propulsion systems core flowpath and accreting ice resulting in events such as uncommanded loss of thrust (rollback), engine stall, surge,…22 ppGRC-E-DAA-TN43061
- Ice Crystal Icing Research at NASAIce crystals found at high altitude near convective clouds are known to cause jet engine power-loss events. These events occur due to ice crystals entering a propulsion systems core flowpath and accreting ice resulting in events such as uncommanded loss of thrust (rollback), engine stall, surge,…19 ppGRC-E-DAA-TN42705
- Ice Particle Analysis of the Honeywell AL502 Engine BoosterA flow and ice particle trajectory analysis was performed for the booster of the Honeywell ALF502 engine. The analysis focused on two closely related conditions one of which produced an icing event and another which did not during testing of the ALF502 engine in the Propulsion Systems Lab (PSL) at…15 pp20150018407
- Ice Roughness and Thickness Evolution on a Swept NACA 0012 AirfoilSeveral recent studies have been performed in the Icing Research Tunnel (IRT) at NASA Glenn Research Center focusing on the evolution, spatial variations, and proper scaling of ice roughness on airfoils without sweep exposed to icing conditions employed in classical roughness studies. For this…17 ppGRC-E-DAA-TN42660
- Ice Shape Analysis of an eVTOL Propeller in Forward Flight at the NASA Glenn Icing Research TunnelAdvanced Air Mobility (AAM) introduces many novel electric vertical takeoff and landing (eVTOL) aircraft configurations for which the effect of icing is not well understood. While icing computational tools have often aided in the design and certification of conventional aircraft, experimental data…23 pp
- Ice Shape Analysis of an eVTOL Propeller in Forward Flight at the NASA Glenn Icing Research TunnelAdvanced Air Mobility (AAM) introduces many novel electric vertical takeoff and landing (eVTOL) aircraft configurations for which the effect of icing is not well understood. While icing computational tools have often aided in the design and certification of conventional aircraft, experimental data…23 pp
- Ice-Accretion Test Results for Three Large-Scale Swept-Wing Models in the NASA Icing Research TunnelIcing simulation tools and computational fluid dynamics codes are reaching levels of maturity such that they are being proposed by manufacturers for use in certification of aircraft for flight in icing conditions with increasingly less reliance on natural-icing flight testing and icing-wind-tunnel…30 ppGRC-E-DAA-TN31804
- Ice-Accretion Test Results for Three Large-Scale Swept-Wing Models in the NASA Icing Research TunnelIcing simulation tools and computational fluid dynamics codes are reaching levels of maturity such that they are being proposed by manufacturers for use in certification of aircraft for flight in icing conditions with increasingly less reliance on natural-icing flight testing and icing-wind-tunnel…40 ppNASA/TM-2016-219137
- Ice-Crystal Icing Accretion Studies at the NASA Propulsion Systems LaboratoryThis paper describes an ice-crystal icing experiment conducted at the NASA Propulsion System Laboratory during June 2018. This test produced ice shape data on an airfoil for different test conditions similar to those inside the compressor region of a turbo-fan jet engine. Mixed-phase icing…11 ppGRC-E-DAA-TN66895
- Icing Analysis of a Swept NACA 0012 Wing Using LEWICE3D Version 3.48Icing calculations were performed for a NACA 0012 swept wing tip using LEWICE3D Version 3.48 coupled with the ANSYS CFX flow solver. The calculated ice shapes were compared to experimental data generated in the NASA Glenn Icing Research Tunnel (IRT). The IRT tests were designed to test the…24 ppGRC-E-DAA-TN15558
- Icing Analysis of a Swept NACA 0012 Wing Using LEWICE3D Version 3.48Icing calculations were performed for a NACA 0012 swept wing tip using LEWICE3D Version 3.48 coupled with the ANSYS CFX flow solver. The calculated ice shapes were compared to experimental data generated in the NASA Glenn Icing Research Tunnel (IRT). The IRT tests were designed to test the…37 ppGRC-E-DAA-TN15312
- Icing and De-Icing of a Propeller with Internal Electric Blade HeatersAn investigation has been made in the NACA Cleveland icing research tunnel to determine the de-icing effectiveness of an experimental configuration of an Internal electric propeller-blade heater. Two atmospheric Icing conditions and two propeller operating conditions were Investigated, In…52 pp19810068617
- Icing effects on aircraft stability and control determined from flight data: Preliminary resultsThe effects of airframe icing on the stability and control characteristics of the NASA DH-6 Twin Otter icing research aircraft were investigated by flight test. The flight program was developed to obtain the stability and control parameters of the DH-6 in a baseline ('uniced') configuration and an…29 ppNASA-TM-105977
- Icing flight research: Aerodynamic effects of ice and ice shape documentation with stereo photographyAircraft icing flight research was performed in natural icing conditions. A data base consisting of icing cloud measurements, ice shapes, and aerodynamic measurements is being developed. During research icing encounters the icing cloud was continuously measured. After the encounter, the ice…33 pp19850009740
- Icing Frequencies Experienced During Climb and Descent by Fighter-Interceptor AircraftData and analyses are presented on the relative frequencies of occurrence and severity of icing cloud layers encountered by jet aircraft in the climb and descent phases of flights to high altitudes. Fighter-interceptor aircraft operated by the Air Defense Command (USAF) at bases in the Duluth and…31 ppNACA-TN-4314
- Icing Physics Studies Using the 3D SIDRM Test Article: 2023 Icing Tests AnalysisIn-flight icing is an important safety issue and is a factor that affects aircraft design and performance. Newer regulations are driving a need for improvements in airframe and engine icing simulation capability. Experimental data are required for the development of icing physics models and…76 ppNASA/CR-20260000820
- Icing Physics Studies Using the 3D SIDRM Test Article: Aerodynamic and Supercooled Liquid Icing AnalysisIn-flight icing is an important safety issue and is a factor that affects aircraft design and performance. Newer regulations are driving a need for improvements in airframe and engine icing simulation capability. Experimental data is required for development of icing physics models and simulation…20 pp
- Icing Physics Studies Using the 3D SIDRM Test Article: Aerodynamic and Supercooled Liquid Icing AnalysisIn-flight icing is an important safety issue and is a factor that affects aircraft design and performance. Newer regulations are driving a need for improvements in airframe and engine icing simulation capability. Experimental data is required for development of icing physics models and simulation…13 pp
- Icing Physics Studies Using the 3D SIDRM Test Article: Ice Crystal Icing AnalysisIn-flight icing is an important safety issue and is a factor that affects aircraft design and performance. Newer regulations are driving a need for improvements in airframe and engine icing simulation capability. Experimental data is required for the development of icing physics models and…25 pp
- Icing Physics Studies Using the 3D SIDRM Test Article: Ice Crystal Icing AnalysisIn-flight icing is an important safety issue and is a factor that affects aircraft design and performance. Newer regulations are driving a need for improvements in airframe and engine icing simulation capability. Experimental data is required for the development of icing physics models and…31 pp
- Icing Protection for a Turbojet Transport Airplane: Heating Requirements, Methods of Protection, and Performance PenaltiesThe problems associated with providing icing protection for the critical components of a typical turbojet transport airplane operating over a range of probable icing conditions are analyzed and discussed. Heating requirements for several thermal methods of protection are evaluated and the airplane…61 pp19810068606
- Icing Sensor ProbeAircraft icing is a serious safety problem for the general aviation and some commuter transport airplanes. There has been tremendous growth in the commuter aviation industry in the last few years, Since these type of aircraft generally operate at lower altitudes they consequently spend a far…15 ppNASA/TM-2002-211368
- Icing Simulation Research Supporting the Ice-Accretion Testing of Large-Scale Swept-Wing ModelsThe work summarized in this report is a continuation of NASA's Large-Scale, Swept-Wing Test Articles Fabrication; Research and Test Support for NASA IRT contract (NNC10BA05 -NNC14TA36T) performed by Boeing under the NASA Research and Technology for Aerospace Propulsion Systems (RTAPS) contract. In…72 pp20180002545
- Icing simulation: A survey of computer models and experimental facilitiesA survey of the current methods for simulation of the response of an aircraft or aircraft subsystem to an icing encounter is presented. The topics discussed include a computer code modeling of aircraft icing and performance degradation, an evaluation of experimental facility simulation…30 pp19910013774
- Icing testing in the large Modane wind-tunnel on full-scale and reduced scale modelsIcing tests on full scale models of parts of aircraft (wings, tailplanes, radome) equipped with actual de-icing systems were carried out in the large Modane wind tunnel of ONERA. For studying icing on the Concorde, it was necessary to use a 1/6 scale half model. The equations governing the relevant…20 pp19790011931
- Icing: Accretion, Detection, ProtectionThe global aircraft industry and its regulatory agencies are currently involved in three major icing efforts: ground icing; advanced technologies for in-flight icing; and tailplane icing. These three major icing topics correspondingly support the three major segments of any aircraft flight profile:…27 ppE-9139
- Impact of Advanced Propeller Technology on Aircraft/Mission Characteristics of Several General Aviation AircraftStudies of several General Aviation aircraft indicated that the application of advanced technologies to General Aviation propellers can reduce fuel consumption in future aircraft by a significant amount. Propeller blade weight reductions achieved through the use of composites, propeller efficiency…82 pp19820025471
- Impact of General Aviation Operations on Airport Performance Through Fast-Time Simulations at Charlotte Douglas International AirportNASA, in partnership with the Federal Aviation Administration and commercial airlines, deployed the Integrated Arrival, Departure, and Surface (IADS) traffic management system at Charlotte Douglas International Airport (CLT) in 2017 for field evaluation. The system features new capabilities of data…12 pp
- Impingement of Water Droplets on an NACA 65(sub 1) -212 Airfoil at an Angle of Attack of 4 DegThe trajectories of droplets in the air flowing past an NACA 651-212 airfoil at an angle of attack of 40 were determined. The collection efficiency, the area of droplet impingement, and the rate of droplet impingement were calculated from the trajectories and are presented herein.49 ppNACA-RM-E52B12
- Impingement of water droplets on NACA 65(1)-208 and 65(1)-212 airfoils at 4 degrees angle of attackThe trajectories of droplets in the air flowing past NACA 65(1)-208 airfoil and an NACA 65(1)-212 airfoil, both at an angle of attack of 4 degrees, were determined. The amount of water in droplet form impinging on the airfoils, the area of droplet impingement, and the rate of droplet impingement…50 ppNACA-TN-2952
- Impingement of Water Droplets on NACA 65A004 Airfoil and Effect of Change in Airfoil Thickness from 12 to 4 Percent at 4 deg Angle of AttackThe trajectories of droplets in the air flowing past an NACA 65A004 a irfoil at an angle of attack of 4 deg were determined. The amount of water in droplet form impinging on the airfoil, the area of droplet impingement, and the rate of droplet impingement per unit area on the airfoil surface were…46 ppNACA-TN-3047
- Impingement of Water Droplets on NACA 65A004 Airfoil at 0 Deg Angle of AttackThe trajectories of water droplets in the air flowing past an NACA 6511004 airfoil at a n angle of attack of 0 deg were determined. The amount of water in droplet form impinging on the airfoil , the area of droplet impingement, and the rate of droplet impingement per unit area on the airfoil…29 ppNACA-TN-3586
- Impingement of Water Droplets on NACA 65A004 Airfoil at 8 deg Angle of AttackThe trajectories of droplets in the air flowing past an NACA 65AO04 airfoil at an angle of attack of 8 deg were determined.. The amount of water in droplet form impinging on the airfoil, the area of droplet impingement, and the rate of droplet impingement per unit area on the airfoil surface were…28 ppNACA-TN-3155
- Implementation and Evaluation of Multiple Adaptive Control Technologies for a Generic Transport Aircraft SimulationPresented here is the evaluation of multiple adaptive control technologies for a generic transport aircraft simulation. For this study, seven model reference adaptive control (MRAC) based technologies were considered. Each technology was integrated into an identical dynamic-inversion control…17 ppARC-E-DAA-TN1569
- Implications of Contingency Planning Support for Weather and Icing InformationA human-centered systems analysis was applied to the adverse aircraft weather encounter problem in order to identify desirable functions of weather and icing information. The importance of contingency planning was identified as emerging from a system safety design methodology as well as from…9 ppSAE-2003-01-2089
- Implications of control technology on aircraft designNew controls technologies are now available for implementation with aircraft systems. Many aircraft with state of the art technology in the fields of aerodynamics, structures, and propulsion require extensive augmentation merely for safety of flight considerations in addition to potential…22 pp
- Improved Lunar Lander Handling Qualities Through Control Response Type and Display EnhancementsA piloted simulation that studied the handling qualities for a precision lunar landing task from final approach to touchdown is presented. A vehicle model based on NASA's Altair Lunar Lander was used to explore the design space around the nominal vehicle configuration to determine which combination…19 pp20100039179
- Improved Mars Helicopter Aerodynamic Rotor Model for Comprehensive AnalysesThe Mars Helicopter is part of the NASA Mars 2020 rover mission scheduled to launch in July of 2020. Its goal is to demonstrate the viability and potential of heavier-than-air vehicles in the Martian atmosphere. Ultimately, it aims to bridge the resolution gap between orbiters and the rover as well…14 ppERF Paper No. 2018-28
- Improving Large-Scale Testing Capability by Modifying the 40- by 80-ft Wind TunnelInteragency studies conducted during the last several years have indicated the need to Improve full-scale testing capabilities. The studies showed that the most effective trade between test capability and facility cost was provided by re-powering the existing Ames Research Center 40- by 80-ft Wind…6 pp19990026257
- In Flight Evaluation of Active Inceptor Force-Feel Characteristics and Handling QualitiesThe effect of inceptor feel-system characteristics on piloted handling qualities has been a research topic of interest for many years. Most of the research efforts have focused on advanced fly-by-wire fixed-wing aircraft with only a few studies investigating the effects on rotorcraft. Consequently,…18 pp20120011852
- In-flight evaluation of the lateral handling of a four-engine jet transport during approach and landingFlight evaluation of lateral handling, stability, control, and flying qualities of jet transport aircraft during up-and-away and approach flight in landing configuration33 pp19710016061
- In-flight measurements of wing ice shapes and wing section drag increases caused by natural icing conditionsAircraft icing flight research was performed in natural icing conditions with a twin engine computer type STOL aircraft. In-flight measurements were made of the icing cloud environment, the shape of the ice accretion on the wing, and the corresponding increase in the wing section drag. Results are…28 pp19860015196
- In-flight pilot evaluations of the flying qualities of a four-engine jet transportThe flying qualities of the CV-990 jet transport were evaluated over the normal operating flight envelope and in smooth air to provide baseline data for transport airplanes. Pilot ratings of airplane handling characteristics for specific test conditions and configurations from approach to normal…55 pp19720014376
- In-Flight Stability Analysis of the X-48B AircraftThis report presents the system description, methods, and sample results of the in-flight stability analysis for the X-48B, Blended Wing Body Low-Speed Vehicle. The X-48B vehicle is a dynamically scaled, remotely piloted vehicle developed to investigate the low-speed control characteristics of a…10 ppDFRC-775
- In-Flight Vibration Environment of the NASA F-15B Flight Test FixtureFlight vibration data are analyzed for the NASA F-15B/Flight Test Fixture II test bed. Understanding the in-flight vibration environment benefits design and integration of experiments on the test bed. The power spectral density (PSD) of accelerometer flight data is analyzed to quantify the…31 pp20020043372
- Incorporating Data Link Messaging into a Multi-function Display for General Aviation AircraftOne objective of the Small Aircraft Transportation System (SATS) Project is to increase the capacity and utilization of small non-towered, non-radar equipped airports by transferring traffic management activities to an automated system and separation responsibilities to general aviation (GA)…9 pp20080014107
- Incorporating Handling Qualities Analysis into Rotorcraft Conceptual DesignThis paper describes the initial development of a framework to incorporate handling qualities analyses into a rotorcraft conceptual design process. In particular, the paper describes how rotorcraft conceptual design level data can be used to generate flight dynamics models for handling qualities…23 pp20140013447
- Increased Fidelity in Prediction Methods For Landing Gear NoiseAn aeroacoustic prediction scheme has been developed for landing gear noise. The method is designed to handle the complex landing gear geometry of current and future aircraft. The gear is represented by a collection of subassemblies and simple components that are modeled using acoustic elements.…13 pp
- Inertial Force Coupling to Nonlinear Aeroelasticity of Flexible Wing AircraftThis paper investigates the inertial force effect on nonlinear aeroelasticity of flexible wing aircraft. The geometric are nonlinearity due to rotational and tension stiffening. The effect of large bending deflection will also be investigated. Flutter analysis will be conducted for a truss-braced…19 pp20160007397
- Inerting Aircraft Fuel Systems Using Exhaust GasesOur purpose in this proposal was to determine the feasibility of using carbon dioxide, possibly obtained from aircraft exhaust gases as a substance to inert the fuel contained in fuel tanks aboard aircraft. To do this, we decided to look at the effects carbon dioxide has upon commercial Jet-A…5 pp20020051190
- Inflight and ground-based simulation of handling qualities of very large airplanes in landing approachInflight and ground based simulation of Boeing 367-80 variable stability aircraft handling qualities during landing approach60 pp19660029515
- INFLUENCE OF AUTOMATIC CONTROL OF ROLL COUPLING AND PITCH-UP ON TAIL LOADSStability & control of aircraft - aerodynamic loading24 ppNACA-RM-L57D18A
- Initial Assessment of a Variable-Camber Continuous Trailing-Edge Flap System on a Rigid Wing for Drag Reduction in Subsonic CruiseIn this paper, we describe an initial optimization study of a Variable-Camber Continuous Trailing-Edge Flap (VCCTEF) system. The VCCTEF provides a light-weight control system for aircraft with long flexible wings, providing efficient high-lift capability for takeoff and landing, and greater…22 pp20140008924
- Initial Flight Test of the Production Support Flight Control Computers at NASA Dryden Flight Research CenterThe NASA Dryden Flight Research Center has completed the initial flight test of a modified set of F/A-18 flight control computers that gives the aircraft a research control law capability. The production support flight control computers (PSFCC) provide an increased capability for flight research in…19 pp19990060322
- Initial Low-Reynolds Number Iced Aerodynamic Performance for CRM WingNASA, FAA, ONERA, and other partner organizations have embarked on a significant, collaborative research effort to address the technical challenges associated with icing on large scale, three-dimensional swept wings. These are extremely complex phenomena important to the design, certification and…23 ppGRC-E-DAA-TN23444
- Initial report on operational experiences of general aviation aircraftGust and maneuver acceleration fractions, and flight loads for light aircraft50 pp19680013846
- Initial Results from Radiometer and Polarized Radar-Based Icing Algorithms Compared to In-Situ DataIn early 2015, a field campaign was conducted at the NASA Glenn Research Center in Cleveland, Ohio, USA. The purpose of the campaign is to test several prototype algorithms meant to detect the location and severity of in-flight icing (or icing aloft, as opposed to ground icing) within the terminal…7 ppGRC-E-DAA-TN22909
- Initiation of Turbulent Spots in a Laminar Boundary Layer by Rigid Falling ParticulatesA transitional laminar boundary layer is developed on a 1m wide km long flat plate in a 0.6m deep water channel with a freestream velocity of 15-50 cm/s. A particulate dispenser under computer control ejects individual particles having diameters of 1/3 delta into the free stream. The particulates…8 pp20070038951
- Inlet Performance of the NFAC 1/50th-scale 80- by 120- Foot Wind TunnelThe National Full-Scale Aerodynamics Complex 80- by 120-Foot Wind Tunnel (80x120) was dedicated in 1987 and rated at 100 knots for full-scale aircraft testing at NASA Ames Research Center. The 80x120 is the world’s largest wind tunnel, designed as an open circuit tunnel with a large aerodynamically…12 pp
- Inlet sensitivity study for a supersonic transportMethod of comparing inlet performance and weight compromises for supersonic transport35 ppNASA-TN-D-3881
- Inlet-to-inlet shock interference tests final reportExperimental test program and wind tunnel test data obtained during inlet to inlet shock interference tests57 ppNASA-CR-264
- Innovative Flow Control Concepts for Drag ReductionThis paper highlights the technology development of two flow control concepts for aircraft drag reduction. The NASA Environmentally Responsible Aviation (ERA) project worked with Boeing to demonstrate these two concepts on a specially outfitted Boeing 757 ecoDemonstrator during the spring of 2015.…16 pp20160007668
- Input design for identification of aircraft stability and control derivativesAn approach for designing inputs to identify stability and control derivatives from flight test data is presented. This approach is based on finding inputs which provide the maximum possible accuracy of derivative estimates. Two techniques of input specification are implemented for this objective -…142 ppNASA-CR-2493
- Instability Wave-Streak Interactions in a Supersonic Boundary LayerOptimal initial conditions for transient growth in a two-dimensional boundary layer flow correspond to stationary, counter-rotating vortices that subsequently develop into streamwise elongated streaks, which are characterized by an alternating pattern of low and high streamwise velocity. For…24 pp20190027633
- Installation drag considerations as related to turboprop and turbofan enginesSome of the specific areas associated with straight jet and turboprop engine installations are outlined where drag reduction and, thus, improved aircraft system performance is obtained. Specific areas constitute air intake sizing for general aviation aircraft, exhaust duct geometries and cooling…12 pp19760003927
- Integrated Aerodynamic and Control System Design of Oblique Wing AircraftAn efficient high speed aircraft design must achieve a high lift to drag ratio at transonic and supersonic speeds. In 1952 Dr. R. T. Jones proved that for any flight Mach number minimum drag at a fixed lift is achieved by an elliptic wing planform with an appropriate oblique sweep angle. Since…274 ppNASA-CR-192614
- Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project-longitudinal handling qualities study of a relaxed-stability airplaneThe results of a piloted simulation of longitudinal handling qualities of an airplane with relaxed static stability are described. This task was performed under the Integrated Application of Active Controls (IAAC) Technology Project within the NASA Energy Efficient Transport Program. A…70 pp19850002697
- Integrated Approach to the Dynamics and Control of Maneuvering Flexible AircraftThis work uses a fundamental approach to the problem of simulating the flight of flexible aircraft. To this end, it integrates into a single formulation the pertinent disciplines, namely, analytical dynamics, structural dynamics, aerodynamics, and controls. It considers both the rigid body motions…76 ppNASA/CR-2003-211748
- Integrated control and display research for transition and vertical flight on the NASA V/STOL Research Aircraft (VSRA)Results of a substantial body of ground-based simulation experiments indicate that a high degree of precision of operation for recovery aboard small ships in heavy seas and low visibility with acceptable levels of effort by the pilot can be achieved by integrating the aircraft flight and propulsion…34 ppNASA-TM-100029
- Integrated Control Using the SOFFT Control StructureThe need for integrated/constrained control systems has become clearer as advanced aircraft introduced new coupled subsystems such as new propulsion subsystems with thrust vectoring and new aerodynamic designs. In this study, we develop an integrated control design methodology which accomodates…102 ppNASA-CR-4748
- Integrated Control with Structural Feedback to Enable Lightweight AircraftThis presentation for the Fundamental Aeronautics Program Technical Conference covers the benefits of active structural control, related research areas, and focuses on the use of optimal control allocation for the prevention of critical loads. Active control of lightweight structures has the…29 ppDFRC-E-DAA-TN3199
- Integrated Flight and Propulsion Controls for Advanced Aircraft ConfigurationsThe research vision of the NASA Lewis Research Center in the area of integrated flight and propulsion controls technologies is described. In particular the Integrated Method for Propulsion and Airframe Controls developed at the Lewis Research Center is described including its application to an…10 pp19960003390
- Integrated Flight Propulsion Control Research Results Using the NASA F-15 HIDEC Flight Research FacilityOver the last two decades, NASA has conducted several flight research experiments in integrated flight-propulsion control. Benefits have included increased thrust, range, and survivability; reduced fuel consumption; and reduced maintenance. These flight programs were flown at NASA Dryden Flight…19 ppAIAA-92-4106
- Integrated gas turbine engine-nacelleA nacelle for use with a gas turbine engine is presented. An integral webbed structure resembling a spoked wheel for rigidly interconnecting the nacelle and engine, provides lightweight support. The inner surface of the nacelle defines the outer limits of the engine motive fluid flow annulus while…9 ppPatent Number: NASA-CASE-LEW-12389-2
- Integrated gas turbine engine-nacelleA nacelle for use with a gas turbine engine is provided with an integral webbed structure resembling a spoked wheel for rigidly interconnecting the nacelle and engine. The nacelle is entirely supported in its spacial relationship with the engine by means of the webbed structure. The inner surface…9 ppPatent Application Number: US-PATENT-APPL-SN-552108
- Integrated Model Reduction and Control of Aircraft with Flexible WingsThis paper presents an integrated approach to the modeling and control of aircraft with exible wings. The coupled aircraft rigid body dynamics with a high-order elastic wing model can be represented in a nite dimensional state-space form. Given a set of desired output covariance, a model reduction…22 ppARC-E-DAA-TN10408
- Integrated research aircraft control technology with full authority digital electronic controlBaseline definitions for three major areas of the Integrated Research Aircraft Control Technology (INTERACT) program are provided.118 ppNASA-CR-163100
- Integrated Resilient Aircraft Control Project Full Scale Flight ValidationObjective: Provide validation of adaptive control law concepts through full scale flight evaluation. Technical Approach: a) Engage failure mode - destabilizing or frozen surface. b) Perform formation flight and air-to-air tracking tasks. Evaluate adaptive algorithm: a) Stability metrics. b) Model…10 ppDFRC-1045
- Integrated Test and Evaluation (ITE) Flight Test Series 4The integrated Flight Test 4 (FT4) will gather data for the UAS researchers Sense and Avoid systems (referred to as Detect and Avoid in the RTCA SC 228 ToR) algorithms and pilot displays for candidate UAS systems in a relevant environment. The technical goals of FT4 are to: 1) perform end-to-end…332 ppDFRC-E-DAA-TN39175
- Integrated Turbine Tip Clearance and Gas Turbine Engine SimulationGas turbine compressor and turbine blade tip clearance (i.e., the radial distance between the blade tip of an axial compressor or turbine and the containment structure) is a major contributing factor to gas path sealing, and can significantly affect engine efficiency and operational temperature.…24 ppNASA/TM-2016-219146
- Integrated Turbine Tip Clearance and Gas Turbine Engine SimulationGas turbine compressor and turbine blade tip clearance (i.e., the radial distance between the blade tip of an axial compressor or turbine and the containment structure) is a major contributing factor to gas path sealing, and can significantly affect engine efficiency and operational temperature.…16 ppGRC-E-DAA-TN33215
- Integrating Flight Dynamics & Control Analysis and Simulation in Rotorcraft Conceptual DesignThe development of a toolset, SIMPLI-FLYD ('SIMPLIfied FLight dynamics for conceptual Design') is described. SIMPLI-FLYD is a collection of tools that perform flight dynamics and control modeling and analysis of rotorcraft conceptual designs including a capability to evaluate the designs in an…18 ppARC-E-DAA-TN31729
- Integration of dynamic, aerodynamic, and structural optimization of helicopter rotor bladesSummarized here is the first six years of research into the integration of structural, dynamic, and aerodynamic considerations in the design-optimization process for rotor blades. Specifically discussed here is the application of design optimization techniques for helicopter rotor blades. The…22 ppNASA-CR-189018
- Intelligent Control Approaches for Aircraft ApplicationsThis paper presents an overview of various intelligent control technologies currently being developed and studied under the Intelligent Flight Control (IFC) program at the NASA Ames Research Center. The main objective of the intelligent flight control program is to develop the next generation of…9 pp
- Intelligent Control for Drag Reduction on the X-48B VehicleThis paper focuses on the development of an intelligent control technology for in-flight drag reduction. The system is integrated with and demonstrated on the full X-48B nonlinear simulation. The intelligent control system utilizes a peak-seeking control method implemented with a time-varying…28 pp20110015999
- Interactive aircraft flight control and aeroelastic stabilizationAn analytical model of a 3-D airfoil was used to study an optimization procedure formulated to enhance stability of an airfoil through integrated structural and control synthesis. This procedure is discussed together with preliminary results. These results show that a sensitivity derivative…21 ppNASA-CR-176035
- Interactive aircraft flight control and aeroelastic stabilizationAeroservoelastic optimization techniques were studied to determine a methodology for maximization of the stable flight envelope of an idealized, actively controlled, flexible airfoil. The equations of motion for the airfoil were developed in state-space form to include time-domain representations…49 ppNASA-CR-176323
- Interactive aircraft flight control and aeroelastic stabilizationThe potential benefits and costs of optimizing both the structural stiffness and the active control of aircraft in a rational manner are investigated. The ultimate goal is to arrive at a unified treatment of structural and active control design for the stability augmentation of flexible aircraft.…14 ppNASA-CR-173866
- Interagency aircraft noise abatement programNational program for aircraft noise reduction4 pp
- Interior noise considerations for powered-lift STOL aircraftPowered-jet configuration which are under development for use on STOL aircraft involve impingement of the jet engine exhaust onto wing and flap surfaces. The impinging jet produces higher noise levels at lower frequencies than does the jet alone. These higher levels, together with the close…19 pp19750011176
- Interior noise levels of two propeller-driven light aircraftThe relationships between aircraft operating conditions and interior noise and the degree to which ground testing can be used in lieu of flight testing for performing interior noise research were studied. The results show that the noise inside light aircraft is strongly influenced by the rotational…25 pp19750019994
- Introduction to Aircraft Icing and NASA's Approach to Understanding ItThis presentation provides an introduction to aircraft icing and describes NASA’s approach to understanding it. The presentation covers various topics on icing. A general overview of different types of icing is provided, which includes airframe icing, jet engine icing, and rotorcraft icing. The…63 pp
- Introduction to Computational Methods for Stability and Control (COMSAC)This Symposium is intended to bring together the often distinct cultures of the Stability and Control (S&C) community and the Computational Fluid Dynamics (CFD) community. The COMSAC program is itself a new effort by NASA Langley to accelerate the application of high end CFD methodologies to the…21 pp
- Introduction to the aerodynamics of flightGeneral concepts of the aerodynamics of flight are discussed. Topics considered include: the atmosphere; fluid flow; subsonic flow effects; transonic flow; supersonic flow; aircraft performance; and stability and control.212 pp19760003955
- Introduction to the Glenn Icing Computational Environment (GlennICE)The NASA John H. Glenn Research Center at Lewis Field is developing the Glenn Icing Computational Environment (GlennICE) tool to aid those evaluating, designing and certifying aircraft, engines, and aircraft components for flight in icing conditions. This short course will walk through some of the…64 pp
- Investigation of a Spoiler-Type Lateral Control System on a Wing with Full-Span Flaps in the Langley 19-Foot Pressure TunnelTests of a partial-span model of a large bomber-type air1ane were conducted to determine the. aerodynamic characteristics of the wing equipped with full-span flaps and a retractable spoiler end aileron lateral control system. The arrangement consisted of (1) a double slotted flap extending over…54 ppNACA-TN-1409
- Investigation of a Tandem Tilt-wing VTOL Aircraft in the NASA Langley 12-Foot Low-Speed TunnelThe emerging Urban Air Mobility market imposes new design requirements on aircraft, including the ability to have vertical take-off and landing (VTOL) capabilities with the ability to transition into fast and efficient forward flight. Industry has proposed many different vehicle configurations,…343 pp
- Investigation of a Technique for Measuring Dynamic Ground Effect in a Subsonic Wind TunnelTo better understand the ground effect encountered by slender wing supersonic transport aircraft, a test was conducted at NASA Langley Research Center's 14 x 22 foot Subsonic Wind Tunnel in October, 1997. Emphasis was placed on improving the accuracy of the ground effect data by using a "dynamic"…66 ppNASA/CR-1999-209544
- Investigation of aerodynamic characteristics of an airplane configuration having tail surfaces outboard of the wing tips at Mach numbers of 2.30, 2.97, and 3.51Aerodynamic characteristics of aircraft configuration having tail surfaces outboard of wing tips at supersonic speeds - wind tunnel stability test50 ppNACA-RM-L58C25
- INVESTIGATION OF BOUNDARY LAYER PARAMETERS IN APG NOZZLE AND THE FLOW INTERFERENCE CAUSED BY SECONDARY INJECTIONFlow interference caused by secondary injection in adverse pressure gradient nozzles - boundary layer parameter investigations268 pp19630010059
- Investigation of Control System and Display Variations on Spacecraft Handling Qualities for Docking with Stationary and Rotating TargetsThis paper documents the investigation into the manual docking of a preliminary version of the Crew Exploration Vehicle with stationary and rotating targets in Low Earth Orbit. The investigation was conducted at NASA Langley Research Center in the summer of 2008 in a repurposed fixed-base transport…126 pp20100008933
- Investigation of correlation between full-scale and fifth-scale wind tunnel tests of a Bell helicopter Textron Model 222Reasons for lack of correlation between data from a fifth-scale wind tunnel test of the Bell Helicopter Textron Model 222 and a full-scale test of the model 222 prototype in the NASA Ames 40-by 80-foot tunnel were investigated. This investigation centered around a carefully designed fifth-scale…402 ppNASA-CR-166362
- Investigation of Diving Moments of a Pursuit Airplane in the Ames 16-Foot High Speed Wind TunnelA pursuit type airplane encountered severe diving moments in high-speed dives which make recovery difficult. For the purpose of investigating these diving moments and finding means for their reduction, a 1/6-scale model of the airplane was tested in the 16-foot high-speed wind tunnel at Ames…86 ppNACA-WR-A-65
- Investigation of dynamic characteristics of a turbine-propeller engineTime constants that characterize engine speed response of a turbine-propeller engine over the cruising speed range for various values of constant fuel flow and constant blade angle were obtained both from steady-state characteristics and from transient operation. Magnitude of speed response to…23 ppNACA-RM-E51F15
- Investigation of Extreme Leading-Edge Roughness on Thick Low-Drag Airfoils to Indicate Those Critical to SeparationSeveral airfoils, Including a conventional NACA 23021 and some low-drag airfoils for which the thickness had been increased to the point that they were considered doubtfully conservative with respect to separation, were investigated as smooth airfoils and after the application of a standard…17 ppNACA-WR-L-659
- Investigation of Flight Test Methods for measuring the performance of general aviation aircraftA theoretical and experimental investigation of methods for measuring the performance of general aviation airplanes was conducted using relatively simple instrumentation currently available and data extraction techniques established from efforts in other disciplines. The possibilities of improving…18 pp19810011537
- Investigation of level-flight and maneuvering characteristics of a hingeless-rotor compound helicopterFlight tests on hingeless rotor compound helicopter to determine level flight and maneuvering characteristics34 ppNASA-TN-D-5602
- Investigation of long term exposure effects under stress on supersonic transport structural materials Phase I report, Jun. 1963 - Jul. 1964Long term exposure effects under stress on supersonic transport structural materials98 ppNASA-CR-80489
- Investigation of long-term exposure effects under stress on supersonic transport structural alloysLong term exposure effects under stress on supersonic transport structural materials - titanium alloys, steels, and superalloys103 ppNASA-CR-76151
- Investigation of pitch maneuver speed margins for a supersonic transport configuration with a variable-sweep wingFlight simulator study of pitch maneuver speed margins for variable-sweep wing supersonic transport configuration17 ppNASA-TN-D-4170
- Investigation of spoiler ailerons for use as speed brakes or glide-path controls on two NACA 65-series wings equipped with full-span slotted flapsA wind-tunnel investigation was made to determine the characteristics of spoiler ailerons used as speed brakes or glide-path controls on an NACA 65-210 wing and an NACA 65-215 wing equipped with full-span slotted flaps. Several plug aileron and retractable-aileron configurations were investigated…30 ppNACA-TR-1034
- Investigation of the free-flight characteristics and handling qualities of a ground-effect machineFree flight characteristics and handling qualities of ground effect machine - Gem III stability28 pp19670013535
- Investigation of the NACA 4-(3)(8)-045 Two-blade Propellers at Forward Mach Numbers to 0.725 to Determine the Effects of Compressibility and Solidity on PerformanceAs part of a general investigation of propellers at high forward speeds, tests of two 2-blade propellers having the NACA 4-(3)(8)-03 and NACA 4-(3)(8)-45 blade designs have been made in the Langley 8-foot high-speed tunnel through a range of blade angle from 20 degrees to 60 degrees for forward…37 ppNACA-TR-999
- Investigation of Turbulence Generated by Upwind Blockages at the Inlet of a 1/50th-Scale Model of the 80- by 120-Foot Wind TunnelA 1/50th scale model of the 80- by 120-Foot Wind Tunnel (hereafter referred to as the 80x120) was utilized to determine the magnitude of turbulence caused by buildings located upstream of the wind tunnel inlet. The 1/50th scale models of existing and proposed buildings were constructed to act as…903 ppNASA/CR-2018-219908
- Investigations of Shuttle Main Landing Gear Door Environmental SealsThe environmental seals for the main landing gear doors of the Shuttle Orbiters were raised by the Columbia Accident Investigation Board as a potential safety concern. Inspections of seals installed on the Shuttle Discovery revealed that they were permanently deformed and no longer met certified…25 ppNASA/TM-2005-213860
- Isokinetic TWC Evaporator Probe: Development of the IKP2 and Performance Testing for the HAIC-HIWC Darwin 2014 and Cayenne 2015 Field CampaignsA new Isokinetic Total Water Content Evaporator (IKP2) was downsized from a prototype instrument, specifically to make airborne measurements of hydrometeor total water content (TWC) in deep tropical convective clouds to assess the new ice crystal Appendix D icing envelope. The probe underwent…28 pp20170000243
- Isokinetic TWC Evaporator Probe: Development of the IKP2 and Performance Testing for the HAIC-HIWC Darwin 2014 and Cayenne-2015 Field CampaignsA new Isokinetic Total Water Content Evaporator (IKP2) was downsized from a prototype instrument, specifically to make airborne measurements of hydrometeor total water content (TWC) in deep tropical convective clouds to assess the new ice crystal Appendix D icing envelope. The probe underwent…42 pp20160013859
- It's time to reinvent the general aviation airplaneCurrent designs for general aviation airplanes have become obsolete, and avenues for major redesign must be considered. New designs should incorporate recent advances in electronics, aerodynamics, structures, materials, and propulsion. Future airplanes should be optimized to operate satisfactorily…25 pp
- Jet aircraft engine noise reductionThe development of advanced technology to reduce the effects of aircraft flyover noise is described. The procedures are directed toward identifying and minimizing the noise sources in aircraft engines and to absorbing noises which cannot be eliminated. The economic impact resulting from reducing…11 ppNASA-TM-X-68131
- Jet Engine hot parts IR Analysis Procedure (J-EIRP)A thermal radiation analysis method called Jet Engine IR Analysis Procedure (J-EIRP) was developed to evaluate jet engine cavity hot parts source radiation. The objectives behind J-EIRP were to achieve the greatest accuracy in model representation and solution, while minimizing computer resources…22 ppNASA-TM-105914
- Jet engine performance enhancement through use of a wave-rotor topping cycleA simple model is used to calculate the thermal efficiency and specific power of simple jet engines and jet engines with a wave-rotor topping cycle. The performance of the wave rotor is based on measurements from a previous experiment. Applied to the case of an aircraft flying at Mach 0.8, the…14 ppNASA-TM-4486
- JT8D engine performance retentionThe attractive performance retention characteristics of the JT8D engine are described. Because of its moderate bypass ratio and turbine temperature, and stiff structural design, the performance retention versus flight cycles of the JT8D engine sets a standard that is difficult for other engines to…20 pp19810022658
- JT9D jet engine diagnostics programPerformance deterioration in the JT9D-7 is a flight sensitive phenomenon caused by one short term and two long term wear modes. The short term deterioration occurs primarily during airplane acceptance testing and therefore does not affect airline operation. The long term wear takes place…20 pp
- JT9D jet engine performance deteriorationThe analytical techniques utilized to examine the effects of flight loads and engine operating conditions on performance deterioration are presented. The role of gyroscopic, gravitational, and aerodynamic loads are shown along with the effect of variations in engine build clearances. These…14 pp
- JT9D-7A (SP) jet engine performance deterioration trendsThe levels, trends, and causes of engine performance deterioration were investigated. A series of installed engine calibrations (both on-the-ground and in-flight) were performed on two new Pan American World Airways 747 SP aircraft. The performance data gathered covered from before the first flight…24 ppNASA-TM-81459
- Judgment tests of aircraft noisePsychological tests of human responses to aircraft noise levels14 pp
- Key Topics for High-Lift Research: A Joint Wind Tunnel/Flight Test ApproachFuture high-lift systems must achieve improved aerodynamic performance with simpler designs that involve fewer elements and reduced maintenance costs. To expeditiously achieve this, reliable CFD design tools are required. The development of useful CFD-based design tools for high lift systems…30 ppNASA-CR-202525
- Knowledge-based processing for aircraft flight controlThe purpose is to develop algorithms and architectures for embedding artificial intelligence in aircraft guidance and control systems. With the approach adopted, AI-computing is used to create an outer guidance loop for driving the usual aircraft autopilot. That is, a symbolic processor monitors…8 ppNASA-CR-194074
- Landing dynamics study for lunar landing research vehicleImpact dynamics and effects on lunar landing module performance and landing gear73 ppNASA-CR-428
- Landing Energy Dissipation for Manned Reentry VehiclesAnalytical and experimental investigations have been made to determine the landing-energy-dissipation characteristics for several types of landing gear for manned reentry vehicles. The landing vehicles are considered in two categories: those having essentially vertical-descent paths, the…18 ppNASA-TN-D-453
