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!- P- NASA CR-1146 THE EFFECT OF ENGINE COMPONENT NOISE ON V/STOL AIRCRAFT NOISE CONTOURS by R.G.
FOGG GENERAL ELECTRIC COMPANY 74-206- 7 ENGINE - - T- E EFFEC OF- (AS-Ci -1 146-87) AIRCRAFT NOISE NOISE ON V/STOL COMPONENT (General Electric Co.) 11:6-f ICONTOURS 01C Unclas CSCL lHC $9.00 36272 G3/02 prepared for ADMINISTRATION NATIONAL AERONAUTICS AND SPACE NASA - Ames Research Center
CONTRACT NAS2-5462
1. Report No. 2. Government Accession No. 3. Recipient's Catalog No.
NASA CR-114687 4. Title and Subtitle 5. Report Date EFFECT OF ENGINE COMPONENT NOISE ON V/STOL February THE 6. Performing Organization Code NOISE CONTOURS AIRCRAFT No.
Author(s) 8. Performing Organization Report 7.
R73 AEG 306 R. G. Fogg 10. Work Unit No.
9. Performing Organization Name and Address General Electric Company 11. Contract or Grant No.
Evendale, Ohio 45215 NAS2-5462 13. Type of Report and Period Covered 12. Sponsoring Agency Name and Address Contractor Report Aeronautics and Space Administration National Washington, D C. 20546 14. Sponsoring Agency Code Washington, D. C. 20546 15. Supplementary Notes Center NASA Ames Research D. H. Hickey, Project Manager, Moffett Field, California 94035 16. Abstract contours to show the study of fly-over noise using noise An analytical of approach and path parameters. The method effects of varying airplane these engine component noise spectra and-exercise was to synthesize individual and total along given flight paths to measure the components effect as a function of noise footprint area.
fly-over I utilized a research was carried out in two phases. Phase The study aircraft. The effect and Phase II used an advanced VTOL type aircraft inlet and exhaust sections of the of cross flow was considered for both engine.
17. Key Words (Suggested by Author(s)) 18. Distribution Statement V/STOL Aircraft Noise Contours 19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price* Unclassified Unclassified / / V * For sale by the National Technical Information Service, Springfield, Virginia 22151 NASA-C-168 (Rev. 6-7t) I Table of Contents Page Number Section Title I Summary II Introduction III Calculation Techniques IV Engine Component Noise V Aircraft Characteristics VI Aircraft Noise Contours 11 VII Noise Component Analysis VIII Effect of Additional Suppression IX Conclusions X Nomenclature XI References PRECEDING PAGE BLANK NOT FILMED iii List of Tables and Figures Number Title Page Number I Table of Thermodynamic Parameters II Table of Engine Component Definitions Typical Cross Flow Corrections - Inlet Typical Cross Flow Corrections - Exhaust 3 Plan View Phase I Aircraft 4 Phase I Aircraft Thrust Vector Angular Reference 5 Phase I Aircraft Low Rise Take-off Path 6 Phase I Aircraft High Rise Take-off Path Phase I Aircraft Low Rise Take-off Velocity 8 Phase I Aircraft High Rise Take-off Velocity Phase I Aircraft Low Rise Take-off Power Setting 33 Phase IAircraft High Rise Take-off Power Setting 34 Phase I Aircraft Low Rise Take-off Louver Schedule 35 12 Phase I Aircraft High Rise Take-off Louver Schedule 36 Phase I Aircraft Low Rise Take-off Attitude Schedule 37 Phase I Aircraft High Rise Take-off Attitude Schedule 15 Phase I Aircraft Low Rise Approach Path 16 Phase I Aircraft High Rise Approach Path Phase I Aircraft Low Rise Approach Velocity 18 Phase I Aircraft High Rise Approach Velocity Phase I Aircraft Low Rise Approach Louver Schedule Phase I Aircraft High Rise Approach Louver Schedule Phase I Aircraft Low Rise Approach Power Setting Phase I Aircraft High Rise Approach Power Setting Phase I Aircraft Low Rise Approach Attitude Schedule Phase I Aircraft High Rise Approach Attitude Schedule 48 Phase II Plan View and Thrust Vector Angular Reference Phase II Aircraft Take-off Path Phase II Aircraft Approach Path Phase II Aircraft Take-off Velocity 29 Phase II Aircraft Approach Velocity Phase II Aircraft Take-off Power Setting iv List of Tables and Figures - Continued Number Title Page Number Phase II Aircraft Approach Power Setting 32 Phase II Aircraft Take-off Attitude Schedule Phase II Aircraft Approach Attitude Schedule 34 Phase II Aircraft Take-off Thrust Vector Schedules 35 Phase II Aircraft Approach Thrust Vector Schedules 36 Phase I Aircraft Low Rise Take-off PNL Contour Phase I Aircraft High Rise Take-off PNL Contour 61 Phase I Aircraft Low Rise Take-off EPNL Contour 39 Phase I Aircraft High Rise Take-off EPNL Contour 63 40 Phase I Aircraft Take-off 95 PNL Contour Comparison 64 41 Phase I Aircraft Low Descent Approach PNL Contour 42 Phase I Aircraft High Descent Approach PNL Contour 43 Phase I Aircraft Low Descent Approach DPNL Contour Phase I Aircraft High Descent Approach EPNL Contour 68 Phase I. Aircraft Approach 95 PNL Contour Comparison Phase II Aircraft Generalized Source Location on Aircraft Path Phase II Aircraft Take-off PNL Contour 48 Phase II VTOL Aircraft Approach PNL Contour 72 49 PNL Contour Area - Take-off Operation - Comparison Phase I 73 and Phase II.
High-Rise 50 PNL Contour Area - Approach Operation - Comparison Phase I 74 High Descent and Phase II.
Phase I Aircraft Engine Component Noise Fan 75 Inlet 52 Phase I Aircraft Component Noise Fan Exhaust 76 53 Phase I Aircraft Component Noise Jet Exhaust 77 Phase I Aircraft Component Noise Core Turbine 78 Phase I Aircraft Component Noise Core Compressor 56 Phase I Aircraft Take-off Flyover PNL, Fan Inlet 80 Component, Centerline Mike 57 Phase I Aircraft Take-off Flyover PNL, Fan Exhaust 81 Component, Centerline Mike V List of Tables and Figures - Continued Number Title Page Number Phase I Aircraft Take-off Flyover PNL, Fan Exhaust Component, Centerline Mike Phase I Aircraft Take-off Flyover PNL, Turbine- Turbomachinerys Component, Centerline Mike Phase I Aircraft Take-off Flyover PNL, Compressor Inlet Component, Centerline Mike Phase I Aircraft Take-off Flyover PNL, Combined Components, Centerline Mike Phase I Aircract Take-off Flyover PHL, Fan Inlet Component, 740 ft. Sideline Mike Phase I Aircraft Take-off Flyover PNL, Fan Exhaust Component, 740 ft Sideline Mike Phase I Aircraft Take-off Flyover PNL, Combined Jet Component, 740 ft Sideline Mike Phase I Aircraft Take-off Flyover PNL, Turbine - 89 Turbomachinery Component, 740 ft Sideline Mike 66 Phase I Aircraft Take-off Flyover PNL, Compressor Inlet 90 Component, 740 ft Sideline Mike Phase I Aircraft Take-off Flyover PNL, Combined Com- ponents, 740 ft Sideline Mike 68 Phase I Aircraft Approach Flyover PNL, Fan Inlet Centerline Mike Component, Phase I Aircraft Approach Flyover PNL, Fan Exhaust Component, Centerline Mike Phase I Aircraft Approach Flyover PNL, Combined Jet Component, Centerline Mike Phase I Aircraft Approach Flyover PNL, Turbine - Turbomachinery Component, Centerline Mike 72 Phase I Aircraft Approach Flyover PNL, Compressor Inlet Component, Centerline Mike 73 Phase I Aircraft Approach Flyover PNL, Combined Components, Centerline Mike 74 Phase I Aircraft Approach Flyover PNL, Fan Inlet Component, 710 ft Sideline Mike 75 Phase I Aircraft Approach Flyover PNL, Fan Exhaust Component, 710 ft Sideline Mike Phase I Aircraft Approach Flyover PNL, Combined Jet 100 Component, 710 ft Sideline Mike vi Continued Tables and Figures - List of Number Page Title Number PNL, Turbine - Aircraft Approach Flyover 77 Phase I Mike Component, 710 ft Sideline Turbomachinery PNL, Compressor Aircraft Approach Flyover 78 Phase I Sideline Mike Inlet Component, 710 Flyover PNL, Combined I Aircraft Approach 79 Phase 710 ft Sideline Mike Components, Contours, Low I Aircraft 95 PNL Component 80 Phase Rise Take-off Contours, Short 95 PNL Component Phase I Aircraft Approach Descent Rise 106 Aircraft Cross Flow Effect Low 82 Phase I Flyover PNL Fan Inlet Component Take-off Effect Low Rise Phase I Aircraft Cross Flow Flyover PNL Fan Exhaust Component Take-off Cross Flow Effect Low Rise 84 Phase I Aircraft Flyover PNL Jet Exhaust Component Take-off Cross Flow Effect Low Rise 85 Phase I Aircraft PNL Components Flyover Take-off All PNL, 110 II Aircraft Component Comparison Flyover 86 Phase Suppression, No Nacelle Reference Case, Fan Exhaust Treatment Varying 111 II Aircraft Flyover PNL Comparison 87 Phase Fan Inlet Level on Lift Suppression vii I. SUMMARY As instructed in Task V of NASA Ames contract NAS2-5462 an analytical study of fly-over noise was carried out 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 as a function of noise footprint area.