- Landing gear and cavity noise predictionPrediction of airframe noise radiation from the landing gear and wheel wells of commercial aircraft is examined. Measurements of these components on typical aircraft are presented and potential noise sources identified. Semiempirical expressions for the sound generation by these sources are…58 ppNASA-CR-2714
- Landing Gear Components Noise Study - PIV and Hot-Wire MeasurementsPIV and hot-wire measurements of the wake flow from rods and bars are presented. The test models include rods of different diameters and cross sections and a rod juxtaposed to a plate. The latter is representative of the latch door that is attached to an aircraft landing gear when the gear is…53 ppNASA/TM-2010-216209
- Landing Gear Door Liners for Airframe Noise ReductionA landing gear door for retractable landing gear of aircraft includes an acoustic liner. The acoustic liner includes one or more internal cavities or chambers having one or more openings that inhibit the generation of sound at the surface and/or absorb sound generated during operation of the…10 ppPatent Application Number: US-Patent-Appl-SN-13/417,349
- Landing gear energy absorption systemA landing pad system is described for absorbing horizontal and vertical impact forces upon engagement with a landing surface where circumferentially arranged landing struts respectively have a clevis which receives a slidable rod member and where the upper portion of a slidable rod member is…7 ppPatent Number: NASA-CASE-MSC-22277-1
- Landing Gear Integration in Aircraft Conceptual DesignThe design of the landing gear is one of the more fundamental aspects of aircraft design. The design and integration process encompasses numerous engineering disciplines, e.g., structure, weights, runway design, and economics, and has become extremely sophisticated in the last few decades. Although…194 pp19970031272
- Landing gear noise attenuationA landing gear noise attenuator mitigates noise generated by airframe deployable landing gear. The noise attenuator can have a first position when the landing gear is in its deployed or down position, and a second position when the landing gear is in its up or stowed position. The noise attenuator…44 ppPatent Application Number: US-Patent-Appl-SN-10/599,495
- Landing Gear Noise Prediction and Analysis for Tube-and-Wing and Hybrid-Wing-Body AircraftImprovements and extensions to landing gear noise prediction methods are developed. New features include installation effects such as reflection from the aircraft, gear truck angle effect, local flow calculation at the landing gear locations, gear size effect, and directivity for various gear…25 ppNF1676L-21517
- Landing gear PatentVertically descending flight vehicle landing gear for rough terrain7 ppPatent Number: NASA-CASE-XMF-01174
- LANDING LOADS AND DYNAMICS OF THE X-15 AIRPLANEMeasurements of loads, accelerations, and displacements of x-15 aircraft and landing gear during landing impact18 ppNASA-TM-X-639
- Landing practices of general aviation pilots in single-engine light airplanesThe methods and techniques used by a group of general aviation pilots during the landing phase of light airplane operations are documented. The results of 616 landings made by 22 pilots in 2 modern, four-place, single-engine, flight airplanes (one having a low wing and the other, a high wing) are…53 pp19770004090
- LANDING-GEAR BEHAVIOR DURING TOUCHDOWN AND RUNOUT FOR 17 LANDINGS OF THE X-15 RESEARCH AIRPLANELanding gear behavior during touchdown of x-15 aircraft54 ppNASA-TM-X-518
- Landing-gear impactReport deals with the impact forces in landing gears. Both the landing impact and the taxiing impact have been considered, but drag forces have so far been excluded. The differential equations are developed and their numerical integration is shown, considering the nonlinear properties of the oleo…92 ppNACA-TN-2743
- Langley Aircraft Landing Dynamics FacilityThe Langley Research Center has recently upgraded the Landing Loads Track (LLT) to improve the capability of low-cost testing of conventional and advanced landing gear systems. The unique feature of the Langley Aircraft Landing Dynamics Facility (ALDF) is the ability to test aircraft landing gear…35 pp19870020111
- Langley airfoil-research programAn overview of past, present, and future airfoil research activities at the Langley Research Center is given. The immediate past and future occupy most of the discussion; however, past accomplishments and milestones going back to the early NACA years are dealt with in a broad-brush way to give a…27 pp19790011861
- LANN wing designThe LANN wing is the result of a joint effort between Lockheed, the Air Force, NASA, and the Netherlands to measure unsteady pressures at transonic speeds. It is a moderate-aspect-ratio transport wing configuration. The wing was machined from NITRONIC 40 and has 12 percent thick supercritical…3 pp19830010484
- Large aircraft handling qualitiesThe short period frequency requirements of MIL-F-8785C are applicable to the very large transport aircraft simulated. The large aircraft simulated meet the requirements of NASA CR-159236 for effective time delay and pitch transient peak ratio. However, the requirements of this reference for the…14 pp19840012502
- Large size cryogenic turbine type flowmeter technologyProcurement, calibration, installation, and use of cryogenic turbine flowmeters for M-1 engine50 ppNASA-CR-54810
- Large-scale Advanced Prop-fan (LAP) high speed wind tunnel test reportHigh Speed Wind Tunnel testing of the SR-7L Large Scale Advanced Prop-Fan (LAP) is reported. The LAP is a 2.74 meter (9.0 ft) diameter, 8-bladed tractor type rated for 4475 KW (6000 SHP) at 1698 rpm. It was designated and built by Hamilton Standard under contract to the NASA Lewis Research Center.…216 ppNASA-CR-182125
- Large-Scale Boundary Layer Ingesting Propulsor ResearchNASA’s Advanced Air Transport Technology (AATT) project is investigating boundary layer ingesting (BLI) propulsors for advanced subsonic commercial vehicle concepts to enable the reduction of fuel burn. A multidisciplinary team of researchers from NASA, United Technologies Research Center (UTRC),…12 pp20190031845
- Large-scale low-speed wind-tunnel tests of a delta winged supersonic transport model to determine aerodynamic effects of forward or reverse thrustLarge scale low speed wind tunnel tests of delta winged supersonic transport model to determine aerodynamic effects of forward and reverse thrust35 pp19670022812
- Large-scale V/STOL testingSeveral facets of large-scale testing of V/STOL aircraft configurations are discussed with particular emphasis on test experience in the Ames 40- by 80-Foot Wind Tunnel. Examples of powered-lift test programs are presented in order to illustrate tradeoffs confronting the planner of V/STOL test…16 pp19770016147
- Large-scale wind-tunnel investigation of the low-speed aerodynamic characteristics of a supersonic transport model having variable- sweep wingsLarge scale wind tunnel investigation of low speed aerodynamic characteristics of supersonic transport model having variable sweep wings127 ppNASA-TN-D-2824
- Large-scale wind-tunnel tests of an airplane model with an unswept tilt wing of aspect ratio of 5.5, and with various stall control devicesWind-tunnel stability tests of tilt-wing vtol aircraft44 ppNASA-TN-D-2133
- Large-scale wind-tunnel tests of descent performance of an airplane model with a tilt wing and differential propeller thrustWind tunnel tests of wing stall, performance, and longitudinal stability & control of large model v/stol tilt wing transport aircraft46 ppNASA-TN-D-1857
- Large-scale wind-tunnel tests of inverting flaps on a STOL utility aircraft modelA unique inverting flap system was investigated on a large scale deflected slipstream model in the Ames 40 by 80 foot wind tunnel. The subject tests utilized 33% chord double-slotted flaps on a low aspect ratio wing that was fully immersed in the propeller slipstream. Evaluation of the flap…58 ppNASA-TP-1696
- Late Stage Hypersonic Boundary Layer TransitionOur knowledge of late-stage hypersonic boundary layer transition is very limited, since most theoretical and experimental work has concentrated on the linear disturbance amplification regime. Although experiments show linear higher harmonics beginning at approximately one-half the transition…13 pp20070038948
- Lateral and longitudinal aerodynamic stability and control parameters of the basic vortex flap research aircraft as determined from flight test dataThe aerodynamics of the basic F-106B were determined at selected points in the flight envelope. The test aircraft and flight procedures were presented. Aircraft instrumentation and the data system were discussed. The parameter extraction procedure was presented along with a discussion of the test…40 ppNASA-TM-87711
- Lateral ride quality of the B-1 aircraft subjected to a reduction of lateral static stabilityA method to evaluate the lateral ride quality of a B-1 aircraft subjected to a reduction in lateral static stability is developed. Ride quality is then found for three different relaxed static stability configurations which are augmented by yaw rate feedback to restore specified handling qualities.…18 pp19760019100
- Lateral-directional control of the x-15 airplaneLateral directional control and stability characteristics of X-15 aircraft27 ppNASA-TM-X-726
- Lateral-directional stability and control characteristics of the Quiet Short-Haul Research Aircraft (QSRA)The results are presented of flight experiments to determine the lateral-directional stability and control characteristics of the Quiet Short-Haul Research Aircraft (QSRA), an experimental aircraft designed to furnish information on various aerodynamic characteristics of a transport type of…38 ppNASA-TM-102250
- Learjet model 25 drag analysisProcedures and data for estimating drag were used to calculate the drag characteristics of the Model 25 airplane. Based on cruise flight test data obtained on the Model 25, these methods generally predicted the total drag characteristics within current acceptable and reasonable engineering accuracy.11 pp19760003936
- Learn-To-Fly Project Overview: In-Flight and Wind Tunnel Global Nonlinear Aerodynamic ModelingSummary of near real time modeling techniques applied to flight tests and wind tunnel tests.31 pp20200007715
- Lessons from Modeling Flexible Aircraft for Active Flutter SuppressionThese slides describe a method and technology of modeling flexible aircraft for active control of structural dynamics. Objective: Generate models useful for the design and evaluation of control laws for active structural control and flutter suppression that are able to accurately predict body…27 pp20190002087
- Lewis icing research tunnel test of the aerodynamic effects of aircraft ground deicing/anti-icing fluidsA wind tunnel investigation of the effect of aircraft ground deicing/anti-icing fluids on the aerodynamic characteristics of a Boeing 737-200ADV airplane was conducted. The test was carried out in the NASA Lewis Icing Research Tunnel. Fluids tested include a Newtonian deicing fluid, three…136 ppNASA-TP-3238
- Lift and Drag of a Swept-Wing Fighter Airplane at Transonic and Supersonic SpeedsA flight investigation was made of the lift and drag of a sweptwing fighter airplane in the basic configuration and in a slats-locked-closed configuration over a Mach number range from about 0.63 to about 1.44. At a nominal lift coefficient of 0.1 negligible drag-coefficient difference existed…32 pp19630004009
- Lift enhancing tabs for airfoilsA tab deployable from the trailing edge of a main airfoil element forces flow onto a following airfoil element, such as a flap, to keep the flow attached and thus enhance lift. For aircraft wings with high lift systems that include leading edge slats, the slats may also be provided with tabs to…9 pp19950016975
- Lift/cruise fan V/STOL technology aircraft design definition study. Volume 2: Propulsion transmission system designTwo types of lift/cruise fan technology aircraft were conceptually designed. One aircraft used turbotip fans pneumatically interconnected to three gas generators, and the other aircraft used variable pitch fans mechanically interconnected to three turboshaft engines. The components of each…61 pp19770009071
- Lifting surface theory for a helicopter rotor in forward flightA lifting surface theory was developed for a helicopter rotor in forward flight for compressible and incompressible flow. The method utilizes the concept of the linearized acceleration potential and makes use of the vortex lattice procedure. Calculations demonstrating the application of the method…16 ppNASA-TM-86315
- Lifting surface theory for a helicopter rotor in forward flightA lifting surface theory was developed for a helicopter rotor in forward flight for compressible and incompressible flow. The method utilizes the concept of the linearized acceleration potential and makes use of the vortex lattice procedure. Calculations demonstrating the application of the method…13 pp
- Light aircraft lift, drag, and moment prediction: A review and analysisThe historical development of analytical methods for predicting the lift, drag, and pitching moment of complete light aircraft configurations in cruising flight is reviewed. Theoretical methods, based in part on techniques described in the literature and in part on original work, are developed.…500 pp19750016605
- Light transport and general aviation aircraft icing research requirementsA short term and a long term icing research and technology program plan was drafted for NASA LeRC based on 33 separate research items. The specific items listed resulted from a comprehensive literature search, organized and assisted by a computer management file and an industry/Government agency…347 ppNASA-CR-165290
- Lightning damage to a general aviation aircraft: Description and analysisThe damage sustained by a Beechcraft King Air Model B90 aircraft by a single lightning discharge is presented and analyzed. The incident occurred during landing approach at Jackson, Michigan, on Feb. 19, 1971. In addition to the usual melted-metal damage at the lightning attachment points, there…54 pp19740025337
- Lightning Hazards to Aircraft Fuel TanksThe hazards of lightning strokes to aircraft fuel tanks have been investigated in artificial-lightning-generation facilities specifically constructed to duplicate closely the natural lightning discharges to air craft determined through flight research programs and analysis of lightning-damaged…59 pp19930085198
- Lightplane Wing DesignVenture, a kit airplane designed and manufactured by Questair, is a high performance lightplane with excellent low speed characteristics and enhanced safety due to NASA technology incorporated in its unusual wing design. In 1987, North Carolina State graduate students and Langley Research Center…1 pp20020083305
- Lightweight diesel aircraft engines for general aviationTwo different engines were studied. The advantages of a diesel to general aviation were reduced to fuel consumption, reduced operating costs, and reduced fire and explosion hazard. There were no ignition mixture control or inlet icing problems. There are fewer controls and no electrical…9 pp19830014184
- Lightweight diesel aircraft engines for general aviationA methodical design study was conducted to arrive at new diesel engine configurations and applicable advanced technologies. Two engines are discussed and the description of each engine includes concept drawings. A performance analysis, stress and weight prediction, and a cost study were also…39 pp19800013851
- Lightweight, Efficient Power Converters for Advanced Turboelectric Aircraft Propulsion SystemsNASA is investigating advanced turboelectric aircraft propulsion systems that use superconducting motors to drive multiple distributed turbofans. Conventional electric motors are too large and heavy to be practical for this application; therefore, superconducting motors are required. In order to…1 pp20150005309
- Linearized Poststall Aerodynamic and Control Law Models of the X-31A Aircraft and Comparison with Flight DataThe X-31A aircraft has a unique configuration that uses thrust-vector vanes and aerodynamic control effectors to provide an operating envelope to a maximum 70 deg angle of attack, an inherently nonlinear portion of the flight envelope. This report presents linearized versions of the X-31A…65 ppNASA/TM-97-206318
- Linearized Theory of Wind-tunnel Jet-boundary Corrections and Ground Effect for VTOL-STOL AircraftA linearized theory is developed to obtain interference factors for wind tunnels and ground effect. The calculated results, presented in tabular form in NASA Technical Notes D-933, D-934, D-935, and D-936, indicate that the degree to which the wake is deflected downward has a primary effect on the…286 ppNASA-TR-R-124
- Local Flow Effects on Noise Prediction of Transonic Truss-Braced Wing Landing GearThe local flow velocity is a primary scaling parameter to the strength of noise sources on landing gear. Airframe geometry, particularly the landing gear integration details can result in large, localized deviations from the freestream velocity. The transonic truss-braced wing aircraft concept…18 pp
- Longitudinal aerodynamic characteristics at Mach numbers from 0.50 to 1.19 of a supersonic transport model with a modified M wingLongitudinal aerodynamic characteristics at Mach numbers 0.50 to 1.19 of supersonic transport model with modified M wing74 ppNASA-TM-X-1386
- Longitudinal handling qualities during approach and landing of a powered lift STOL aircraftLongitudinal handling qualities evaluations were conducted on the Ames Research Center Flight Simulator for Advanced Aircraft (FSAA) for the approach and landing tasks of a powered lift STOL research aircraft. The test vehicle was a C-8A aircraft modified with a new wing incorporating internal…72 pp19770026207
- Longitudinal Handling Qualities of the Tu-144LL Airplane and Comparisons With Other Large, Supersonic AircraftFour flights have been conducted using the Tu-144LL supersonic transport aircraft with the dedicated objective of collecting quantitative data and qualitative pilot comments. These data are compared with the following longitudinal flying qualities criteria: Neal-Smith, short-period damping, time…44 pp20000052206
- Longitudinal stability and control characteristics of a powered model of a twin-propeller deflected-slipstream STOL AIRPLANE configurationLongitudinal stability and control characteristics of powered model of twin-propeller deflected-slipstream STOL aircraft configuration143 ppNASA-TN-D-3438
- Longitudinal stability and control characteristics of the Quiet Short-Haul Research Aircraft (QSRA)Flight experiments were conducted to evaluate various aerodynamic characteristics of the Quiet Short-Haul Research Aircraft (QSRA), an experimental aircraft that makes use of the upper-surface blown (USB) powered-lift concept. Time-history records from maneuvers performed with the aircraft in…42 ppNASA-TP-2965
- Longitudinal stability and control derivatives obtained from flight data of a PA-30 aircraftIn order to obtain reliable and accurate values of the stability and control derivatives, the Dryden Fligh Research Center (DFRC) developed a technique for extracting the derivatives from flight data. This technique is implemented by a set of FORTRAN computer programs that is based on a modified…59 ppNASA-CR-176999
- LONGITUDINAL STABILITY AND CONTROL OF A TILT-WING VTOL AIRCRAFT WITH RIGID AND FLAPPING PROPELLER BLADESLongitudinal stability and control of a tilt-wing vtol aircraft model with rigid and flapping propeller blades22 ppNASA-TN-D-1365
- Longitudinal-control design approach for high-angle-of-attack aircraftThis paper describes a control synthesis methodology that emphasizes a variable-gain output feedback technique that is applied to the longitudinal channel of a high-angle-of-attack aircraft. The aircraft is a modified F/A-18 aircraft with thrust-vectored controls. The flight regime covers a range…34 ppNASA-TP-3302
- Low Density Supersonic Decelerator (LDSD) Supersonic Flight Dynamics Test (SFDT) Plume Induced Environment ModellingProvide plume induced heating (radiation & convection) predictions in support of the LDSD thermal design (pre-flight SFDT-1) Predict plume induced aerodynamics in support of flight dynamics, to achieve targeted freestream conditions to test supersonic deceleration technologies (post-flight SFDT-1,…1 ppM16-5363
- Low speed propellers: Impact of advanced technologiesSensitivity studies performed to evaluate the potential of several advanced technological elements on propeller performance, noise, weight, and cost for general aviation aircraft are discussed. Studies indicate that the application of advanced technologies to general aviation propellers can reduce…18 pp19800013855
- Low Speed Wind Tunnel Tests on a One-Seventh Scale Model of the H.126 Jet Flap AircraftLow speed wind tunnel tests were performed on a one-seventh scale model of the British H.126 jet flap research aircraft over a range of jet momentum coefficients. The primary objective was to compare model aerodynamic characteristics with those of the aircraft, with the intent to provide…42 ppNASA-TM-X-62433
- Low subsonic flight and force investigation of a supersonic transport model with a highly swept arrow wingLow subsonic flight and force testing of supersonic transport model with highly swept arrow wing52 ppNASA-TN-D-3887
- Low-Cost Quality Control and Nondestructive Evaluation Technologies for General Aviation StructuresNASA's Advanced General Aviation Transport Experiments (AGATE) Program has as a goal to reduce the overall cost of producing private aviation aircraft while maintaining the safety of these aircraft. In order to successfully meet this goal, it is necessary to develop nondestructive inspection…14 ppNASA/TM-1998-208456
- Low-cost single-crystal turbine blades, volume 2The overall objectives of Project 3 were to develop the exothermic casting process to produce uncooled single-crystal (SC) HP turbine blades in MAR-M 247 and higher strength derivative alloys and to validate the materials process and components through extensive mechanical property testing, rig…63 ppNASA-CR-174652
- Low-Noise Potential of Advanced Fan Stage Stator Vane Designs Verified in NASA Lewis Wind Tunnel TestWith the advent of new, more stringent noise regulations in the next century, aircraft engine manufacturers are investigating new technologies to make the current generation of aircraft engines as well as the next generation of advanced engines quieter without sacrificing operating performance. A…3 pp
- Low-order nonlinear dynamic model of IC engine-variable pitch propeller system for general aviation aircraftThis paper presents a dynamic model of an internal combustion engine coupled to a variable pitch propeller. The low-order, nonlinear time-dependent model is useful for simulating the propulsion system of general aviation single-engine light aircraft. This model is suitable for investigating engine…38 pp19950026495
- Low-profile landing-gear assemblyAssembly of cylinders, links, actuators, and gears permits landing-gear unit to be retracted into shadow of main engine intake ducts of supersonic transport aircraft. This is accomplished without adding to frontal area of aircraft or appreciably increasing total aircraft drag.2 ppARC-10786
- Low-Reynolds Number Aerodynamics of an 8.9 Percent Scale Semispan Swept Wing for Assessment of Icing EffectsThis paper presents the results of an experimental and computational study of low-Reynolds number swept wing aerodynamics. This work has been conducted in preparation for icing effects on a swept wing. A complete abstract will be written for the final paper.24 pp20170007300
- Low-speed characteristics of a variable-sweep supersonic transport model with a blended engine fuselage and engine-mounted tailsLow-speed characteristics of variable-sweep supersonic transport model with blended engine fuselage and engine-mounted tails81 ppNASA-TM-X-1038
- Low-speed characteristics of four cambered, 10-percent-thick NACA airfoil sections26 ppNACA-TN-2177
- Low-Speed Dynamic Wind Tunnel Test Analysis of a Generic 53 Degree Swept UCAV Configuration With ControlsSeveral static and dynamic forced-motion wind tunnel tests have been conducted on a generic unmanned combat air vehicle (UCAV) configuration with a 53deg swept leading edge. These tests are part of an international research effort to assess and advance the state-of-art of computational fluid…23 ppAIAA Paper-2014-2003
- Low-speed Investigation of the Effect of Small Canard Surfaces on the Directional Stability of a Sweptback-wing Fighter-airplane ModelLow-speed free flight tunnel testing of swept wing fighter aircraft for determining effect of small canard surfaces on directional stability23 pp19660024811
- Low-Speed Investigation Of The Effects Of Horizontal-Tail Area And Wing Sweep On The Static Longitudinal Stability And Control Characteristics Of An Airplane Configuration Having Tail Surfaces Outboard Of The Wing TipsLow-speed longitudinal static stability & control characteristics of aircraft with swept wings & tail surfaces outboard of wing tips30 ppNASA-MEMO-6-11-59L
- Low-speed Roll Effectiveness of a Differentially Deflected Horizontal-tail Surface on a 42 Deg Swept-wing ModelFree flight tunnel testing of swept wing aircraft model to determine roll effectiveness of differentially deflected horizontal tail26 pp19660024812
- Low-speed stability and control characteristics of a transport model with aft-fuselage-mounted advanced turbopropsA limited experimental investigation was conducted in the Langley 4- by 7-Meter Tunnel to explore the effects of aft-fuselage-mounted advanced turboprop installations on the low-speed stability and control characteristics of a representative transport aircraft in a landing configuration. In…68 ppNASA-TP-2535
- Low-Speed Stability and Control Test of a "Double-Bubble" Transport ConfigurationA test in the Langley 12-Foot Low-Speed Tunnel was conducted as a risk mitigation effort to quickly obtain some low-speed stability and control data on a "double-bubble" or D8 transport configuration. The test also tested some configuration design trades. A 5-percent scale model was tested with…52 ppNASA/TM-2017-219797
- Low-speed wind-tunnel studies relating to pitch-up on a supersonic transport model with a high-aspect-ratio variable-sweep wingLow speed wind tunnel testing of high aspect ratio variable sweep wing supersonic transport model for determining methods of reducing pitch-up tendency76 pp19660023730
- Low-speed Wind-Tunnel Study of Reaction Control-jet Effectiveness for Hover and Transition of a STOVL Fighter ConceptA brief wind-tunnel study was conducted in the Langley 12-Foot Low-Speed Tunnel to determine reaction control-jet effectiveness and some associated aerodynamic characteristics of a 15 percent scale model of the General Dynamics E-7A STOVL fighter/attack aircraft concept applicable to hover and…39 ppNASA-TM-4147
- Low-speed wind-tunnel study of the high-angle-of-attack stability and control characteristics of a cranked-arrow-wing fighter configurationThe low-speed, high-angle-of-attack stability and control characteristics of a fighter configuration incorporating a cranked arrow wing were investigated in the Langley 30- by 60-foot tunnel as part of a NASA/General Dynamics cooperative research program to investigate the application of advanced…39 ppNASA-TM-85776
- Low-speed wind-tunnel test of a STOL supersonic-cruise fighter conceptA wind-tunnel investigation was conducted to examine the low-speed static stability and control characteristics of a 0.10 scale model of a STOL supersonic cruise fighter concept. The concept, referred to as a twin boom fighter, was designed as a STOL aircraft capable of efficient long range…45 ppNASA-TM-4050
- Mars Helicopter Ingenuity Rotor GeometryThe NASA Mars Helicopter Ingenuity performed its maiden flight on April 19, 2021, and opened new possibilities for planetary exploration. Ingenuity has ended its mission after experiencing an anomaly during its 72nd flight on January 18, 2024. Due to the low density and low temperature of the…89 pp
- Mars Science Helicopter Rotor GeometryThe Jet Propulsion Laboratory and NASA Ames Research Center are exploring possibilities for a Mars Science Helicopter (MSH), a second-generation Mars rotorcraft designed to conduct science investigations independently of a lander or rover. The goal of the MSH concept design is to establish the…57 ppNASA/TM-20240013701
- Material Challenges and Opportunities for Commercial Electric AircraftSignificant reduction in carbon dioxide emission for future air transportation system will require adoption of electric propulsion system and more electric architectures. Various options for aircraft electric propulsion include hybrid electric, turboelectric, and full electric system. Realization…25 pp20140017337
- Materials and Processes for New Propulsion Systems with Reduced Environmental ImpactAeronautics research at NASA Glenn Research Center includes development, characterization and modeling of high temperature, lightweight materials and fabrication processes for aircraft propulsion systems with increased efficiency and reduced emissions, fuel burn and noise. Current propulsion…20 pp20190032203
- Materials Aspects of Turboelectric Aircraft PropulsionThe turboelectric distributed propulsion approach for aircraft makes a contribution to all four "corners" of NASA s Subsonic Fixed Wing trade space, reducing fuel burn, noise, emissions and field length. To achieve the system performance required for the turboelectric approach, a number of advances…19 pp20090042355
- Materials for the mach 3 supersonic transportMaterials and alloys for Mach 3 supersonic transport5 ppNASA-TM-X-56492
- Mathematical model for lift/cruise fan V/STOL aircraft simulator programming dataSimulation data are reported for the purpose of programming the flight simulator for advanced aircraft for tests of the lift/cruise fan V/STOL Research Technology Aircraft. These simulation tests are to provide insight into problem areas which are encountered in operational use of the aircraft. A…265 pp19770007094
- MATLAB Stability and Control Toolbox Trim and Static Stability ModuleMATLAB Stability and Control Toolbox (MASCOT) utilizes geometric, aerodynamic, and inertial inputs to calculate air vehicle stability in a variety of critical flight conditions. The code is based on fundamental, non-linear equations of motion and is able to translate results into a qualitative,…1 ppLAR-17483-1
- Matlab Stability and Control Toolbox: Trim and Static Stability ModuleThis paper presents the technical background of the Trim and Static module of the Matlab Stability and Control Toolbox. This module performs a low-fidelity stability and control assessment of an aircraft model for a set of flight critical conditions. This is attained by determining if the control…20 ppNASA/TM-2006-214536
- Maximum likelihood identification and optimal input design for identifying aircraft stability and control derivativesA new method of extracting aircraft stability and control derivatives from flight test data is developed based on the maximum likelihood cirterion. It is shown that this new method is capable of processing data from both linear and nonlinear models, both with and without process noise and includes…212 ppNASA-CR-2200
- Maximum Mean Lift Coefficient Characteristics at Low Tip Mach Numbers of a Hovering Helicopter Rotor Having an NACA 64(1)A012 Airfoil SectionAn investigation has been conducted on the Langley helicopter test tower to determine experimentally the maximum mean lift-coefficient characteristics at low tip Mach number and a limited amount of drag- divergence data at high tip Mach number of a helicopter rotor having an NACA 64(1)AO12 airfoil…28 ppNASA-MEMO-1-23-59L
- Measured performance of a tip-controlled, teetered rotor with an NACA 64 sub 3-618 tip airfoilTests were conducted on the Mod-O 100 kW Wind Turbine to determine the performance of a tip-controlled rotor having an NACA 64 sub-618 airfoil over the moveable outboard 30% of the blade, while operating at nominal rotor speeds of 21 and 31 rpm. Tests were conducted at two rotor speeds to assess…17 ppNASA-TM-82870
- Measurement and analysis of aircraft far-field aerodynamic noiseA systematic investigation of aircraft far-field radiated, aerodynamically generated noise was conducted. The test phase of the original program involved the measurement of the noise produced by five gliding aircraft in an aerodynamically clean configuration during low altitude flyovers. These…70 pp19750003910
- Measurement of Attachment-Line Location in a Wind-Tunnel and in Supersonic FlightAs a part of the supersonic laminar flow control research program, experiments are being conducted to measure the attachment-line flow characteristics and its location on a highly swept aircraft wing. Initially, subsonic wind tunnel tests were performed on two-dimensional models to develop sensors…11 ppAIAA-92-4089
- Measurement of model aeroelastic deformations in the wind tunnel at transonic speeds using stereophotogrammetryA stereophotographic method of determining the aeroelastic deformations of an airplane model under aerodynamic load in the wind tunnel was evaluated. Wind tunnel tests were conducted in the Langley 8 foot transonic pressure tunnel on the wing of a 0.0625 scale model of the TF-8A supercritical wing…48 pp19780002105
- Measurement of Model Noise in a Hard-Wall Wind TunnelIdentification, analysis, and control of fluid-mechanically-generated sound from models of aircraft and automobiles in special low-noise, semi-anechoic wind tunnels are an important research endeavor. Such studies can also be done in aerodynamic wind tunnels that have hard walls if phased…2 ppARC-14967
- Measurements Obtained During the First Landing of the North American X-15 Research AirplaneThe first landing of the X-15 airplane was made at 8:43 a.m., June 8, 1959, on the hard surface of Rogers Dry Lake. One purpose of the first-glide flight was to evaluate the effectiveness of the landing-gear system. Some results are presented of the landing-approach characteristics, the impact…38 pp19980227362
- Measurements of V/STOL aircraft noise mechanisms using pressure cross-correlation techniques in a reverberant wind tunnelA 3.8 cm. model jet was operated in a wind tunnel with cross-flow in order to determine the effect on jet noise radiated characteristics. A method was developed for the determination of noise radiating characteristics of sources within reverberant wind tunnels; cross-correlation measurements were…78 ppNASA-CR-137627
- Mechanical design of a Curtis turbine for the oxidizer turbopump of the M-1 engineTurbine mechanical design for M-1 engine oxidizer turbopump165 ppNASA-CR-54815
- Metal matrix composites for aircraft propulsion systemsStudies of advanced aircraft propulsion systems have indicated that performance gains and operating costs are possible through the application of metal matrix composites. Compressor fan blades and turbine blades have been identified as components with high payoff potential as a result of these…24 pp19750011173
- Method and apparatus for producing an aircraft flare path control signalAircraft altitude, ground velocity, and altitude rate signals are input to a computer which, using a unique control law, generates a pitch control surface command signal suitable for guiding an aircraft on its flare path to a specified runway touchdown point despite varying wind conditions.6 ppPatent Application Number: US-PATENT-APPL-SN-162451
- Method to Generate Full-Span Ice Shape on Swept Wing Using Icing Tunnel DataThere is a collaborative research program by NASA, FAA, ONERA, and university partners to improve the fidelity of experimental and computational simulation methods for swept-wing ice accretion formulations and resultant aerodynamic effects on large transport aircraft. This research utilizes a 65…20 pp20150019656
- Methodology for design of active controls for V/STOL aircraftAn effort to develop techniques for the design of integrated, fully automatic flight control systems for powered lift STOL and VTOL aircraft is described. The structure is discussed of the control system which has been developed to deal with the strong nonlinearities inherent in this class of…9 pp
- Methods for comparative evaluation of propulsion system designs for supersonic aircraftThe propulsion system comparative evaluation study was conducted to define a rapid, approximate method for evaluating the effects of propulsion system changes for an advanced supersonic cruise airplane, and to verify the approximate method by comparing its mission performance results with those…189 pp19770011212
- MIMO Sliding Mode Control for a Tailless Fighter Aircraft, An Alternative to Reconfigurable ArchitecturesA frequency-domain procedure for the design of sliding mode controllers for multi-input, multi-output (MIMO) systems is presented. The methodology accommodates the effects of parasitic dynamics such as those introduced by unmodeled actuators through the introduction of multiple asymptotic observers…48 pp
- Minimum Drag of Four Versions of a Swept-wing Fighter Airplane Obtained from Flight Tests of Rocket-boosted Models at Mach Numbers from 0.81 to 1.71Swept wing fighter aircraft drag coefficient reduction by configuration redesign28 pp19660024810
- Minimum Specific Fuel Consumption of a Liquid-Cooled Multicylinder Aircraft Engine as Affected by Compression Ratio and Engine Operating ConditionsAn investigation was conducted on a 12-cylinder V-type liquid-cooled aircraft engine of 1710-cubic-inch displacement to determine the minimum specific fuel consumption at constant cruising engine speed and compression ratios of 6.65, 7.93, and 9.68. At each compression ratio, the effect.of the…39 pp20090023708
- Misconceptions of Electric Propulsion Aircraft and Their Emergent Aviation MarketsOver the past several years there have been aircraft conceptual design and system studies that have reached conflicting conclusions relating to the feasibility of full and hybrid electric aircraft. Some studies and propulsion discipline experts have claimed that battery technologies will need to…17 pp20140011913
- Mission Analysis and Aircraft Sizing of a Hybrid-Electric Regional AircraftThe purpose of this study was to explore advanced airframe and propulsion technologies for a small regional transport aircraft concept (~50 passengers), with the goal of creating a conceptual design that delivers significant cost and performance advantages over current aircraft in that class. In…16 pp20160007763
- Mixed-Phase Icing Simulation and Testing at the Cox Icing Wind TunnelA new capability was developed for indoor simulation of snow and mixed-phase icing conditions. This capability is useful for year-round testing in the Cox closed-loop Icing Wind Tunnel. Certification of aircraft for flight into these types of icing conditions is only required by the JAA in Europe.…18 ppNASA/TM-2003-212395
- Mixer Assembly for a Gas Turbine EngineA mixer assembly for a gas turbine engine is provided, including a main mixer with fuel injection holes located between at least one radial swirler and at least one axial swirler, wherein the fuel injected into the main mixer is atomized and dispersed by the air flowing through the radial swirler…11 pp20150004018
- Mixer Assembly for a Gas Turbine EngineA mixer assembly for a gas turbine engine is provided, including a main mixer with fuel injection holes located between at least one radial swirler and at least one axial swirler, wherein the fuel injected into the main mixer is atomized and dispersed by the air flowing through the radial swirler…11 pp20180002533
- Mixing in supersonic flowMethod for determining turbulent transport coefficient in supersonic flow61 ppNASA-CR-82526
- Modal control of an oblique wing aircraftA linear modal control algorithm is applied to the NASA Oblique Wing Research Aircraft (OWRA). The control law is evaluated using a detailed nonlinear flight simulation. It is shown that the modal control law attenuates the coupling and nonlinear aerodynamics of the oblique wing and remains stable…48 ppNASA-TP-2898
- Modal control theory and application to aircraft lateral handling qualities designA multivariable synthesis procedure based on eigenvalue/eigenvector assignment is reviewed and is employed to develop a systematic design procedure to meet the lateral handling qualities design objectives of a fighter aircraft over a wide range of flight conditions. The closed loop modal…64 pp19780017158
- Modal Filtering for Control of Flexible AircraftModal regulators and deformation trackers are designed for an open-loop fluttering wing model. The regulators are designed with modal coordinate and accelerometer inputs respectively. The modal coordinates are estimated with simulated fiber optics. The robust stability of the closed-loop systems is…48 ppNASA/TM-2013-216597
- Mode-Based Sensing and Actuation Techniques for Multi-Objective Flexible Aircraft ControlIntelligent sensing and actuation designs are explored as a means to improve performance of a gust load alleviation control design for a flexible wing aircraft equipped with wing-shaping control surfaces. The proposed techniques rely on identification of the dominant structural modes during…12 ppAIAA 2020-1622
- Model helicopter rotor high-speed impulsive noise: Measured acoustics and blade pressuresA 1/17-scale research model of the AH-1 series helicopter main rotor was tested. Model-rotor acoustic and simultaneous blade pressure data were recorded at high speeds where full-scale helicopter high-speed impulsive noise levels are known to be dominant. Model-rotor measurements of the peak…35 ppNASA-TM-85850
- Model Preparation, Operations, and AccessCryogenic, high-Reynolds number testing has been in use for approximately 40 years. This reliable testing capability is used to more closely predict full-scale flight aerodynamics for improved accuracy in estimates of aircraft performance, stability, and loads. A technical course has been created…30 pp20200005420
- Model studies of crosswind landing-gear configurations for STOL aircraftA dynamic model was used to directly compare four different crosswind landing gear mechanisms. The model was landed as a free body onto a laterally sloping runway used to simulate a crosswind side force. A radio control system was used for steering to oppose the side force as the model rolled to a…
- Model-following control for an oblique-wing aircraftA variable-skew oblique wing offers a substantial aerodynamic performance advantage for aircraft missions that require both high efficiency in subsonic flight and supersonic dash or cruise. The most obvious characteristic of the oblique-wing concept is the asymmetry associated with wing-skew angle…13 ppNASA-TM-88269
- Modeling and Control Design for a Turboelectric Single Aisle Aircraft Propulsion SystemA nonlinear dynamic model with full flight envelope controller is developed for the propulsion system of a partially turboelectric single-aisle aircraft. The propulsion system model consists of two turbofan engines with a large percentage of power extraction, feeding an electric tail fan for…19 pp20180005436
- Modeling and parameter uncertainties for aircraft flight control system designValues of plant dynamic uncertainties for some recent aircraft design and development programs are given. Histories of pertinent aerodynamic, inertial, and structural parameter variations are given for a period of time from program initiation to aircraft certification. These data can be used as…133 pp19770026205
- Modeling and Validation of a Navy A6-Intruder Actively Controlled Landing Gear SystemConcepts for long-range air travel are characterized by airframe designs with long, slender, relatively flexible fuselages. One aspect often overlooked is ground-induced vibration of these aircraft. This paper presents an analytical and experimental study of reducing ground-induced aircraft…32 ppNASA/TP-1999-209124
- Modeling Materials: Design for Planetary Entry, Electric Aircraft, and BeyondNASA missions push the limits of what is possible. The development of high-performance materials must keep pace with the agency's demanding, cutting-edge applications. Researchers at NASA's Ames Research Center are performing multiscale computational modeling to accelerate development times and…1 pp20160003111
- Modeling the Benchmark Active Control Technology Wind-Tunnel Model for Application to Flutter SuppressionThis paper describes the formulation of a model of the dynamic behavior of the Benchmark Active Controls Technology (BACT) wind-tunnel model for application to design and analysis of flutter suppression controllers. The model is formed by combining the equations of motion for the BACT wind-tunnel…12 pp20040110943
- Moving base simulation of an integrated flight and propulsion control system for an ejector-augmentor STOVL aircraft in hoverA piloted motion simulator evaluation, using the NASA Ames Vertical Motion Simulator, was conducted in support of a NASA Lewis Contractual study of the integration of flight and propulsion systems of a STOVL aircraft. Objectives of the study were to validate the Design Methods for Integrated…34 pp19950024225
- Multi-fuel rotary engine for general aviation aircraftDesign studies of advanced multifuel general aviation and commuter aircraft rotary stratified charge engines are summarized. Conceptual design studies were performed at two levels of technology, on advanced general aviation engines sized to provide 186/250 shaft kW/hp under cruise conditions at…47 pp19830020964
- Multi-Fuel Rotary Engine for General Aviation AircraftDesign studies, conducted for NASA, of Advanced Multi-fuel General Aviation and Commuter Aircraft Rotary Stratified Charge Engines are summarized. Conceptual design studies of an advanced engine sized to provide 186/250 shaft KW/HP under cruise conditions at 7620/25,000 m/ft. altitude were…86 pp19830027760
- Multi-heat addition turbine engineA multi-heat addition turbine engine (MHATE) incorporates a plurality of heat addition devices to transfer energy to air and a plurality of turbines to extract energy from the air while converting it to work. The MHATE provides dry power and lower fuel consumption or lower combustor exit…7 pp19930012845
- Multicriteria Gain Tuning for Rotorcraft Flight Controls (also entitled The Development of the Conduit Advanced Control System Design and Evaluation Interface with a Case Study Application Fly by Wire Helicopter Design)Handling qualities analysis and control law design would seem to be naturally complimenting components of aircraft flight control system design, however these two closely coupled disciplines are often not well integrated in practice. Handling qualities engineers and control system engineers may…101 pp19990047878
- Multidisciplinary Design Optimization of a Transonic Truss-Braced Wing using Physics-Based ModelsShifting economic forces have placed pressure on the aviation industry to produce future aircraft designs with substantial performance improvements over those flying today. To meet these ambitious goals, new concepts are being considered that diverge from the traditional tube-and-wing design, such…19 pp
- Multidisciplinary Techniques and Novel Aircraft Control SystemsThe Aircraft Morphing Program at NASA Langley Research Center explores opportunities to improve airframe designs with smart technologies. Two elements of this basic research program are multidisciplinary design optimization (MDO) and advanced flow control. This paper describes examples where MDO…14 ppAIAA Paper 2000-4848