The study was carried out in two phases. Engine component noise was held the same for both phases. The difference was that Phase I utilized a lift fan commercial transport aircraft operated along two different paths. Phase II used a lift-lift/cruise fan commercial transport aircraft and was restricted to only one path. The effect of cross-flow was considered for both inlet and exhaust sections of the engine.
Some significant conclusions were: 1. Fan exhaust radiated noise is the loudest noise contributor of the five components considered.
2. Total area within a contour is sensitive to the flight path and was minimized using the long vertical rise and descent.
3. Cross flow effects can increase component noise one to two PNdB.
4. Trade-off's available in flight speed, power plant exhaust vector angle, and aircraft flight trajectory can result in significant changes in noise contours.
II. INTRODUCTION has Electric Company Flight Propulsion Division Historically the General design studies, component tests, and manufacture of experimental carried out LF460 was carried propulsion units. A recent lift fan study designated lift fan transport. This work was out to support an application for a small intercity contract NAS2-5462.
performed for NASA Ames under In addition to the engine design effort noise characteristics were pre- dicted and an analysis carried out using these characteristics to predict fly- over noise with the lift fan installed in specific aircraft. This report presents a description and results of the fly-over noise study, PRECEDING PAGE LANB NOT FThMED III. CALCULATION TECHNIQUES produced by To identify the effects of significant engine noise sources operation of V/STOL aircraft during the take-off and landing configurations, a sophisticated calculation procedure was required to predict the individual noise sources and combine them in the correct sequence. Since large amounts of noise spectra are handled and many of the calculations of data in the form calculation procedures was necessary.
are repetitive, the use of computer computer programs were modified to suit the Consequently existing fly-over noise needs of this study.
a mathematical model to calculate the effect One revision was to prepare moving across the jet nozzle and per- of jet noise generation of a flow of air to be significant in the pendicular to its axis. This effect was considered was in some cases at an case of the V/STOL aircraft since the lift fan exhaust cross-flow. Cal- angle to the fuselage axis and thus subject to considerable calculation since culation of this effect was made as part of the fly-over noise was required. Typical a continuous evaluation of the aircraft forward motion in the form of delta dB are corrections are shown in Figure 1. The corrections velocity. The cross-flow a function of jet exhaust velocity and cross-flow method is presented in Reference 1.
calculation to the effect revision to the existing computer program, similar A second the lift on the exhaust jet noise, was to adjust for flow across of cross-wind took the form of an incremental change to the fan inlet. The adjustment fan fundamental as a function of fan tip speed and aircraft forward speed.
identifying this adjustment factor. A Test data was used as the basis of is shown in Figure 2. The details as to how this typical adjustment schedule presented in Reference 2.
adjustment schedule was generated are to the computer program was to increase the A third necessary revision routines. Due to the presence of capacity of the fly-over noise calculation sources such as lift fans, cruise fans, and gas generator, a several noise variety of different noise producing components are present. These components capability of varying their thrust axis with respect to the fuselage also have the or decreasing power on an individual basis.
centerline as well as increasing PRECEDING PAGn BT~A-r NT
P!r,.D
Consequently the computer program was expanded to accommodate the necessary variables. Computer subroutines used to calculate the noise contour coordinates were adapted for use with the expanded program.