- Multiplanar Synthetic Arrays and Their Application to Full-Scale Landing Gear Noise Source IdentificationIdentification and quantification of noise sources generated by the landing gears of large civil transports are critical for the development of viable abatement technologies that can be applied locally to affect solely the source regions. Leveraging validated computational data sets obtained from…32 pp
- Multiple Kernel Learning for Heterogeneous Anomaly Detection: Algorithm and Aviation Safety Case StudyThe world-wide aviation system is one of the most complex dynamical systems ever developed and is generating data at an extremely rapid rate. Most modern commercial aircraft record several hundred flight parameters including information from the guidance, navigation, and control systems, the…9 ppARC-E-DAA-TN-1240
- Multiplexing electro-optic architectures for advanced aircraft integrated flight control systemsThis report describes the results of a 10 month program sponsored by NASA. The objective of this program was to evaluate various optical sensor modulation technologies and to design an optimal Electro-Optic Architecture (EOA) for servicing remote clusters of sensors and actuators in advanced…94 ppNASA-CR-182268
- Multivariable control of a forward swept wing aircraftThe impact of independent canard and flaperon control of the longitudinal axis of a generic forward swept wing aircraft is examined. The Linear Quadratic Gaussian (LQG)/Loop Transfer Recovery (LTR) method is used to design three compensators: two single-input-single-output (SISO) systems, one with…144 ppNASA-CR-177112
- NACA Conference on Aerodynamics of High- speed Aircraft A compilation of the papers presentedConference on aerodynamics of high speed aircraft632 pp19660006294
- NACA Conference on Aircraft Loads, Structures, and FlutterThis document contains reproductions of technical papers on some of the most recent research results on aircraft loads, flutter, and structures from the NACA laboratories. These papers were presented by members of the staff of the NACA laboratories at the Conference held at the Langley Aeronautical…614 pp19710070068
- NACA Stall-Warning IndicatorThe stall-warning indicator employs a total-head tube located close to the wing surface in a region wherein local stalling occurs before the main portion of the wing stalls. The artificial production of a localized stalled region is accomplished by means of a sharp leading edge extending a few…15 ppNACA-TN-670
- NASA aerodynamics programThe annual accomplishments is reviewed for the Aerodynamics Division during FY 1991. The program includes both fundamental and applied research directed at the full spectrum of aerospace vehicles, from rotorcraft to planetary entry probes. A comprehensive review is presented of the following…254 pp19920015435
- NASA Aircraft Controls Research, 1983The workshop consisted of 24 technical presentations on various aspects of aircraft controls, ranging from the theoretical development of control laws to the evaluation of new controls technology in flight test vehicles. A special report on the status of foreign aircraft technology and a panel…612 ppNASA-CP-2296
- NASA Airframe Icing Research Overview Past and CurrentThis slide presentation reviews the past and current research that NASA has done in the area of airframe icing. Both the history experimental efforts and model development to understand the process and problem of ice formation are reviewed. This has resulted in the development of new experimental…34 pp
- NASA and general aviationGeneral aviation remains the single most misunderstood sector of aeronautics in the United States. A detailed look at how general aviation functions and how NASA helps keep it on the cutting edge of technology in airfoils, airframes, commuter travel, environmental concerns, engines, propellers, air…140 ppNASA-SP-485
- NASA Armstrong Flight Research Center Dynamics and Controls BranchNASA Armstrong continues its legacy of exciting work in the area of Dynamics and Control of advanced vehicle concepts. This presentation describes Armstrongs research in control of flexible structures, peak seeking control and adaptive control in the Spring of 2015.9 pp20150002848
- NASA Aviation Safety Program Weather Accident Prevention/weather Information Communications (WINCOMM)Weather is a contributing factor in approximately 25-30 percent of general aviation accidents. The lack of timely, accurate and usable weather information to the general aviation pilot in the cockpit to enhance pilot situational awareness and improve pilot judgment remains a major impediment to…69 ppNASA/CR-2002-211903
- NASA aviation safety reporting systemThe study deals with 165 inadvertent operations on or into inappropriate portions of the aircraft areas at controlled airports. Pilot-initiated and controller-initiated incursions are described and discussed. It was found that a majority of the pilot-initiated occurrences involved operation without…20 ppNASA-TM-78540
- NASA Aviation Safety Reporting SystemThis presentation provides an overview of NASA's Aviation Safety Reporting System.32 pp
- NASA Aviation Safety Reporting System (ASRS) Program BriefingThis presentation provides an overview of NASA's Aviation Safety Reporting System (ASRS).30 pp
- NASA Electric Propulsion System StudiesAn overview of NASA efforts in the area of hybrid electric and turboelectric propulsion in large transport. This overview includes a list of reasons why we are looking at transmitting some or all of the propulsive power for the aircraft electrically, a list of the different types of hybrid-turbo…14 pp20160009274
- NASA Electrified Aircraft Propulsion EffortsNASA's broad investments in Electrified Aircraft Propulsion (EAP) are reviewed in this paper. NASA investments are guided by an assessment of potential market impacts, technical key performance parameters, and technology readiness attained through a combination of studies, enabling fundamental…11 pp20190032511
- NASA Environmentally Responsible Aviation Hybrid Wing Body Flow-Through Nacelle Wind Tunnel CFDWind tunnel tests of a 5.75 scale model of the Boeing Hybrid Wing Body (HWB) configuration were conducted in the NASA Langley Research Center (LaRC) 14x22 and NASA Ames Research Center (ARC) 40x80 low speed wind tunnels as part of the NASA Environmentally Responsible Aviation (ERA) Project.…42 ppARC-E-DAA-TN28507
- NASA ERA Integrated CFD for Wind Tunnel Testing of Hybrid Wing-Body ConfigurationThe NASA Environmentally Responsible Aviation (ERA) Project explored enabling technologies to reduce impact of aviation on the environment. One project research challenge area was the study of advanced airframe and engine integration concepts to reduce community noise and fuel burn. To address this…27 ppARC-E-DAA-TN28326
- NASA ERA Integrated CFD for Wind Tunnel Testing of Hybrid Wing-Body ConfigurationNASAs Environmentally Responsible Aviation (ERA) Project explores enabling technologies to reduce aviations impact on the environment. One research challenge area for the project has been to study advanced airframe and engine integration concepts to reduce community noise and fuel burn. In order to…24 ppARC-E-DAA-TN28678
- NASA Fixed Wing Project Propulsion Research and Technology Development Activities to Reduce Thrust Specific Energy ConsumptionThis paper presents an overview of the propulsion research and technology portfolio of NASA Fundamental Aeronautics Program Fixed Wing Project. The research is aimed at significantly reducing the thrust specific fuel/energy consumption of notional advanced fixed wing aircraft (by 60 percent…28 pp20140008324
- Nasa flight research center handling-qualities program on general-aviation aircraftAircraft handling qualities program on general aviation9 pp19650025634
- NASA Glenn Icing Facilities Advancements26 pp
- NASA Glenn Icing Facilities Update16 pp
- NASA Glenn Icing Research Tunnel: 2014 Cloud CalibrationThe results of the December 2013 to February 2014 Icing Research Tunnel full icing cloud calibration are being presented to the SAE AC-9C committee, as represented in the 2014 cloud calibration report. The calibration steps included establishing a uniform cloud and conducting drop size and liquid…15 ppGRC-E-DAA-TN18729
- NASA Glenn Icing Research Tunnel: 2014 Cloud Calibration Procedure and ResultsThe results of the December 2013 to February 2014 Icing Research Tunnel full icing cloud calibration are presented. The calibration steps included establishing a uniform cloud and conducting drop size and liquid water content calibrations. The goal of the calibration was to develop a uniform cloud,…24 pp20140017464
- NASA Glenn Propulsion Systems Lab (PSL) Icing Facility UpdateThe NASA Glenn Research Center Propulsion Systems Lab (PSL) was recently upgraded to perform engine inlet ice crystal testing in an altitude environment. The system installed 10 spray bars in the inlet plenum for ice crystal generation using 222 spray nozzles. As an altitude test chamber, PSL is…17 pp20150014235
- NASA Glenn's Contributions to Aircraft Engine Noise ResearchThis presentation reviews engine noise research conducted at the NASA Glenn Research Center over the past 70 years. This report includes a historical perspective of the Center and the facilities used to conduct the research. Major noise research programs are highlighted to show their impact on…18 ppGRC-E-DAA-TN16375
- NASA Glenn's Contributions to Aircraft Engine Noise ResearchThis report reviews all engine noise research conducted at the NASA Glenn Research Center over the past 70 years. This report includes a historical perspective of the Center and the facilities used to conduct the research. Major noise research programs are highlighted to show their impact on…50 pp20140006523
- NASA Heavy Lift Rotorcraft Systems InvestigationThe NASA Heavy Lift Rotorcraft Systems Investigation examined in depth several rotorcraft configurations for large civil transport, designed to meet the technology goals of the NASA Vehicle Systems Program. The investigation identified the Large Civil Tiltrotor as the configuration with the best…108 pp20060023335
- NASA Iced Aerodynamics and Controls Current ResearchThis slide presentation reviews the state of current research in the area of aerodynamics and aircraft control with ice conditions by the Aviation Safety Program, part of the Integrated Resilient Aircraft Controls Project (IRAC). Included in the presentation is a overview of the modeling efforts.…12 pp20090030603
- NASA Icing Overview 2023This presentation summarizes NASA icing research for an invited talk to be presented on June 22, 2023, at the SAE International Conference on Icing of Aircraft, Engines, and Structures. The presentation describes the NASA icing portfolio including facilities and computational tools. In addition,…29 pp
- NASA Icing UpdateNASA icing research summarizes work in the following areas: facility updates for the Icing Research Tunnel and Propulsion Systems Laboratory, engine icing, and simulation & experimental tools.26 pp
- NASA Icing UpdateThis presentation provides a summary of NASA icing research activities with the focus on new developments and plans over the previous six months. Research highlights are provided from various NASA efforts.13 pp
- NASA Icing UpdateThis NASA Icing Update was prepared for presentation to the SAE International AC-9C Inflight Icing Technology Committee. This update includes the following topics: recently completed propeller icing test in the NASA Icing Research Tunnel; recently completed Icing Research Tunnel Capability…27 pp
- NASA Icing Update – May 2024This presentation provides a status update on select NASA icing research activities for the SAE AC-9C Icing Technical Committee Meeting on May 6, 2024. The updates include the following topics: (1) Propulsion Systems Lab (PSL), (2) Adaptive Icing Tunnel (AIT), (3) Ice Adhesion / Deformed Skin…17 pp
- NASA Icing Update – Oct 2024This presentation provides a status update on select NASA icing research activities for the SAE AC-9C Icing Technical Committee Meeting on Oct 21, 2024. The updates include the following topics: (1) Transonic Truss-Braced Wing Icing, (2) High-Lift Common Research Model Icing (3) Adaptive Icing…18 pp
- NASA Jet Noise ResearchThe presentation highlights NASA's jet noise research for 2016. Jet-noise modeling efforts, jet-surface interactions results, acoustic characteristics of multi-stream jets, and N+2 Supersonic Aircraft system studies are presented.24 pp20170004102
- NASA Langley Distributed Propulsion VTOL Tilt-Wing Aircraft Testing, Modeling, Simulation, Control, and Flight Test DevelopmentControl of complex Vertical Take-Off and Landing (VTOL) aircraft traversing from hovering to wing born flight mode and back poses notoriously difficult modeling, simulation, control, and flight-testing challenges. This paper provides an overview of the techniques and advances required to develop…14 ppNF1676L-17842
- NASA Lewis Research Center's Program on Icing ResearchThe helicopter and general aviation, light transport, and commercial transport aircraft share common icing requirements: highly effective, lightweight, low power consuming deicing systems, and detailed knowledge of the aeropenalties due to ice on aircraft surfaces. To meet current and future needs,…17 ppNASA-TM-83031
- NASA N3-X with Turboelectric Distributed PropulsionPresentation summarizing the phase I study of the NASA N3-X turboelectric distributed propulsion power aircraft to the IMechE Disruptive Green Propulsion Technologies conference in London, UK November 16th and 17th, 2014. This presentation contains the results of a NASA internal study funded by the…18 pp20150002081
- NASA progress in aircraft noise predictionSome of the essential features of aircraft noise prediction are described and the basis for evaluating its capability and future potential is discussed. A takeoff noise optimizing procedure is described which calculates a minimum noise takeoff procedure subject to multiple site noise constraints.38 pp19810010548
- NASA research in aircraft propulsionA broad overview of the scope of research presently being supported by NASA in aircraft propulsion is presented with emphasis on Lewis Research Center activities related to civil air transports, CTOL and V/STOL systems. Aircraft systems work is performed to identify the requirements for the…18 pp19820005273
- NASA Research on General Aviation Power PlantsPropulsion systems are key factors in the design and performance of general aviation airplanes. NASA research programs that are intended to support improvements in these engines are described. Reciprocating engines are by far the most numerous powerplants in the aviation fleet; near-term efforts…15 pp19790003915
- NASA research on noise-abatement approach profiles for multiengine jet transport aircraftNASA research on noise-abatement steepened approaches for multiengine jet transports44 pp19670020029
- NASA research on viscous drag reductionResearch on natural laminar flow, laminar flow control by suction, and turbulent drag reduction is discussed. Preliminary results suggest that a significant amount of natural laminar flow can be achieved on small, straight wing airplanes. On larger, swept wing aircraft, laminar flow control by…32 pp19820025468
- Nasa-faa supersonic transport study news release no- 63-252Supersonic air transport flight profile simulation for air traffic control development and flight planning3 pp
- NASA,FAA,ONERA Swept-Wing Icing and Aerodynamics: Summary of Research and Current StatusNASA, FAA, ONERA, and other partner organizations have embarked on a significant, collaborative research effort to address the technical challenges associated with icing on large scale, three-dimensional swept wings. These are extremely complex phenomena important to the design, certification and…27 ppGRC-E-DAA-TN23372
- NASA's Aircraft Icing Analysis ProgramAn overview of the NASA ongoing efforts to develop an aircraft icing analysis capability is presented. Discussions are included of the overall and long term objectives of the program as well as current capabilities and limitations of the various computer codes being developed. Descriptions are…28 ppNASA-TM-88791
- NASA's aircraft icing technology programNASA' Aircraft Icing Technology program is aimed at developing innovative technologies for safe and efficient flight into forecasted icing. The program addresses the needs of all aircraft classes and supports both commercial and military applications. The program is guided by three key strategic…12 ppNASA-TM-104518
- NASA's Aviary Takes Flight: A Public Software for Aircraft DesignAn overview of the Aviary aircraft modelling and design tool.23 pp
- NASA's Magnetic Gearing Research for Electrified Aircraft PropulsionThis paper presents an overview of the magnetic gearing research being conducted at NASA. First, the research is motivated through an in-depth discussion of the Agency-level aeronautics vision, the benefit of geared drivetrains, the barriers to applying mechanical gears in future aircraft concepts…12 pp20180005333
- NASA's Magnetic Gearing Research for Electrified Aircraft PropulsionThis paper presents an overview of the magnetic gearing research being conducted at NASA. First, the research is motivated through an in-depth discussion of the Agency-level aeronautics vision, the benefit of geared drivetrains, the barriers to applying mechanical gears in future aircraft concepts…21 pp20180005561
- NASA's program on icing research and technologyNASA's program in aircraft icing research and technology is reviewed. The program relies heavily on computer codes and modern applied physics technology in seeking icing solutions on a finer scale than those offered in earlier programs. Three major goals of this program are to offer new approaches…55 ppNASA-TM-101989
- NASA's Role in Aeronautics: A Workshop. Volume 4: General aviationA substantially improved flow of new technology is imperative if the general aviation industry is to maintain a strong world position. Although NASA is the most eminently suited entity available to carry out the necessary research and technology development effort because of its facilities,…44 ppNASA-CR-164516
- NASA's rotorcraft icing research programThe objective of the NASA aircraft icing research program is to develop and make available icing technology to support the needs and requirements of industry for all weather aircraft designs. While a majority of the technology being developed is viewed to be generic (i.e., appropriate to all…31 pp
- NASA's X-57 High Lift Motor Controller: Detailed Design, Test Results, and OutcomesNASA's X-57 all-electric aircraft was a research project aimed at investigating lightweight and efficient electric propulsion components. The general approach was to utilize a distributed electric propulsion (DEP) design. An essential component of this design was the High Lift Motor Controller…14 pp20240008854
- NASA/FAA Tailplane Icing Program OverviewThe effects of tailplane icing were investigated in a four-year NASA/FAA Tailplane Icing, Program (TIP). This research program was developed to improve the understanding, of iced tailplane aeroperformance and aircraft aerodynamics, and to develop design and training aides to help reduce the number…16 pp19990019485
- NASA/Pratt and Whitney experimental clean combustor program: Engine test resultsA two-stage vorbix (vortex burning and mixing) combustor and associated fuel system components were successfully tested in an experimental JT9D engine at steady-state and transient operating conditions, using ASTM Jet-A fuel. Full-scale JT9D experimental engine tests were conducted in a phase three…33 pp19780003125
- National General Aviation Design Competition Guidelines 1999-2000 Academic YearThe National Aeronautics and Space Administration (NASA), the Federal Aviation Administration (FAA) and the Air Force Research Laboratory are sponsoring a National General Aviation Design Competition for students at U.S. aeronautical and engineering universities for the 1999-2000 academic year. The…6 pp20000039430
- National General Aviation Design Competition Project ReportThis report summarizes the management of the National General Aviation Design Competition on behalf of NASA, the FAA and the Air Force by the Virginia Space Grant Consortium (VSGC) for the time period October 1, 1999 through September 30, 2000. This was the VSGC's sixth year of managing the…23 pp20010018998
- National plans for aircraft icing and improved aircraft icing forecasts and associated warning servicesRecently, the United States has increased its activities related to aircraft icing in numerous fields: ice phobics, revised characterization of icing conditions, instrument development/evaluation, de-ice/anti-ice devices, simulated supercooled clouds, computer simulation and flight tests. The…3 pp
- Natural laminar flow and airplane stability and controlLocation and mode of transition from laminar to turbulent boundary layer flow have a dominant effect on the aerodynamic characteristics of an airfoil section. The influences of these parameters on the sectional lift and drag characteristics of three airfoils are examined. Both analytical and…22 pp
- Navier-Stokes, flight, and wind tunnel flow analysis for the F/A-18 aircraftComputational analysis of flow over the F/A-18 aircraft is presented along with complementary data from both flight and wind tunnel experiments. The computational results are based on the three-dimensional thin-layer Navier-Stokes formulation and are obtained from an accurate surface representation…68 ppNASA-TP-3478
- NDARC - NASA Design and Analysis of RotorcraftThe NASA Design and Analysis of Rotorcraft (NDARC) software is an aircraft system analysis tool that supports both conceptual design efforts and technology impact assessments. The principal tasks are to design (or size) a rotorcraft to meet specified requirements, including vertical takeoff and…260 pp20150021267
- NDARC NASA Design and Analysis of Rotorcraft - Input, Appendix 2The NASA Design and Analysis of Rotorcraft (NDARC) software is an aircraft system analysis tool that supports both conceptual design efforts and technology impact assessments. The principal tasks are to design (or size) a rotorcraft to meet specified requirements, including vertical takeoff and…302 pp20160012473
- NDARC NASA Design and Analysis of Rotorcraft Theory Appendix 1The NASA Design and Analysis of Rotorcraft (NDARC) software is an aircraft system analysis tool that supports both conceptual design efforts and technology impact assessments. The principal tasks are to design (or size) a rotorcraft to meet specified requirements, including vertical takeoff and…294 pp20160012474
- NDARC: NASA Design and Analysis of Rotorcraft: Theory - Appendix 3The NASA Design and Analysis of Rotorcraft (NDARC) software is an aircraft system analysis tool that supports both conceptual design efforts and technology impact assessments. The principal tasks are to design (or size) a rotorcraft to meet specified requirements, including vertical takeoff and…296 pp20170011635
- Neural network application to aircraft control system designThe feasibility of using artificial neural networks as control systems for modern, complex aerospace vehicles is investigated via an example aircraft control design study. The problem considered is that of designing a controller for an integrated airframe/propulsion longitudinal dynamics model of a…22 ppNASA-TM-105151
- Neural networks for aircraft controlCurrent research in Artificial Neural Networks indicates that networks offer some potential advantages in adaptation and fault tolerance. This research is directed at determining the possible applicability of neural networks to aircraft control. The first application will be to aircraft trim.…15 pp
- Neural Networks in Nonlinear Aircraft ControlRecent research indicates that artificial neural networks offer interesting learning or adaptive capabilities. The current research focuses on the potential for application of neural networks in a nonlinear aircraft control law. The current work has been to determine which networks are suitable for…11 pp
- New design of hingeless helicopter rotor improves stabilityCantilever blades are attached directly to rotor hub, thereby substantially reducing cost and complexity and increasing reliability of helicopter rotor. Combination of structural flap-lag coupling and pitch-lag coupling provides damping of 6 to 10%, depending on magnitude of coupling parameters.1 ppARC-10807
- New development in flying qualities with application to rotary wing aircraftSome recent considerations and developments in handling quality criteria are reviewed with emphasis on using fixed wing experience gained in developing MIL-F-8785C and the more recent MiL Standard and Handbook. Particular emphasis is placed on the tasks and environmental conditions used to develop…6 pp19820015352
- New Flutter Analysis Technique for Time-Domain Computational AeroelasticityThis presentation is a conference companion and discusses a new flutter analysis technique using CFD results.20 pp20170000462
- New Flutter Analysis Technique for Time-Domain Computational AeroelasticityA new time-domain approach for computing flutter speed is presented. Based on the time-history result of aeroelastic simulation, the unknown unsteady aerodynamics model is estimated using a system identification technique. The full aeroelastic model is generated via coupling the estimated unsteady…18 pp20170000456
- New Icing Cloud Simulation System at the NASA Glenn Research Center Icing Research TunnelA new spray bar system was designed, fabricated, and installed in the NASA Glenn Research Center's Icing Research Tunnel (IRT). This system is key to the IRT's ability to do aircraft in-flight icing cloud simulation. The performance goals and requirements levied on the design of the new spray bar…24 ppNASA/TM-1999-208891
- New opportunities for future, small, General-Aviation Turbine Engines (GATE)The results of four independent contracted studies to explore the opportunities for future small turbine engines are summarized in a composite overview. Candidate advanced technologies are screened, various cycles and staging arrangements are parametrically evaluated, and optimum conceptual engines…26 pp19800013848
- New Spray Bar System Installed in NASA Lewis' Icing Research TunnelNASA Lewis Research Center's Icing Research Tunnel (IRT) is the world's largest refrigerated wind tunnel dedicated to the study of aircraft icing. In the IRT, natural icing conditions are duplicated to test the effects of in-flight icing on actual aircraft components and on scale models of…2 pp20050181937
- Next Generation Civil Transport Aircraft Design Considerations for Improving Vehicle and System-Level EfficiencyThe future of aviation will benefit from research in aircraft design and air transportation management aimed at improving efficiency and reducing environmental impacts. This paper presents civil transport aircraft design trends and opportunities for improving vehicle and system-level efficiency.…15 ppARC-E-DAA-TN10383
- Noise Spectra and Directivity For a Scale-Model Landing GearAn extensive experimental study has been conducted to acquire detailed noise spectra and directivity data for a high-fidelity, 6.3%-scale, Boeing 777 main landing gear. The measurements were conducted in the NASA Langley Quiet Flow Facility using a 41-microphone directional array system positioned…22 ppAIAA 2007-3458
- Non-engine aerodynamic noise investigation of a large aircraftA series of flyover noise measurements have been accomplished utilizing a large jet transport aircraft with engine power reduced to flight idle. It was determined that the aerodynamic (nonengine) noise levels did occur in the general range that had been predicted by using small aircraft (up to…56 pp19740026369
- Nonclassical Flight Control for Unhealthy AircraftThis research set out to investigate flight control of aircraft which has sustained damage in regular flight control effectors, due to jammed control surfaces or complete loss of hydraulic power. It is recognized that in such an extremely difficult situation unconventional measures may need to be…24 ppNASA/CR-97-206660
- Nonlinear Dynamic Control Derivative Analysis for Aircraft with Application to Transonic Truss-Braced WingThis paper presents the development of a nonlinear dynamic control derivative estimation method. A nonlinear aerodynamic model is developed to account for the effects of large control surface deflections on aircraft aerodynamic forces and moments. A series of unsteady RANS CFD simulations is…16 pp
- Nonlinear stability and control study of highly maneuverable high performance aircraftThis project is intended to research and develop new nonlinear methodologies for the control and stability analysis of high-performance, high angle-of-attack aircraft such as HARV (F18). Past research (reported in our Phase 1, 2, and 3 progress reports) is summarized and more details of final Phase…122 ppNASA-CR-193480
- Nonlinear stability and control study of highly maneuverable high performance aircraftThe purpose was to develop and apply new nonlinear system methodologies to the stability analysis and adaptive control of high angle of attack (alpha) aircraft such as the F-18. Considerable progress is documented on nonlinear adaptive control and associated model development, identification, and…81 ppNASA-CR-188721
- Nonlinear stability and control study of highly maneuverable high performance aircraft, phase 2Research leading to the development of new nonlinear methodologies for the adaptive control and stability analysis of high angle of attack aircraft such as the F-18 is discussed. The emphasis has been on nonlinear adaptive control, but associated model development, system identification, stability…64 ppNASA-CR-189911
- Nonlinear stability and control study of highly maneuverable high performance aircraft, phase 2This research should lead to the development of new nonlinear methodologies for the adaptive control and stability analysis of high angle-of-attack aircraft such as the F18 (HARV). The emphasis has been on nonlinear adaptive control, but associated model development, system identification,…69 ppNASA-CR-190667
- Nonlinear Time-Domain System Identification of Aircraft Stability and Control DerivativesThis paper presents a nonlinear time-domain system identification method to estimate the stability derivatives for NASA-Boeing Transonic Truss-Braced Wing configuration. Nonlinear aerodynamics in large-amplitude forced oscillations can cause significant frequency interactions with the linear…16 pp
- Notes on Factors Affecting Geometrical Arrangement of Tricycle-Type Landing GearThe effects of the geometrical arrangement of tricycle landing gears on various characteristics of an airplane equipped with such landing gear is discussed. The characteristics discussed include directional stability, overturning tendencies, steering and ground handling, shimmy, takeoff, and…16 ppNACA-SR-63
- Nowcasting Aircraft Icing Conditions in the Presence of Multilayered Clouds Using Meteorological Satellite DataCloud properties retrieved from satellite data are used to diagnose aircraft icing threat in single layer and multilayered ice-over-liquid clouds. The algorithms are being applied in real time to the Geostationary Operational Environmental Satellite (GOES) data over the CONUS with multilayer data…6 ppPaper 2011-38-0041
- Numerical and Analytical Assessment of a Coupled Rotating Detonation Engine and Turbine ExperimentAn analysis is presented of an experimental rig comprising a rotating detonation engine (RDE) with bypass ejector flow coupled to a downstream turbine. The analysis used a validated computational fluid dynamics RDE simulation combined with straightforward algebraic mixing equations for the bypass…13 ppAIAA 2017-1746
- Numerical CFD Simulation and Test Correlation in a Flight Project EnvironmentThis paper presents detailed description of a novel CFD procedure and comparison of its solution results to that obtained by other available CFD codes as well as actual flight and wind tunnel test data pertaining to the GIII aircraft, currently undergoing flight testing at AFRC.18 pp20160000560
- Numerical CFD Simulation and Test Correlation in a Flight Project EnvironmentThis paper presents detailed description of a novel CFD procedure and comparison of its solution results to that obtained by other available CFD codes as well as actual flight and wind tunnel test data pertaining to the GIII aircraft, currently undergoing flight testing at AFRC.9 pp20160000559
- Numerical investigation of performance degradation of wings and rotors due to icingDuring the past five years, under the support of the NASA Lewis Research Center, a research program related to aircraft and rotorcraft icing has been underway at Georgia Institute of Technology. The objectives of this effort are: (1) develop solution techniques capable of computing 3-D unsteady…14 pp19930009594
- Numerical Modeling of Anti-icing Systems and Comparison to Test Results on a NACA 0012 AirfoilA series of experimental tests were conducted in the NASA Lewis IRT on an electro-thermally heated NACA 0012 airfoil. Quantitative comparisons between the experimental results and those predicted by a computer simulation code were made to assess the validity of a recently developed anti-icing…16 ppNASA-TM-105975
- Numerical optimization design of advanced transonic wing configurationsA computationally efficient and versatile technique for use in the design of advanced transonic wing configurations has been developed. A reliable and fast transonic wing flow-field analysis program, TWING, has been coupled with a modified quasi-Newton method, unconstrained optimization algorithm,…101 pp19840019650
- Numerical simulation of a powered-lift landing, tracking flow features using overset grids, and simulation of high lift devices on a fighter-lift-and-control wingAttached as appendices to this report are documents describing work performed on the simulation of a landing powered-lift delta wing, the tracking of flow features using overset grids, and the simulation of flaps on the Wright Patterson Lab's fighter-lift-and-control (FLAC) wing. Numerical…27 pp19940009849
- Numerical Simulation of Boundary Layer Ingesting (BLI) Inlet-Fan InteractionFuture civil transport designs may incorporate engine inlets integrated into the body of the aircraft to take advantage of efficiency increases due to weight and drag reduction. Additional increases in engine efficiency are predicted if the inlet ingests the lower momentum boundary layer flow.…14 pp20150000132
- Numerical Simulations for Landing Gear Noise Generation and RadiationAerodynamic noise from a landing gear in a uniform flow is computed using the Ffowcs Williams -Hawkings (FW-H) equation. The time accurate flow data on the surface is obtained using a finite volume flow solver on an unstructured and. The Ffowcs Williams-Hawkings equation is solved using surface…88 pp
- Numerical Stability and Control Analysis Towards Falling-Leaf Prediction Capabilities of Splitflow for Two Generic High-Performance Aircraft ModelsAerodynamic analysis are performed using the Lockheed-Martin Tactical Aircraft Systems (LMTAS) Splitflow computational fluid dynamics code to investigate the computational prediction capabilities for vortex-dominated flow fields of two different tailless aircraft models at large angles of attack…58 ppNASA/CR-1998-208730
- Object-oriented approach for gas turbine engine simulationAn object-oriented gas turbine engine simulation program was developed. This program is a prototype for a more complete, commercial grade engine performance program now being proposed as part of the Numerical Propulsion System Simulator (NPSS). This report discusses architectural issues of this…34 pp19950024173
- On identifying frequencies and damping in subcritical flutter testingVarious procedures that might be used in evaluating system response characteristics as involved in subcritical flight and wind-tunnel flutter testing of aircraft are reviewed with emphasis on the means for eliminating or minimizing the contamination effects produced by an unknown noise in the…41 pp19770014079
- On Landing Gear StressesInformation on landing gear stresses is presented on the following: vibratory phenomena, tangential forces applied to landing gear, fore and aft oscillations of landing gears, examples of fatigue failures, vibration calculations, and improvement of existing test equipment.NACA-TM-1422
- On Problems Associated with Modeling Wing-Tail Configurations from Wind Tunnel DataThis paper considers factors that contribute to poor identification of unsteady aerodynamics from wind tunnel data for an airliner configuration. One approach to modeling a wing-tail configuration is considered and applied to both steady and large-amplitude forced pitch oscillation wind tunnel data…18 pp20070030306
- On the prediction of critical flutter conditions from subcritical response data and some related wind-tunnel experienceMethods of interpreting response measurements which could be amenable to flight flutter testing procedures were studied analytically and in the wind tunnel. One suggested scheme, which requires evaluation, is an iterative technique in which derivatives obtained from subcritical response data are…8 pp19760003011
- On-Board Battery Monitoring and Prognostics for Electric-Propulsion AircraftThe reliability of the propulsion system of an aircraft is paramount for the aircraft safety and hence the aircraft health must be monitored continuously. In contrast to fuel- operated aircraft, electric battery-operated propulsion system poses specific problems, such as, the remaining battery…12 pp20190004923
- On-line analysis capabilities developed to support the AFW wind-tunnel testsA variety of on-line analysis tools were developed to support two active flexible wing (AFW) wind-tunnel tests. These tools were developed to verify control law execution, to satisfy analysis requirements of the control law designers, to provide measures of system stability in a real-time…14 ppNASA-TM-107651
- On-Line Mu Method for Robust Flutter Prediction in Expanding a Safe Flight Envelope for an Aircraft Model Under Flight TestA structured singular value (mu) analysis method of computing flutter margins has robust stability of a linear aeroelastic model with uncertainty operators (Delta). Flight data is used to update the uncertainty operators to accurately account for errors in the computed model and the observed range…36 pp20010054946
- Opportunities for aircraft controls researchSeveral problems which drive aircraft control technology are discussed. Highly unstable vehicles, flutter speed boundary expansion, and low level automated flight that follows terrain are discussed.14 pp19840012531
- Optically coupled digital altitude encoder for general aviation altimetersAn optically coupled pressure altitude encoder which can be incorporated into commercially available inexpensive general aviation altimeters was successfully developed. The encoding of pressure altitude is accomplished in 100-ft (30.48-m) increments from -1000 to 20,000ft (-304.8 to 6096 m). The…30 pp19760007034
- Optimal Aircraft Control Upset Recovery With and Without Component FailuresThis paper treats the problem of recovering sustainable nondescending (safe) flight in a transport aircraft after one or more of its control effectors fail. Such recovery can be a challenging goal for many transport aircraft currently in the operational fleet for two reasons. First, they have very…6 pp
- Optimal cooperative control synthesis applied to a control-configured aircraftA multivariable control augmentation synthesis method is presented that is intended to enable the designer to directly optimize pilot opinion rating of the augmented system. The approach involves the simultaneous solution for the augmentation and predicted pilot's compensation via optimal control…35 ppNASA-CR-170411
- Optimal guidance and control for investigating aircraft noise-impact reductionA methodology for investigating the reduction of community noise impact is reported. This report is concerned with the development of two models to provide data: a guidance generator and an aircraft control generator suitable for various current and advanced types of aircraft. The guidance…59 ppNASA-TP-1237
- Optimal Input Design for Aircraft Stability and Control Flight TestingFlight testing to characterize aircraft stability and control is a complex and expensive task that involves restrictive practical constraints. Methods are examined for optimizing the inputs applied to aircraft controls during flight test maneuvers to produce informative flight data. Theory…28 pp
- Optimization of Supersonic Transport TrajectoriesThis paper develops a near-optimal guidance law for generating minimum fuel, time, or cost fixed-range trajectories for supersonic transport aircraft. The approach uses a choice of new state variables along with singular perturbation techniques to time-scale decouple the dynamic equations into…58 pp19980027605
- Optimization of Turbine Engine Cycle Analysis with Analytic DerivativesA new engine cycle analysis tool, called Pycycle, was recently built using the OpenMDAO framework. This tool uses equilibrium chemistry based thermodynamics, and provides analytic derivatives. This allows for stable and efficient use of gradient-based optimization and sensitivity analysis methods…11 ppGRC-E-DAA-TN32882
- Optimization of Turbine Engine Cycle Analysis with Analytic DerivativesA new engine cycle analysis tool, called Pycycle, was built using the OpenMDAO framework. Pycycle provides analytic derivatives allowing for an efficient use of gradient-based optimization methods on engine cycle models, without requiring the use of finite difference derivative approximation…11 ppGRC-E-DAA-TN32054
- Orbiter/shuttle carrier aircraft separation: Wind tunnel, simulation, and flight test overview and resultsA summary of the approach and landing test phase of the space shuttle program is given from the orbiter/shuttle carrier aircraft separation point of view. The data and analyses used during the wind tunnel testing, simulation, and flight test phases in preparation for the orbiter approach and…92 ppNASA-TM-58223
- Ordinates and Theoretical Pressure-Distribution Data for NACA 6- and 6A-Series Airfoil Sections with Thicknesses from 2 to 21 and From 2 to 15 Percent Chord, RespectivelyInformation is presented with which ordinates can be easily obtained for any thickness from 2 to 21 percent chord for NACA 63-, 64-, and 65-series airfoil sections and from 2 to 15 percent chord for NACA 63A-, 64-A, series airfoil sections. In addition, data required for estimation of the…88 ppNASA-TR-R-84
- Orion Abort Flight TestThe purpose of NASA's Constellation project is to create the new generation of spacecraft for human flight to the International Space Station in low-earth orbit, the lunar surface, as well as for use in future deep-space exploration. One portion of the Constellation program was the development of…31 ppDFRC-E-DAA-TN2272
- Output model-following control synthesis for an oblique-wing aircraftRecent interest in oblique-wing aircraft has focused on the potential aerodynamic performance advantage of a variable-skew oblique wing over a conventional or symmetric sweep wing. Unfortunately, the resulting asymmetric configuration has significant aerodynamic and inertial cross-coupling between…34 ppNASA-TM-100454
- Overflow Analysis of Unmanned Aircraft SystemsWith the increasing presence of unmanned aircraft systems (UAS), or drones, in the national airspace, the management for access and operation of these vehicles is required. NASA’s management approach is being developed under the unmanned aircraft system traffic management (UTM) program. To…14 pp20190000040
- Overview of a Comprehensive MD530F Acoustic Flight TestA cooperative flight test campaign between the US Army and NASA was performed. This test sought to characterize the acoustic emissions of a fully instrumented MD530F helicopter using a snapshot array and a phased array of microphones. The snapshot array of microphones aimed to provide even coverage…27 pp
- Overview of advanced wing designExamples of experiment theory correlation are presented to give an indication of the capabilities and limitations of wing design and analysis for transonic applications by potential flow theory. The examples include correlations of experimental pressure distributions with theoretical results from…13 pp19810010486
- Overview of external Nacelle drag and interference dragA historical view of multi-jet engine installations is given that emphasizes integration of the powerplant and the airframe in aircraft design for improved reduction in external nacelle drag and interference drag characteristics.10 pp19760003926
- Overview of FAA's aircraft icing programAn overview of the FAA's icing program is presented. The program involves certification of various types of aircraft for flight in known icing conditions, the study of icing conditions, and the preparation of certification standards. Test and technology transfer programs are also included.5 pp
- Overview of Fundamental High-Lift Research for Transport Aircraft at NASANASA has had a long history in fundamental and applied high lift research. Current programs provide a focus on the validation of technologies and tools that will enable extremely short take off and landing coupled with efficient cruise performance, simple flaps with flow control for improved…41 pp20070034167
- Overview of high performance aircraft propulsion researchThe overall scope of the NASA Lewis High Performance Aircraft Propulsion Research Program is presented. High performance fighter aircraft of interest include supersonic flights with such capabilities as short take off and vertical landing (STOVL) and/or high maneuverability. The NASA Lewis effort…17 pp19930002342
- Overview of Icing Research at NASA GlennThe aviation industry continues to deal with icing-related incidents and accidents on a regular basis. Air traffic continues to increase, placing more aircraft in adverse icing conditions more frequently and for longer periods. Icing conditions once considered rare or of little consequence, such as…36 ppGRC-E-DAA-TN7983
- Overview of Innovative Aircraft Power and Propulsion Systems and Their Applications for Planetary ExplorationPlanetary exploration may be enhanced by the use of aircraft for mobility. This paper reviews the development of aircraft for planetary exploration missions at NASA and reviews the power and propulsion options for planetary aircraft. Several advanced concepts for aircraft exploration, including the…22 pp20030068129
- Overview of NASA Electrified Aircraft Propulsion Research for Large Subsonic TransportsNASA is investing in Electrified Aircraft Propulsion (EAP) research as part of the portfolio to improve the fuel efficiency, emissions, and noise levels in commercial transport aircraft. Turboelectric, partially turboelectric, and hybrid electric propulsion systems are the primary EAP…25 pp20180000402
- Overview of NASA Electrified Aircraft Propulsion Research for Large Subsonic TransportsNASA is investing in Electrified Aircraft Propulsion (EAP) research as part of the portfolio to improve the fuel efficiency, emissions, and noise levels in commercial transport aircraft. Turboelectric, partially turboelectric, and hybrid electric propulsion systems are the primary EAP…27 pp20170012222
- Overview of NASA Electrified Aircraft Propulsion Research for Large Subsonic TransportsNASA is investing in Electrified Aircraft Propulsion (EAP) research as part of the portfolio to improve the fuel efficiency, emissions, and noise levels in commercial transport aircraft. Turboelectric, partially turboelectric, and hybrid electric propulsion systems are the primary EAP…25 pp20180000361