Computer techniques for handling component noise prediction were generally available. However, some specialized options and methods of mechanically hand- ling large amounts of information were instituted for this study. Consequently the computer program was expanded to accommodate the necessary variables.
Computer subroutines used to calculate the noise contour coordinates were adapted for use with the expanded program.
Computer techniques for handling component noise prediction were generally available. However some specialized options and methods of mechanically han- dling large amounts of information were instituted for this study.
The noise contour coordinates were prepared using an interitative technique.
From a specific runway centerline position an initial approximation of the con- tour sideline coordinate was made using a sideline distance - EPNL schedule based on previous experience with noise contour calculations. Spreading out from this initial point, fly-over calculations were performed until sufficient calculations were made at listening (microphone) locations which bracketed the desired con- tours. The exact contour coordinate was then calculated by interpolating between the known points.
The fly-over noise calculation is made by placing the listening microphone at a specific location on the ground plane. The engine noise source mounted on the aircraft traverses a given trajectory such as the climb or approach path.
The noise is then predicted at the microphone at specific time intervals based on separation distance and angle orientation.
Noise is attenuated by a distance correction; the spherical divergence, an atmospheric correction factor, and an EGA factor applied over that portion of the separation distance that lies within a 100 foot boundary layer from the ground.
It was also assumed that the full volume of noise from all engines is heard by the ground microphone and that no noise reduction occurs from fuselage shielding.
IV. ENGINE COMPONENT NOISE the LF460 lift fan. A propulsion unit used for this study is The basic plant and is described study was carried out on this power comprehensive design aero- in Reference 3. The engine design study provided mechanical design, The noise analysis analysis, performance data, and a noise analysis.
thermal and characteristics, noise generating mechanisms described general noise to a lift The engine study was not limited suggestions for noise suppression.
also included analysis of the engine components configured fan configuration but lift at take-off.
with a swiveled nozzle for additional vertical as a cruise fan was the detailed analysis for the contour study it In order to carry out spectra for the various engine components. Five necessary to predict noise and are listed below: specific components were chosen 1. Fan inlet radiated noise.
2. Fan exhaust radiated noise noise 3. Compressor inlet radiated from the fan exhaust and tip turbine exhaust.
4. The combined jet noise 5. Tip turbine turbomachinery noise.
prediction techniques Existing General Electric, acoustic engineering noise spectrum using aero-thermodynamic were utilized to prepare the component data from the engine design study.
from the original It is noted that some size scaling was accomplished LF460 design. The designated aircraft take-off gross weight of the original This aircraft had four lift fans or Phase I research aircraft was 51,500 Ibs.
excess of thrust It was also assumed that for safe operation an installed.
at lift-off an of ten percent was required. Consequently, to weight In addition to the required engine thrust of 14,200 lbs. is needed.
individual and thrust a 20% increment is required for safety considerations lift-off to the "most out control. The noise rating point, however, was referred engine is or "working" lift-off thrust value of 14,200 lbs. and this value used" as 80 percent of maximum available thrust. The referenced to the lift fan ratio is based on the LF460 reference design scaled in the component noise then are = 1.165. Scaled engine thermodynamic cycle parameters of 14,200/12,200 presented as Table I.
Since the power plant components used in both the Phase I and Phase II sections of this contour study are from the same family of power plants the basic noise spectra are applicable for both phases of the study.
V. AIRCRAFT CHARACTERISTICS A. Lift Fan Aircraft The aircraft used in Phase I of this study was a vehicle representing the pure lift fan approach to commercial VTOL. The vehicle incorporates four lift fans with exit louvers and mounted in large pods on the wing with their respective gas generators.