- Overview of NASA Electrified Aircraft Propulsion Research for Large Subsonic TransportsNASA is investing in Electrified Aircraft Propulsion (EAP) research as part of the portfolio to improve the fuel efficiency, emissions, and noise levels in commercial transport aircraft. Turboelectric, partially turboelectric, and hybrid electric propulsion systems are the primary EAP…20 pp20170006235
- Overview of NASA GRC Electrified Aircraft Propulsion Systems Analysis MethodsThe accurate modeling and analysis of electrified aircraft propulsion concepts require intricate subsystem system component coupling. The major challenge in electrified aircraft propulsion concept modeling lies in understanding how the subsystems "talk" to each other and the dependencies they have…23 pp20180001332
- Overview of Propulsion Systems for a Mars AircraftThe capabilities and performance of an aircraft depends greatly on the ability of the propulsion system to provide thrust. Since the beginning of powered flight, performance has increased in step with advancements in aircraft propulsion systems. These advances in technology from combustion engines…124 pp20010091338
- Overview of STOVL aircraft propulsion research offtakes and vertical lift systemsThe overall Short Takeoff and Vertical Landing (STOVL) Aircraft Propulsion Research program includes key technologies involving offtake systems, vertical lift systems, hot gas ingestion, STOVL augmentors, and integrated flight propulsion controls. A part of the NASA Lewis work involving STOVL…14 pp19940014880
- Overview of the Integrated Adaptive Wing Technology Maturation Wind-Tunnel Test ObjectivesThe Integrated Adaptive Wing Technology Maturation wind-tunnel test is the culmination of a cooperative effort between NASA and Boeing to develop control techniques that can improve the performance and safety of higher aspect ratio flexible transport aircraft. The wind-tunnel test article, to be…35 pp
- Overview of the Integrated Adaptive Wing Technology Maturation Wind-Tunnel Test ObjectivesThe Integrated Adaptive Wing Technology Maturation wind-tunnel test is the culmination of a cooperative effort between NASA and Boeing to develop control techniques that can improve the performance and safety of higher aspect ratio flexible transport aircraft. The wind-tunnel test article, to be…22 pp
- Overview of the Langley viscous drag reduction programAs a result of reductions in form drag and roughness drag, skin friction, drag, or viscous drag now represents a major contributor to the cruise drag of subsonic business and transport aircraft, and hence, is considered a barrier problem to further significant improvements in the aerodynamic…7 pp19880005564
- Oxide-dispersion-strengthened turbine blades. Volume 2The overall objective of Project 4 was to develop and test a high-temperature, uncooled gas turbine blade using MA6000 alloy. Production scale up of the MA6000 alloy was achieved with a fair degree of tolerance to non-optimum processing. The blade manufacturing process was also optimized. The…49 pp19890009116
- Parametric (On-Design) Cycle Analysis for a Separate-Exhaust Turbofan Engine With Interstage Turbine BurnerToday s modern aircraft is based on air-breathing jet propulsion systems, which use moving fluids as substances to transform energy carried by the fluids into power. Throughout aero-vehicle evolution, improvements have been made to the engine efficiency and pollutants reduction. The major…54 pp20050207442
- Parametric Inlet Tested in Glenn's 10- by 10-Foot Supersonic Wind TunnelThe Parametric Inlet is an innovative concept for the inlet of a gas-turbine propulsion system for supersonic aircraft. The concept approaches the performance of past inlet concepts, but with less mechanical complexity, lower weight, and greater aerodynamic stability and safety. Potential…3 pp20050217469
- Parametric Investigation of a High-Lift Airfoil at High Reynolds NumbersA new two-dimensional, three-element, advanced high-lift research airfoil has been tested in the NASA Langley Research Center s Low-Turbulence Pressure Tunnel at a chord Reynolds number up to 1.6 x 107. The components of this high-lift airfoil have been designed using a incompressible computational…37 pp20040110232
- Partial Measurements in Flight of the Flying Qualities of a Grumman XF7F-1 Airplane with a Modified Vertical TailPartial measurements in flight of the handling qualities of a Grumman XF7F-1 airplane were investigated. Results are for low altitude and normal center of gravity conditions only.20030063925
- Partially Turboelectric Aircraft Drive Key Performance ParametersThe purpose of this paper is to propose electric drive specific power, electric drive efficiency, and electrical propulsion fraction as the key performance parameters for a partially turboelectric aircraft power system and to investigate their impact on the overall aircraft performance. Breguet…11 pp20170006220
- Partially-Dressed Cavity-Closed Nose Landing Gear (PDCC-NLG) Problem: Experiment Description and ResultsThis talk describes the nose landing gear experiments in BART.23 ppNF1676L-10826
- Perceived Noise Analysis for Offset Jets Applied to Commercial Supersonic AircraftA systems analysis was performed with experimental jet noise data, engineaircraft performance codes and aircraft noise prediction codes to assess takeoff noise levels and mission range for conceptual supersonic commercial aircraft. A parametric study was done to identify viable engine cycles that…22 ppNASA/TM-2018-220049
- Perceived Noise Analysis for Offset Jets Applied to Commercial Supersonic AircraftA systems analysis was performed with experimental jet noise data, engine/aircraft performance codes and aircraft noise prediction codes to assess takeoff noise levels and mission range for conceptual supersonic commercial aircraft. A parametric study was done to identify viable engine cycles that…17 ppGRC-E-DAA-TN28940
- Perceived Noise Analysis for Offset Jets Applied to Commercial Supersonic AircraftA systems analysis was performed with experimental jet noise data, engine/aircraft performance codes and aircraft noise prediction codes to assess takeoff noise levels and mission range for conceptual supersonic commercial aircraft. A parametric study was done to identify viable engine cycles that…12 ppGRC-E-DAA-TN28452
- Perceptual Evaluation of Sound Exposure Level in Annoyance Ratings to Helicopter NoiseA psychoacoustic test was performed to assess the effectiveness of Sound Exposure Level (SEL) for indicating changes in annoyance to helicopter noise. SEL was evaluated for flyover auralizations of optimized rotor designs and for flyover recordings of different helicopters and maneuvers. The test…54 pp
- Performance analysis of flexible aircraft with active controlSmall perturbation equations of motion of a flexible aircraft with an active control technology (ACT) system were developed to evaluate the stability and performance of the controlled aircraft. The total aircraft system was formulated in state vector format and the system of equations was completed…10 pp
- Performance and loads data from a wind tunnel test of a full-scale, coaxial, hingeless rotor helicopterA full-scale XH-59A advancing blade concept helicopter was tested in Ames Research Center's 40 by 80 foot wind tunnel. The helicopter was tested with the rotor on and off, rotor hub fairings on and off, interrotor shaft fairing on and off, rotor instrumentation module on and off, and auxiliary…346 ppNASA-TM-81329
- Performance and rotor loads measurements of the Lynx XZ170 helicopter with rectangular bladesThis report presents the results of a series of flight tests on the Lynx XZ170 helicopter with rectangular blades. The test objectives were to explore the flight envelope and to measure the performance and structural loads of the Lynx main-rotor system. The tests were conducted as part of the…376 ppNASA-TM-104000
- Performance Characteristics of an Aircraft Engine with Exhaust Turbine Supercharger, Special ReportThe Pratt and Whitney Aircraft company and the Naval Aircraft Factory of the United States Navy cooperated in a laboratory and flight program of tests on an exhaust turbine supercharger. Two series of dynamometer tests of the engine super-charger combination were completed under simulated altitude…20090016337
- PERFORMANCE CHARACTERISTICS OF SEVERAL DIVERGENT-SHROUD AIRCRAFT EJECTORSPerformance characteristics of several divergent- shroud aircraft ejectors47 pp19630002632
- Performance degradation of a typical twin engine commuter type aircraft in measured natural icing conditionsThe performance of an aircraft in various measured icing conditions was investigated. Icing parameters such as liquid water content, temperature, cloud droplet sizes and distributions were measured continuously while in icing. Flight data were reduced to provide plots of the aircraft drag polars…30 ppNASA-TM-83564
- Performance deterioration based on existing (historical) data; JT9D jet engine diagnostics programThe results of the collection and analysis of historical data pertaining to the deterioration of JT9D engine performance are presented. The results of analyses of prerepair and postrepair engine test stand performance data from a number of airlines to establish the individual as well as average…225 ppNASA-CR-135448
- Performance deterioration based on in-service engine data: JT9D jet engine diagnostics programResults of analyses of engine performance deterioration trends and levels with respect to service usage are presented. Thirty-two JT9D-7A engines were selected for this purpose. The selection of this engine fleet provided the opportunity of obtaining engine performance data starting before the…178 ppNASA-CR-159525
- Performance of Advanced Heavy-Lift, High-Speed Rotorcraft ConfigurationsThe aerodynamic performance of rotorcraft designed for heavy-lift and high-speed cruise is examined. Configurations considered include the tiltrotor, the compound helicopter, and the lift-offset rotor. Design conditions are hover and 250-350 knot cruise, at 5k/ISA+20oC (civil) or 4k/95oF…28 pp20080047713
- Performance optimization of helicopter rotor bladesAs part of a center-wide activity at NASA Langley Research Center to develop multidisciplinary design procedures by accounting for discipline interactions, a performance design optimization procedure is developed. The procedure optimizes the aerodynamic performance of rotor blades by selecting the…24 ppNASA-TM-104054
- Performance, stability, and control characteristics at transonic speeds of three V/STOL airplane configurations with wings of variable sweepPerformance, stability, and control of three V/STOL variable-wing-sweep aircraft configurations at transonic speedsNASA-TM-X-321
- Periodic control of the individual-blade-control helicopter rotorResults of an investigation into methods of controller design for an individual helicopter rotor blade in the high forward-flight speed regime are described. This operating condition poses a unique control problem in that the perturbation equations of motion are linear with coefficients that vary…193 ppNASA-CR-166607
- Persistence Characteristics of Wind-Tunnel Pressure Signatures From Two Similar ModelsPressure signatures generated by two sonic-boom wind-tunnel models and measured at Mach 2 are presented, analyzed, and discussed. The two wind-tunnel models differed in length and span by a factor of fourteen, but were similar in wing-body planform shape. The geometry of the larger model had been…23 pp20040033375
- Perturbation solutions for the influence of forward flight on helicopter rotor flapping stabilityThe stability of the flapping motion of a helicopter rotor blade in forward flight is investigated, using a perturbation technique which gives analytic expressions for the eigenvalues, including the influence of the periodic aerodynamic forces in forward flight. The perturbation solutions are based…108 ppNASA-TM-X-62361
- PIFCGT: A PIF autopilot design program for general aviation aircraftThis report documents the PIFCGT computer program. In FORTRAN, PIFCGT is a computer design aid for determing Proportional-Integral-Filter (PIF) control laws for aircraft autopilots implemented with a Command Generator Tracker (CGT). The program uses Linear-Quadratic-Regulator synthesis algorithms…177 ppNASA-CR-166123
- Piloted Evaluation of Modernized Limited Authority Control Laws in the NASA-Ames Vertical Motion Simulator (VMS)The UH-60 BLACK HAWK was designed in the 1970s, when the US Army primarily operated during the day in good visual conditions. Subsequently, the introduction of night-vision goggles increased the BLACK HAWK'S mission effectiveness, but the accident rate also increased. The increased accident rate is…24 pp20030069038
- Piloted Flight Simulator Developed for Icing Effects TrainingIn an effort to expand pilot training methods to avoid icing-related accidents, the NASA Glenn Research Center and Bihrle Applied Research Inc. have developed the Ice Contamination Effects Flight Training Device (ICEFTD). ICEFTD simulates the flight characteristics of the NASA Twin Otter Icing…2 pp20050217468
- Piloted Simulation Assessment of the Impact of Flexible Structures on Handling Qualities of Generic Supersonic AircraftThe NASA Langley Research Center Cockpit Motion Facility (CMF) was used to conduct a piloted simulation assessment of the impact of flexible structures on flying qualities. The CMF was used because of its relatively high bandwidth, six degree-of-freedom motion capability. Previous studies assessed…18 pp20140002408
- Piloted-simulation study of effects of vortex flaps on low-speed handling qualities of a Delta-wing airplaneA piloted-simulation study was conducted to investigate the effects of vortex flaps on low-speed handling qualities of a delta-wing airplane. The simulation math model was developed from wind tunnel tests of a 0.15 scale model of the F-106B airplane. Pilot evaluations were conducted using a…38 pp19870017489
- Piloting Considerations for Terminal Area Operations of Civil Tiltwing and Tiltrotor AircraftThe existing body of research to investigate airworthiness, performance, handling, and operational requirements for STOL and V/STOL aircraft was reviewed for its applicability to the tiltrotor and tiltwing design concepts. The objective of this study was to help determine the needs for developing…18 ppNASA/CP-3220
- Pitch Control Margin at High Angle of Attack - Quantitative Requirements (Flight Test Correlation With Simulation Predictions)Aircraft designs that employ relaxed static stability (RSS) have the following problem: reduced pitching moments associated with RSS at high angle of attack (AOA) require a minimum pitch recovery moment or margin to guarantee a safe return from high AOA maneuvers at the most aft center of gravity…16 ppAIAA-92-4107
- Plans and Status of Wind-Tunnel Testing Employing an Aeroservoelastic Semispan ModelThis paper presents the research objectives, summarizes the pre-wind-tunnel-test experimental results to date, summarizes the analytical predictions to date, and outlines the wind-tunnel-test plans for an aeroservoelastic semispan wind-tunnel model. The model is referred to as the Supersonic…20 ppAIAA 2007-1770
- Pneumatic boot for helicopter rotor deicingPneumatic deicer boots for helicopter rotor blades were tested. The tests were conducted in the 6 by 9 ft icing research tunnel on a stationary section of a UH-IH helicopter main rotor blade. The boots were effective in removing ice and in reducing aerodynamic drag due to ice.20 pp
- Pneumatic system structure for circulation control aircraftA plenum for a circulation control rotor aircraft which surrounds the rotor drive shaft (18) and is so constructed that the top (32), outer (38) and bottom (36) walls through compressed air is admitted are fixed to aircraft structure and the inner wall (34) through which air passes to rotor blades…5 ppPatent Application Number: US-PATENT-APPL-SN-565433
- Positive displacement type general-aviation engines: Summary and concluding remarksThe activities of programs investigating various aspects of aircraft internal combustion engines are briefly described including developments in fuel injection technology, cooling systems and drag reduction, turbocharger technology, and stratified-charge rotary engines.2 pp19800013853
- Possible applications of soaring technology to drag reduction in powered general aviation aircraftA brief examination of the performance figures achieved by modern soaring machines and a little reflection on the often huge disparity in L/D values between sailplanes and GA aircraft indicates that careful attention to lessons learned in sailplane design and manufacture hold realistic promise for…22 pp19760003940
- Possible Mechanisms for Turbofan Engine Ice Crystal Icing at High AltitudeA thermodynamic model is presented to describe possible mechanisms of ice formation on unheated surfaces inside a turbofan engine compression system from fully glaciated ice crystal clouds often formed at high altitude near deep convective weather systems. It is shown from the analysis that…12 pp20150002337
- Possible Mechanisms for Turbofan Engine Ice Crystal Icing at High AltitudeA thermodynamic model is presented to describe possible mechanisms of ice formation on unheated surfaces inside a turbofan engine compression system from fully glaciated ice crystal clouds often formed at high altitude near deep convective weather systems. It is shown from the analysis that…20 pp20160011109
- Post-Flight Aerodynamic and Aerothermal Model Validation of a Supersonic Inflatable Aerodynamic DeceleratorNASA's Low Density Supersonic Decelerator Program is developing new technologies that will enable the landing of heavier payloads in low density environments, such as Mars. A recent flight experiment conducted high above the Hawaiian Islands has demonstrated the performance of several decelerator…18 ppARC-E-DAA-TN21795
- Post-Stall Aerodynamic Modeling and Gain-Scheduled Control DesignA multidisciplinary research e.ort that combines aerodynamic modeling and gain-scheduled control design for aircraft flight at post-stall conditions is described. The aerodynamic modeling uses a decambering approach for rapid prediction of post-stall aerodynamic characteristics of multiple-wing…15 ppAIAA Paper 2005-6169
- Potential for Landing Gear Noise Reduction on Advanced Aircraft ConfigurationsThe potential of significantly reducing aircraft landing gear noise is explored for aircraft configurations with engines installed above the wings or the fuselage. An innovative concept is studied that does not alter the main gear assembly itself but does shorten the main strut and integrates the…12 ppNF1676L-22681
- Power Requirements Determined for High-Power-Density Electric Motors for Electric Aircraft PropulsionFuture advanced aircraft fueled by hydrogen are being developed to use electric drive systems instead of gas turbine engines for propulsion. Current conventional electric motor power densities cannot match those of today s gas turbine aircraft engines. However, if significant technological advances…3 pp20050217395
- Powered-Lift Aerodynamics and AcousticsPowered lift technology is reviewed. Topics covered include: (1) high lift aerodynamics; (2) high speed and cruise aerodynamics; (3) acoustics; (4) propulsion aerodynamics and acoustics; (5) aerodynamic and acoustic loads; and (6) full-scale and flight research.487 pp19780016103
- Practical Application of a Subscale Transport Aircraft for Flight Research in Control Upset and Failure ConditionsOver the past decade, the goal of reducing the fatal accident rate of large transport aircraft has resulted in research aimed at the problem of aircraft loss-of-control. Starting in 1999, the NASA Aviation Safety Program initiated research that included vehicle dynamics modeling, system health…14 pp
- Practical Application of NASA-Langley Advanced Satellite Products to In-Flight Icing NowcastsExperimental satellite-based icing products developed by the NASA Langley Research Center provide new tools to identify the locations of icing and its intensity. Since 1997, research forecasters at the National Center for Atmospheric Research (NCAR) have been helping to guide the NASA Glenn…18 pp20060005178
- Practical Techniques for Modeling Gas Turbine Engine PerformanceThe cost and risk associated with the design and operation of gas turbine engine systems has led to an increasing dependence on mathematical models. In this paper, the fundamentals of engine simulation will be reviewed, an example performance analysis will be performed, and relationships useful for…20 ppGRC-E-DAA-TN33214
- Practical Techniques for Modeling Gas Turbine Engine PerformanceThe cost and risk associated with the design and operation of gas turbine engine systems has led to an increasing dependence on mathematical models. In this paper, the fundamentals of engine simulation will be reviewed, an example performance analysis will be performed, and relationships useful for…26 ppNASA/TM-2016-219147
- Pratt & Whitney Two Dimensional HSR Nozzle Test in the NASA Lewis 9- By 15- Foot Low Speed Wind Tunnel: Aerodynamic ResultsThis paper discusses a test that was conducted jointly by Pratt & Whitney Aircraft Engines and NASA Lewis Research Center. The test was conducted in NASA's 9- by 15-Foot Low Speed Wind Tunnel (9x15 LSWT). The test setup, methods, and aerodynamic results of this test are discussed. Acoustical…20 pp
- Precision Positional Data of General Aviation Air Traffic in Terminal Air SpaceThree dimensional radar tracks of general aviation air traffic at three uncontrolled airports are considered. Contained are data which describe the position-time histories, other derived parameters, and reference data for the approximately 1200 tracks. All information was correlated such that the…2,483 pp19780017105
- Predicted Aerodynamic Characteristics of a NACA 0015 Airfoil Having a 25% Integral-Type Trailing Edge FlapUsing the two-dimensional ARC2D Navier-Stokes flow solver analyses were conducted to predict the sectional aerodynamic characteristics of the flapped NACA-0015 airfoil section. To facilitate the analyses and the generation of the computational grids, the airfoil with the deflected trailing edge…168 ppNASA/CR-1999-209328
- Predicting Cost/Reliability/Maintainability of Advanced General Aviation Avionics EquipmentA methodology is provided for assisting NASA in estimating the cost, reliability, and maintenance (CRM) requirements for general avionics equipment operating in the 1980's. Practical problems of predicting these factors are examined. The usefulness and short comings of different approaches for…124 pp19810010585
- Predicting Noise From Aircraft Turbine-Engine CombustorsCOMBUSTOR and CNOISE are computer codes that predict far-field noise that originates in the combustors of modern aircraft turbine engines -- especially modern, low-gaseous-emission engines, the combustors of which sometimes generate several decibels more noise than do the combustors of older…1 pp20110014727
- Prediction of aircraft handling qualities using analytical models of the human pilotThe optimal control model (OCM) of the human pilot is applied to the study of aircraft handling qualities. Attention is focused primarily on longitudinal tasks. The modeling technique differs from previous applications of the OCM in that considerable effort is expended in simplifying the…16 pp19820016332
- Prediction of Landing Gear Noise Reduction and Comparison to MeasurementsNoise continues to be an ongoing problem for existing aircraft in flight and is projected to be a concern for next generation designs. During landing, when the engines are operating at reduced power, the noise from the airframe, of which landing gear noise is an important part, is equal to the…16 ppNF1676L-9665
- Prediction of pilot-aircraft stability boundaries and performance contoursControl-theoretic pilot models can provide important new insights regarding the stability and performance characteristics of the pilot-aircraft system. Optimal-control pilot models can be formed for a wide range of flight conditions, suggesting that the human pilot can maintain stability if he…8 pp
- Prediction of wing aeroelastic effects on aircraft lift and pitching moment characteristicsThe distribution of flight loads on an aircraft structure determines the lift and pitching moment characteristics of the aircraft. When the load distribution changes due to the aeroelastic response of the structure, the lift and pitching moment characteristics also change. Some estimate of the…26 ppNASA-TM-87631
- Preliminary Airfoil Design for Low Reynolds NumbersAdvances in the fields of electronics, batteries, and electric motors have enabled broad adoption of small-scale aircraft for various terrestrial applications. Numerous Micro Aerial Vehicles (MAVs) and small Unmanned Aerial Vehicles (UAVs), both civil and military, are in use today. Operation at…16 pp
- Preliminary analysis of effects of air cooling turbine blades on turbojet-engine performanceThe effects of turbine-blade cooling on engine performance were analytically investigated for a turbojet engine in which cooling air is bled from the engine compressor. The analysis was made for a constant turbine-inlet temperature and a range of altitudes to determine the minimum cooling…36 ppNACA-RM-E50E22
- Preliminary Assessment of Optimal Longitudinal-Mode Control for Drag Reduction through Distributed Aeroelastic ShapingThe emergence of advanced lightweight materials is resulting in a new generation of lighter, flexible, more-efficient airframes that are enabling concepts for active aeroelastic wing-shape control to achieve greater flight efficiency and increased safety margins. These elastically shaped aircraft…12 pp20140013229
- Preliminary design of a supersonic Short Takeoff and Vertical Landing (STOVL) fighter aircraftThe preliminary design study of a supersonic Short Takeoff and Vertical Landing (STOVL) fighter is presented. A brief historical survey of powered lift vehicles was presented, followed by a technology assessment of the latest supersonic STOVL engine cycles under consideration by industry and…422 pp19900014078
- Preliminary design of a supersonic Short-Takeoff and Vertical-Landing (STOVL) fighter aircraftA preliminary study of a supersonic short takeoff and vertical landing (STOVL) fighter is presented. Three configurations (a lift plus lift/cruise concept, a hybrid fan vectored thrust concept, and a mixed flow vectored thrust concept) were initially investigated with one configuration selected for…10 pp19910008852
- Preliminary design studies of an advanced general aviation aircraftThe preliminary design results are presented of the advanced aircraft design project. The goal was to take a revolutionary look into the design of a general aviation aircraft. Phase 1 of the project included the preliminary design of two configurations, a pusher, and a tractor. Phase 2 included the…204 pp19920010822
- Preliminary design studies of an advanced general aviation aircraftPreliminary design studies are presented for an advanced general aviation aircraft. Advanced guidance and display concepts, laminar flow, smart structures, fuselage and wing structural design and manufacturing, and preliminary configuration design are discussed. This project was conducted as a…12 pp19930020528
- Preliminary evaluation of flight-weight XRJ47-W-5 ram-jet engine at a Mach number of 2.75Free jet investigation of performance, burner shell cooling, liner durability, and ignition characteristics of ramjet engine conducted in altitude test chamber at inlet Mach number 2.7539 ppNACA-RM-E55G22
- Preliminary Evaluation of Turbine Performance with Variable-Area Turbine Nozzles in a Turbojet EngineThe performance of a two-stage turbine with variable-area first-stage turbine nozzles was determined in the NACA Lewis altitude wind tunnel over a range of simulated altitudes from 15,000 to 44,000 feet and engine speeds from 50 to 100 percent of rated speed. The variable-area turbine nozzles used…34 pp19930087512
- Preliminary Investigation in the NACA Low-Turbulence Tunnel of Low-drag Airfoil Sections Suitable for Admitting Air at the Leading EdgeAn investigation was carried out in the NACA low-turbulence tunnel to develop low-drag airfoil sections suitable for admitting air at the leading edge. A thickness distribution having the desired type of pressure distribution was found from tests of a flexible model. Other airfoil shapes were…39 ppNACA-WR-L-694
- Preliminary investigation of the control of a gas-turbine engine for a helicopter / Richard P. KrebsAn analog investigation of the power plant for a gas-turbine powered helicopter indicates that currently proposed turbine-propeller engine controls are satisfactory for helicopter application. Power increases from one-half to full rated at altitudes from sea level to 15,000 feet could be made in…15 ppNACA-RM-E51F19
- Preliminary Report on Laminar-Flow Airfoils and New Methods Adopted for Airfoil and Boundary-Layer InvestigationsRecent developments in airfoil-testing methods and fundamental air-flow investigations, as applied to airfoils, are discussed. Preliminary test results, obtained under conditions relatively free from stream turbulence and other disturbances, are presented. Suitable airfoils and airfoil-design…58 ppNACA-WR-L-345
- Preliminary Results From a Heavily Instrumented Engine Ice Crystal Icing Test in a Ground Based Altitude Test FacilityPreliminary results from the heavily instrumented ALF502R-5 engine test conducted in the NASA Glenn Research Center Propulsion Systems Laboratory are discussed. The effects of ice crystal icing on a full scale engine is examined and documented. This same model engine, serial number LF01, was used…28 ppNASA/TM-2016-219132
- Preliminary Results From a Heavily Instrumented Engine Ice Crystal Icing Test in a Ground Based Altitude Test FacilityPreliminary results from the heavily instrumented ALF502R-5 engine test conducted in the NASA Glenn Research Center Propulsion Systems Laboratory are discussed. The effects of ice crystal icing on a full scale engine is examined and documented. This same model engine, serial number LF01, was used…20 ppGRC-E-DAA-TN32441
- Preliminary Results From a Heavily Instrumented Engine Ice Crystal Icing Test in a Ground Based Altitude Test FacilityPreliminary results from the Heavily Instrumented ALF503R-5 Engine test conducted in the NASA Glenn Research Center Propulsion Systems Laboratory will be discussed. The effects of ice crystal icing on a full scale engine is examined and documented. This model engine, serial number LF01, was used…25 ppGRC-E-DAA-TN32978
- Preliminary Results of an Altitude-Wind-Tunnel Investigation of a TG-100A Gas Turbine-Propeller Engine: Compressor and Turbine Performance Characteristics - 4As part of an investigation of the performance and operational characteristics of the TG-100A gas turbine-propeller engine, conducted in the Cleveland altitude wind tunnel, the performance characteristics of the compressor and the turbine were obtained. The data presented were obtained at a…20030063965
- Preliminary Results of an Altitude-Wind-Tunnel Investigation of an Axial-Flow Gas Turbine-Propeller Engine: Compressor and Turbine Performance Characteristics - 4As part of an investigation of the performance and operational characteristics of the axial-flow gas turbine-propeller engine, conducted in the Cleveland altitude wind tunnel, the performance characteristics of the compressor and the turbine were obtained. The data presented were obtained at a…20030065929
- Preliminary results of boundary-layer noise measured on the x-15 airplaneBoundary layer noise measurements for X-15 aircraft at supersonic speeds13 pp19650025683
- Preliminary Results of British Nene II Engine Altitude-Chamber Performance Investigation. I - Altitude Performance Using Standard 18.75-Inch-Diameter Jet Nozzle: Altitude Performance Using Standard 18.75-Inch-Diameter Jet Nozzle - 1An investigation is being conducted to determine the altitude performance characteristics of the British Nene II engine and its components. The present paper presents the preliminary results obtained using a standard jet nozzle. The test results presented are for conditions simulating altitudes…46 ppNACA-RM-E8E12
- Preliminary Results of Nene II Engine Altitude-chamber Performance Investigation: Altitude Performance using 18.00-inch-diameter Jet Nozzle - 3An investigation is being conducted to determine the altitude performance characteristics of the Nene II engine and its components. The present paper presents the preliminary results obtained using jet nozzle 18.00 inches in diameter, with an area equal to 92.2 percent of the area of the standard…NACA-RM-E8H06
- Preliminary Results of Nene II Engine Altitude-chamber Performance Investigation: Altitude Performance using 18.41-inch Diameter-jet Nozzle - 2An investigation is being conducted to determine the altitude performance characteristics of the Nene II engine and its components. The present paper presents preliminary results obtained using a jet nozzle of 18.41 inches in diameter, giving an area equal to 96.4 percent of the area of the…43 ppNACA-RM-E8F14
- Preliminary sizing and performance of aircraftThe basic processes of a program that performs sizing operations on a baseline aircraft and determines their subsequent effects on aerodynamics, propulsion, weights, and mission performance are described. Input requirements are defined and output listings explained. Results obtained by applying the…115 pp19850023798
- Preliminary study of NAVSTAR/GPS for general aviationThe activities conducted as a planning effort to focus attention on the applicability of the global positioning system for general aviation are described. The description of GPS, its impact on economic and functional aspects of general aviation avionics, as well as a declaration of potential…82 pp19770006095
- Preliminary Study of Relationships between Stability and Control Characteristics and Affordability for High-Performance AircraftThis paper describes a study that is being done as part of the Methods for Affordable Design (MAD) program within the National Aeronautics and Space Administration (NASA), for which the goal is to develop design methods and information that contribute to reductions in the aircraft development cycle…14 ppAIAA-98-4265
- Preliminary study of VTO thrust requirements for a V/STOL aircraft with lift plus lift/cruise propulsionA preliminary assessment was made of the VTO thrust requirements for a supersonic (Type B) aircraft with a Lift plus Lift/Cruise propulsion system. A baseline aircraft with a takeoff gross weight (TOGW) of 13 608 kg (30,000 lb) was assumed. Pitch, roll, and yaw control thrusts (i.e., the thrusts…28 pp19800010833
- Preliminary Wind-Tunnel and Flight Tests of a Balanced Split Flap, Special ReportOne disadvantage that has been apparent in the operation of split flaps as used to date is the time and effort required to operate them. In this communication an investigation is being made of possible means for balancing them aerodynamically to make their operation easier. Several arrangements…11 pp20090015107
- Preliminary wind-tunnel investigation of an NACA 23012 airfoil with various arrangements of venetian-blind flapsReport presents the results of an investigation made in the NACA 7 by 10-foot wind tunnel of a large-chord NACA 23012 airfoil with several arrangements of venetian-blind flaps to determine the aerodynamic section characteristics as affected by the over-all flap chord, the chords of the slats used…16 ppNACA-TR-689
- Presentation of flight control design and handling quality commonality by separate surface stability augmentation for the family of commuter airplanesThe methodology and results for a flight control design and implementation for common handling qualities by Separate Surface Stability Augmentation (SSSA) for the family of commuter airplanes are contained. The open and closed loop dynamics and the design results of augmenting for common handling…49 pp19880010087
- Pressure distribution over an airfoil section with a flap and tabReport presents the results of wind tunnel tests made in the NACA 7 by 10-foot wind tunnel of a Clark Y airfoil with a flap and an inset tab. The pressures were measured on both the upper and lower surfaces at one chord section. Calculations were made of the normal-force and pitching-moment…18 ppNACA-TR-574
- Pressure distribution over an NACA 23012 airfoil with a fixed slot and a slotted flapReport presents the results of a pressure-distribution investigation conducted in the Langley Memorial Aeronautical Laboratory 7 by 10-foot wind tunnel to determine the air loads on an NACA 23012 airfoil in combination with a fixed leading-edge slot and a slotted flap. Pressures were measured over…14 ppNACA-TR-732
- Pressure distribution over an NACA 23012 airfoil with a slotted and a plain flapReport presents the results of pressure-distribution of an NACA 23012 airfoil equipped with a slotted flap and with a plain flap conducted in the 7 by 10-foot wind tunnel. A test installation was used in which the 7-foot-span airfoil was mounted vertically between the upper and lower sides of the…38 ppNACA-TR-633
- Pressure distribution over an NACA 23012 airfoil with an NACA 23012 external-airfoil flapReport presents the results of pressure-distribution tests of an NACA 23012 airfoil with an NACA 23012 external airfoil flap made in the 7 by 10-foot wind tunnel. The pressures were measured on the upper and lower surfaces at one chord section on both the main airfoil and on the flap for several…20 ppNACA-TR-614
- Pressure distribution over NACA 23012 airfoil with a slotted and a split flapA pressure-distribution investigation has been conducted in the NACA 4 by 6-foot vertical wind tunnel to determine the air loads on an NACA 23012 airfoil in combination with a 25.66-percent-chord slotted flap and a 20-percent-chord split flap. Pressures were measured on both the upper and the lower…26 ppNACA-TR-718
- Pressure distributions on a wing having NACA 4415 airfoil sections with trailing-edge flaps set at 0 deg and 40 degWind tunnel measurements of pressure distributions on wing having NACA 4415 airfoil sections with trailing-edge flaps set at 0 deg and 40 deg76 ppNASA-TM-X-2225
- Pressure-distribution investigation of an NACA 0009 airfoil with an 80-percent-chord plain flap and three tabsPressure-distribution tests of an NACA 0009 airfoil with an 80-percent-chord plain flap and three plain tabs, having chord of 10, 20, and 30 percent of the flap chord, were made. Section data suitable for application to the design of horizontal and vertical tail surfaces were obtained.…35 ppNACA-TN-761
- Pressure-distribution investigation on an NACA 0009 airfoil with a 30-percent-chord plain flap and three tabsPressure-distribution tests of an NACA 0009 airfoil with a 30-percent-chord plain flap and three plain tabs, having chords 10, 20, and 30 percent of the flap chord, were made. The purpose of these tests was to continue an investigation to supply structural and aerodynamic section data that may be…44 ppNACA-TN-759
- Probabilistic Design of a Wind Tunnel Model to Match the Response of a Full-Scale Aircraftapproach is presented for carrying out the reliability-based design of a plate-like wing that is part of a wind tunnel model. The goal is to design the wind tunnel model to match the stiffness characteristics of the wing box of a flight vehicle while satisfying strength-based risk/reliability…21 ppAIAA Paper 2005-2185
- Procedures for estimating the effects of design and operational characteristics of jet aircraft on ground noiseEstimation of design and operation effects on jet aircraft ground noise levels11 pp19690002237
- Proceedings of NASA Conference on Supersonic-Transport Feasibility Studies and Supporting ResearchSupersonic transport configurations, propulsion systems, structural materials, handling qualities, and sonic boom - conference506 ppNASA-TM-X-905
- Proceedings of the NASA, Industry, University, General Aviation Drag Reduction WorkshopThe conference on drag reduction research aims to improve general aviation aircraft performance.463 pp19760003909
- Proceedings of the Second NASA Aviation Safety Program Weather Accident Prevention ReviewThe Second NASA Aviation Safety Program (AvSP) Weather Accident Prevention (WxAP) Annual Project Review held June 5-7, 2001, in Cleveland, Ohio, presented the NASA technical plans and accomplishments to the aviation community. NASA-developed technologies presented included an Aviation Weather…819 ppNASA/CP-2003-210964
- Proceedings: Sixth Annual Workshop on Meteorological and Environmental Inputs to Aviation SystemsThe proceedings of a workshop on meteorological and environmental inputs to aviation systems held at The University of Tennessee Space Institute, Tullahoma, Tennessee. October 26 - 28, 1982, are reported. The workshop, jointly sponsored by NASA, NOAA, and FAA, brought together many disciplines of…151 pp19830025556
- Profile design for an advanced-technology airfoil for general aviation aircraftA profile from the NASA General Aviation Whitcomb series and NACA profiles are used as a starting point in designing an advanced airfoil for general aviation aircraft. Potential theory pressure distribution calculations, together with boundary layer calculations, permit a decrease in the null…27 pp19780024111
- Program user's manual for an unsteady helicopter rotor-fuselage aerodynamic analysisThe Rotor-Fuselage Analysis is a method of calculating the aerodynamic reaction between a helicopter rotor and fuselage. This manual describes the structure and operation of the computer programs that make up the Rotor-Fuselage Analysis, programs which prepare the input and programs which display…108 ppNASA-CR-181701
- Progress in aircraft gas turbine engine developmentAircraft gas turbine engine developments25 ppNASA-TM-X-52240
- Progress in Flaps Down Flight Reynolds Number Testing Techniques at the NTFA series of NASA/Boeing cooperative low speed wind tunnel tests was conducted in the National Transonic Facility (NTF) between 2003 and 2004 using a semi-span high lift model representative of the 777-200 aircraft. The objective of this work was to develop the capability to acquire high quality,…10 pp20070003726
- Progress of NASA research relating to noise alleviation of large subsonic jet aircraftConference on NASA research in noise reduction of subsonic jet aircraft - nacelle acoustic linings, sound generation in jet engines, and operational noise effects on humans691 pp19690002211
- Progress toward the development of an aircraft icing analysis capabilityAn overview of the NASA efforts to develop an aircraft icing analysis capability is presented. Discussions are included of the overall and long term objectives of the program as well as current capabilities and limitations of the various computer codes being developed. Descriptions are given of…42 pp19840012422
- Progress Toward the Development of an Airfoil Icing Analysis CapabilityThe NASA-Lewis aircraft icing analysis program is composed of three major sub-programs. These sub-programs are ice accretion simulation, performance degradation evaluation, and ice protection system evaluation. These topics cover all areas of concern related to the simulation of aircraft icing and…16 pp19910001553
- Progress Towards the Remote Sensing of Aircraft Icing HazardsNASA has teamed with the FAA, DoD, industry, and academia for research into the remote detection and measurement of atmospheric conditions leading to aircraft icing hazards. The ultimate goal of this effort is to provide pilots, controllers, and dispatchers sufficient information to allow aircraft…22 ppNASA/TM-2009-215828
- Propeller blockage research needsThe effect of mutual propeller/nacelle of fuselage interference on aircraft propulsive efficiency is studied in order to determine accurate drag levels from flight test data by accurately estimating installed thrust and drag and the resulting aircraft performance.3 pp19760003916
- Propeller-rotor whirl flutter - A state-of- the-art reviewPropeller rotor whirl flutter and instability in conventional and Vertical Takeoff and Landing /VTOL/ aircraft46 pp19660012890
- Propfan test assessment testbed aircraft flutter model test reportThe PropFan Test Assessment (PTA) program includes flight tests of a propfan power plant mounted on the left wind of a modified Gulfstream II testbed aircraft. A static balance boom is mounted on the right wing tip for lateral balance. Flutter analyses indicate that these installations reduce the…101 ppNASA-CR-179458
- Propfan test assessment testbed aircraft stability and control/performance 1/9-scale wind tunnel testsOne-ninth scale wind tunnel model tests of the Propfan Test Assessment (PTA) aircraft were performed in three different NASA facilities. Wing and propfan nacelle static pressures, model forces and moments, and flow field at the propfan plane were measured in these tests. Tests started in June 1985…160 ppNASA-CR-182121
- Propulsion challenges and opportunities for high-speed transport aircraftFor several years there was a growing interest in the subject of efficient sustained supersonic cruise technology applied to a high-speed transport aircraft. The major challenges confronting the propulsion community for supersonic transport (SST) applications are identified. Both past progress and…19 pp19880006427
- Propulsion Control Technology Development Needs to Address NASA Aeronautics Research Mission Goals for Thrusts 3a and 4The Commercial Aero-Propulsion Control Working Group (CAPCWG), consisting of propulsion control technology leads from The Boeing Company, GE Aviation, Honeywell, Pratt & Whitney, Rolls-Royce, and NASA (National Aeronautics and Space Administration) Glenn Research Center, has been working together…26 pp20180005340
- Propulsion Controlled Aircraft design and developmentThis paper describes the design, development, and ground testing of the propulsion controlled aircraft (PCA) flight control system. A backup flight control system which uses only engine thrust, the PCA system utilizes collective and differential thrust changes to steer an aircraft that experiences…23 pp19950026601
- Propulsion controlsIncreased system requirements and functional integration with the aircraft have placed an increased demand on control system capability and reliability. To provide these at an affordable cost and weight and because of the rapid advances in electronic technology, hydromechanical systems are being…11 pp19810003585
- Propulsion Health Monitoring for Enhanced SafetyThis report presents the results of the NASA contract Propulsion System Health Management for Enhanced Safety performed by General Electric Aircraft Engines (GE AE), General Electric Global Research (GE GR), and Pennsylvania State University Applied Research Laboratory (PSU ARL) under the NASA…79 ppNASA/CR-2003-212291
- Propulsion Investigation for Zero and Near-Zero Emissions AircraftAs world emissions are further scrutinized to identify areas for improvement, aviation s contribution to the problem can no longer be ignored. Previous studies for zero or near-zero emissions aircraft suggest aircraft and propulsion system sizes that would perform propulsion system and subsystems…30 pp20090023315
- Propulsion opportunities for future commuter aircraftCirca 1990 propulsion improvement concepts are discussed for 1000 to 5000 SHP conventional turboprop powerplants including engines, gearboxes, and propellers. Cycle selection, power plant configurations and advanced technology elements are defined and evaluated using average stage length DOC for…27 pp19820018422
- Propulsion Powertrain Real-Time Simulation Using Hardware-in-the-Loop (HIL) for Aircraft Electric Propulsion SystemIt is essential to design a propulsion powertrain real-time simulator using the hardware-in-the-loop (HIL) system that emulates an electrified aircraft propulsion (EAP) systems power grid. This simulator would enable us to facilitate in-depth understanding of the system principles, to validate…12 pp20170008460
- Propulsion Selection for 85kft Remotely Piloted Atmospheric Science AircraftThis paper describes how a 3 stage turbocharged gasoline engine was selected to power NASA's atmospheric science unmanned aircraft now under development. The airplane, whose purpose is to fly sampling instruments through targeted regions of the upper atmosphere at the exact location and time…20 pp19970004802
- Propulsion Study for Small Transport Aircraft Technology (STAT)Propulsion requirements were determined for 0.5 and 0.7 Mach aircraft. Sensitivity studies were conducted on both these aircraft to determine parametrically the influence of propulsion characteristics on aircraft size and direct operating cost (DOC). Candidate technology elements and design…187 pp19820002164
- Propulsion System Models for Rotorcraft Conceptual DesignThe conceptual design code NDARC (NASA Design and Analysis of Rotorcraft) was initially implemented to model conventional rotorcraft propulsion systems, consisting of turboshaft engines burning jet fuel, connected to one or more rotors through a mechanical transmission. The NDARC propulsion system…20 pp20140013079
- Propulsion system study for Small Transport Aircraft Technology (STAT)Propulsion system technologies applicable to the generation of commuter airline aircraft expected to enter service in the 1990's are identified and evaluated in terms of their impact on aircraft operating economics and fuel consumption. The most promising technologies in the areas of engine,…220 pp19810016543
- Propulsion-Airframe Integration Flight Test InstrumentationPresentation discusses existing instrumentation and potential investment areas for propulsion-airframe integration (PAI) flight test instrumentation.21 ppAFRC-E-DAA-TN57587
- Prospects and time tables for analytical estimation of the drag of complete aircraft configurationAnalytical drag methods and wind tunnel evaluation of aircraft design features are used to identify excessive drag of general aviation aircraft with reciprocating engines.3 pp19760003911
- Q-FANSTM for general aviation aircraftContinued growth of general aviation over the next 10 to 15 years is dependent on continuing improvement in aircraft safety, utility, performance and cost. Moreover, these advanced aircraft will need to conform to expected government regulations controlling propulsion system emissions and noise…267 ppNASA-CR-114665
- QCGAT aircraft/engine design for reduced noise and emissionsThe high bypass ratio QCGAT engine played an important role in shaping the aircraft design. The aircraft which evolved is a sleek, advanced design, six-place aircraft with 3538 kg (7,800 lb) maximum gross weight. It offers a 2778 kilometer (1500 nautical mile) range with cruise speed of 0.5 Mach…34 pp19800013844
- Quantifying Uncertainty of Landing and Takeoff Noise for Commercial Supersonic AircraftOf the many challenges faced by manufacturers attempting to offer supersonic travel to the public, the uncertainty in predicting the noise of these aircraft in airport operations has an immediate impact. No noise regulation exists in FAA or ICAO for certifying such aircraft, as these organization…22 pp
- Quiet Clean General Aviation Turbofan (QCGAT) technology study, volume 1The preliminary design of an engine which satisfies the requirements of a quiet, clean, general aviation turbofan (QCGAT) engine is described. Also an experimental program to demonstrate performance is suggested. The T700 QCGAT engine preliminary design indicates that it will radiate noise at the…191 pp19810013522
- Quiet engine program detailed engine designsEngine design constraints for optimal noise reduction of turbofan jet aircraft13 pp19690002228
- Quiet engine program preliminary engine design and aircraft integrationDesign considerations for integration of turbofan engine with reduced noise output in jet aircraft10 pp19690002227
- Ram-jet PerformanceThe ram jet is basically one of the most dimple types of aircraft engine. It consists only of an inlet diffuser, a combustion system, and an exit nozzle. A typical ram-jet configuration is shown in figure 128. The engine operates on the Brayton cycle, and ideal cycle efficiency depends only on the…55 pp
- Rating helicopter noiseThe effectiveness of the EPNL procedure in quantifying helicopter blade slap and tail rotor noise heard on approach some distance from the flyover position is addressed. Alternative methods of rating helicopter noise are reviewed including correction procedures to the EPNL concept which account for…19 pp
- Real-Time Adaptive Control Allocation Applied to a High Performance AircraftAbstract This paper presents the development and application of one approach to the control of aircraft with large numbers of control effectors. This approach, referred to as real-time adaptive control allocation, combines a nonlinear method for control allocation with actuator failure detection…11 pp
- Real-Time Aircraft Engine-Life MonitoringThis project developed an inservice life-monitoring system capable of predicting the remaining component and system life of aircraft engines. The embedded system provides real-time, inflight monitoring of the engine's thrust, exhaust gas temperature, efficiency, and the speed and time of operation.…1 pp20150005307
- Real-Time Cloud, Radiation, and Aircraft Icing Parameters from GOES over the USAA preliminary new, physically based method for realtime estimation of the probability of icing conditions has been demonstrated using merged GOES-10 and 12 data over the continental United States and southern Canada. The algorithm produces pixel-level cloud and radiation properties as well as an…6 ppPaper 7.1
- Real-time flutter analysis of an active flutter-suppression system on a remotely piloted research aircraftFlight flutter-test results of the first aeroelastic research wing (ARW-1) of NASA's drones for aerodynamic and structural testing program are presented. The flight-test operation and the implementation of the active flutter-suppression system are described as well as the software techniques used…24 pp19830010439
- Real-time flutter identificationThe techniques and a FORTRAN 77 MOdal Parameter IDentification (MOPID) computer program developed for identification of the frequencies and damping ratios of multiple flutter modes in real time are documented. Physically meaningful model parameterization was combined with state of the art recursive…155 pp19860002751
- Real-Time Stability and Control Derivative Extraction From F-15 Flight DataA real-time, frequency-domain, equation-error parameter identification (PID) technique was used to estimate stability and control derivatives from flight data. This technique is being studied to support adaptive control system concepts currently being developed by NASA (National Aeronautics and…36 ppNASA/TM-2003-212027
- Recent Advances in the LEWICE Icing ModelThis paper will describe two recent modifications to the Glenn ICE software. First, a capability for modeling ice crystals and mixed phase icing has been modified based on recent experimental data. Modifications have been made to the ice particle bouncing and erosion model. This capability has been…27 ppGRC-E-DAA-TN23449
- Recent developments in rotary-balance testing of fighter aircraft configurations at NASA Ames Research CenterTwo rotary balance apparatuses were developed for testing airplane models in a coning motion. A large scale apparatus, developed for use in the 12-Foot Pressure Wind tunnel primarily to permit testing at high Reynolds numbers, was recently used to investigate the aerodynamics of 0.05-scale model of…28 pp19850023777
- Recent Progress in V/STOL Aircraft TechnologyResults from wind tunnel and flight tests investigations for V/STOL aircraft are reviewed. Primary emphasis is given to technical results relating to three types of subsonic aircraft: a quiet STOL aircraft; a tilt rotor aircraft; and a turbofan V/STOL aircraft. Comparison and correlation between…16 ppNASA-TM-81281
- Recent Supersonic Transport ResearchFlight efficiency, stability and control, structures and materials, and operating problems of supersonic transport aircraft61 ppNASA-TM-X-54982
- Reduced Noise Gas Turbine Engine System and Supersonic Exhaust Nozzle System Using Elector to Entrain Ambient AirOne embodiment of the present invention is a unique gas turbine engine system. Another embodiment is a unique exhaust nozzle system for a gas turbine engine. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for gas turbine engine systems and exhaust…10 pp20170007237
- Reduced-Order Modeling and Parameter Estimation of Wind Tunnel Measurement SystemsWe present a method to develop a physics-based, reduced-order model of a wind tunnel measurement system (including a sting, strain gage force balance, and test article) to facilitate preliminary wind tunnel test design by predicting structural modes. This reduced-order model is combined with a…28 ppNASA/TM-20250008702
- Reduction of Aircraft Cruise Drag By Using Boundary Layer Heating To Minimize Fuselage Skin FrictionThe data reduction and results of the F-15B Flight Test Fixture experiment conducted at NASA Dryden are discussed. In addition, the feasibility of using the Orbital Sciences L-1011 was studied and a cost estimate prepared. Initial discussions have begun with Edwards Flight Research to explore the…87 pp19980004665
- Reduction of Background Noise in the NASA Ames 40- by 80-Foot Wind TunnelBackground noise in both open-jet and closed wind tunnels adversely affects the signal-to-noise ratio of acoustic measurements. To measure the noise of increasingly quieter aircraft models, the background noise will have to be reduced by physical means or through signal processing. In a closed wind…4 pp
- Reduction of high-speed impulsive noise by blade planform modification of a model helicopter rotorThe reduction of high speed impulsive noise for the UH-1H helicopter was investigated by using an advanced main rotor system. The advanced rotor system had a tapered blade planform compared with the rectangular planform of the standard rotor system. Models of both the advanced main rotor system and…60 ppNASA-TM-84553
- Reduction of profile drag by blowing out through peg holes in areas of streamline separation bubblesStreamline separation bubbles on aircraft profiles and fuselages were investigated. The additional drag was examined in relation to increased angle of incidence and unusually high wall sheer stress. A reduction of the separation bubble and a decrease in drag is obtained with pneumatic turbulators…19 pp19810019514
- Reduction of trimmed dragMethods are reported for reducing the aircraft drag coefficient for a given aircraft lift coefficient, or speed. The emphasis is placed in determining the load distribution between the wing-body combination and the tail which reduces overall drag coefficient. Furthermore, a technique is presented…12 pp19760003932
- Refined AFC-Enabled High-Lift System Integration StudyA prior trade study established the effectiveness of using Active Flow Control (AFC) for reducing the mechanical complexities associated with a modern high-lift system without sacrificing aerodynamic performance at low-speed flight conditions representative of takeoff and landing. The current…39 pp20160006410
- Remote Sensing of In-Flight Icing Conditions: Operational, Meteorological, and Technological ConsiderationsRemote-sensing systems that map aircraft icing conditions in the flight path from airports or aircraft would allow icing to be avoided and exited. Icing remote-sensing system development requires consideration of the operational environment, the meteorological environment, and the technology…76 pp20000034032
- Report on the test set-up for the structural testing of the Airmass Sunburst Ultralight AircraftThis report reviews the test set-up and procedure for the structural testing of the Airmass Sunburst Ultralight Aircraft. In general aviation today, there is a growing need for more stringent design criteria for ultralight aircraft. Unlike most general aviation aircraft, the ultralight lacks…5 pp19930020586
- Reports of Resilient Performance: Investigating Operators' Descriptions of Safety-producing Behaviors in the Aviation Safety Reporting SystemWhile many existing taxonomies and frameworks provide a common vocabulary for describing how human operators fail in the context of sociotechnical systems, at present, there is no common vocabulary to describe how humans succeed. Such a framework would facilitate systematically collecting and…9 pp
- Research and technology program perspectives for general aviation and commuter aircraftThe uses, benefits, and technology needs of the U.S. general aviation industry were studied in light of growing competition from foreign general aviation manufacturers, especially in the commuter and business jet aircraft markets.161 pp19830009183
- Research at NASA's NFAC wind tunnelsThe National Full-Scale Aerodynamics Complex (NFAC) is a unique combination of wind tunnels that allow the testing of aerodynamic and dynamic models at full or large scale. It can even accommodate actual aircraft with their engines running. Maintaining full-scale Reynolds numbers and testing with…10 pp19900016617
- Research needs in aircraft noise predictionProgress needed in understanding the mechanisms of aircraft noise generation and propagation is outlined using the focus provided by the need to predict accurately the noise produced and received at the ground by an aircraft operating in the vicinity of an airport. The components of internal engine…39 ppNASA-TM-X-72787
- Research requirements for development of improved helicopter rotor efficiencyThe research requirements for developing an improved-efficiency rotor for a civil helicopter are documented. The various design parameters affecting the hover and cruise efficiency of a rotor are surveyed, and the parameters capable of producing the greatest potential improvement are identified.…60 ppNASA-CR-145117
- Research turbine for high temperature core engine application. 1: Cold-airoverall performance of solid scaled turbineA solid, half-scale model of a 50.8-cm (20-in) research turbine designed for a high temperature core engine application was investigated over a range of speeds and pressure ratios. The results of this test are presented. The effect of rotor blade twist was also investigated. At the design…29 pp19740008589
- Resilient Propulsion Control Research for the NASA Integrated Resilient Aircraft Control (IRAC) ProjectGas turbine engines are designed to provide sufficient safety margins to guarantee robust operation with an exceptionally long life. However, engine performance requirements may be drastically altered during abnormal flight conditions or emergency maneuvers. In some situations, the conservative…14 pp20070030210
- Response of a turbojet and a piston-engine transport airplane to runway roughnessResponse of turbojet and piston engine transport aircraft to runway roughness35 pp19660003946
- Response-to-noise studies of some aircraft and spacecraft structuresFatigue and response to noise of aircraft and spacecraft viscoelastic panels, shell structure, and payloads21 ppNASA-TM-X-51739
- Results From F-18B Stability and Control Parameter Estimation Flight Tests at High Dynamic PressuresA maximum-likelihood output-error parameter estimation technique has been used to obtain stability and control derivatives for the NASA F-18B Systems Research Aircraft. This work has been performed to support flight testing of the active aeroelastic wing (AAW) F-18A project. The goal of this…143 ppNASA/TP-2000-209033
- Results of a landing gear loads test using a 0.0405-scale model (16-0) of the space shuttle orbiter in the Rockwell International NAAL wind tunnel (OA163), volume 1Experimental aerodynamic investigations were conducted on a sting mounted scale representation of the 140C outer mold line space shuttle orbiter configuration in the low speed wind tunnel. The primary test objectives were to define the orbiter landing gear system pressure loading and to record…437 ppNASA-CR-147611
- Results of an A109 simulation validation and handling qualities studyThe results for the validation of a mathematical model of the Agusta A109 helicopter, and subsequent use of the model as the baseline for a handling qualities study of cockpit centerstick requirements, are described. The technical approach included flight test, non-realtime analysis, and realtime…29 pp19890014952
- Results of an experimental program investigating the effects of simulated ice on the performance of the NACA 63A415 airfoil with flapAerodynamic data from a test program in the Icing Research Tunnel are reported for a NACA 63A415 airfoil, with fowler flap, clean and with simulated ice shapes. The effect of three ice shapes on airfoil performance are presented, two of the simulated ice shapes are from earlier Icing Tunnel tests.…188 ppNASA-CR-168288
- Results of design studies and wind tunnel tests of an advanced high lift system for an Energy Efficient TransportThe development of an advanced technology high lift system for an energy efficient transport incorporating a high aspect ratio supercritical wing is described. This development is based on the results of trade studies to select the high lift system, analysis techniques utilized to design the high…373 ppNASA-CR-159389
- Results of NASA/DARPA Automatic Probe and Drogue Refueling Flight TestThis presentation reports the results of the NASA/DARPA automatic probe and drogue refueling flight test. The program met several of its objectives including the design, development and successful testing of a prototype system to autonomously perform probes to drogue refueling; demonstrated…23 pp20080013250
- Resume of Handling Qualities of the X-15 AirplaneX-15 aircraft handling qualities and longitudinal stability and control during launch, climbout, semiballistic flight, atmosphere entry, and landing20 pp19650014322
- Reverse Engineering Crosswind Limits - A New Flight Test Technique?During modification of a Gulfstream III test bed aircraft for an experimental flap project, all roll spoiler hardware had to be removed to accommodate the test article. In addition to evaluating the effects on performance and flying qualities resulting from the modification, the test team had to…38 ppDFRC-E-DAA-TN11330
- Review of aircraft noise propagationThe current state of knowledge about the propagation of aircraft noise was reviewed. The literature on the subject is surveyed and methods for predicting the most important and best understood propagation effects are presented. Available empirical data are examined and the data's general validity…60 pp19750024046
- Review of jet engine emissionsA review of the emission characteristics of jet engines is presented. The sources and concentrations of the various constituents in the engine exhaust and the influence of engine operating conditions on emissions are discussed. Cruise emissions to be expected from supersonic engines are compared…18 ppNASA-TM-X-68064
- Review of propulsion-induced effects on aerodynamics of jet V/STOL aircraftPropulsion device-induced effects on V/STOL aircraft aerodynamics in hover and transition flight70 pp19700008938
- Reynolds Number Effects on the Stability and Control Characteristics of a Supersonic TransportA High Speed Civil Transport (HSCT) configuration was tested in the National Transonic Facility at the NASA Langley Research Center as part of NASA's High Speed Research Program. A series of tests included longitudinal and lateral/directional studies at transonic and low speed, high-lift conditions…24 ppAIAA Paper 2002-0417
- Reynolds-Stress Budgets in an Impinging Shock Wave/Boundary-Layer InteractionImplicit large-eddy simulation (ILES) of a shock wave/boundary-layer interaction (SBLI) was performed. Comparisons with experimental data showed a sensitivity of the current prediction to the modeling of the sidewalls. This was found to be common among various computational studies in the…25 pp20180001494
- Riblets for aircraft skin-friction reductionEnergy conservation and aerodynamic efficiency are the driving forces behind research into methods to reduce turbulent skin friction drag on aircraft fuselages. Fuselage skin friction reductions as small as 10 percent provide the potential for a 250 million dollar per year fuel savings for the…15 pp19880005573
- Ride quality sensitivity to SAS control law and to handling quality variationsThe RQ trends which large flexible aircraft exhibit under various parameterizations of control laws and handling qualities are discussed. A summary of the assumptions and solution technique, a control law parameterization review, a discussion of ride sensitivity to handling qualities, and the RQ…15 pp19760019101
- Riding and handling qualities of light aircraft: A review and analysisDesign procedures and supporting data necessary for configuring light aircraft to obtain desired responses to pilot commands and gusts are presented. The procedures employ specializations of modern military and jet transport practice where these provide an improvement over earlier practice. General…412 pp19720018355
- Robust nonlinear control of vectored thrust aircraftAn interdisciplinary program in robust control for nonlinear systems with applications to a variety of engineering problems is outlined. Major emphasis will be placed on flight control, with both experimental and analytical studies. This program builds on recent new results in control theory for…44 ppNASA-CR-192727
- Roles, uses, and benefits of general aviation aircraft in aerospace engineering educationMany colleges and universities throughout the United States offer outstanding programs in aerospace engineering. In addition to the fundamentals of aerodynamics, propulsion, flight dynamics, and air vehicle design, many of the best programs have in the past provided students the opportunity to…15 pp19940019627
- Rotary Balance Wind Tunnel Testing for the FASER Flight Research AircraftFlight dynamics research was conducted to collect and analyze rotary balance wind tunnel test data in order to improve the aerodynamic simulation and modeling of a low-cost small unmanned aircraft called FASER (Free-flying Aircraft for Sub-scale Experimental Research). The impetus for using FASER…17 ppAIAA Paper 2016-3105
- Rotating Shake Test and Modal Analysis of a Model Helicopter Rotor BladeRotating blade frequencies for a model generic helicopter rotor blade mounted on an articulated hub were experimentally determined. Testing was conducted using the Aeroelastic Rotor Experimental System (ARES) testbed in the Helicopter Hover Facility (HBF) at Langley Research Center. The measured…20 ppNASA-TM-4760
- Rotor aeroelastic stability coupled with helicopter body motionA 5.5-foot-diameter, soft-in-plane, hingeless-rotor system was tested on a gimbal which allowed the helicopter rigid-body pitch and roll motions. Coupled rotor/airframe aeroelastic stability boundaries were explored and the modal damping ratios were measured. The time histories were correlated with…10 pp
- Rotor performance characteristics from an aeroacoustic helicopter wind-tunnel test programAn investigation of helicopter rotor noise at model scale was conducted in the Langley 4 by 7 meter tunnel. The program described was the first of a planned three-phase project whose purpose was to examine the characteristic noise mechanism involved in main rotor/tail rotor interaction noise. This…100 ppNASA-TM-87661
- Rotor Performance Predictions of a Next Generation Mars Science HelicopterSince Ingenuity took flight and proved aerial capabilities on Mars, the horizon for rotorcraft on the Red Planet has only expanded. One proposed future Martian rotorcraft is the Mars Science Helicopter (MSH). The MSH is a hexacopter capable of carrying scientific payloads. As a part of its joint…17 pp
- Rotorcraft aeroelastic stabilityTheoretical and experimental developments in the aeroelastic and aeromechanical stability of helicopters and tilt-rotor aircraft are addressed. Included are the underlying nonlinear structural mechanics of slender rotating beams, necessary for accurate modeling of elastic cantilever rotor blades,…177 pp
- Rotorcraft Flight Dynamics and Controls Research at NASAIn recent years, NASA has invested in key activities in the areas of flight controls, handling qualities and operations of rotorcraft for civilian applications. More specifically, the flight dynamics and control discipline has focused on analyzing the unique flight control and handling qualities…15 pp20190025895
- Rotorcraft Flight Dynamics and Controls Research at NASAIn recent years, NASA has invested in key activities in the areas of flight controls, handling qualities and operations of rotorcraft for civilian applications. More specifically, the flight dynamics and control discipline has focused on analyzing the unique flight control and handling qualities…15 pp20190027087
- Rotorcraft handling-qualities design criteria developmentJoint NASA/Army efforts at the Ames Research Center to develop rotorcraft handling-qualities design criteria began in earnest in 1975. Notable results were the UH-1H VSTOLAND variable stability helicopter, the VFA-2 camera-and-terrain-board simulator visual system, and the generic helicopter…51 pp19880007262
- Rotorcraft Optimization Tools: Incorporating Rotorcraft Design Codes into Multi-Disciplinary Design, Analysis, and OptimizationOne of the goals of NASA's Revolutionary Vertical Lift Technology Project (RVLT) is to provide validated tools for multidisciplinary design, analysis and optimization (MDAO) of vertical lift vehicles. As part of this effort, the software package, RotorCraft Optimization Tools (RCOTOOLS), is being…17 pp20180000894
- Roughness effects on boundary-layer transition for blunt-leading-edge plates at Mach 6Effects of controlled roughness on boundary layer transition for upswept blunted plates in free stream42 pp19660023725
- RSRA sixth scale wind tunnel testThe sixth scale model of the Sikorsky/NASA/Army rotor systems research aircraft was tested in an 18-foot section of a large subsonic wind tunnel for the purpose of obtaining basic data in the areas of performance, stability, and body surface loads. The model was mounted in the tunnel on the struts…713 ppNASA-CR-144964
- RSRA sixth scale wind tunnel test. Tabulated balance data, volume 2Summaries are presented of all the force and moment data acquired during the RSRA Sixth Scale Wind Tunnel Test. These data include and supplement the data presented in curve form in previous reports. Each summary includes the model configuration, wing and empennage incidences and deflections, and…1,002 ppNASA-CR-144965
- Runway Incursion Prevention for General Aviation OperationsA Runway Incursion Prevention System (RIPS) and additional incursion detection algorithm were adapted for general aviation operations and evaluated in a simulation study at the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC) in the fall of 2005. RIPS has been…12 pp
- Runway Incursion Prevention System for General Aviation OperationsA Runway Incursion Prevention System (RIPS) and additional incursion detection algorithm were adapted for general aviation operations and evaluated in a simulation study at the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC) in the fall of 2005. RIPS has been…12 ppLF99-3305
- SafeAeroBERT: Towards a Safety-Informed Aerospace-Specific Language ModelAs aviation systems continue to operate with high traffic, large amounts of documents containing safety-relevant data continue to be generated via reporting systems such as the Aviation Safety Reporting System (ASRS). Advanced natural language processing techniques, specifically pre-trained…14 pp
- SafeAeroBERT: Towards a Safety-Informed Aerospace-Specific Language ModelAs aviation systems continue to operate with high traffic, large amounts of documents containing safety-relevant data continue to be generated via reporting systems such as the ASRS. Advanced natural language processing techniques, specifically pre-trained language models, have shown great success…9 ppAIAA-2023-3437
- Scale and Turbulence Effects on the Lift and Drag Characteristics of the NACA 65(Sub 3)-418, A=1.0 Airfoil SectionWind-tunnel tests, investigating low drag wing performance in small-scale tests, showed a large increase in minimum drag coefficient, and a decrease of maximum lift coefficient occurred with decreasing Reynolds Number above certain designated values. The lift-curve slope varied up to 6% between…25 ppNACA-ACR-L4H11
- Scale Effect on Clark Y Airfoil Characteristics from NACA Full-Scale Wind-Tunnel TestsThis report presents the results of wind tunnel tests conducted to determine the aerodynamic characteristics of the Clark Y airfoil over a large range of Reynolds numbers. Three airfoils of aspect ratio 6 and with 4, 6, and 8 foot chords were tested at velocities between 25 and 118 miles per hour,…18 ppNACA-TR-502
- Scale-effect tests in a turbulent tunnel of the NACA 65(sub 3)-418, a = 1.0 airfoil section with 0.20-airfoil-chord split flap22 ppNACA-ACR-L4I22
- Scaling Evaluation of Ice-Crystal Icing on a Modern Turbofan Engine in PSL Using the COMDES-MELT CodeThis paper presents preliminary ice-crystal icing (ICI) altitude scaling evaluation results of a Honeywell Uncertified Research Engine (HURE) that was tested in the NASA Glenn Research Center Propulsion Systems Laboratory (PSL) during January of 2018. This engine geometry features a hidden core…9 pp20190026535
- Scaling Methods for Simulating Aircraft In-Flight Icing EncountersThis paper discusses scaling methods which permit the use of subscale models in icing wind tunnels to simulate natural flight in icing. Natural icing conditions exist when air temperatures are below freezing but cloud water droplets are super-cooled liquid. Aircraft flying through such clouds are…18 ppNASA-TM-107538
- SCAR arrow-wing active flutter suppression systemThe potential performance and direct operating cost benefits of an active flutter suppression system (FSS) for the NASA arrow-wing supersonic cruise configuration were determined. A FSS designed to increase the flutter speed of the baseline airplane 20 percent. A comparison was made of the…137 pp19770015202
- Screening of Potential Landing Gear Noise Control Devices at Virginia Tech For QTD II Flight TestIn support of the QTD II (Quiet Technology Demonstrator) program, aeroacoustic measurements of a 26%-scale, Boeing 777 main landing gear model were conducted in the Virginia Tech Stability Tunnel. The objective of these measurements was to perform risk mitigation studies on noise control devices…13 ppAIAA Paper No. 2007-3455
- Seeing Shock Waves: Background Oriented Schlieren for Flight TestBOS for flight test focusing on aircraft operations and piloting.31 ppAFRC-E-DAA-TN43978
- Selected bibliography of NACA-NASA aircraft icing publicationsA summary of NACA-NASA icing research from 1940 to 1962 is presented. It includes: the main results of the NACA icing program from 1940 to 1950; a selected bibliography of 132 NACA-NASA aircraft icing publications; a technical summary of each document cited in the selected bibliography; and a…128 ppNASA-TM-81651
- Selected Examples of NACA/NASA Supersonic Flight ResearchThe present Dryden Flight Research Center, a part of the National Aeronautics and Space Administration, has a flight research history that extends back to the mid-1940's. The parent organization was a part of the National Advisory Committee for Aeronautics and was formed in 1946 as the Muroc Flight…68 ppNASA-SP-513
- Selected Flight Test Results for Online Learning Neural Network-Based Flight Control SystemThe NASA F-15 Intelligent Flight Control System project team developed a series of flight control concepts designed to demonstrate neural network-based adaptive controller benefits, with the objective to develop and flight-test control systems using neural network technology to optimize aircraft…17 pp20050196721
- Sensor Selection for Aircraft Engine Performance Estimation and Gas Path Fault DiagnosticsThis paper presents analytical techniques for aiding system designers in making aircraft engine health management sensor selection decisions. The presented techniques, which are based on linear estimation and probability theory, are tailored for gas turbine engine performance estimation and gas…18 pp20150019480
- Sensor Selection for Aircraft Engine Performance Estimation and Gas Path Fault DiagnosticsThis paper presents analytical techniques for aiding system designers in making aircraft engine health management sensor selection decisions. The presented techniques, which are based on linear estimation and probability theory, are tailored for gas turbine engine performance estimation and gas…12 pp20150022392
- Separation of Vortex Shedding Tones and Broadband Signals using SPOD of uPSP Measurements in NASA Ames Wind Tunnel Test12 pp
- Shake Test Results and Dynamic Characterization of the Large Rotor Test Apparatus in the NFAC 40- by 80-Foot Wind TunnelPrior to the full-scale wind tunnel test of the UH-60A Airloads rotor, a shake test was completed on the Large Rotor Test Apparatus. The goal of the shake test was to characterize the oscillatory response of the test rig and provide a dynamic calibration of the balance to permit accurate…42 ppNASA/TM-2015-218877
- Simplified procedures for estimating flapwise bending moments on helicopter rotor blades. Part 1 - Procedures and chartsEstimation of flapwise bending moments on helicopter rotor blades463 ppNASA-CR-1440-PT-1
- Simplified procedures for estimating flapwise bending moments on helicopter rotor blades. Part 2 - TablesTabulated bending moment transfer coefficients for helicopter rotor blades94 ppNASA-CR-1441
- Simulated Altitude Performance of Combustors for the 24C Jet Engine: 24C-4 Combustor - 2The performance of a 24C-4 combustor was investigated with three different combustor baskets and five modifications of these baskets at conditions simulating static (zero-ram) operation of the 24C jet engine over ranges of altitude and engine speed to determine and improve the altitude operational…48 ppNACA-RM-SE7J06
- Simulated rotor test apparatus dynamic characteristics in the 80- by 120-foot wind tunnelA shake test was conducted in the 80 by 120 foot Wind Tunnel at NASA Ames Research Center, using a load frame and dummy weights to simulate the weight of the NASA Rotor Test Apparatus. The simulated hub was excited with broadband random excitation, and accelerometer responses were measured at…26 ppNASA-TM-102870
- Simulation Model Development for Icing Effects Flight TrainingA high-fidelity simulation model for icing effects flight training was developed from wind tunnel data for the DeHavilland DHC-6 Twin Otter aircraft. First, a flight model of the un-iced airplane was developed and then modifications were generated to model the icing conditions. The models were…22 pp20030055623
- Simulation model of the integrated flight/propulsion control system, displays, and propulsion system for ASTOVL lift-fan aircraftA simulation model has been developed for use in piloted evaluations of takeoff, transition, hover, and landing characteristics of an advanced, short takeoff, vertical landing lift fan fighter aircraft. The flight/propulsion control system includes modes for several response types which are coupled…50 pp19950019992
- Simulation of three supersonic transport configurations with the Boeing 367-80 in-flight dynamic simulation airplaneIn-flight dynamic simulator used to evaluate problems of low-speed approach and landing of supersonic transport219 ppNASA-CR-66125
- Simulation of X-38 Landing Scenarios With Landing Gear FailuresAbnormal landing scenarios of the X-38 prototype Crew Rescue Vehicle (CRV) were modeled for three different cases involving non-deployment of landing gear with an explicit dynamic nonlinear finite element code, MSC/DYTRAN. The goal of this research was to develop models to predict the probability…41 ppNASA/TM-2000-210078
- Simulation Tools Model Icing for Aircraft DesignHere s a simple science experiment to try: Place an unopened bottle of distilled water in your freezer. After 2-3 hours, if the water is pure enough, you will notice that it has not frozen. Carefully pour the water into a bowl with a piece of ice in it. When it strikes the ice, the water will…2 pp
- Simulation-Based Assessment of a Full-Scale Installed Quiet Landing GearFull-scale simulations of a Gulfstream G-III aircraft, performed in support of the NASA Acoustic Research Measurements flights, are presented to complement results discussed in earlier studies. The flow solver employed in those studies, Dassault Systèmes’ lattice Boltzmann PowerFLOW®, was also used…16 ppNF1676L-31518
- Simulator Evaluation of Runway Incursion Prevention Technology for General Aviation OperationsA Runway Incursion Prevention System (RIPS) has been designed under previous research to enhance airport surface operations situation awareness and provide cockpit alerts of potential runway conflict, during transport aircraft category operations, in order to prevent runway incidents while also…86 pp20110005513
- Simulator study of conventional general aviation instrument displays in path-following tasks with emphasis on pilot-induced oscillationsA study of the use of conventional general aviation instruments by general aviation pilots in a six degree of freedom, fixed base simulator was conducted. The tasks performed were tracking a VOR radial and making an ILS approach to landing. A special feature of the tests was that the sensitivity of…56 pp19810006482
- Simulator study of coupled roll-spiral mode effects on lateral-directional handling qualitiesSimulator study of coupled roll-spiral mode effects on lateral-directional handling qualities48 pp19700011188
- Simulator study of the low-speed handling qualities of a supersonic cruise arrow-wing transport configuration during approach and landingA fixed-based simulator study was conducted to determine the low-speed flight characteristics of an advanced supersonic cruise transport having an arrow wing, a horizontal tail, and four dry turbojets with variable geometry turbines. The primary piloting task was the approach and landing. The…34 pp19770011064
- Single-Lever Power Control for General Aviation Aircraft Promises Improved Efficiency and Simplified Pilot ControlsGeneral aviation research is leading to major advances in internal combustion engine control systems for single-engine, single-pilot aircraft. These advances promise to increase engine performance and fuel efficiency while substantially reducing pilot workload and increasing flight safety. One such…3 pp
- Small Airframe Manufacturer's Icing PerspectiveThis viewgraph presentation describes the icing effects, risk mitigation practices, and icing certifications for various Cessna small aircraft models. NASA's role in the development of simulation tools for icing certifications is also discussed.29 pp
- Small Engine Component Technology (SECT)A study of small gas turbine engines was conducted to identify high payoff technologies for year-2000 engines and to define companion technology plans. The study addressed engines in the 186 to 746 KW (250 to 1000 shp) or equivalent thrust range for rotorcraft, commuter (turboprop), cruise missile…455 pp19910014892
- Small engine components test facility turbine testing cellNASA Lewis Research Center has designed and constructed a new state-of-the-art test facility. This facility, called the Small Engine Components Test Facility (SECTF), is used to test gas turbines and compressors at conditions similar to actual engine conditions. The SECTF is comprised of two…17 pp19880012653
- Small gas turbine engine technologyPerformance of small gas turbine engines in the 250 to 1,000 horsepower size range is significantly lower than that of large engines. Engines of this size are typically used in rotorcraft, commutercraft, general aviation, and cruise missile applications. Principal reasons for the lower efficiencies…39 pp19880007255
- Small Propeller and Rotor Testing Capabilities of the NASA Langley Low Speed Aeroacoustic Wind TunnelThe Low Speed Aeroacoustic Wind Tunnel (LSAWT) at NASA Langley Research Center has recently undergone a configuration change. This change incorporates an inlet nozzle extension meant to serve the dual purposes of achieving lower free-stream velocities as well as a larger core flow region. The…17 pp20170005862
- Small UAV Automatic Ground Collision Avoidance System Design Considerations and Flight Test ResultsThe National Aeronautics and Space Administration (NASA) Armstrong Flight Research Center Small Unmanned Aerial Vehicle (SUAV) Automatic Ground Collision Avoidance System (Auto GCAS) project demonstrated several important collision avoidance technologies. First, the SUAV Auto GCAS design included…135 pp20150014106
- Small V/STOL aircraft analysis, volume 1A study has been made of the economic viability of advanced V/STOL aircraft concepts in performing general aviation missions. A survey of general aviation aircraft users, operators, and manufacturers indicated that personnel transport missions formulated around business executive needs, commuter…93 pp19740020391
- Small V/STOL aircraft analysis. Volume 2: AppendicesA survey of general aviation activities in the United States was principally conducted through interviews with users, manufacturers, trade associations, and government organizations. A list of the organizations interviews is presented. The data became the basis for defining the current and future…94 pp19740001933
- SMART Rotor Development and Wind-Tunnel TestBoeing and a team from Air Force, NASA, Army, Massachusetts Institute of Technology, University of California at Los Angeles, and University of Maryland have successfully completed a wind-tunnel test of the smart material actuated rotor technology (SMART) rotor in the 40- by 80-foot wind-tunnel of…23 ppARC-E-DAA-TN453
- SMART Rotor Wind Tunnel Test ReportThe Boeing Company, Mesa Arizona, has been developing smart material actuated rotor technology (SMART) under in-house, DARPA (Defense Advanced Research Projects Agency), NASA and Army funding. A whirl tower test of the SMART active flap rotor system was successfully conducted at the remote test…71 ppNASA/CR-2015-219075
- Software Defined Wireless Avionics for Flight TestWireless avionics could revolutionize current flight systems by reducing nonrecurring engineering, providing a means to rapidly develop and implement flight systems, and providing unprecedented insight into vehicle health, maintenance, and performance. Despite these benefits, there is still a…16 pp20180008673
- Solar Brayton engine/alternator setWork on the Mod O solar Brayton engine/alternator set is redirected to utilize solarized components of the automotive advanced gas turbine (AGT). The new configuration is referred to as the Mod I. Commercialization of solar Brayton engines thus should be enhanced not only by relating the design to…13 pp
- Solid State Energy Harvesting and Power Conversion in Gas Turbine EnginesOverview: Solid state energy harvesting using waste heat available in gas turbine engine offers potential for power generation to meet growing power needs of aircraft; Thermoelectric material advances offer new opportunities; Weight-optimized integrated turbine engine structure incorporating energy…25 pp20180004325
- Some comments on fuselage dragThe following areas relating to fuselage drag are considered: (1) fuselage fineness - ratio and why and how this can be selected during preliminary design; (2) windshield drag; (3) skin roughness; and (4) research needs in the area of fuselage drag.16 pp19760003915
- Some considerations in the fatigue design of launch and spacecraft structuresMetal fatigue, structural fatigue, and strength for launch vehicle and spacecraft structures113 ppNASA-CR-242
- Some considerations on the integration of engine nacelles into low-boom aircraft conceptsA study of wind-tunnel data has shown why unexpected strong shock waves appeared in wind tunnel pressure signatures of two low-boom models, and has indicated that changes to the current methods for analyzing and designing low-boom aircraft are needed. The discussion provided corrections for the…15 pp19920076753
- Some experience using subcritical response methods in wind-tunnel flutter model studiesExperiences obtained with four methods of predicting flutter of wind-tunnel models from subcritical response data are described. The four methods are: co/quad, randomdec, power spectra density, and the peak-hold spectrum. Model excitation techniques included both forced (sinusoidal sweep) and…11 pp19770014085
- Some factors affecting the static longitudinal and directional stability characteristics of supersonic aircraft configurationsFactors affecting static, longitudinal, and directional stability characteristics of supersonic aircraft configurations43 pp19650018862
- Some Landing Gear Considerations for Space Shuttle VehiclesCriteria for designing space shuttle landing systems34 pp19710015180
- Some Landing Studies Pertinent to Glider-Reentry VehiclesResults are presented of some landing studies that may serve as guidelines in the consideration of landing problems of glider-reentry configurations. The effect of the initial conditions of sinking velocity, angle of attack, and pitch rate on impact severity and the effect of locating the rear gear…24 pp19980227749
- Some lessons learned with wind tunnelsA review is presented of some of the lessons learned from wind tunnel tests since World War II. Wind tunnels achieved a very high productivity rate during the war due in part to development testing of numerous military aircraft concepts. Following the war, in addition to development testing, a…42 pp19860014084
- Some methods for reducing wing drag and wing-Nacelle interferencePrimary efforts directed toward drag reduction centered on the design of both supercritical and subcritical families of airfoils, the reduction of induced drag through the use of vortex diffusers, and the reduction of interference drag for executive-type aircraft.20 pp19760003920
- Some Recent Information on Aircraft Vibration Due to Aerodynamic SourcesAircraft vibration due to aerodynamic forces37 pp19680025099
- SSI-ARC Flight Test 3 Data ReviewThe "Unmanned Aircraft System (UAS) Integration into the National Airspace System (NAS)" Project conducted flight test program, referred to as Flight Test 3, at Armstrong Flight Research Center from June - August 2015. Four flight test days were dedicated to the NASA Ames-developed Detect and Avoid…1 ppARC-E-DAA-TN27374
- Stability Analysis of the Slowed-Rotor Compound Helicopter ConfigurationThe stability and control of rotors at high advance ratio are considered. Teetering, articulated, gimbaled, and rigid hub types are considered for a compound helicopter (rotor and fixed wing). Stability predictions obtained using an analytical rigid flapping blade analysis, a rigid blade CAMRAD II…20 pp
- Stability and Control Analysis of the F-15B Quiet SpikeTM AircraftThe primary purpose of the Quiet Spike(TradeMark) flight research program was to analyze the aerodynamic, structural, and mechanical proof-of-concept of a large multi-stage telescoping nose spike installed on the National Aeronautics and Space Administration Dryden Flight Research Center (Edwards,…53 ppNASA/TM-2009-214651