A plan view of the aircraft is shown on Figure 3.
Figure 4 defines the thrust vector angle. Take-off gross weight for this Phase I aircraft was assigned as 51,500 pounds. The power plants were sized using the rule that 20% of the thrust must be reserved for emergency control purposes and a 10% excess of thrust over take-off gross weight is required at lift-off.
Consequently the nominal take-off operating power required is 80% of full power. This 80% power point was specifiedas the noise rating point and is therefore defined for purposes of our noise analysis as a power setting of unity.
To exercise the noise characteristics of the Phase I aircraft two flight paths were selected.
The first was a short vertical rise with a shallow climb and gradually increasing speed. The second was a long vertical rise, a horizontal sprint for rapid acceleration, and nominal climb out. Two compatible landing paths were also considered.
The first path utilized a short vertical descent and the second followed a long vertical descent. Each path had its own unique speed schedule, lift fan exhaust louver schedule, aircraft attitude schedule, and engine power setting schedule. These schedules are presented on Figures 5 through 24.
B. Lift-Cruise Fan Aircraft For Phase II of the study an aircraft with lift cruise fans installed as well as lift fans was chosen for examination. A general arrangement of the aircraft is shown on Figure 25. Four lift fans, two mounted on the wings and two mounted on the fuselage are installed. Two lift cruise fans are mounted on the aft fuselage location replacing the conventional power plants and are capable of supplementing vertical lift during the take-off and landing operation. The cruise fans have swivel nozzles with a fixed inlet oriented along the fuselage centerline. The cruise fan gas generators are mounted close to the cruise fans along the fuselage axis. Since the cruise power plant inlets have a horizontal orientation it was assumed no distortion occurred due to crossflow.
The lift fans are mounted so that the inlet is oriented perpen- dicular to the fuselage centerline. The lift fan exhaust is directed through a set of louvers. The lift fan gas generators are mounted such that their inlets are somewhat shielded from the ground. Consequently, the assumption was made that they do not contribute to the overall noise. A detail schedule of engine component operations is presented on Table II.
The aircraft flight path characteristics are presented on Figures 26 through 35. Both take-off and approach have a 500 foot vertical trajectory at the brake release and touch-down point with a gradually increasing climb or descent from the 500 foot altitude point.
The engines used on the second aircraft in Phase II of the study are assumed to be the same family used on the Phase I aircraft so that no new noise spectra calculations were required. Since the Phase II aircraft is assisted in vertical thrust with two swivel nozzle cruise engines it was assumed that the take-off gross weight was 42 percent greater than the Phase I aircraft.
VI. AIRCRAFT NOISE CONTOURS A. Phase I Aircraft In Phase I of the study, calculations were performed for two path tra- jectories with corresponding schedules for changes of aircraft and engine characteristics.
The primary difference in the paths was the length of the vertical rise or descent. These differences produced the most significant changes when comparing the noise contours calculated from the two paths. Both PNL and EPNL contours have been prepared and the take-off plots are shown on Figures 36 through 39. Both the PNL and EPNL contours show similar characteristics.
When the aircraft is flown along the path with the high vertical rise more area is enclosed for a given noise level in the vicinity of the brake release point than for the flight with the short vertical rise. As the aircraft continues along the flight path the noise contours move out and uncover additional noise area for both the high rise and low rise trajectories.
Continuing to monitor the noise effect as the aircraft continues its flight, the contours resulting from the high rise path start to close early.
For example, the 95 and 100 PNL take-off contours show a sideline distance reduction starting at the 2000 foot mark due primarily to power reduction and the increased separation distance from the ground.
The low rise path in contrast shows steadily increasing contour coordinates from the combined effects of the aircraft rising out of the attenuation from ground effect, rear angles of the component noise spectra are uncovered, and the added increment from cross-flow effect due to increased velocity. For this low rise path, the contour shows a rapid closing trend when power cutback is initiated and the climb path steepens. The net result is considerably more area enclosed by the low rise path in contrast to the high rise path for a given PNL or EPNL value. A second significant conclusion is that the maximum sideline value of the noise contour is about the same for either path. However this maximum point occurs at different locations along the projected flight track.