- Stability and Control CFD Investigations of a Generic 53 Degree Swept UCAV ConfigurationNATO STO Task Group AVT-201 on "Extended Assessment of Reliable Stability & Control Prediction Methods for NATO Air Vehicles" is studying various computational approaches to predict stability and control parameters for aircraft undergoing non-linear flight conditions. This paper contributes an…27 ppNF1676L-17572
- Stability and control characteristics at low subsonic speeds of an airplane configuration having two types of variable-sweep wingsStatic stability and control at low subsonic speeds of supersonic aircraft with variable sweep wings91 ppNASA-TM-X-303
- STABILITY AND CONTROL CHARACTERISTICS OF A 0.0667-SCALE MODEL OF THE FINAL VERSION OF THE NORTH AMERICAN X-15 RESEARCH AIRPLANE CONFIGURATION 3 AT TRANSONIC SPEEDSStability & control of x-15 aircraft scale model at transonic speeds103 ppNASA-TM-X-758
- Stability and Control Derivative Characteristics of the X-15 AirplaneFlight measurements of stability and control derivative characteristics of X-15 aircraft32 ppNASA-TM-X-714
- Stability and control derivative estimates obtained from flight data for the Beech 99 aircraftLateral-directional and longitudinal stability and control derivatives were determined from flight data by using a maximum likelihood estimator for the Beech 99 airplane. Data were obtained with the aircraft in the cruise configuration and with one-third flap deflection. The estimated derivatives…38 ppNASA-TM-72863
- Stability and control derivatives of the T-37B airplaneSubsonic stability and control derivatives were determined by a modified maximum likelihood estimator from flight data for the longitudinal and lateral-directional modes of the T-37B airplane. Data from two flights, in which 166 stability and control maneuvers were performed, were used in the…33 ppNASA-TM-X-56036
- Stability and Control Estimation Flight Test Results for the SR-71 Aircraft With Externally Mounted ExperimentsA maximum-likelihood output-error parameter estimation technique is used to obtain stability and control derivatives for the NASA Dryden Flight Research Center SR-71A airplane and for configurations that include experiments externally mounted to the top of the fuselage. This research is being done…96 ppNASA/TP-2002-210718
- Stability and control of maneuvering high-performance aircraftThe stability and control of a high-performance aircraft was analyzed, and a design methodology for a departure prevention stability augmentation system (DPSAS) was developed. A general linear aircraft model was derived which includes maneuvering flight effects and trim calculation procedures for…206 ppNASA-CR-2788
- Stability and Performance Metrics for Adaptive Flight ControlThis paper addresses the problem of verifying adaptive control techniques for enabling safe flight in the presence of adverse conditions. Since the adaptive systems are non-linear by design, the existing control verification metrics are not applicable to adaptive controllers. Moreover, these…19 ppARC-E-DAA-TN803
- Stability characteristics of a tandem-rotor transport helicopter as determined by flight testManeuver stability characteristics of tandem rotor transport helicopter determined by flight test - speed and directional instabilities32 ppNASA-TN-D-2847
- Stability of the Boundary Layer and the SpotThe similarity among turbulent spots observed in various transition experiments, and the rate in which they contaminate the surrounding laminar boundary layer is only cursory. The shape of the spot depends on the Reynolds number of the surrounding boundary layer and on the pressure gradient to…28 pp20070038972
- Stability Properties and Cross Coupling Performance of the Control Allocation Scheme CAPIOThis paper presents a stability analysis and an application of a recently developed Control Allocator for recovery from Pilot Induced Oscillations (CAPIO). When actuators are rate-saturated due to either aggressive pilot commands, high gain ight control systems or some anomaly in the system, the…13 ppARC-E-DAA-TN1308
- Stability Result For Dynamic Inversion Devised to Control Large Flexible AircraftHigh performance aircraft of the future will be designed lighter, more maneuverable, and operate over an ever expanding flight envelope. One of the largest differences from the flight control perspective between current and future advanced aircraft is elasticity. Over the last decade, dynamic…14 ppAIAA Paper 2001-4284
- Stability-Augmentation Devices for Miniature AircraftNon-aerodynamic mechanical devices are under consideration as means to augment the stability of miniature autonomous and remotely controlled aircraft. Such aircraft can be used for diverse purposes, including military reconnaissance, radio communications, and safety-related monitoring of wide…1 ppLAR-16456-1
- Stabilizer flutter investigated by flight testFlight flutter tests were conducted on an experimental airplane which resulted in the successful prediction of a limited amplitude stabilizer flutter at supersonic speeds. The flutter obtained was unusual in that fore and aft bending of the stabilizer carry-through structure contributed to the…9 pp19760003017
- Starting characteristics and combustion performance of magnesium slurry in 6.5-inch-diameter ram-jet engine mounted in connected-pipe facilityThe starting characteristics and combustion performance of slurry type fuels, consisting of 50 percent magnesium powder in a hydrocarbon carrier, have been investigated in a flight-type, 6.5-inch-diameter ram-jet engine in a connected-pipe facility. Quick, dependable starting of the engine was…26 ppNACA-RM-E53K05
- State-vector control applied to lateral stability of high-performance aircraftState vector control applied to problem of lateral stability augmentation of high performance aircraft18 pp19650018213
- Static Aeroelastic Modeling of a Sub-Scale Wind Tunnel Model with Novel Flap ConceptThis paper examines the static aeroelastic modeling of a flexible wind tunnel model equipped with a novel control effector known as the Variable Camber Continuous Trailing Edge Flap (VCCTEF) system. The wind tunnel model is an approximately 10 percent sub-scale version of a wing designed to be…31 ppARC-E-DAA-TN19979
- Static Aeroelastic Scaling and Analysis of a Sub-Scale Flexible Wing Wind Tunnel ModelThis paper presents an approach to the development of a scaled wind tunnel model for static aeroelastic similarity with a full-scale wing model. The full-scale aircraft model is based on the NASA Generic Transport Model (GTM) with flexible wing structures referred to as the Elastically Shaped…41 ppARC-E-DAA-TN12576
- Static and dynamic helicopter airframe analysis with NASTRANThe use of NASTRAN at Bell Helicopter Company for structural static and dynamic analysis of a helicopter airframe is described. Analysis of airframe internal loads, main rotor isolation systems, and airframe vibration is discussed. The use of each rigid format for these types of analysis is…9 pp
- Static and dynamic pressure measurements on a NACA 0012 airfoil in the Ames High Reynolds Number FacilityThe supercritical flows at high subsonic speeds over a NACA 0012 airfoil were studied to acquire aerodynamic data suitable for evaluating numerical-flow codes. The measurements consisted primarily of static and dynamic pressures on the airfoil and test-channel walls. Shadowgraphs were also taken of…78 ppNASA-TP-2485
- Static and Dynamic Testing of Blunt Bodies in a Subsonic Magnetic Suspension Wind TunnelThe MIT 6-inch magnetic suspension wind tunnel is used in two configurations to measure lift forces of two blunt bodies and produce free-to-pitch oscillations driven by capsule static stability and dynamic instabilities. Lift tests show that static aerodynamic data can be measured on a magnetically…2 pp20190033957
- Static lateral-directional stability characteristics of five contemporary airplane models from wind-tunnel tests at high subsonic and supersonic speedsWind tunnel tests to determine lateral-directional stability of aircraft from transonic to supersonic speeds100 ppNACA-RM-A55J03
- Static longitudinal, directional, and lateral stability and control data at a Mach number of 6.83 of the final configuration of the X- 15 research airplaneX-15 aircraft static longitudinal, directional, and lateral stability and control at hypersonic speeds74 ppNASA-TM-X-236
- STATIC STABILITY AND CONTROL CHARACTERISTICS OF AN AIRPLANE MODEL WITH TAIL SURFACES OUTBOARD OF THE WING TIPS AT A MACH NUMBER OF 2.01Static stability and control characteristics of aircraft model with tail surfaces outboard of wing tips29 ppNASA-TM-X-47
- Static-thrust Investigation of Full-scale PV-2 Helicopter Rotors Having NACA 0012.6 and 23012.6 Airfoil SectionsAn investigation was conducted to compare the performance of two 25-ft-diam rotors which had identical dimensions and were similar in construction but different in blade airfoil-sections. Tests were conducted at indicated blade pitch angles from 3 degrees to 11.5 degrees and rotor speeds of 200,…24 ppNACA-MR-L6D24
- Statistical analysis of general aviation VG-VGH dataTo represent the loads spectra of general aviation aircraft operating in the Continental United States, VG and VGH data collected since 1963 in eight operational categories were processed and analyzed. Adequacy of data sample and current operational categories, and parameter distributions required…133 pp19750002861
- Statistical survey of XB-70 airplane responses and control usage with an illustration of the application to handling qualities criteriaThe magnitude and frequency of occurrence of aircraft responses and control inputs during 27 flights of the XB-70 airplane were measured. Exceedance curves are presented for the airplane responses and control usage. A technique is presented which makes use of these exceedance curves to establish or…43 pp19720019363
- Statistical Wind-Tunnel Experimentation Advancements for eVTOL Aircraft Aero-Propulsive Model DevelopmentCompared to many conventional aircraft, electric vertical takeoff and landing (eVTOL) vehicle designs present greater aero-propulsive complexity and many interacting factors requiring development of novel testing and model development strategies. This paper describes several advances in…21 pp
- Statistical Wind-Tunnel Experimentation Advancements for eVTOL Aircraft Aero-Propulsive Model Development27 pp
- Steady State Thermal Analyses of SCEPTOR X-57 Wingtip PropulsionElectric aircraft concepts enable advanced propulsion airframe integration approaches that promise increased efficiency as well as reduced emissions and noise. NASA's fully electric Maxwell X-57, developed under the SCEPTOR program, features distributed propulsion across a high aspect ratio wing.…14 pp20170007957
- Stereo Photogrammetry Measurements of the Position and Attitude of a Nozzle-Plume/Shock-Wave Interaction Model in the NASA Ames 9- by 7-Ft Supersonic Wind TunnelStereo photogrammetry was used to measure the position and attitude of a slender body of revolution during nozzle-plume/shock-wave interaction tests in the NASA Ames 9- by 7-Ft Supersonic Wind Tunnel. The model support system was designed to allow the model to be placed at many locations in the…16 pp20180002138
- Stochastic Methods for Aircraft DesignThe global stochastic optimization method, simulated annealing (SA), was adapted and applied to various problems in aircraft design. The research was aimed at overcoming the problem of finding an optimal design in a space with multiple minima and roughness ubiquitous to numerically generated…10 pp19990009940
- STOP - A computer program for supersonic transport trajectory optimizationIBM 7094 digital program using steepest ascent technique for optimizing flight path of supersonic transport aircraft335 ppNASA-CR-793
- STOVL aircraft simulation for integrated flight and propulsion control researchThe United States is in the initial stages of committing to a national program to develop a supersonic short takeoff and vertical landing (STOVL) aircraft. The goal of the propulsion community in this effort is to have the enabling propulsion technologies for this type aircraft in place to permit a…24 pp19900004073
- STOVL Control Integration ProgramAn integrated flight/propulsion control for an advanced vector thrust supersonic STOVL aircraft, was developed by Pratt & Whitney and McDonnell Douglas Aerospace East. The IFPC design was based upon the partitioning of the global requirements into flight control and propulsion control requirements.…204 ppNASA-CR-195358
- Stratified charge rotary aircraft engine technology enablement programThe multifuel stratified charge rotary engine is discussed. A single rotor, 0.7L/40 cu in displacement, research rig engine was tested. The research rig engine was designed for operation at high speeds and pressures, combustion chamber peak pressure providing margin for speed and load excursions…120 pp19850012853
- String Stability of a Linear Formation Flight Control SystemString stability analysis of an autonomous formation flight system was performed using linear and nonlinear simulations. String stability is a measure of how position errors propagate from one vehicle to another in a cascaded system. In the formation flight system considered here, each i(sup th)…17 ppNASA/TM-2002-210733
- Structural dynamic model obtained from flight use with piloted simulation and handling qualities analysisThe ability to use flight data to determine an aircraft model with structural dynamic effects suitable for piloted simulation. and handling qualities analysis has been developed. This technique was demonstrated using SR-71 flight test data. For the SR-71 aircraft, the most significant structural…30 pp19960042491
- Studies in general aviation aerodynamicsThe Department of Aerospace Engineering at the University of Maryland has completed a research study for NASA Langley on the application of drooped leading edges to high aspect wings. The experimental study conducted for this grant was a natural extension of work previously conducted at NASA Ames,…28 pp19920019268
- Studies of airframe propulsion system integration for Mach 6 cruise vehiclesAirframe-propulsion system integration for hypersonic aircraft24 pp19670029519
- Study of advanced fuel system concepts for commercial aircraftAn analytical study was performed in order to assess relative performance and economic factors involved with alternative advanced fuel systems for future commercial aircraft operating with broadened property fuels. The DC-10-30 wide-body tri-jet aircraft and the CF6-8OX engine were used as a…255 pp19850011668
- Study of aerodynamic technology for single-cruise-engine V/STOL fighter/attack aircraftA viable, single engine, supersonic V/STOL fighter/attack aircraft concept was defined. This vectored thrust, canard wing configuration utilizes an advanced technology separated flow engine with fan stream burning. The aerodynamic characteristics of this configuration were estimated and performance…181 pp19840020698
- Study of an advanced General Aviation Turbine Engine (GATE)The best technology program for a small, economically viable gas turbine engine applicable to the general aviation helicopter and aircraft market for 1985-1990 was studied. Turboshaft and turboprop engines in the 112 to 746 kW (150 to 1000 hp) range and turbofan engines up to 6672 N (1500 lbf)…147 pp19790012902
- Study of flutter related computational procedures for minimum weight structural sizing of advanced aircraftResults of a study of the development of flutter modules applicable to automated structural design of advanced aircraft configurations, such as a supersonic transport, are presented. Automated structural design is restricted to automated sizing of the elements of a given structural model. It…130 pp19760012059
- Study of fuel systems for LH2-fueled subsonic transport aircraft, volume 1Several engine concepts examined to determine a preferred design which most effectively exploits the characteristics of hydrogen fuel in aircraft tanks received major emphasis. Many candidate designs of tank structure and cryogenic insulation systems were evaluated. Designs of all major elements of…201 pp19780023142
- Study of Jet-Propulsion System Comprising Blower, Burner, and NozzleA study was made of the performance of a jet-propulsion system composed of an engine-driven blower, a combustion chamber, and a discharge nozzle. A simplified analysis is made of this system for the purpose of showing in concise form the effect of the important design variables and operating…41 ppNACA-ACR-E4E06
- Study of LH2-fueled topping cycle engine for aircraft propulsionAn analytical investigation was made of a topping cycle aircraft engine system which uses a cryogenic fuel. This system consists of a main turboshaft engine which is mechanically coupled (by cross-shafting) to a topping loop which augments the shaft power output of the system. The thermodynamic…20 pp19830026671
- Study of the integration of wind tunnel and computational methods for aerodynamic configurationsA study was conducted to determine the effectiveness of using a low-order panel code to estimate wind tunnel wall corrections. The corrections were found by two computations. The first computation included the test model and the surrounding wind tunnel walls, while in the second computation the…76 ppNASA-TM-102196
- Study of the optimum values of several parameters affecting longitudinal handling qualities of VTOL aircraftOptimum values of pitch rate damping, longitudinal control and speed stability for vertical takeoff aircraft /helicopters/ using pilot ratings14 pp19680018681
- Study on the feasibility of V/STOL concepts for short-haul transport aircraftFeasibility of V/STOL propulsion concepts for short haul transport aircraft156 pp19670005609
- Study to determine the IFR operational profile and problems to the general aviation pilotA study of the general aviation single pilot operating under instrument flight rules (GA SPIFR) has been conducted for NASA Langley Research Center. The objectives of the study were to (1) develop a GA SPIFR operational profile, (2) identify problems experienced by the GA SPIFR pilot, and (3)…23 pp
- Subcritical flutter testing and system identificationTreatment is given of system response evaluation, especially in application to subcritical flight and wind tunnel flutter testing of aircraft. An evaluation is made of various existing techniques, in conjuction with a companion survey which reports theoretical and analog experiments made to study…113 pp19740026358
- Subscale Flight Testing for Aircraft Loss of Control: Accomplishments and Future DirectionsSubscale flight-testing provides a means to validate both dynamic models and mitigation technologies in the high-risk flight conditions associated with aircraft loss of control. The Airborne Subscale Transport Aircraft Research (AirSTAR) facility was designed to be a flexible and efficient research…13 ppPaper No. 1345315
- Subscale Tiltrotor eVTOL Aircraft Dynamic Modeling and Flight Control Software DevelopmentThis paper describes the dynamic modeling and flight control software development efforts for a subscale tiltrotor electric vertical takeoff and landing (eVTOL) aircraft built at NASA Langley Research Center. The vehicle, referred to as the Research Aircraft for eVTOL Enabling techNologies (RAVEN)…22 pp
- Subsonic Aircraft Safety Icing StudyNASA's Integrated Resilient Aircraft Control (IRAC) Project is one of four projects within the agency s Aviation Safety Program (AvSafe) in the Aeronautics Research Mission Directorate (ARMD). The IRAC Project, which was redesigned in the first half of 2007, conducts research to advance the state…45 ppNASA/TM--2008-215107
- Subsonic stability and control derivatives for an unpowered, remotely piloted 3/8-scale F-15 airplane model obtained from flight testIn response to the interest in airplane configuration characteristics at high angles of attack, an unpowered remotely piloted 3/8-scale F-15 airplane model was flight tested. The subsonic stability and control characteristics of this airplane model over an angle of attack range of -20 to 53 deg are…34 ppNASA-TN-D-8136
- Subsonic Ultra Green Aircraft Research: Phase V – Buffet Test ReportThis test report summarizes work performed by the Boeing Subsonic Ultra-Green Aircraft Research (SUGAR) team in the Phase V Transonic Truss-Braced Wing contract task. The task was awarded in September 2020, and ended at the end of September 2022. As a part of the SUGAR Phase V contract task, Boeing…212 ppNASA/CR-20230005431
- Subsonic Wing Optimization for Handling Qualities Using ACSYNTThe capability to accurately and rapidly predict aircraft stability derivatives using one comprehensive analysis tool has been created. The PREDAVOR tool has the following capabilities: rapid estimation of stability derivatives using a vortex lattice method, calculation of a longitudinal handling…51 pp19960054468
- Subsonic-transonic stall flutter studyThe objective of the Subsonic/Transonic Stall Flutter Program was to obtain detailed measurements of both the steady and unsteady flow field surrounding a rotor and the mechanical state of the rotor while it was operating in both steady and flutter modes to provide a basis for future analysis and…311 pp19830022164
- Substantiation data for hypersonic cruise vehicle wing structure evaluation - Volume 1, sections 1-10Trajectory, load, aerodynamic heating, materials, structural, and thermal analyses for hypersonic cruise vehicle wings381 pp19700017938
- Suggested test of a self-calibrating baro- height reporting concept for general aviation and airline SSR Interim scientific reportSelf-calibrating baro-altitude concept for general aviation25 pp19690027089
- Summary of Airfoil DataRecent airfoil data for both flight and wind-tunnel tests have been collected and correlated insofar as possible. The flight data consist largely of drag measurements made by the wake-survey method. Most of the data on airfoil section characteristics were obtained in the Langley two-dimensional…487 ppNACA-ACR-L5005
- Summary of Airfoil DataThe historical development of NACA airfoils is briefly reviewed. New data are presented that permit the rapid calculation of the approximate pressure distributions for the older NACA four-digit and five-digit airfoils by the same methods used for the NACA 6-series airfoils. The general methods used…261 ppNACA-TR-824
- Summary of drag clean-up tests in NASA Langley full-scale tunnelThis summary of drag results presents tabulations on fighter aircraft and light twin general aviation aircraft wind tunnel tests. The figures show that the friction drag for light twins is larger than that for the fighters because of the greater wetted area and the smaller wing area used for…18 pp19760003912
- Summary of Flight-Test Results of the VZ-2 Tilt-Wing AircraftFlight-test information gained from a tilt-wing research aircraft tested at the Langley Research Center has shown that design problems exist in such fields as low-speed stability and control, handling qualities, and flow separation during transition. The control power in the near-hovering…44 pp19980227196
- Summary of NASA landing-gear researchResearch relative to tire tread, powered-wheel taxiing, air cushion landing systems, and crosswind landing gear is discussed.32 pp
- Summary of NASA landing-gear researchThis paper presents a brief summary of the airplane landing gear research underway at NASA. The technology areas include: ground handling simulator, antiskid braking systems, space shuttle nose-gear shimmy, active control landing gear, wire brush skid landing gear, air cushion landing systems,…33 ppNASA-TM-78679
- Summary of spin technology as related to light general-aviation airplanesA summary was made of all NASA (and NACA) research and experience related to the spin and recovery characteristics of light personal-owner-type general-aviation airplanes. Very little of the research deals with light general-aviation airplanes as such, but many of the airplanes and models tested…35 pp19720005341
- Summary of the effects of engine throttle response on airplane formation-flying qualitiesA flight evaluation was conducted to determine the effect of engine throttle response characteristics on precision formation-flying qualities. A variable electronic throttle control system was developed and flight-tested on a TF-104G airplane with a J79-11B engine at the NASA Dryden Flight Research…30 pp19930013934
- Summary of the general aviation manufacturers' position on aircraft piston engine emissionsThe General Aviation Manufacturers recommended that the EPA rescind the aircraft piston engine emissions regulations currently on the books. The reason was the very small emission reduction potential and the very poor benefit-cost ratio involved in this form of emission reduction. The limited…8 pp19770010155
- Summary of the Second AIAA Stability and Control Prediction WorkshopThis paper documents the setup, execution, and findings of the Second Stability and Control Prediction Workshop (S&CPW2) held at the AIAA SciTech 2025 Forum. The workshop focused on prediction of static and dynamic stability derivatives for the Common Research Model (CRM) at subsonic flight…28 pp
- Summary of the Second AIAA Stability and Control Prediction Workshop24 pp
- Summary of v-g data obtained from turbine- powered transport airplanes from 1959 to 1963Comparisons of airspeed, pressure altitude, and acceleration data between turbine and piston engine transport aircraft using NASA V-G and VGH recorders22 pp19650010881
- Supercooled Large Droplet Icing Flight Research ProgramDuring the past three winters, the NASA Glenn Research Center at Lewis Field conducted icing research flights throughout the Great Lakes region to measure the characteristics of a severe icing condition having Supercooled Large Droplets (SLD). SLD was implicated in the 1994 crash of the ATR-72…3 pp20050192376
- Supercooled Liquid Water Content Instrument Analysis and Winter 2014 Data with Comparisons to the NASA Icing Remote Sensing System and Pilot ReportsThe National Aeronautics and Space Administration (NASA) has developed a system for remotely detecting the hazardous conditions leading to aircraft icing in flight, the NASA Icing Remote Sensing System (NIRSS). Newly developed, weather balloon-borne instruments have been used to obtain in-situ…30 ppNASA/TM-2016-219092
- Supersonic Flight Dynamics Test 2: Trajectory, Atmosphere, and Aerodynamics ReconstructionThe Supersonic Flight Dynamics Test is a full-scale flight test of aerodynamic decelerator technologies developed by the Low Density Supersonic Decelerator technology demonstration project. The purpose of the project is to develop and mature aerodynamic decelerator technologies for landing…17 ppAAS Paper 16-217
- Supersonic Flight Dynamics Test: Trajectory, Atmosphere, and Aerodynamics ReconstructionThe Supersonic Flight Dynamics Test is a full-scale flight test of a Supersonic Inflatable Aerodynamic Decelerator, which is part of the Low Density Supersonic Decelerator technology development project. The purpose of the project is to develop and mature aerodynamic decelerator technologies for…17 ppAAS 15-224
- Supersonic Flying Qualities Experience Using the SR-71Approximately 25 years ago NASA Dryden Flight Research Center, Edwards, California, initiated the evaluation of supersonic handling qualities issues using the XB-70 and the YF-12. Comparison of pilot comments and ratings with some of the classical handling qualities criteria for transport aircraft…16 pp19970026105
- Supersonic Inlet Test for a Quiet Supersonic Transport Technology Demonstrator in the NASA Glenn 8- by 6-Foot Supersonic Wind TunnelNASA funded the preliminary design of a flight demonstrator aircraft with a greatly reduced sonic boom signature to enable supersonic flight over land. In 2017, two tests were performed at the NASA Glenn Research Center 8- by 6-foot Supersonic Wind Tunnel, an aerodynamic stability/control test and…24 ppNASA/TM-2018-219956
- Supersonic STOVL ejector aircraft from a propulsion point of viewA baseline supersonic STOVL ejector aircraft, its propulsion and typical operating modes is described, and important propulsion parameters are identified. Then a number of propulsion system changes are evaluated for improvement of the lift-off performance aft deflection of the ejector jet and…18 pp19840016513
- Supersonic transportAn aircraft of supersonic transport configuration is described, featuring thrust vectoring in conjunction with wing apex segments used as canard surfaces during takeoff, landing, and low-speed flight. The angle of incidence of the wing apex segments, when the segments were functioning as canard…7 pp19780024143
- Supersonic transport airport and community jet noise during takeoff and initial climbEngine design and flight characteristics effects on airport and community jet noise environment of fixed-wing supersonic commercial transport21 ppNASA-TM-X-1452
- Supersonic transport lubrication system investigation Second semiannual reportPerformance of aircraft gas turbine mainshaft ball bearings, seals, and lubricants under simulated supersonic transport engine conditions118 ppNASA-CR-54312
- Supersonic transport trajectory optimization example solutions Final reportSupersonic transport trajectory optimization example solutions280 ppNASA-CR-66247
- Supersonic Wave Drag of Sweptback Tapered Wings at Zero LiftOn the basis of a recently developed theory for sweptback wings at supersonic velocities, equations are derived for the wave drag of sweptback tapered wings with thin symmetrical double-wedge sections at zero lift. Calculations of section wave-drag distributions and wing wave drag are presented for…50 pp19930082080
- Survey of aircraft icing simulation test facilities in North AmericaA survey was made of the aircraft icing simulation facilities in North America: there are 12 wind tunnels, 28 engine test facilities, 6 aircraft tankers and 14 low velocity facilities, that perform aircraft icing tests full or part time. The location and size of the facility, its speed and…30 ppNASA-TM-81707
- Survey of aircraft subcritical flight flutter testing methodsThe results of a survey of U. S., British and French subcritical aircraft flight flutter testing methods are presented and evaluation of the applicability of these methods to the testing of the space shuttle are discussed. Ten U. S. aircraft programs covering the large civil transport aircraft and…30 pp19740026355
- Switching LPV Control of an F-16 Aircraft via Controller State ResetIn flight control, the design objective and the aircraft dynamics may be different in low and high angle of attack regions. This paper presents a systematic switching Linear Parameter-varying LPV method to determine if it is practical to use for flight control designs over a wide angle of attack…24 pp
- Symbology Development for General Aviation Synthetic Vision Primary Flight Displays for the Approach and Missed-Approach Modes of FlightSpatial disorientation induced by inadvertent flight into instrument meteorological conditions (IMC) continues to be a leading cause of fatal accidents in general aviation. The Synthetic Vision Systems General Aviation (SVS-GA) research element, an integral part of NASA s Aviation Safety and…5 pp20040139478
- Synthesis of aircraft noiseSimulation procedure for aircraft noise spectra during takeoff and flight9 pp
- System Identification for a Subscale Tiltrotor eVTOL Aircraft from Hover Flight-Test DataThis paper describes the system identification process and hover flight-test modeling results for a subscale tiltrotor electric vertical takeoff and landing (eVTOL) vehicle built at NASA Langley Research Center. The vehicle, referred to as the Research Aircraft for eVTOL Enabling techNologies…25 pp
- Systems Analysis Developed for All-Electric Aircraft PropulsionThere is a growing interest in the use of fuel cells as a power source for all-electric aircraft propulsion as a means to substantially reduce or eliminate environmentally harmful emissions. Among the technologies under consideration for these concepts are advanced proton exchange membrane (PEM)…2 pp20050192206
- Systems Analysis Initiated for All-Electric Aircraft PropulsionA multidisciplinary effort is underway at the NASA Glenn Research Center to develop concepts for revolutionary, nontraditional fuel cell power and propulsion systems for aircraft applications. There is a growing interest in the use of fuel cells as a power source for electric propulsion as well as…2 pp20050214685
- Systems analysis of the installation, mounting, and activation of emergency locator transmitters in general aviation aircraftA development program was developed to design and improve the Emergency Locator Transmitter (ELT) transmitter and to improve the installation in the aircraft and its activation subsystem. There were 1135 general aviation fixed wing aircraft accident files reviewed. A detailed description of the…207 pp19810001512
- Tables of Interference Factors for Use in Wind-tunnel and Ground-effect Calculations for VTOL-STOL Aircraft. Part I - Wind Tunnels Having Width-height Ratio of 2.0Tables of interference factors for use in wind-tunnel and ground-effect calculations for VTOL-STOL aircraft are presented for wind tunnels having a width-height ratio of 2.0. These tables were machine-calculated and are intended for use with the procedures of NASA Technical Report R-124. These…210 ppNASA-TN-D-933
- Tables of Interference Factors for Use in Wind-tunnel and Ground-effect Calculations for VTOL-STOL Aircraft. Part II - Wind Tunnels Having Width-height Ratio of 1.5Interference factor tables for wind-tunnel and ground-effect calculations for vtol-stol aircraft part ii - width-height ratio 1.5204 ppNASA-TN-D-934
- Tailless aircraft performance improvements with relaxed static stabilityThe purpose is to determine the tailless aircraft performance improvements gained from relaxed static stability, to quantify this potential in terms of range-payload improvements, and to identify other possible operational and handling benefits or problems. Two configurations were chosen for the…140 ppNASA-CR-181806
- Tankage systems for a methane fueled supersonic transportFuel systems and storage tanks for methane fueled supersonic transport15 pp19680003358
- Tankage systems for a methane-fueled supersonic transportTankage systems for methane-fueled supersonic transport22 pp19680014426
- Technical Challenges and Barriers Affecting Turbo-Electric and Hybrid Electric Aircraft PropulsionIn order to meet aggressive aircraft performance goals set by NASA's Aeronautics Research Mission Directorate, the Glenn Research Center (GRC) is leading research and development of electrified aircraft propulsion systems with electricity being generated from a gas turbine engine or combination of…30 pp20180004252
- Techniques to improve maneuver stability characteristics of a nonlinear wide-body transport airplane in cruise flightThe maneuver control stability characteristics of an aircraft are a flying qualities parameter of critical importance, to ensure structural protection as well as adequate predictability to the pilot. Currently, however, maneuver stability characteristics are not uniquely addressed in the Federal…66 ppNASA-TM-4521
- Technologies for Aircraft Noise ReductionTechnologies for aircraft noise reduction have been developed by NASA over the past 15 years through the Advanced Subsonic Technology (AST) Noise Reduction Program and the Quiet Aircraft Technology (QAT) project. This presentation summarizes highlights from these programs and anticipated noise…24 pp
- Technology assessment of advanced general aviation aircraftInfluence of advanced technology and design philosophies on general aviation aircraft for 198558 pp19710025741
- Technology Assessment of Advanced General Aviation AircraftPotential impact of advanced technology in 1985 on four types of general aviation aircraft including STOL V/STOL, and helicopters377 pp19710025734
- Technology for reducing aircraft engine pollutionPrograms have been initiated by NASA to develop and demonstrate advanced technology for reducing aircraft gas turbine and piston engine pollutant emissions. These programs encompass engines currently in use for a wide variety of aircraft from widebody-jets to general aviation. Emission goals for…38 pp19750010165
- Testing and analysis of dual-mode adaptive landing gear, taxi mode test system for YF-12AThe effectiveness of a dual mode adaptive landing gear system in reducing the dynamic response of an airplane during ground taxiing was studied. The dynamic taxi tests of the YF-12A research airplane are presented. A digital computer program which simulated the test conditions is discussed. The…53 pp19790023021
- Tests If a Highly Cambered Low-Drag-Airfoil Section with a Lift-Control Flap, Special ReportTests were made in the NACA two-dimensional low turbulence pressure tunnel of a highly cambered low-drag airfoil (NACA 65,3-618) with a plain flap designed for lift control. The results indicate that such a combination offers attractive possibilities for obtaining low profile-drag coefficients over…11 ppNACA-ACR-242
- Tests in the variable-density wind tunnel of the NACA 23012 airfoil with plain and split flapsSection characteristics for use in wing design are presented for the NACA 23012 airfoil with plain and split flaps of 20 percent wing chord at a value of the effective Reynolds number of about 8,000,000. The flap deflections covered a range from 60 degrees upward to 75 degrees downward for the…9 ppNACA-TR-661
- Tests of a NACA 65(sub 1)-213 airfoil in the NASA Langley 0.3-meter transonic cryogenic tunnelA wind-tunnel investigation was conducted to study the two dimensional aerodynamic characteristics of the NACA 65 sub 1-213 airfoil over a wide range of Reynolds numbers. Test temperature ranged from ambient to about 100K at pressures ranging from about 1.2 to 6.0 atm. Mach number was varied from…102 ppNASA-TM-85732
- Tests of an NACA 66,2-420 Airfoil of 5-Foot Chord at High Speed, Special ReportThis report covers tests of a 5-foot model of the NACA 66,2-420 low-drag airfoil at high speeds including the critical compressibility speed. Section coefficients of lift, drag, and pitching moment, and extensive pressure-distribution data are presented. The section drag coefficient at the design…22 ppNACA-SR-234
- Tests of the NACA 653-018 airfoil section with boundary-layer control by suction27 ppNACA-WR-L-209
- The Acoustic Environment of the NASA Glenn 9- by 15-foot Low-Speed Wind TunnelThe 9- by 15-Foot Low Speed Wind Tunnel is an acoustic testing facility with a long history of aircraft propulsion noise research. Due to interest in renovating the facility to support future testing of advanced quiet engine designs, a study was conducted to document the background noise level in…11 ppGRC-E-DAA-TN23684
- The acoustics of a small-scale helicopter rotor in hoverA 2.1 m diameter, 1/6-scale model helicopter main rotor was tested in hover in the test section of the NASA Ames 40- by 80-foot wind tunnel. Performance and noise data on a small-scale rotor at various thrust coefficients and tip Mach numbers were obtained for comparison with existing data on…96 ppNASA-TM-101058
- The active flexible wing aeroservoelastic wind-tunnel test programFor a specific application of aeroservoelastic technology, Rockwell International Corporation developed a concept known as the Active Flexible Wing (AFW). The concept incorporates multiple active leading-and trailing-edge control surfaces with a very flexible wing such that wing shape is varied in…39 pp
- The Advanced Ducted Propulsor in the Upgraded 9- by 15-Foot Low Speed Wind TunnelA low pressure ratio, variable pitch scale model of an aircraft engine fan was tested in the NASA Glenn Research Center 9-by 15-Foot Low Speed Wind Tunnel. The Advanced Ducted Propulsor designed by Pratt & Whitney in the 1990’s and has been part of multiple wind tunnel test campaigns over the…14 pp
- The aerodynamic design of the oblique flying wing supersonic transportThe aerodynamic design of a supersonic oblique flying wing is strongly influenced by the requirement that passengers must be accommodated inside the wing. It was revealed that thick oblique wings of very high sweep angle can be efficient at supersonic speeds when transonic normal Mach numbers are…72 pp19900019224
- The Aerodynamic Effect of a Retractable Landing GearTests were conducted in the N.A.C.A. full scale wind tunnel at the request of the Army Air Corps to determine the effect of retractable landing gear openings in the bottom surface of a wing upon the characteristics of a Lockheed Altair airplane. The tests were extended to include the determination…7 ppNACA-TN-456
- The Altitude Wind Tunnel (AWT): A unique facility for propulsion system and adverse weather testingA need has arisen for a new wind tunnel facility with unique capabilities for testing propulsion systems and for conducting research in adverse weather conditions. New propulsion system concepts, new aircraft configurations with an unprecedented degree of propulsion system/aircraft integration, and…22 ppNASA-TM-86921
- The application of measurement techniques to track flutter testingThe application is discussed of measurement techniques to captive flight flutter tests at the Supersonic Naval Ordnance Research Track (SNORT), U. S. Naval Ordnance Test Station, China Lake, California. The high-speed track, by its ability to prove the validity of design and to accurately determine…9 pp19760003014
- The Balsa bullet: A high speed, low-cost general aviation aircraft for AeroworldThe Balsa Bullet is a high speed, low cost six passenger general aviation aircraft. It will cruise at a speed of 55 ft/s with a maximum speed of 75 ft/s for distances in excess of 27000 feet. This range and speed combination provide The Balsa Bullet with the capability to service any two existing…172 pp19950006225
- The C-5A active lift distribution control systemThe ALDCS development and design tasks, ALDCS functional configuration, and resulting challenges encountered while accomplishing the first phase of the program are described. These tasks are establishing system requirements and criteria and synthesizing a system mechanization to meet the desired…27 pp
- The characteristics of 78 related airfoil sections from tests in the variable-density wind tunnelAn investigation of a large group of related airfoils was made in the NACA variable-density wind tunnel at a large value of the Reynolds number. The tests were made to provide data that may be directly employed for a rational choice of the most suitable airfoil section for a given application. The…61 ppNACA-TR-460
- The characteristics of the NACA M-12 airfoil sectionThe data obtained on the NACA M-12 airfoil, tested at twenty atmosphere density in the NACA variable density wind tunnel, have been extended by additional tests at one and at twenty atmospheres under improved conditions. The results of these tests are given. Considerable scale effect was found.8 ppNACA-TN-243
- The Combination of Internal-Combustion Engine and Gas TurbineWhile the gas turbine by itself has been applied in particular cases for power generation and is in a state of promising development in this field, it has already met with considerable success in two cases when used as an exhaust turbine in connection with a centrifugal compressor, namely, in the…47 pp20050019425
- The design of a long-range megatransport aircraftAircraft manufacturers are examining the market and feasibility of long-range passenger aircraft carrying more than 600 passengers. These aircraft would carry travelers at reduced cost and, at the same time, reduce congestion around major airports. The design of a large, long-range transport…10 pp19940021225
- The design of four hypersonic reconnaissance aircraftFour different hypersonic reconnaissance aircraft were designed by separate student teams. These aircraft were designed to provide the U.S. with a system to acquire aerial tactical reconnaissance when satellite reconnaissance proved unobtainable or ineffective. The design requirements given for…10 pp19940021223
- The Development of an Airborne Information Management System for Flight TestAn airborne information management system is being developed at the NASA Dryden Flight Research Facility. This system will improve the state of the art in management data acquisition on-board research aircraft. The design centers around highly distributable, high-speed microprocessors that allow…10 ppAIAA-92-4113
- The development of cambered airfoil sections having favorable lift characteristics at supercritical Mach numbersSeveral groups of new airfoil sections, designated as the NACA 8-series, are derived analytically to have lift characteristics at supercritical Mach numbers which are favorable in the sense that the abrupt loss of lift, characteristic of the usual airfoil section at Mach numbers above the critical,…27 ppNACA-TR-947
- The Development of Cambered Airfoil Sections Having Favorable Lift Characteristics at Supercritical Mach NumbersSeveral groups of new airfoil sections, designated as the NACA 8-series, are derived analytically to have lift characteristics at supercritical Mach numbers which are favorable in the sense that the abrupt loss of lift, characteristic of the usual airfoil section at Mach numbers above the critical,…82 ppNACA-TN-1771
- The Drag of Airplane Wheels, Wheel Fairings, and Landing Gears: ITests were made in the 7- by 10-foot wind tunnel and in the 20-foot tunnel of the National Advisory Committee for Aeronautics to determine the drag of a number of airplane wheels, what fairings, and landing gears designed or selected for an airplane of 3,000 pounds gross weight. all tests were made…35 pp19930091559
- The Drag of Airplane Wheels, Wheel Fairings, and Landing Gears: IIIThe tests reported in this paper conclude the investigation of landing-gear drag that has been carried out in the N. A. C. A. 20-foot wind tunnel. They supplement earlier tests (reported in Technical Report No. 485) made with full-scale dummy wheels, wheel fairings, and landing gears intended for…16 pp19930091595
- The economic impact of drag in general aviationGeneral aviation aircraft fuel consumption and operating costs are closely linked to drag reduction methods. Improvements in airplane drag are envisioned for new models; their effects will be in the 5 to 10% range. Major improvements in fuel consumption over existing turbofan airplanes will be the…10 pp19760003919
- The Edge supersonic transportAs intercontinental business and tourism volumes continue their rapid expansion, the need to reduce travel times becomes increasingly acute. The Edge Supersonic Transport Aircraft is designed to meet this demand by the year 2015. With a maximum range of 5750 nm, a payload of 294 passengers and a…126 pp19930008866
- The effect of engine component noise on V/STOL aircraft noise contoursAn analytical study of fly-over noise using noise contours to show the effects of varying airplane and path parameters. The method of approach was to synthesize engine component noise spectra and exercise these components along given flight paths to measure the individual and total fly-over effect…115 pp19740012554
- The effect of heavy rain on an airfoil at high liftNo serious studies of the relationship of heavy rain to aircraft safety were made until 1981 when it was suggested that the torrential rain which often occurs at the time of severe wind shear might substantially increase the danger to aircraft operating at slow speeds and high lift in the vicinity…36 pp19870010799
- The Effect of Incoming Boundary Layer Characteristics on the Performance of a Distributed Propulsion SystemAn experimental study is conducted in an effort to advance the understanding of flow physics associated with a boundary layer ingesting, distributed propulsion system. The influence of incoming boundary layer thickness and flow distortions are studied on the flow downstream and the overall…24 pp20190004930
- The Effect of Systematic Error in Forced Oscillation TestingOne of the fundamental problems in flight dynamics is the formulation of aerodynamic forces and moments acting on an aircraft in arbitrary motion. Classically, conventional stability derivatives are used for the representation of aerodynamic loads in the aircraft equations of motion. However, for…19 pp20120001457
- The effectiveness at high speeds of a 10-percent-chord plain trailing-edge flap on the NACA 65-210 airfoil sectionThis report contains the results of a high-speed wind-tunnel investigation of the effectiveness of a 10-percent-chord plain flap on the NACA 65-210 airfoil section. The results include an indication of the lift-producing characteristics and the effectiveness of the 10-percent-chord flap. From a…28 ppNACA-RM-A8A21
- The Effectiveness at High Speeds of a 20-Percent-Chord Plain Trailing-Edge Flap on the NACA 65-210 AirfoilAn analysis has been made of the lift control effectiveness of a 20-percent-chord plain trailing-edge flap on the NACA 65-210 airfoil section from section lift-coefficient data obtained at Mach numbers from 0.3 to 0.875. In addition, the effectiveness of the plain flap as a lift-control device has…21 ppNACA-RM-A7A17
- The Effectiveness at High Speeds of a 20-Percent-chord Plain Trailing-edge Flap on the NACA 65-210 Airfoil SectionAn analysis has been made of the lift-control effectiveness of a 20-percent-chord plain trailing-edge flap on the NACA 65-210 airfoil section from section lift-coefficient data obtained at Mach numbers from 0.3 to 0.875. In addition, the effectiveness of the plain flap as a lift-control device has…21 ppNACA-RM-SA7A17
- The effects of aircraft design on STOL ride qualityEffects of aircraft dynamic characteristics on passenger ride quality are investigated to determine ride-quality isocontours similar to aircraft handling-qualities contours. Measurements are made on a moving-base simulator while varying the aircraft short-period and Dutch Roll frequencies and…101 pp19750018929
- The Effects of Ambient Conditions on Helicopter Rotor Source Noise ModelingA new physics-based method called Fundamental Rotorcraft Acoustic Modeling from Experiments (FRAME) is used to demonstrate the change in rotor harmonic noise of a helicopter operating at different ambient conditions. FRAME is based upon a non-dimensional representation of the governing acoustic and…19 ppNF1676L-11480
- The Effects of Blowing Over Various Trailing-edge Flaps on an NACA 0006 Airfoil Section, Comparisons with Various Types of Flaps on other Airfoil Sections, and an Analysis of Flow and Power Relationships for Blowing SystemsThe results are presented of a two-dimensional investigation conducted to determine the effect of blowing over various types of trailing-edge flaps on a wing having the NACA 0006 airfoil section and a drooped-nose flap. The position and profile of the trailing-edge flap, the nozzle height, and the…148 ppNASA-TN-D-8293
- The effects of lateral aerodynamic uncertainties on the handling qualities of the space shuttle orbiter at Mach numbers of 1.5 and .6The effects of aerodynamic uncertainties on the handling qualities of the space shuttle orbiter were investigated with the use of six-degree-of-freedom, nonlinear equations of motion on the hybrid computer system. Flight condition characteristics for Mach numbers of 1.5 and .6 for the nominal and…40 pp19820003178
- The Effects of Reynolds Number on the Application of NACA 16 Series Airfoil Characteristics to Propeller DesignAn analysis has been made of airfoil data taken on several NACA 16-series propeller airfoils from tests of 5-inch-chord models in the Langley 24 inch high-speed tunnel and l2-inch-chord models in the Langley 8 foot high-speed tunnel, This analysis has shown that the combined effects of Reynolds…16 ppNACA-RM- L7H12
- The effects of variations in Reynolds number between 3.0 x 10sub6 and 25.0 x 10sub6 upon the aerodynamic characteristics of a number of NACA 6-series airfoil sectionsResults are presented of an investigation made to determine the two-dimensional lift and drag characteristics of nine NACA 6-series airfoil section at Reynolds numbers of 15.0 x 10sub6, 20.0 x 10sub6, and 25.0 x 10sub6. Also presented are data from NACA Technical Report 824 for the same airfoils at…20 ppNACA-TR-964
- The Elite: A high speed, low-cost general aviation aircraft for AeroworldThe Elite is a six passenger, general aviation aircraft targeted at the upper middle class private pilot. The Elite is a low wing, conventional monoplane utilizing rudder, ailerons, and a stabilator. The Elite will create a new class of aircraft in Aeroworld. This class of aircraft will demonstrate…144 pp19950006117
- The estimation of airplane performance from wind tunnel tests on conventional airplane modelsCalculations of the magnitude of the correction factors and the range of their variations for wind tunnel models used in making aircraft performance predictions were made for 23 wind tunnel models. Calculated performances were compared with those actually determined for such airplanes as have been…19 ppNACA-TN-218
- The Evolution of the Viking Landing GearThe primary function of the landing gear is to dissipate touchdown energy in a controlled fashion that minimizes the landing shock for onboard components while maximizing ground clearance and the probability of landing stability over the range of possible surface and touchdown parameter variations.…11 pp
- The F-12 series aircraft approach to design for control system reliabilityThe F-12 series aircraft control system design philosophy is reviewed as it pertains to functional reliability. The basic control system, i.e., cables, mixer, feel system, trim devices, and hydraulic systems are described and discussed. In addition, the implementation of the redundant stability…12 pp
- The F-15B Lifting Insulating Foam Trajectory (LIFT) Flight TestA series of flight tests has been performed to assess the structural survivability of space shuttle external tank debris, known as divots, in a real flight environment. The NASA F-15B research test bed aircraft carried the Aerodynamic Flight Test Fixture configured with a shuttle foam divot…58 pp20060022548
- The fatigue behavior of materials for the supersonic transportCrack propagation behavior, residual static strength, and base fatigue strength of supersonic transport skin material96 ppNASA-CR-215
- The gate studies: Assessing the potential of future small general aviation turbine enginesFour studies were completed that explore the opportunities for future General Aviation turbine engines (GATE) in the 150-1000 SHP class. These studies forecasted the potential impact of advanced technology turbine engines in the post-1988 market, identified important aircraft and missions,…24 pp19790007787
- The General Aviation Propulsion (GAP) ProgramThe General Aviation Propulsion (GAP) Program Turbine Engine Element focused on the development of an advanced small turbofan engine. Goals were good fuel consumption and thrust-to-weight ratio, and very low production cost. The resulting FJX-2 turbofan engine showed the potential to meet all of…65 pp20080031112
- The handling qualities and flight characteristics of the Grumman design 698 simulated twin-engine tilt Nacelle V/STOL aircraftThis paper describes three government-conducted, piloted flight simulations of the Grumman Design 698 vertical and short takeoff and landing (V/STOL) aircraft. Emphasis is placed on the aircraft's handling qualities as rated by various NASA, Navy, and Grumman Aerospace Corporating pilots with…111 pp19870003125
- The High Stability Engine Control (HISTEC) Program: Flight Demonstration PhaseFuture aircraft turbine engines, both commercial and military, must be able to accommodate expected increased levels of steady-state and dynamic engine-face distortion. The current approach of incorporating sufficient design stall margin to tolerate these increased levels of distortion would…16 ppNASA/TM-1998-208482
- The icing problem - Current status of NACA techniques and researchThis paper summarizes some of the techniques used in N.A.C.A. research programs, in flight and in tunnels, to solve aircraft icing problems and it indicates the scope of the data avail-able for the design of aircraft icing protection systems. Sufficient data have been obtained, generalized where…45 pp
- The impact of circulation control on rotary aircraft controls systemsApplication of circulation to rotary wing systems is a new development. Efforts to determine the near and far field flow patterns and to analytically predict those flow patterns have been underway for some years. Rotary wing applications present a new set of challenges in circulation control…10 pp
- The Impact of Truth Surrogate Variance on Quality Assessment/Assurance in Wind Tunnel TestingMinimum data volume requirements for wind tunnel testing are reviewed and shown to depend on error tolerance, response model complexity, random error variance in the measurement environment, and maximum acceptable levels of inference error risk. Distinctions are made between such related concepts…29 pp20160010165
- The Implications of Handling Qualities in Civil Helicopter Accidents Involving Hover and Low Speed FlightBecause of increasing accident rates in Army helicopters in hover and low speed flight, a study was made in 1999 of accidents which could be attributed to inadequate stability augmentation. A study of civil helicopter accidents from 1993-2004 was then undertaken to pursue the issue of poor handling…16 pp20060051639
- The influence of ice accretion physics on the forecasting of aircraft icing conditionsThe physics which control aircraft ice accretion are reviewed in the context of identifying and forecasting hazardous icing conditions. The severity of aircraft icing is found to be extremely sensitive to temperature, liquid water content and droplet size distribution particularly near the…5 pp
- The influence of response feedback loops on the lateral-directional dynamics of a variable-stability transport aircraftResponse feedback control loops effects on lateral-directional dynamics of variable stability transport aircraft47 pp19670017216
- The influence of sweep on the aerodynamic loading of an oscillating NACA 0012 airfoil. Volume 1: Technical reportAerodynamic experiments were performed on an oscillating NACA 0012 airfoil utilizing a tunnel-spanning wing in both unswept and 30 degree swept configurations. The airfoil was tested in steady state and in oscillatory pitch about the quarter chord. The unsteady aerodynamic loading was measured…137 ppNASA-CR-3092
- The investigation of a variable camber blade lift control for helicopter rotor systemsA new rotor configuration called the variable camber rotor was investigated numerically for its potential to reduce helicopter control loads and improve hover performance. This rotor differs from a conventional rotor in that it incorporates a deflectable 50% chord trailing edge flap to control…131 ppNASA-CR-3503
- The ionizing radiations in supersonic transport flightsIonizing radiation in supersonic transport flights21 ppNASA-TM-X-56122
- The measurement of aircraft performance and stability and control after flight through natural icing conditionsThe effects of airframe icing on the performance and stability and control of a twin-engine commuter-class aircraft were measured by the NASA Lewis Research Center. This work consisted of clear air tests with artificial ice shapes attached to the horizontal tail, and natural icing flight tests in…48 ppNASA-TM-87265
- The mechanical design of a two-stage impulse turbine for the liquid hydrogen turbopump of the M-1 engineMechanical design of two-stage impulse turbine for liquid hydrogen turbopump of M-1 engine70 ppNASA-CR-54821
- The Multirotor Test Bed – A New NASA Test Capability for Advanced VTOL Rotorcraft ConfigurationsIn November 2019, NASA completed the first wind tunnel test entry of the Multirotor Test Bed (MTB), a new test capability for advanced VTOL rotorcraft configurations. The MTB had been under development since 2017 when the need arose for an easily reconfigurable test stand for multirotor aircraft…12 pp
- The NACA CYH Airfoil SectionThe NACA CYH airfoil section is described and its aerodynamic characteristics are given as tested in the NACA variable density wind tunnel at twenty atmosphere pressure. This section has a low drag, a high maximum lift, and a small travel of center of pressure.9 ppNACA-TN-240
- The NACA variable-density wind tunnelThis report describes the redesigned variable-density wind tunnel of the National Advisory Committee for Aeronautics; it supersedes a previous report that described the original tunnel. The operation of the balance and the method of testing are explained and the method of correcting and presenting…10 ppNACA-TR-416
- The NASA aircraft icing research programThe objective of the NASA aircraft icing research program is to develop and make available to industry icing technology to support the needs and requirements for all weather aircraft designs. Research is being done for both fixed and rotary wing applications. The NASA program emphasizes technology…27 pp
- The NASA aircraft icing research programThe objective of the NASA aircraft icing research program is to develop and make available to industry icing technology to support the needs and requirements for all-weather aircraft designs. Research is being done for both fixed wing and rotary wing applications. The NASA program emphasizes…28 pp
- The NASA Altitude Wind Tunnel (AWT): Its role in advanced icing research and developmentCurrently experimental aircraft icing research is severely hampered by limitations of ground icing simulation facilities. Existing icing facilities do not have the size, speed, altitude, and icing environment simulation capabilities to allow accurate studies to be made of icing problems occurring…20 pp19850007449
- The NASA Aviation Safety Program: OverviewIn 1997, the United States set a national goal to reduce the fatal accident rate for aviation by 80% within ten years based on the recommendations by the Presidential Commission on Aviation Safety and Security. Achieving this goal will require the combined efforts of government, industry, and…14 ppNASA/TM-2000-209810
- The NASA Environmentally Responsible Aviation Project/General Electric Open Rotor Test CampaignThe Open Rotor is a modern version of the UnDucted Fan (UDF) that was flight tested in the late 1980ʼs through a partnership between NASA and General Electric (GE). Tests were conducted in the 9ʼx15ʼ Low Speed Wind Tunnel and the 8ʼx6ʼ Supersonic Wind Tunnel starting in late 2009 and completed in…19 pp20150009575
- The NASA landing gear test airplaneA tire and landing gear test facility has been developed and incorporated into a Convair 990 aircraft. The system can simulate tire vertical load profiles to 250,000 lb, sideslip angles to 15 degrees, and wheel braking on actual runways. Onboard computers control the preprogrammed test profiles…26 ppNASA-TM-4703
- The NASA research program on propulsion for supersonic cruise aircraftThe objectives and status of the propulsion portion of a program aimed at advancing the technology and establishing a data base appropriate for the possible future development of supersonic cruise aircraft are reviewed. Research related to exhaust nozzles, combustors, and inlets that is covered by…24 pp19750010166
- The natural flow wing-design conceptA wing-design study was conducted on a 65 degree swept leading-edge delta wing in which the wing geometry was modified to take advantage of the naturally occurring flow that forms over a slender wing in a supersonic flow field. Three-dimensional nonlinear analysis methods were used in the study…49 pp19920015959
- The New Heavy Gas Testing Capability in the NASA Langley Transonic Dynamics TunnelThe NASA Langley Transonic Dynamics Tunnel (TDT) has provided a unique capability for aeroelastic testing for over thirty-five years. The facility has a rich history of significant contributions to the design of many United States commercial transports and military aircraft. The facility has many…14 pp19970015319
- The Real-Time Wall Interference Correction System of the NASA Ames 12-Foot Pressure Wind TunnelAn improved version of the Wall Signature Method was developed to compute wall interference effects in three-dimensional subsonic wind tunnel testing of aircraft models in real-time. The method may be applied to a full-span or a semispan model. A simplified singularity representation of the…206 pp19980223963
- The requirements for a new full scale subsonic wind tunnelJustification and requirements are presented for a large subsonic wind tunnel capable of testing full scale aircraft, rotor systems, and advanced V/STOL propulsion systems. The design considerations and constraints for such a facility are reviewed, and the trades between facility test capability…31 ppNASA-TM-X-62106
- The results of a wind tunnel investigation of a model rotor with a free tipThe results of a wind-tunnel test of the free tip rotor are presented. The free tip extended over the outer 10% of the rotor blade and included a simple, passive controller mechanism. Wind-tunnel test hardware is described. The free-tip assembly, which includes the controller, functioned flawlessly…178 ppNASA-TM-86758
- The Rotary Combustion Engine: a Candidate for General AviationThe state of development of the rotary combustion engine is discussed. The nonturbine engine research programs for general aviation and future requirements for general aviation powerplants are emphasized.187 pp19790007790
- The shock-absorbed system of the airplane landing gearA discussion is given of the behavior of the shock-absorbing system, consisting of elastic struts and tires, under landing, take-off, and taxying conditions, and a general formula derived for obtaining the minimum stroke required to satisfy the conditions imposed on the landing gear. Finally, the…23 ppNACA-TM-938
- The Typical General Aviation AircraftThe reliability of General Aviation aircraft is unknown. In order to "assist the development of future GA reliability and safety requirements", a reliability study needs to be performed. Before any studies on General Aviation aircraft reliability begins, a definition of a typical aircraft that…32 ppNASA/CR-1999-209550
- The Ultra Light Aircraft TestingThe final report for grant NAG1-345 is presented. Recently, the bulk of the work that the grant has supported has been in the areas of ride quality and the structural analysis and testing of ultralight aircraft. The ride quality work ended in May 1989. Hence, the papers presented in this final…168 pp19930020585
- The use of pilot rating in the evaluation of aircraft handling qualitiesPilot rating scales and their use in assessing aircraft handling qualities60 pp19690013177
- The variation with Reynolds number of pressure distribution over an airfoil sectionPressures were simultaneously measured at 54 orifices distributed over the midspan section of a 5 by 30-inch rectangular model of the NACA 4412 airfoil in the variable-density tunnel. These measurements were made at 17 angles of attack from -20 degrees to 30 degrees for eight values of the…20 ppNACA-TR-613
- The x-15 flight test instrumentationFlight test instrumentation for x-15 aircraft34 ppNASA-TM-X-56000
- The Zero-Lift Drag of Several Configurations of the XAAM-N-2 Pilotless Aircraft. TED No. NACA DE332Free-flight tests have been made to determine the zero-lift drag of several configurations of the XAAM-N-2 pilotless aircraft. Base-pressure measurements were also obtained for some of the configurations. The results show that increasing the wing-thickness ratio from 4 to 6 percent increased the…20 pp20090026496
- Theoretical and experimental data for a number of NACA 6A-series airfoil sectionsThe NACA 6a-series airfoil sections were designed to eliminate the trailing-edge cusp which is characteristic of the NACA 6a-series sections. Theoretical data are presented for NACA 6a-series basic thickness forms having the position of minimum pressure of 30, 40, and 50 percent chord and with…25 ppNACA-TR-903
- Theoretical and Experimental Data for a Number of NACA 6A-Series Airfoil SectionsThe NACA 6A-series airfoil sections were designed to eliminate the trailing-edge cusp which is characteristic of the NACA 6-series sections. Theoretical data are presented for NACA 6A-series basic thickness forms having the position of minimum pressure at 30-, 40-, and 50-percent chord and with…44 ppNACA-RM-L6J01
- Theoretical and experimental investigation of boundary layer control in low-density nozzles by wall suction and coolingReduction of boundary layer thickness in low density nozzles by wall suction and cooling64 pp19640010814
- Theoretical dynamic analysis of the landing loads on a vehicle with a tricycle landing gearTheoretical dynamic analysis of landing loads on vehicle with tricycle landing gear compared with X-15 aircraft data34 ppNASA-TN-D-4075
- THEORETICAL INVESTIGATION OF THE SLIDEOUT DYNAMICS OF A VEHICLE EQUIPPED WITH A TRICYCLE SKID-TYPE LANDING-GEAR SYSTEMTricycle skid-type landing gear system - equations of motion for x-15 vehicle slideout dynamics32 ppNASA-TN-D-1828
- Theoretical Stability Derivatives for the X-15 Research Airplane at Supersonic and Hypersonic Speeds Including a Comparison with Wind-tunnel ResultsLongitudinal and lateral stability and control derivatives for X-15A aircraft at supersonic and hypersonic speeds - comparison of theoretical results with wind tunnel testing116 ppNASA-TM-X-287
- Three Dimensional Aerodynamic Analysis of a High-Lift Transport ConfigurationTwo computational methods, a surface panel method and an Euler method employing unstructured grid methodology, were used to analyze a subsonic transport aircraft in cruise and high-lift conditions. The computational results were compared with two separate sets of flight data obtained for the cruise…13 pp20040121213
- Three-Dimensional Modeling of Aircraft High-Lift Components with Vehicle Sketch PadVehicle Sketch Pad (OpenVSP) is a parametric geometry modeler that has been used extensively for conceptual design studies of aircraft, including studies using higher-order analysis. OpenVSP can model flap and slat surfaces using simple shearing of the airfoil coordinates, which is an appropriate…14 pp20170006246
- Thrust vectoring for lateral-directional stabilityThe advantages and disadvantages of using thrust vectoring for lateral-directional control and the effects of reducing the tail size of a single-engine aircraft were investigated. The aerodynamic characteristics of the F-16 aircraft were generated by using the Aerodynamic Preliminary Analysis…76 ppNASA-CR-186016
- Tiltrotor Test Rig Wind-Tunnel Test Data CatalogThe Tiltrotor Test Rig (TTR) is a large-scale proprotor test system for the National Full-Scale Aerodynamics Complex (NFAC). The first wind-tunnel entry was completed in November 2018 with a modern, 26-ft diameter proprotor. The rotor tested was the Bell Model 699, an AW609 rotor modified…144 ppNASA/TM-20240008170
- Time-varying Weights in Multi-Objective Optimal Control for Flexible Wing AircraftA multi-objective optimal control technique is modified to accommodate changing cost function weights and is used to control a flexible wing aircraft model. Variation of the weights is used to adjust the relative importance of each objective according to either a prescribed function of time or of…17 ppARC-E-DAA-TN64647
- Tool for Turbine Engine Closed-Loop Transient Analysis (TTECTrA) Users' GuideThe tool for turbine engine closed-loop transient analysis (TTECTrA) is a semi-automated control design tool for subsonic aircraft engine simulations. At a specific flight condition, TTECTrA produces a basic controller designed to meet user-defined goals and containing only the fundamental limiters…31 pp20140010478
- Toward improved durability in advanced aircraft engine hot sectionsAdvanced aircraft turbine engine durability needs were addressed in the NASA sponsored Hot Section Technology (HOST) Project. The seven-year project, which was concluded in late 1987, involved representatives from six engineering disciplines who were spread across three work sectors. To address…120 ppNASA-TM-4087
- Towards Intelligent Control for Next Generation CESTOL AircraftThis talk will present the motivation, research approach and status of intelligent control research for Next Generation Cruise Efficient Short Take Off and Landing (CESTOL) aircraft. An introduction to the challenges of CESTOL control will be given, leading into an assessment of potential control…1 pp
- Trajectory Optimization of Electric Aircraft Subject to Subsystem Thermal ConstraintsElectric aircraft pose a unique design challenge in that they lack a simple way to reject waste heat from the power train. While conventional aircraft reject most of their excess heat in the exhaust stream, for electric aircraft this is not an option. To examine the implications of this challenge…16 pp20170009148
- Transcription of the Workshop on General Aviation Advanced Avionics SystemsPapers are presented dealing with the design of reliable, low cost, advanced avionics systems applicable to general aviation in the 1980's and beyond. Sensors, displays, integrated circuits, microprocessors, and minicomputers are among the topics discussed.168 pp19760021145
- Transient flight flutter test of a wing with tip tanksWing flutter was encountered during flight testing of the F2H-2 airplane with full wing tip tanks. As a result, more refined theoretical analysis as well as flight flutter tests were initated to establish corrective measures and to experimentally verify the stability of the improved system. The…6 pp19760003020
- Transient Optimization of a Gas Turbine EngineGas turbine engines are the primary power plants for modern commercial aircraft. Transients prompted by significant changes in thrust or power demand are common and unavoidable. Extreme transient scenarios such as those associated with a go-around during a landing attempt are possible and must be…18 pp
- Transient Optimization of a Gas Turbine EngineGas turbine engines are the primary power plants for modern commercial aircraft. Transients prompted by significant changes in thrust or power demand are common and unavoidable. Extreme transient scenarios such as those associated with a go-around during a landing attempt are possible and must be…14 pp
- Transient Optimization of a Gas Turbine EngineGas turbine engines are the primary power plants for modern commercial aircraft. Transients prompted by significant changes in thrust or power demand are common and unavoidable. Extreme transient scenarios such as those associated with a go-around during a landing attempt are possible and must be…21 pp
- Transition Analysis for the CRM-NLF Wind Tunnel ConfigurationThis paper reports the results of a comprehensive linear stability analysis of the boundary layer flow over the common research model with natural laminar flow (CRM-NLF) aircraft configuration. The flow conditions match selected test conditions from a recent wind tunnel experiment in the National…10 ppAIAA-2021-1431
- Transition Analysis for the CRM-NLF Wind Tunnel ConfigurationThis paper presents the results of an ongoing study into the linear stability characteristics of the boundary layer flow over the common research model with natural laminar flow (CRMNLF) aircraft configuration. The flow conditions match selected test conditions from a recent wind tunnel experiment…19 ppAIAA-2021-1431
- Transonic Aerodynamic and Trim Characteristics of a Multi-engine Delta-wing Airplane ModelWind tunnel testing of two and four engine models of delta wing aircraft for transonic drag rise increment and maximum lift-drag ratio comparison68 pp19660010447
- Transonic aerodynamic characteristics of a tailless fixed-wing supersonic transport modelAerodynamic wind tunnel study of tailless fixed- wing supersonic transport model at transonic speed77 ppNASA-TM-X-1214
- Transonic aerodynamic damping and oscillatory stability in yaw and pitch for a model of a variable-sweep supersonic transport airplaneTransonic aerodynamic stability and damping in yaw and pitch for variable sweep supersonic transport model23 ppNASA-TM-X-1207
- Transonic airfoil design for helicopter rotor applicationsDespite the fact that the flow over a rotor blade is strongly influenced by locally three-dimensional and unsteady effects, practical experience has always demonstrated that substantial improvements in the aerodynamic performance can be gained by improving the steady two-dimensional charateristics…13 pp
- Transonic and Supersonic Flutter Trend Investigation of a Variable-sweep WingWind tunnel analysis of flutter trend for variable sweep aircraft at transonic and supersonic speeds26 pp19660022440
- Transonic Cruise Slotted Wing Design for Commercial Transport Aircraft using CDISCA knowledge-based aerodynamic design method, CDISC, has been extended to enable the computational design of transonic cruise slotted wings for commercial transport aircraft. The cruise slotted wing is a multielement wing concept with a forward main element and an aft flap element, separated to form…36 pp
- Transonic flight flutter tests of a control surface utilizing an impedance response techniqueTransonic flight flutter tests of the XF3H-1 Demon Airplane were conducted utilizing a frequency response technique in which the oscillating rudder provides the means of system excitation. These tests were conducted as a result of a rudder flutter incident in the transonic speed range. The…11 pp19760003026
- Transonic flutter investigation of models of proposed horizontal tails for the X-15 airplaneTransonic flutter analysis of dynamically and elastically scaled models of all-movable horizontal tail of X-15 aircraft40 pp19660024038
- Transonic flutter investigation of models of the all-movable horizontal tail of a fighter airplaneHorizontal tail flutter in fighter aircraft at transonic speeds30 pp19660010452
- Transonic Flutter Investigation of Models of the Sweptback Wing of a Fighter AirplaneTransonic flutter characteristics of sweptback fighter airplane wing models27 pp19660027826
- Transonic flutter investigation of models of the X-15 airplane horizontal tailTransonic flutter analysis of dynamically and elastically scaled models of sweptback, tapered, all-movable horizontal tail of X-15 aircraft35 pp19660024039
- Transonic Flutter Suppression Control Law Design, Analysis and Wind Tunnel ResultsThe benchmark active controls technology and wind tunnel test program at NASA Langley Research Center was started with the objective to investigate the nonlinear, unsteady aerodynamics and active flutter suppression of wings in transonic flow. The paper will present the flutter suppression control…12 pp
- Transonic propulsion system integration analysis at McDonnell Aircraft CompanyThe technology of Computational Fluid Dynamics (CFD) is becoming an important tool in the development of aircraft propulsion systems. Two of the most valuable features of CFD are: (1) quick acquisition of flow field data; and (2) complete description of flow fields, allowing detailed investigation…28 pp19890011572
- Tri-Rotor Aircraft Capable of Vertical Takeoff and Landing and Transitioning to Forward FlightSystems, methods, and devices provide a vehicle, such as an aircraft, with rotors configured to function as a tri-copter for vertical takeoff and landing ("VTOL") and a fixed-wing vehicle for forward flight. One rotor may be mounted at a front of the vehicle fuselage on a hinged structure…32 pp20180006262
- Turbine bypass engine: A new supersonic cruise propulsion conceptEngine performance and mission studies were carried out for a single-spool Turbine Bypass Engine concept. Comparisons were made between the TBE, a conventional single-spool turbojet, and the Pratt & Whitney Variable Stream Control Engine. The airplane assumed for the study was a Mach 2.32…15 pp19810017609
- Turbine Electrified Energy Management (TEEM) For Enabling More Efficient Engine DesignsNASA is investing in Electrified Aircraft Propulsion (EAP) research as part of an effort to assist industry in meeting the future needs of a global aviation market. The integration of electric machines into traditional turbine-based propulsion provides opportunities to change system architectures…16 pp20190002775
- Turbine Engine Hot Section Technology (HOST)Research and plans concerning aircraft gas turbine engine hot section durability problems were discussed. Under the topics of structural analysis, fatigue and fracture, surface protective coatings, combustion, turbine heat transfer, and instrumentation specific points addressed were the thermal and…344 ppNASA-TM-83022
- Turbine Engine Hot Section Technology (HOST) ProjectThe Hot Section Technology (HOST) Project is a NASA-sponsored endeavor to improve the durability of advanced gas turbine engines for commercial and military aircraft. Through improvements in the analytical models and life prediction systems, designs for future hot section components, the combustor…6 pp19890003506
- Turbine Engine Hot Section Technology, 1985The Turbine Engine Section Technology (HOST) Project Office of the Lewis Research Center sponsored a workshop to discuss current research pertinent to turbine engine hot section durability problems. Presentations were made concerning hot section environment and the behavior of combustion liners,…441 ppNASA-CP-2405
- Turbine engine variable geometry deviceA variable geometry device for use with the turbine nozzle of a turbine engine of the type having a support housing and a combustion chamber contained within the support housing. A pair of spaced walls in the support housing define an annular and radially extending nozzle passageway. The outer end…6 pp20080005895
- Turbine heat transferObjectives and approaches to research in turbine heat transfer are discussed. Generally, improvements in the method of determining the hot gas flow through the turbine passage is one area of concern, as is the cooling air flow inside the airfoil, and the methods of predicting the heat transfer…17 pp19850002656
- Turbo- and Hybrid-Electrified Aircraft Propulsion Concepts for Commercial TransportThis review of aircraft electric propulsion architectures conveys that several aircraft system studies have indicated a potential benefit associated with using electrical systems to replace or augment the traditional fuel-based propulsion system. This exciting new approach for designing aircraft…8 pp20180005437
- Turboelectric Aircraft Drive Key Performance Parameters and Functional RequirementsThe purpose of this paper is to propose specific power and efficiency as the key performance parameters for a turboelectric aircraft power system and investigate their impact on the overall aircraft. Key functional requirements are identified that impact the power system design. Breguet range…18 pp20160006295
- Turboelectric Aircraft Drive Key Performance Parameters and Functional RequirementsThe purpose of this presentation is to propose specific power and efficiency as the key performance parameters for a turboelectric aircraft power system and investigate their impact on the overall aircraft. Key functional requirements are identified that impact the power system design. Breguet…17 pp20150021285
- Turboelectric and Hybrid Electric Aircraft Drive Key Performance ParametersNASA has been investigating electrified aircraft propulsion as a means of furthering its goals of reducing fuel burn, emissions, and noise. However, the electric drive components required introduce weight and efficiency penalties at odds with these goals. The purpose of this paper is to propose…19 pp20180005327
- Turboelectric Distributed Propulsion in a Hybrid Wing Body AircraftThe performance of the N3-X, a 300 passenger hybrid wing body (HWB) aircraft with turboelectric distributed propulsion (TeDP), has been analyzed to see if it can meet the 70% fuel burn reduction goal of the NASA Subsonic Fixed Wing project for N+3 generation aircraft. The TeDP system utilizes…20 pp20120000856
- Turbojet and turbofan engines for a mach 3 supersonic transportTurbojet & turbofan engines for supersonic transports12 ppAIAA PAPER-64-244
- Turbulence modeling in aircraft icingThe Icing and Cryogenic Technology Branch develops computational tools which predict ice growth on aircraft surfaces and uses existing CFD technology to evaluate the aerodynamic changes associated with such accretions. Surface roughness, transition location, and laminar, transition, or turbulent…11 pp
- Turbulent boundary layer characteristics of pointed slender bodies of revolution at supersonic speedsTurbulent boundary layer characteristics of pointed slender bodies of revolution at supersonic speeds110 pp19670028755
- Turbulent dispersion of the icing cloud from spray nozzles used in icing tunnelsTo correctly simulate flight in natural icing conditions, the turbulence in an icing simulator must be as low as possible. But some turbulence is required to mix the droplets from the spray nozzles and achieve an icing cloud of uniform liquid water content. The goal for any spray system is to…18 pp19860022116
- Two methods of evaluating climbout noiseGround noise level prediction and measurements during climbout operations of jet transport aircraft8 pp19690002234
- Two-Dimensional Bifurcated Inlet Variable Cowl Lip Test Completed in 10- by 10-Foot Supersonic Wind TunnelResearchers at the NASA Glenn Research Center at Lewis Field successfully tested a variable cowl lip inlet at simulated takeoff conditions in Glenn s 10- by 10-Foot Supersonic Wind Tunnel (10x10 SWT) as part of the High-Speed Research Program. The test was a follow-on to the Two-Dimensional…3 pp
- Two-dimensional Investigation of Five Related NACA Airfoil Sections Designed for Rotating-wing Aircraft44 ppNACA-TN-1922
- Two-Dimensional Wind-Tunnel Investigation of 0.20-Airfoil-Chord Plain Ailerons of Different Contour on an NACA 65(sub 1)-210 Airfoil Section57 ppNACA-MR-L5E26
- Two-Dimensional Wind-Tunnel Investigation of Modified NACA 65(112)-111 Airfoil with 35-Percent-Chord Slotted Flap to Determine Optimum Flap Configuration at Reynolds Number of 2.4 MillionAn investigation has been made in the Langley two-dimensional low-turbulence tunnel to develop the optimum configuration of a 0.35-chord slotted flap on an NACA 65 (112)-111 airfoil section modified by removing the trailing-edge cusp. The results of the investigation indicate that for the optimum…13 ppNACA-RM-L7A02
- Two-Dimensional Wind-Tunnel Investigation of Modified NACA 65(sub 112)-111 Airfoil with 35-Percent-Chord Slotted Flap at Reynolds Numbers up to 25 MillionAn investigation has been made in the Langley two-dimensional low-turbulence tunnels to develop the optimum configuration of a .035-chord slotted flap on an NACA 65(sub(112)-111 airfoil section modified by removing the trailing-edge cusp. Included in the investigation were measurements to determine…19 ppNACA-RM-L7A24
- Two-Dimensional Wind-Tunnel Investigation of Modified NACA 65(sub 112)-111 Airfoil with 35-Percent-Chord Slotted Flap to Determine Pitching-Moment Characteristics and Effects of RoughnessAn investigation has been made in the Langley two-dimensional low-turbulence pressure tunnel to develop the optimum configuration of a 0.35-chord slotted flap on an NACA 65(sub 1120)-111 airfoil section modified by removing the trailing-edge cusp. The section pitching-moment characteristics and the…16 ppNACA-RM-L7B18
- Two-dimensional Wind-tunnel Investigation of Sealed 0.22-airfoil-chord Internally Balanced Ailerons of Different Contour on an NACA 65(112)- 213 Airfoil44 ppNACA-TN-1099
- UAS in the NAS Flight Test Series 3 OverviewThe UAS Integration in the NAS Project is conducting a series of flight tests to acheive the following objectives: 1.) Validate results previously collected during project simulations with live data 2.) Evaluate TCAS IISS interoperability 3.) Test fully integrated system in a relevant live test…44 pp20150015566
- UAS in the NAS Flight Test Series 4 OverviewFlight Test Series 4 (FT4) provides the researchers with an opportunity to expand on the data collected during the first flight tests. Following Flight Test Series 3, additional scripted encounters with different aircraft performance and sensors will be conducted. FT4 is presently planned for…40 pp20160013417
- UAS-NAS Flight Test Series 3: Test Environment ReportThe desire and ability to fly Unmanned Aircraft Systems (UAS) in the National Airspace System (NAS) is of increasing urgency. The application of unmanned aircraft to perform national security, defense, scientific, and emergency management are driving the critical need for less restrictive access by…59 pp20160012546
- Ultra-High Bypass Engine Aeroacoustic StudyA system study was carried out to identify potential advanced aircraft engine concepts and cycles which could be capable of achieving a 5 to 10 EPNdB reduction in community noise level relative to current FAR36 Stage 3 limits for a typical large-capacity commercial transport aircraft. The study was…109 pp20040000741
- Uncertainty Quantification of a Rotorcraft Conceptual Sizing ToolsuiteA computational framework to support the quantification of system uncertainties and sensitivities for rotorcraft applications is presented using the NASA Design and Analysis of Rotorcraft (NDARC) conceptual sizing tool. A 90 passenger conceptual tiltrotor configuration was used for case…24 pp20190000023
- Uncovering Resilient Behavior in the Aviation Safety Reporting System Using Large Language ModelsResiliency is present in everyday life, both in system design and exhibited by the operators that function within these systems. This includes the National Airspace System (NAS) where pilots and controllers make positive decisions and take preventative or corrective actions every day even in unsafe…18 pp
- Uncovering Resilient Behavior in the Aviation Safety Reporting System Using Large Language ModelsResiliency is present in everyday life, both in system design and exhibited by the operators that function within these systems. This includes the National Airspace System (NAS) where pilots and controllers make positive decisions and take preventative or corrective actions every day even in unsafe…7 pp
- Understanding and Controlling Hybrid Electric Gas Turbine Engine Transient DynamicsThe electrification of the gas turbine engine is known to increase the flexibility of aircraft architectures by enabling the generation of electrical power to distribute to other electrically based, thrust producing subsystems. It also has potential for direct performance benefits in the gas…24 ppNASA/TP-20260001365
- Unified results of several analytical and experimental studies of helicopter handling qualities in visual terrain flightThe studies were undertaken to investigate the effects of rotor design parameters, interaxis coupling, and various levels of stability and control augmentation on the flying qualities of helicopters performing low-level, terrain-flying tasks in visual meteorological conditions. Some unified results…16 pp19820015341
- Unified Theory for Aircraft Handling Qualities and Adverse Aircraft-Pilot CouplingA unified theory for aircraft handling qualities and adverse aircraft-pilot coupling or pilot-induced oscillations is introduced. The theory is based on a structural model of the human pilot. A methodology is presented for the prediction of (1) handling qualities levels; (2) pilot-induced…12 ppNASA/CR-1997-207115
- Unsteady flow and dynamic response analyses for helicopter rotor bladesResearch is presented on helicopter rotor blade vibration and on two and three dimensional analyses of unsteady incompressible viscous flow past oscillating helicopter rotor blades. A summary is presented of the two international research collaborations which resulted from the NASA project: the…30 ppNASA-CR-159190
- Unsteady Simulation of a Landing-Gear Flow FieldThis paper presents results of an unsteady Reynolds-averaged Navier-Stokes simulation of a landing-gear flow field. The geometry of the four-wheel landing gear assembly consists of several of the fine details including the oleo-strut, two diagonal struts, a door, yokes/pin and a flat-plate…16 ppAIAA Paper 2002-2411
- Use of grit-type boundary-layer transition trips on wind-tunnel modelsGuidelines applicable to grit-type boundary layer transition trips near leading edges of wind tunnel models22 pp19660026829
- Use of Internal Coolant as a Means of Permitting Increase in Engine Take-Off PowerEngine tests, together with estimates made at Langley Memorial Aeronautical Laboratory, indicate that a 25-percent increase in take-off power can be obtained with present-day aircraft engines without increasing either the knock limit of the fuel or the external cooling requirements of the engine.…15 pp19930093158
- USM3D-ME Analyses Performed in Support of a Wind Tunnel Test of a Boundary-Layer Ingestion ConfigurationBoundary Layer Ingestion (BLI) has been proposed as a technology with the potential to decrease fuel burn. However, one major concern for BLI configurations is the potential degradation of the flow quality, both on the airframe and at the fan face, resulting from the tightly integrated propulsor. A…22 pp
- USM3D-ME Analyses Performed in Support of a Wind Tunnel Test of a Boundary-Layer Ingestion ConfigurationBoundary Layer Ingestion (BLI) has been proposed as a technology with the potential to decrease fuel burn. However, one major concern for BLI configurations is the potential degradation of the flow quality, both on the airframe and at the fan face, resulting from the tightly integrated propulsor. A…32 pp
- V/STOL maneuverability and controlManeuverability and control of V/STOL aircraft in powered-lift flight is studied with specific considerations of maneuvering in forward flight. A review of maneuverability for representative operational mission tasks is presented and covers takeoff, transition, hover, and landing flight phases.…56 ppNASA-TM-85939
- V/STOL tilt rotor aircraft study: Wind tunnel tests of a full scale hingeless prop/rotor designed for the Boeing Model 222 tilt rotor aircraftThe rotor system designed for the Boeing Model 222 tilt rotor aircraft is a soft-in-plane hingeless rotor design, 26 feet in diameter. This rotor has completed two test programs in the NASA Ames 40' X 80' wind tunnel. The first test was a windmilling rotor test on two dynamic wing test stands. The…889 ppNASA-CR-114664
- V/STOL tilt rotor aircraft study. Volume 6: Preliminary design of a composite wing for tilt rotor research aircraftThe results of a study of the use of composite materials in the wing of a tilt rotor aircraft are presented. An all-metal tilt rotor aircraft was first defined to provide a basis for comparing composite with metal structure. A configuration study was then done in which the wing of the metal…130 pp19730021278
- V/STOL tilt rotor aircraft study. Volume 9: Piloted simulator evaluation of the Boeing Vertol model 222 tilt rotor aircraftThe results of a real time piloted simulation to investigate the handling qualities and performance of a tilting rotor aircraft design are presented. The aerodynamic configuration of the aircraft is described. The procedures for conducting the simulator evaluation are reported. Pilot comments of…100 pp19730021280
- V/STOL wind-tunnel testingFactors influencing effective program planning for V/STOL wind-tunnel testing are discussed. The planning sequence itself, which includes a short checklist of considerations that could enhance the value of the tests, is also described. Each of the considerations, choice of wind tunnel, type of…74 ppNASA-TM-85936