To highlight the comparison of contour area calculated for the low rise and high rise take-off paths figure 40 presents the 95 PNL contours replotted on the same graph. The graph visually confirms the previous discussion.
The approach contours are presented on figures 41 through 44. Corresponding to the high and low vertical rise take-off paths two approach paths were examined considering a high and low vertical descent. The noise contours show that with the shorter separation distances experienced during the low vertical descent path the contours are elongated in shape and cover considerably more area than the contours resulting from the high vertical descent.
Figure 45 presents a comparison of the 95 EPNL contours replotted on the same graph. This comparison dramatically shows the concentrated noise pattern for the long descent path.
B. Phase II Aircraft Due to the many variables in the noise generation the location in three- dimensional space of the aircraft or noise source is important when a specific noise is generated that determines an important contour location.
Figure 46 qualitatively shows these aircraft space locations and is presented as a ref- erence in the following contour discussion.
Figure 47 presents the take-off PNL contour for three PNL values. The maximum sideline distance for the 95 PNL contour is 1330 feet and is deter- mined while the aircraft is at the top of the vertical ascent made with the engines at maximum VTOL allowable power. The controlling noise component is from the wing lift fan exhaust radiated noise which presents an acoustic angle of 111 degrees. Note that the aircraft has reached an altitude where the acoustic angle for maximum PNL has been exposed. This effect coupled with increased speed produces the maximum noise value. Further travel along the flight track increases the range and attenuates the noise for a reduction in PNL.
The 95 PNL closure point occurs at a point 2100 feet down the runway. The controlling noise component is still the fan exhaust radiated noise component.
As the aircraft moves along the flight track, the path parameters have stabilized and the controlling factor is range which is steadily increasing with resulting contour closure.
Figure 48 presents the approach contour for three PNL valves. In the approach operation, the lift fan exhaust noise component has the largest single value and thus the greatest effect on overall noise. The maximum sideline value of the 95 PNL contour occurs at 1240 feet. The aircraft is still about 250 feet from the vertical descent point with the engines at a power setting less than 0.7.
the noise occurring when of maximum sideline The apparent inconsistency than other aircraft-micro- and power setting less distance is larger separation adjustment factors.
the cross flow is explained by examining phone combinations speed is reduced and descent point, the the vertical As the aircraft approaches allowing a PNL reduction.
on noise also reduces the effect of cross-flow feet outbound from the occurs at a point 3250 The PNL closure point represents and the closure parameters have stabilized point. All path touchdown the effect of increasing range.
II Comparison C. Phase I and Phase for the Phase I and of the contour area 49 presents a comparison Figure full lines show the com- the basis of PNL. The take-off operation on Phase II gross weights.
basis using aircraft with different parison on the as calculated adjusted so with the noise values an approximation The dotted line presents I aircraft.
weight as the Phase has the same gross that the Phase II aircraft results is the adjusted Phase II Phase I results and The difference between in the Secondary differences in flight paths.
due to the difference primarily in speed, vector angles, and engine contours can be traced to variations noise air- available in VTOL show that the parameters combinations which component signature.
used to influence the noise craft operation may be approach operation. In similar comparison for the Figure 50 presents a and the adjusted Phase very little difference case the flight paths show this except for the lower noise with the Phase I schedule of area is coincident II values.
VII, NOISE COMPONENT ANALYSIS result of inter- coordinate is the contour The location of a particular as spectra directivity, range, a number of parameters such action between power setting, and airplane attitude, schedule, velocity, altitude, vector Consequently, description noise components.
relative strength of the individual analysis. The following location is a complex of the noise at a particular the parameters.
the interaction of to help understand discussion is presented components. These five distinct was separated into total engine noise The combined oriented fan noise, noise, exhaust inlet oriented fan components are the core and cooler fan exhaust, exhaust hot fan tip turbine noise from the jet the tip turbine turbomachinery compressor noise, and engine inlet radiated noise.
the basic components form for these five static spectra The predicted directiv- In particular the fly-over noise.
used to calculate building blocks is component of the individual the acoustic angle interest since ity is of noise component static noise. The at the total to vary in arriving allowed 55.
on Figures 51 through for reference is presented we examined on fly-over noise of the components the impact To understand In this case calculations Phase I study.
results from the detail the fly-over in as PNL was chosen for comparison.
aircraft paths for two separate were made during fly-over of PNL was then examined The variation measure.
a fundamental rise paths.
and high vertical vertical rise from the low the effects comparing source passes a fixed as the noise the PNL variations decided to examine It was centerline was on the runway first point chosen. The Two points were point.
this data.