- Validation Ice Crystal Icing Engine Test in the Propulsion Systems Laboratory at NASA Glenn Research CenterThe Propulsion Systems Laboratory (PSL) is an existing altitude simulation jet engine test facility located at NASA Glenn Research Center in Cleveland, OH. It was modified in 2012 with the integration of an ice crystal cloud generation system. This paper documents the inaugural ice crystal cloud…34 pp20150002330
- Validation of a Compact Isokinetic Total Water Content Probe for Wind Tunnel Characterization at NASA Glenn Icing Research Tunnel and at NRC Ice Crystal TunnelA new compact isokinetic probe to measure total water content in a wind tunnel environment has been developed. The probe has been previously tested under altitude conditions. This paper presents a comprehensive validation of the probe under a range of liquid water conditions at sea level in the…17 ppGRC-E-DAA-TN42708
- Validation of a Mid-Fidelity Approach for Aircraft Stability and Control CharacterizationThis paper describes an efficient computational approach for aircraft aerodynamic model development intended for use in flight dynamics simulations. A commercial surface-vorticity flow solver called FlightStream is employed to predict performance, stability, and control characteristics for a NASA…16 pp
- Validation of an Active Gear, Flexible Aircraft Take-off and Landing analysis (AGFATL)The results of an analytical investigation using a computer program for active gear, flexible aircraft take off and landing analysis (AGFATL) are compared with experimental data from shaker tests, drop tests, and simulated landing tests to validate the AGFATL computer program. Comparison of…36 ppNASA-TP-2353
- Validation of Methodology for Estimating Aircraft Unsteady Aerodynamic Parameters from Dynamic Wind Tunnel TestsA basic problem in flight dynamics is the mathematical formulation of the aerodynamic model for aircraft. This study is part of an ongoing effort at NASA Langley to develop a more general formulation of the aerodynamic model for aircraft that includes nonlinear unsteady aerodynamics and to develop…11 pp20040085729
- Validation of the gas generator method of calculating jet-engine thrust and evaluation of XB-70-1 airplane engine performance at ground static conditionsValidating gas generator method of calculating jet engine thrust, and evaluation of XB-70-1 engine performance at ground static conditions46 ppNASA-TN-D-7028
- Validation of the Lockheed Martin Morphing Concept with Wind Tunnel TestingThe Morphing Aircraft Structures (MAS) program is a Defense Advanced Research Projects Agency (DARPA) led effort to develop morphing flight vehicles capable of radical shape change in flight. Two performance parameters of interest are loiter time and dash speed as these define the persistence and…17 pp20070018202
- Variable Stiffness Spar Wind-Tunnel Model Development and TestingThe concept of exploiting wing flexibility to improve aerodynamic performance was investigated in the wind tunnel by employing multiple control surfaces and by varying wing structural stiffness via a Variable Stiffness Spar (VSS) mechanism. High design loads compromised the VSS effectiveness…11 pp20040066092
- Variable stream control engine concept for advanced supersonic aircraft: Features and benefitsThe Variable Stream Control Engine is studied for advanced supersonic cruise aircraft. Significant environmental and performance improvements relative to first generation supersonic turbojet engines are cited. Two separate flow streams, each with independent burner and nozzle systems are…12 pp19770011068
- Variation of pitching moment with engine thrust for a twin-engine commercial jet aircraftFlight tests were made to determine the effect of engine net thrust on airplane pitching moment for a twin-engine commercial jet transport in the approach, climbout and descent, and cruise configurations. The results indicate that for all the conditions analyzed, the pitching moment due to thrust…16 ppNASA-TM-X-3569
- Vector plotting as an indication of the approach to flutterA binary flexure-torsion analysis was made to check theoretically a method for predicting flutter which depends on plotting vectorially the amplitudes of response relative to the exciting force and extracting the relevant damping rate. The results of this calculation are given in graphs both of the…10 pp19760003012
- Vehicle integration effects on hypersonic waveridersThe integration of a class of hypersonic high-lift configurations known as waveriders into hypersonic cruise vehicles was evaluated. Waveriders offer advantages in aerodynamic performance and propulsion/airframe integration (PAI) characteristics over conventional hypersonic shapes. A wind-tunnel…132 pp19940029612
- Vehicle technology for civil aviation: The seventies and beyondConference on technological concepts for future transport aircraft developments in civil aviation454 pp19720005346
- Velocity vector control system augmented with direct lift controlA pilot-controlled stability control system that employs direct lift control (spoiler control) with elevator control to control the flight path angle of an aircraft is described. A computer on the aircraft generates an elevator control signal and a spoiler control signal, using a pilot-controlled…6 ppPatent Number: NASA-CASE-LAR-12268-1
- Verifiable Adaptive Control with Analytical Stability Margins by Optimal Control ModificationThis paper presents a verifiable model-reference adaptive control method based on an optimal control formulation for linear uncertain systems. A predictor model is formulated to enable a parameter estimation of the system parametric uncertainty. The adaptation is based on both the tracking error…15 ppARC-E-DAA-TN1962
- Vertical flight path steering system for aircraftDisclosed is a vertical flight path angle steering system for aircraft, utilizing a digital flight control computer which processes pilot control inputs and aircraft response parameters into suitable elevator commands and control information for display to the pilot on a cathode ray tube. The…12 pp20080005888
- Vertical Lift - Not Just For Terrestrial FlightAutonomous vertical lift vehicles hold considerable potential for supporting planetary science and exploration missions. This paper discusses several technical aspects of vertical lift planetary aerial vehicles in general, and specifically addresses technical challenges and work to date examining…26 pp20090023136
- Vertical Takeoff and Landing Vehicle with Increased Cruise EfficiencySystems, methods, and devices are provided that combine an advance vehicle configuration, such as an advanced aircraft configuration, with the infusion of electric propulsion, thereby enabling a four times increase in range and endurance while maintaining a full vertical takeoff and landing…15 pp20180002515
- Very Light Aircraft: Revitalization through CertificationAs the future of the general aviation industry seems to be improving, a cultural paradigm shift may be imminent with the implementation of an advanced, revolutionary transportation system within the United States. By observing the support of government and industry for this idea, near and long term…10 pp19970003131
- Viper cabin-fuselage structural design concept with engine installation and wing structural designThis report describes the process and considerations in designing the cabin, nose, drive shaft, and wing assemblies for the 'Viper' concept aircraft. Interfaces of these assemblies, as well as interfaces with the sections of the aircraft aft of the cabin, are also discussed. The results of the…76 pp19950005892
- Virginia Space Grant Consortium Management of National General Aviation Design CompetitionThis report summarizes the management of the National General Aviation Design Competition on behalf of NASA, the FAA and the Air Force by the Virginia Space Grant Consortium (VSGC) for the time period October 1, 2000 through September 30, 2001. This was the VSGC's seventh and final year of managing…9 pp20020076410
- Virtual Shaping of a Two-dimensional NACA 0015 Airfoil Using Synthetic Jet ActuatorThe Aircraft Morphing Program at NASA Langley envisions an aircraft without conventional control surfaces. Instead of moving control surfaces, the vehicle control systems may be implemented with a combination of propulsive forces, micro surface effectors, and fluidic devices dynamically operated by…11 ppAIAA Paper 2002-3273
- Viscous-flow analysis of a subsonic transport aircraft high-lift system and correlation with flight dataHigh-lift system aerodynamics has been gaining attention in recent years. In an effort to improve aircraft performance, comprehensive studies of multi-element airfoil systems are being undertaken in wind-tunnel and flight experiments. Recent developments in Computational Fluid Dynamics (CFD) offer…88 pp19960003144
- Visions of the Future: Hybrid Electric Aircraft PropulsionThe National Aeronautics and Space Administration (NASA) is investing continually in improving civil aviation. Hybridization of aircraft propulsion is one aspect of a technology suite which will transform future aircraft. In this context, hybrid propulsion is considered a combination of traditional…16 pp20170002633
- Visualization and Quantification of Rotor Tip Vortices in Helicopter FlowsHelicopter aeromechanics encompasses a highly vortical flow field. The vortices generated at each blade tip contain unsteady, complex, three-dimensional structures, which interact with each other, other blades, the fuselage and various components of the helicopter. It is crucial to understand…12 ppARC-E-DAA-TN19713
- Visualization and Quantification of Rotor Tip Vortices in Helicopter FlowsThis paper presents an automated approach for effective extraction, visualization, and quantification of vortex core radii from the Navier-Stokes simulations of a UH-60A rotor in forward flight. We adopt a scaled Q-criterion to determine vortex regions and then perform vortex core profiling in…9 ppARC-E-DAA-TN17322
- Visualizing Flutter Mechanism as Traveling Wave Through Animation of Simulation Results for the Semi-Span Super-Sonic Transport Wind-Tunnel ModelIt has long been recognized that frequency and phasing of structural modes in the presence of airflow play a fundamental role in the occurrence of flutter. Animation of simulation results for the long, slender Semi-Span Super-Sonic Transport (S4T) wind-tunnel model demonstrates that, for the case…12 pp20140011910
- Vortex Flap Technology: a Stability and Control AssessmentA comprehensive low-speed wind tunnel investigation was performed of leading edge vortex flaps applied to representative aircraft configurations. A determination was made of the effects of analytically- and empirically-designed vortex flaps on the static longitudinal and lateral-directional…361 ppNASA-CR-172439
- VTOL and VSTOL handling qualities specifications, an overview of the current statusThe highlights of a comparative analysis between the current helicopter and VSTOL specifications and four representative rotary wing aircraft are presented. Longitudinal, lateral, and directional control power and dynamic stability characteristics were analyzed for hovering conditions. Forward…7 pp19820015335
- Wall-interference assessment and corrections for transonic NACA 0012 airfoil data from various wind tunnelsA nonlinear, four wall, post-test wall interference assessment/correction (WIAC) code was developed for transonic airfoil data from solid wall wind tunnels with flexibly adaptable top and bottom walls. The WIAC code was applied over a broad range of test conditions to four sets of NACA 0012 airfoil…66 ppNASA-TP-3070
- Water tunnel flow visualization and wind tunnel data analysis of the F/A-18Six degree of freedom studies were utilized to extract a band of yawing and rolling moment coefficients from the F/A-18 aircraft flight records. These were compared with 0.06 scale model data obtained in a 16T wind tunnel facility. The results, indicate the flight test yawing moment data exhibit an…206 ppNASA-CR-165859
- Wave rotor demonstrator engine assessmentThe objective of the program was to determine a wave rotor demonstrator engine concept using the Allison 250 series engine. The results of the NASA LERC wave rotor effort were used as a basis for the wave rotor design. A wave rotor topped gas turbine engine was identified which incorporates five…76 pp19960038355
- Wave-Rotor-Enhanced Gas Turbine Engine DemonstratorThe U.S. Army Research Laboratory, NASA Glenn Research Center, and Rolls-Royce Allison are working collaboratively to demonstrate the benefits and viability of a wave-rotor-topped gas turbine engine. The self-cooled wave rotor is predicted to increase the engine overall pressure ratio and peak…14 ppNASA/TM-1999-209459
- Weight and Balance Considerations for Electrified Aircraft Propulsion Applied to the Parallel Electric-Gas Architecture with Synergistic Utilization Scheme (PEGASUS) ConceptThe focus of this research was to understand the impact of batteries and electric motors on the weight and balance of the Parallel Electric-Gas Architecture with Synergistic Utilization Scheme (PEGASUS) concept. Because electrified aircraft propulsion components can comprise a large part of an…16 pp
- Weight estimation techniques for composite airplanes in general aviation industryCurrently available weight estimation methods for general aviation airplanes were investigated. New equations with explicit material properties were developed for the weight estimation of aircraft components such as wing, fuselage and empennage. Regression analysis was applied to the basic…89 pp19860022059
- What is a Tiltrotor? A Fundamental Reexamination of the Tiltrotor Aircraft Design SpaceThe objective of this work is to fundamentally reexamine the design space of tiltrotor aircraft beyond the very successful conventional vehicle configuration with tractor-type twin proprotors that are nacelle-mounted at the wing tips. Previously proposed alternate tiltrotor configurations include…30 ppARC-E-DAA-TN50738
- What Would You Have Done? Learning From Others' Aviation Safety EventsThe capacity to learn from both expected and unexpected events has been identified as a critical component of resilient performance. One’s own experiences, however, are not the only opportunities to learn from these types of events. In the aviation domain, operator-submitted safety event reports…14 pp
- What Would You Have Done? Learning From Others' Aviation Safety EventsThe capacity to learn from both expected and unexpected events has been identified as a critical component of resilient performance. One’s own experiences, however, are not the only opportunities to learn from these types of events. In the aviation domain, operator-submitted safety event reports…6 pp
- Wind tunnel and ground static investigation of a large scale model of a lift/cruise fan V/STOL aircraftAn investigation was conducted in a 40 foot by 80 foot wind tunnel to determine the aerodynamic/propulsion characteristics of a large scale powered model of a lift/cruise fan V/STOL aircraft. The model was equipped with three 36 inch diameter turbotip X376B fans powered by three T58 gas generators.…413 pp19760025090
- Wind Tunnel and Hover Performance Test Results for Multicopter UAS VehiclesThere is currently a lack of published data for the performance of multicopter unmanned aircraft system (UAS) vehicles, such as quadcopters and octocopters, often referred to collectively as drones. With the rapidly increasing popularity of multicopter UAS, there is interest in better…20 ppARC-E-DAA-TN31096
- Wind Tunnel Data Fusion and Immersive Visualization: A Case StudyThis case study describes the process of fusing the data from several wind tunnel experiments into a single coherent visualization. Each experiment was conducted independently and was designed to explore different flow features around airplane landing gear. In the past, it would have been very…5 pp20040086096
- Wind Tunnel Database Development using Modern Experiment Design and Multivariate Orthogonal FunctionsA wind tunnel experiment for characterizing the aerodynamic and propulsion forces and moments acting on a research model airplane is described. The model airplane called the Free-flying Airplane for Sub-scale Experimental Research (FASER), is a modified off-the-shelf radio-controlled model…18 ppAIAA Paper 2003-0653
- Wind Tunnel Design Studies and Technical Evaluation of Advanced Cargo Aircraft ConceptsIn support of aerodynamic studies relating to the design and performance prediction of the National Transonic Facility, the following main tasks were accomplished: (1) estimation of aerodynamic losses of the tunnel circuits, (2) refinement of the high-speed diffuser loss prediction method utilizing…35 pp19760018068
- Wind tunnel evaluation of a truncated NACA 64-621 airfoil for wind turbine applicationsAn experimental program to measure the aerodynamic performance of a NACA 64-621 airfoil with a truncated trailing edge for wind turbine applications has been conducted in the Ohio State University Aeronautical and Astronautical Research Laboratory 6 in. by 21 in. pressurized wind tunnel. The…35 ppNASA-CR-180803
- Wind Tunnel Interference Effects on Tilt Rotor Testing Using Computational Fluid DynamicsExperimental techniques to measure rotorcraft aerodynamic performance are widely used. However, most of them are either unable to capture interference effects from bodies, or require an extremely large computational budget. The objective of the present research is to develop an XV-15 Tiltrotor…96 ppNASA/CR-2015-219086
- Wind Tunnel Interference Effects on Tilt Rotor Testing Using Computational Fluid DynamicsExperimental techniques to measure rotorcraft aerodynamic performance are widely used. However, most of them are either unable to capture interference effects from bodies, or require an extremely large computational budget. The objective of the present research is to develop an XV-15 Tilt Rotor…102 ppARC-E-DAA-TN28935
- Wind tunnel investigation of a simulated gunship helicopter engine-exhaust-windstream interactionA wind tunnel investigation of the engine exhaust and windstream flow interaction on a gunship helicopter model was conducted in the Langley V/STOL tunnel. The investigation utilized a flow visualization technique employing neutrally buoyant helium filled bubbles to determine the cause of exhaust…72 pp19750004869
- Wind tunnel investigation of helicopter rotor wake effects on three helicopter fuselage modelsThe effects of rotor downwash on helicopter fuselage aerodynamic characteristics were investigated. A rotor model for generating the downwash was mounted close to each of three fuselage models. The main report presents the force and moment data in both graphical and tabular form and the pressure…140 ppNASA-TM-X-3185-SUPPL
- Wind tunnel investigation of helicopter-rotor wake effects on three helicopter fuselage modelsThe effects of rotor wake on helicopter fuselage aerodynamic characteristics were investigated in the Langley V/STOL tunnel. Force, moment, and pressure data were obtained on three fuselage models at various combinations of windspeed, sideslip angle, and pitch angle. The data show that the…207 ppNASA-TM-X-3185
- Wind tunnel investigation of longitudinal aerodynamic characteristics of a powered four-duct-propeller VTOL model in transitionWind tunnel stability tests of longitudinal aerodynamic characteristics of powered four-duct propeller VTOL model in transition128 ppNASA-TN-D-3192
- Wind tunnel investigation of supersonic wing-tail flutterA flutter model, consisting of a wing, horizontal tail, and splitter plate/fuselage mechanism, was tested in a 4-foot transonic tunnel in the Mach number range 1.1 to 1.3. Two types of flutter were encountered during the testing: a wing-tail flutter bending-torsion flutter mode. The wing-tail…19 pp19770014086
- Wind Tunnel Investigation of the Effect of Jet-Motor Operation StabilityThe effects of jet-motor operation on the stability and control characteristics of two fighter-type airplanes as determined by wind-tunnel tests of 1/5-scale models are presented. It is shown that the action of the jets is to cause a small loss in stick-fixed stability which is predictable from…25 ppNACA-WR-A-31
- Wind tunnel investigation of vortex flows on F/A-18 configuration at subsonic through transonic speedA wind tunnel experiment was conducted in the David Taylor Research Center 7- by 10-Foot Transonic Tunnel of the wing leading-edge extension (LEX) and forebody vortex flows at subsonic and transonic speeds about a 0.06-scale model of the F/A-18. The primary goal was to improve the understanding and…170 pp19920005750
- Wind tunnel investigations of forebody strakes for yaw control on F/A-18 model at subsonic and transonic speedsWind tunnel investigations have been conducted of forebody strakes for yaw control on 0.06-scale models of the F/A-18 aircraft at free-stream Mach numbers of 0.20 to 0.90. The testing was conducted in the 7- by 10-Foot Transonic Tunnel at the David Taylor Research Center and the Langley 7- by…108 pp19940012100
- Wind tunnel measurements of forward speed effects on jet noise from suppressor nozzles and comparison with flight test dataThe results of a test program conducted in the NASA Ames 40- by 80-Foot Wind Tunnel to determine the effect of forward speed on the noise levels emanating from a conical ejector nozzle, a 32-spoke suppressor nozzle, and a 104-elliptical-tube suppressor nozzle are reported. It is shown that noise…12 ppNASA-TM-X-62449
- Wind Tunnel Model Design for Sonic Boom Studies of Nozzle Jet Flows with Shock InteractionsNASA and the U.S. aerospace industry are performing studies of supersonic aircraft concepts with low sonic boom pressure signatures. The computational analyses of modern aircraft designs have matured to the point where there is confidence in the prediction of the pressure signature from the front…ARC-E-DAA-TN28746
- Wind Tunnel of the Bucharest Polytechnic InstituteThis report describes the Bucharest wind tunnel and presents numerous photographs and diagrams. The wind tunnel is of the closed- circuit type, the return being symmetrical with respect t o the longitudinal axis of the tunnel. Th e tunnel is of the horizontal type with a diameter of 3. 2 m (10.…10 ppNACA-TM-651
- Wind tunnel test data for wing trailing vortex flow surveyData are presented on velocity measurements made with hot wire anemometers in the wake of a model of the CV-990 aircraft and a rectangular wing in the NASA-Ames 2.14x3.05 meter (7- by 10-foot) wind tunnels. Variables included angle of attack, tunnel speed and axial distance up to 12 chord lengths…95 ppNASA-TM-X-62148
- Wind tunnel test of a variable-diameter tiltrotor (VDTR) modelThis report documents the results from a wind tunnel test of a 1/6th scale Variable Diameter Tiltrotor (VDTR). This test was a joint effort of NASA Ames and Sikorsky Aircraft. The objective was to evaluate the aeroelastic and performance characteristics of the VDTR in conversion, hover, and cruise.…238 ppNASA-CR-177629
- Wind Tunnel Test of an RPV with Shape-Change Control Effector and Sensor ArraysA variety of novel control effector concepts have recently emerged that may enable new approaches to flight control. In particular, the potential exists to shift the composition of the typical aircraft control effector suite from a small number of high authority, specialized devices (rudder,…12 ppAIAA Paper 2004-5114
- Wind Tunnel Testing of a One-Dimensional Laser Beam Scanning and Laser Sheet Approach to Shock SensingA 15- by 15-cm supersonic wind tunnel application of a one-dimensional laser beam scanning approach to shock sensing is presented. The measurement system design allowed easy switching between a focused beam and a laser sheet mode for comparison purposes. The scanning results were compared to images…26 pp20120007093
- Wind tunnel testing of low-drag airfoilsResults are presented for the measured performance recently obtained on several airfoil concepts designed to achieve low drag by maintaining extensive regions of laminar flow without compromising high-lift performance. The wind tunnel results extend from subsonic to transonic speeds and include…40 pp19880014357
- Wind Tunnel Testing Techniques for a Tandem Tilt-Wing, Distributed Electric Propulsion VTOL AircraftUrban Air Mobility (UAM) vertical takeoff and landing (VTOL) aircraftdesigns frequently include multiple distributed propulsors, complex wing-propulsor aerodynamics, significant airframe configuration changes during normal flight operations, and no historical database regarding the best ways to…23 pp
- Wind Tunnel Tests of Ailerons at Various Speeds I : Ailerons of 0.20 Airfoil Chord and True Contour with 0.35 Aileron-chord Extreme Blunt Nose Balance on the NACA 66,2-216 AirfoilHinge-moment, lift, and pressure-distribution measurements were made in the two-dimensional test section of the NACA stability tunnel on a blunt-nose balance-type aileron on an NACA 66,2-216 airfoil at speeds up to 360 miles per hour corresponding to a Mach number of 0.475. The tests were made…77 ppNACA-WR-L-431
- Wind tunnel tests of an NACA 23021 airfoil equipped with a slotted extensible and a plain extensible flapAn investigation has been made in the NACA 7- by 10-foot wind tunnel of a large chord NACA 23021 airfoil equipped with two arrangements of a completely extended 15 percent chord extensible flap. One of the flaps had a faired juncture, without a gap; the other was provided with a slot between the…11 ppNACA-TN-782
- Wind tunnel tests of high-lift systems for advanced transports using high-aspect-ratio supercritical wingsThe wind tunnel testing of an advanced technology high lift system for a wide body and a narrow body transport incorporating high aspect ratio supercritical wings is described. This testing has added to the very limited low speed high Reynolds number data base for this class or aircraft. The…189 pp19840020673
- Wind Tunnel to Atmospheric Mapping for Static Aeroelastic ScalingWind tunnel to Atmospheric Mapping (WAM) is a methodology for scaling and testing a static aeroelastic wind tunnel model. The WAM procedure employs scaling laws to define a wind tunnel model and wind tunnel test points such that the static aeroelastic flight test data and wind tunnel data will be…12 ppAIAA Paper 2004-2044
- Wind Tunnel-Based Aerodynamic Model Identification for a Tilt-Wing, Distributed Electric Propulsion AircraftThis paper describes the methodology used to develop a high-fidelity aerodynamic model for the Langley Aerodrome No. 8 (LA-8) tandem tilt-wing, distributed electric propulsion, vertical takeoff and landing aircraft. Electric vertical takeoff and landing (eVTOL) vehicle configurations exhibit…26 pp
- Wind tunnel/flight data correlation for the Boeing 737-100 transport airplaneA brief wind-tunnel/flight data correlation for the Boeing 737-100 airplane was made. The results showed excellent agreement between wind-tunnel and flight trimmed drag polars at Mach numbers less than 0.67. The wind-tunnel data predicted larger drag increments due to compressibility and a…19 ppNASA-TM-X-72715
- Wind-tunnel boundary interference for V/STOL TESTINGThe wake skew angle used in applying the theory of NASA TR R-124 to data correction should be such that the angular deflection of the wake vorticity from the horizontal is one-half that calculated from momentum theory at the lifting element. This usage is in contrast to that of the original paper…26 pp
- Wind-Tunnel Evaluation of the Effect of Blade Nonstructural Mass Distribution on Helicopter Fixed-System LoadsThis report provides data obtained during a wind-tunnel test conducted to investigate parametrically the effect of blade nonstructural mass on helicopter fixed-system vibratory loads. The data were obtained with aeroelastically scaled model rotor blades that allowed for the addition of concentrated…250 pp19980018152
- Wind-tunnel free-flight investigation of a model of a forward-swept-wing fighter configurationA wind-tunnel free-flight investigation was conducted to study the dynamic stability characteristics of a model of a forward-swept-wing fighter-airplane configuration at high angles of attack. Various other wind-tunnel techniques employed in the study included static- and dynamic-…72 pp19840009116
- Wind-tunnel investigation at high subsonic speeds of the effects on static stability characteristics of various modifications to a swept-wing fighter-type airplane modelWind tunnel investigations of effect on static stability of modifications to swept wing fighter aircraft model110 ppNACA-RM-L57A31
- WIND-TUNNEL INVESTIGATION AT SUBSONIC AND SUPERSONIC SPEEDS OF A MODEL OF A TAILLESS FIGHTER AIRPLANE EMPLOYING A LOW-ASPECT-RATIO SWEPT-BACK WING-STABILITY AND CONTROLSubsonic and supersonic wind tunnel study of low aspect ratio sweptback wing tailless fighter aircraft model/stability and control55 ppNACA-RM-A52J30
- Wind-tunnel investigation of a flush airdata system at Mach numbers from 0.7 to 1.4Flush pressure orifices installed on the nose section of a 1/7-scale model of the F-14 airplane were evaluated for use as a flush airdata system (FADS). Wing-tunnel tests were conducted in the 11- by 11-ft Unitary Wind Tunnel at NASA Ames Research Center. A full-scale FADS of the same configuration…38 ppNASA-TM-101697
- Wind-Tunnel Investigation of a Low-Drag Airfoil Section with a Double Slotted FlapTests were made of an 0.309-chord double-slotted flap on an NACA 65, 3-118, a equals 1.0 airfoil section to determine drag, lift, and pitching-moment characteristics for a range of flap deflections. Results indicate that combination of a low-drag airfoil and a double-slotted flap, of which the two…20 ppNACA-ACR-3I20
- Wind-Tunnel Investigation of a Rectangular NACA 2212 Airfoil with Semispan Ailerons and with Nonperforated, Balanced Double Split Flaps for Use as Aerodynamic BrakesFlat-plate flaps with no wing cutouts and flaps having Clark Y sections with corresponding cutouts made in wing were tested for various flap deflections, chord-wise locations, and gaps between flaps and airfoil contour. The drag was slightly lower for wing with airfoil section flaps. Satisfactory…68 ppNACA-ARR-L5B17
- Wind-Tunnel Investigation of Air Inlet and Outlet Openings for Aircraft, Special ReportAn investigation was made in the NACA 5-foot vertical wind tunnel of a large variety of duct inlets and outlets to obtain information relative to their design for the cooling or the ventilation systems on aircraft. Most of the tests were of openings in a flat plate but, in order to determine the…71 ppNACA-SR-95
- Wind-Tunnel Investigation of an Advanced General Aviation Canard ConfigurationWind-tunnel tests of a model of an advanced canard configuration designed for general aviation were conducted in the Langley 30- by 60-Foot Tunnel. The objective of the tests was to determine the aerodynamic stability and control characteristics of the configuration for a large range of angles of…48 pp19840013471
- Wind-tunnel investigation of an NACA 23012 airfoil with 30 percent-chord venetian-blind flapsReport presents the results of an investigation made in the NACA 7 by 10-foot wind tunnel of a NACA 23012 airfoil with 30-percent-chord venetian-blind flaps having one, two, three, and four slats of Clark y section. The three-slat arrangements was aerodynamically the best of those tested but showed…8 ppNACA-TR-742
- Wind-Tunnel Investigation of an NACA 23012 Airfoil with a 0.30-Airfoil-Chord Double Slotted Flap51 ppNACA-ARR-3L10
- Wind-tunnel investigation of an NACA 23012 airfoil with a Handley Page slat and two flap arrangements25 ppNACA-WR-L-261
- Wind-tunnel investigation of an NACA 23012 airfoil with several arrangements of slotted flaps with extended lipsAn investigation was made in the NACA 7- by 10-foot wind tunnel to determine the effect of slot-lip location on the aerodynamic section characteristics of an NACA 23012 airfoil with a 30-percent-chord slotted flap. Tests were made with slot lips located at 90 and 100 percent of the airfoil chord…21 ppNACA-TN-808
- Wind-Tunnel Investigation of an NACA 23012 Airfoil with Various Arrangements of Slotted FlapsAn investigation was made in the 7 by 10-foot wind tunnel and in the variable-density wind tunnel of the NACA 23012 airfoil with various slotted-flap arrangements. The purpose of the investigation in the 7 by 10-foot wind tunnel was to determine the airfoil section aerodynamic characteristics as…36 ppNACA-TR-664
- Wind-Tunnel Investigation of an NACA 23021 Airfoil with a 0.32-Airfoil-Chord Double Slotted FlapAn investigation was made in the LMAL 7- by 10-foot wind tunnel of a NACA 23021 airfoil with a double slotted flap having a chord 32 percent of the airfoil chord (0.32c) to determine the aerodynamic section characteristics with the flaps deflected at various positions. The effects of moving the…54 ppNACA-ARR-L4J05
- Wind-tunnel investigation of an NACA 23030 airfoil with various arrangements of slotted flapsAN investigation was made of a large-chord NACA 23030 airfoil with a 40- and a 25.66 percent-chord slotted flap to determine the section aerodynamic characteristics of the airfoil affected by flap chord, slot shape, flap position, and flap deflection. The flap positions for maximum lift, the…33 ppNACA-TN-755
- Wind-Tunnel Investigation of an NACA 66,2-216 Low-Drag Wing with Split Flaps of Various Sizes, Special ReportAn investigation was conducted in the NACA 19-foot pressure wind tunnel of a rectangular wing having NACA 66, 2-216 low-drag airfoil sections and various sizes of simple split flaps. The purpose of the investigation was, primarily, to determine the influence of these flap installations on the…31 ppNACA-SR-208
- Wind-tunnel investigation of an NACA full-span high-lift lateral-control combination I : section characteristics, NACA 23012 airfoil31 ppNACA-WR-L-288
- Wind-Tunnel Investigation of an NACA Low-Drag Tapered Wing with Straight Trailing Edge and Simple Split Flaps, Special ReportAn investigation was conducted in the NACA 19-foot pressure wind tunnel of a tapered wing with straight railing edge having NACA 66 series low-drag airfoil sections and equipped with full-span and partial-span simple split flaps. The airfoil sections used were the NACA 66,2-116 at the root and the…21 ppNACA-ACR-212
- Wind-Tunnel Investigation of Control-Surface Characteristics XV : Various Contour Modifications of a 0.30-Airfoil-Chord Plain Flap on an NACA 66(215)-014 Airfoil43 ppNACA-ACR-3L20
- Wind-Tunnel Investigation of Control-Surface Characteristics XVI : Pressure Distribution over an NACA 0009 Airfoil with 0.30-Airfoil-Chord Beveled-Trailing-Edge Flaps71 ppNACA-WR-L-205
- Wind-Tunnel Investigation of Control-Surface Characteristics XVII : Beveled-Trailing-Edge Flaps of 0.20, 0.30, and 0.40 Airfoil Chord on an NACA 0009 Airfoil53 ppNACA-ACR-L4D12
- Wind-tunnel investigation of highly maneuverable supersonic V/STOL fighterResults from the initial wind-tunnel test of a large-scale, highly maneuverable supersonic V/STOL fighter model in the Ames 40- by 80-foot wind tunnel are summarized. The STOL configuration which was tested combined upper surface blowing and spanwise blowing to improve the lift characteristics over…23 ppNASA-TM-78599
- Wind-tunnel investigation of NACA 23012 airfoil with various arrangements of slotted flapsAn investigation was made in the NACA 7 by 10-foot wind tunnel of a large-chord NACA 23012 airfoil with several arrangements of 25.66 percent chord slotted flaps to determine the section aerodynamic characteristics as affected by slot shape, flap shape, flap location, and flap deflection. The flap…24 ppNACA-TR-677
- Wind-tunnel investigation of NACA 23012, 23021, and 23030 airfoils equipped with 40-percent-chord double slotted flapsReport presents the results of an investigation conducted in the NACA 7 by 10-foot win tunnel to determine the effect of the deflection of main and auxiliary slotted flaps on the aerodynamic section characteristics of large-chord NACA 23012, 23021, 23030 airfoils equipped with 40-percent-chord…37 ppNACA-TR-723
- Wind-tunnel investigation of NACA 23012, 23021, and 23030 airfoils with various sizes of split flapReport presents the results of an investigation made in the NACA 7 by 10-foot wind tunnel of large-chord NACA and 23021, and 23030 airfoils with split flaps 10, 20, 30, and 40 percent of the wing chord to determine the section aerodynamic characteristics of the airfoils as affected by airfoil…18 ppNACA-TR-668
- Wind-Tunnel Investigation of Perforated Split Flaps for Use as Dive Brakes on a Tapered NACA 23012 AirfoilAerodynamic characteristics of a tapered NACA 23012 airfoil with single and double perforated split flaps have been determined in the NACA 7- by 10-foot wind tunnel. Dynamic pressure surveys were made behind the airfoil at the approximate location of the tail in order to determine the extent and…23 ppNACA-WR-L-373
- Wind-tunnel investigation of seven thin NACA airfoil sections to determine optimum double-slotted-flap configurations76 ppNACA-TN-1545
- Wind-tunnel investigation of steady-state aerodynamics of a composite-lift VTOL aircraft modelWind tunnel investigation of steady state aerodynamics of composite lift VTOL aircraft model combining rotary and fixed wings40 pp19690018719
- Wind-tunnel investigation of the boundary layer on an NACA 0009 airfoil having 0.25- and 0.50- airfoil chord plain sealed flaps54 ppNACA-TN-1574
- Wind-Tunnel Investigation of the Lift Characteristics of an NACA 27-212 Airfoil Equipped with Two Types of Flap, Special ReportAn investigation has been made in the NACA 7- by 10-foot wind tunnel of a large chord NACA 27-212 airfoil with a 20% chord split flap and with two arrangements of a 25.66% chord slotted flap to determine the section lift characteristics as affected by flap deflection for the split flap and as…24 ppNACA-SR-159
- Wind-Tunnel Investigations of Blunt-Body Drag Reduction Using Forebody Surface RoughnessThis paper presents results of wind-tunnel tests that demonstrate a novel drag reduction technique for blunt-based vehicles. For these tests, the forebody roughness of a blunt-based model was modified using micomachined surface overlays. As forebody roughness increases, boundary layer at the model…36 pp20010014167
- Wind-tunnel of three lateral-control devices in combination with a full-span slotted flap on an NACA 23012 airfoilA large-chord NACA 23012 airfoil was tested. The airfoil extended completely across the test section, and two-dimensional flow was approximated. The model was fitted with a full-span slotted flap having a chord 25.66 percent of the airfoil chord. The ailerons investigated extended over the entire…26 ppNACA-TN-659
- Wind-tunnel simulation of store jettison with the aid of magnetic artificial gravityA method employed in the simulation of jettison of stores from aircraft involving small scale wind-tunnel drop tests from a model of the parent aircraft is described. Proper scaling of such experiments generally dictates that the gravitational acceleration should ideally be a test variable. A…156 ppNASA-CR-1955
- Wind-tunnel studies of advanced cargo aircraft conceptsAccomplishments in vortex flap research are summarized. A singular feature of the vortex flap is that, throughout the range of angle of attack range, the flow type remains qualitatively unchanged. Accordingly, no large or sudden change in the aerodynamic characteristics, as happens when forcibly…18 ppNASA-CR-164833
- Wind-tunnel testing of VTOL and STOL aircraftThe basic concepts of wind-tunnel boundary interference are discussed and the development of the theory for VTOL-STOL aircraft is described. Features affecting the wall interference, such as wake roll-up, configuration differences, recirculation limits, and interference nonuniformity, are…81 pp19780022097
- Wind-tunnel Tests of a Wing with a Trailing-edge Auxiliary Airfoil Used as a FlapThis report gives the characteristics of a wing with an auxiliary airfoil mounted near its trailing edge and used as a flap. The tests were made with a 10 by 60 inch Clark Y main airfoil and an NACA 0012 flap having a chord equal to 15 percent of the main wing chord. The axis of the flap in all…14 ppNACA-TN-524
- Wind-tunnel Tests of Four Curtiss Propellers Embodying Different Blade SectionsTests of four 10-foot propellers were made in the propeller-research tunnel for the Army Air Corps to check flight and static thrust test results made on several propellers embodying Clark Y and modified NACA 16-series sections. These propellers were identical as to diameter and activity factor and…26 ppNACA-WR-L-569
- Wind-tunnel Tests of the NACA 45-125 Airfoil: A Thick Airfoil for High-Speed AirplanesInvestigations of the pressure distribution, the profile drag, and the location of transition for a 30-inch-chord 25-percent-thick N.A,C.A. 45-125 airfoil were made in the N.A.C.A 8-foot high-speed wind tunnel for the purpose of aiding in the development of a thick wing for high-speed airplanes.…16 ppNACA-SR-138
- Wind-tunnel tests of the XV-15 tilt rotor aircraftThe XV-15 aircraft was tested in the Ames 40 by 80 Foot Wind Tunnel for preliminary evaluation of aerodynamic and aeroelastic characteristics prior to flight. The tests were undertaken to investigate the aircraft performance, stability, control and structural loads for flight modes from helicopter…138 ppNASA-TM-81177
- Wing Configuration Impact on Design Optimums for a Subsonic Passenger TransportThis study sought to compare four aircraft wing configurations at a conceptual level using a multi-disciplinary optimization (MDO) process. The MDO framework used was created by Georgia Institute of Technology and Virginia Polytechnic Institute and State University. They created a…12 ppAIAA-2014-0185
- Wing design for a civil tiltrotor transport aircraftThe goal of this research is the proper tailoring of the civil tiltrotor's composite wing-box structure leading to a minimum-weight wing design. With focus on the structural design, the wing's aerodynamic shape and the rotor-pylon system are held fixed. The initial design requirement on drag…6 pp19950011675
- Wing design for a civil tiltrotor transport aircraft: A preliminary studyA preliminary study was conducted on the design of the wing-box structure for a civil tiltrotor transport aircraft. The wing structural weight is to be minimized subject to structural and aeroelastic constraints. The composite wing-box structure is composed of skin, stringers, ribs, and spars. The…2 pp19940023414
- Wing-tip vanes as vortex attenuation and induced drag reduction devicesAnalytical studies have been conducted to examine the feasibility of utilizing wing tip turbines to remove swirl from the wing trailing vortex, and hence reduce the potential for upset of following aircraft. Energy recovery from the turbines is also analyzed. A computer routine has been developed…12 pp19760003924
- Within-Tunnel Variations in Pressure Data for Three Transonic Wind TunnelsThis paper compares the results of pressure measurements made on the same test article with the same test matrix in three transonic wind tunnels. A comparison is presented of the unexplained variance associated with polar replicates acquired in each tunnel. The impact of a significance component of…39 ppNF1676L-18111
- Worst-Case Flutter Margins from F/A-18 Aircraft Aeroelastic DataAn approach for computing worst-case flutter margins has been formulated in a robust stability framework. Uncertainty operators are included with a linear model to describe modeling errors and flight variations. The structured singular value, micron, computes a stability margin which directly…11 pp19980036976
- X-29A Lateral-Directional Stability and Control Derivatives Extracted From High-Angle-of-Attack Flight DataThe lateral-directional stability and control derivatives of the X-29A number 2 are extracted from flight data over an angle-of-attack range of 4 degrees to 53 degrees using a parameter identification algorithm. The algorithm uses the linearized aircraft equations of motion and a maximum likelihood…41 ppNASA-TP-3664
- X-29A longitudinal and directional force and moment supplemental transonic wind tunnel test resultsAerodynamic data from NASA Ames Research Center's 11-Foot Transonic Wind Tunnel are plotted for the 1/8-scale X-29A forward-swept wing aircraft model. Eleven configurations were tested to provide supplemental data to investigate single surface failure modes, complex nonlinearities, and model…289 ppNASA-TM-85909
- X-29A technology demonstrator flight test program overviewAn overview of the X-29A functional flight program and concept evaluation program is presented, including some of the unique and different preparations for the first flight. Included are a discussion of the many organizational responsibilities and a description of the program management structure…17 pp19860016856
- X-37 Flight Demonstrator: Approach and Landing Test Vehicle Flight Test ApproachApproach and Lending Test Vehicle (ALTV) reduces risk to the X-37 orbital vehicle (OV) flight program by: Testing a subset of OV technologies in a critical portion of the flight envelope. Validating the calculated air data system (CADS) performance/subsonic aerodynamic database. Demonstrating OV…20040037790
- X-37 Flight Demonstrator: X-40A Flight Test ApproachThe flight test objectives are: Evaluate calculated air data system (CADS) experiment. Evaluate Honeywell SIGI (GPS/INS) under flight conditions. Flight operation control center (FOCC) site integration and flight test operations. Flight test and tune GN&C algorithms. Conduct PID maneuvers to…
- X-43 Hypersonic Vehicle Technology DevelopmentNASA recently completed two major programs in Hypersonics: Hyper-X, with the record-breaking flights of the X-43A, and the Next Generation Launch Technology (NGLT) Program. The X-43A flights, the culmination of the Hyper-X Program, were the first-ever examples of a scramjet engine propelling a…10 pp20050239566
- X-48B Flight Test Progress OverviewThe results of a series of 39 flight tests of the X-48B Low Speed Vehicle (LSV) performed at the NASA Dryden Flight Research Center from July 2007 through December 2008 are reported here. The goal of these tests is to evaluate the aerodynamic and controls and dynamics performance of the subscale…17 pp20090005939
- X-48B Preliminary Flight Test ResultsThis slide presentation reviews the preliminary Flight tests of the X-48B development program. The X-48B is a blended wing body aircraft that is being used to test various features of the BWB concept. The research concerns the following: (1) Turbofan Development, (2) Intelligent Flight Control and…25 pp20090036791
- X-48B System Flight TestProvides an overview of the X-48B prototype system flight test including vehicle characteristics and configuration. There are two X-48B Vehicles: the first, Vehicle 1, is the wind tunnel and flight test model. The second, Vehicle 2, provides the primary flight test. In mid-May 2006 the research…1 pp
- X-57 and Whirl Flutter DiscussionNo abstract available11 pp20180002829
- X-59 Air Data Probe Calibration Wind Tunnel TestNASA's aeronautical innovators are working with Lockheed Martin to design and build a supersonic X-plane, the X-59, under the the Low Boom Flight Demonstrator (LBFD) Project, that produces a gentle thump rather than a loud sonic boom. The plane will be used to collect human response data over…29 pp
- YAV-8B reaction control system bleed and control power usage in hover and transitionUsing a calibrated Rolls-Royce Pegasus engine and existing aircraft instrumentation and pressure taps, total and individual nozzle reaction control system (RCS) bleed flow rates have been measured on a YAV-8B Harrier during typical short takeoff, transition, hover, and vertical landing maneuvers.…48 ppNASA-TM-104021