56 through 79 present Figures second was on a sideline.
and the location produce microphone data received at centerline Calculations from location the at the sideline PNL values whereas changes in the rather rapid of is really an expression This phenomenon change more gradually.
functions from different viewed velocity is of change with where the rate the geometry the path.
the side or along exhibited by of the fly-over PNL curves The difference in the behavior provide an additional low rise paths the high rise and the results from comparing PRECEDING PAG- BLANiK NOT FILMED measure of evaluating the fly-over noise. The PNL values from the short vertical rise path show larger absolute values than the values from the high rise path. Also in general the PNL curves representing the low rise path have steeper slopes. The significance of these changes is seen when they are related to EPNL which is a function of peak PNL and duration.
Thus we have a mechanism to significantly effect fly-over noise from an EPNL standpoint.
Based on absolute value considerations the noise from various engine components do not add directly but are affected by operational considerations of individual vectoring and power setting as well as the logarithmic addition rule. Nevertheless the relative strengths of the various engine components can be seen from Figures 80 and 81 which presents the PNL contours as if a single component had independently traversed the fly-over pattern.
The effect of the cross-flow operational factor is to increase the fan inlet radiated noise and the jet noise.
To evaluate the cross-flow effect we choose a point 7000 feet down the take-off track which was far enough from the brake release position so the forward speed of the aircraft has created a strong cross-wind component.
To illustrate the effect on the PNL values data is presented on Figures 82 through 85 showing the total effect and the effect on the individual components of PNL fly-over with an without cross-flow effect.
Despite the fact that two different mechanisms caused a change in the jet noise, i.e., inlet distortion and jet plume deflection, the change in PNL was about the same for both inlet or jet. The assumption was made that cross-flow does not effect the core compressor or turbine noise components.
Consequently only fan and exhaust components are plotted.
The total cross-flow effect at this particular runway location and specific operational time frame is one to two PNdB.
VIII. EFFECT OF SUPPRESSION EXTERNAL TO THE ENGINE The lift and lift cruise fan noise levels used to calculate the contours in Section V accounted for the application of acoustic wall treatment presented and splitters in the fan exhaust. In an actual aircraft installation there is the potential of increasing suppression by adding wall treatment and splitters to the wing and fuselage nacelles which contain the basic fan. Figure 86 shows the noise constituents of the basic fan with exhaust treatment. The following sources are dominant: (1) Cruise fan exhaust (2) Lift fan exhaust (3) Cruise fan inlet (4) Gas generator inlet (5) Lift fan inlet Sources 1 through 4 may be further suppressed by treatment of the nacelle performance loss but little or no change with attendent penalties in weight and length. Source 5, lift fan in the lift fan nacelle depth or cruise fan nacelle the shallow inlet associated with the lift inlet is not easily suppressed due to define suitable inlet treatment arrangements have shown fan design. Studies to to be quite severe even for small suppression levels the installation penalties the limiting noise level if sources 1 through like 3 PNdB. Source 5 thus becomes 4 are decreased substantially.
additional treatment to the wing and To establish the benefit of adding levels were assumed for sources fuselage nacelles, the following suppression 1 through 4.
APNdB -15 (1) Cruise fan exhaust -15 (2) Lift fan exhaust -10 (3) Cruise fan inlet -10 (4) Gas generator inlet was then assumed to vary in suppression from 0 The lift fan inlet noise to 20 PNdB and the total system noise calculated.
Figure 87 shows the results of the suppression study. With the suppression defined above and no lift fan inlet suppression a 500 foot sideline level of 100.5 PNdB may be obtained. This is a reduction of approximately 7 PNdB. With lift minimum of the total system noise may be reduced to a fan inlet suppression noise less With 2 to 3 PNdB inlet reduction a total system approximately 98 PNdB.
As seen by the above results the benefits of than 100 PNdB can be obtained.
due to both the lift fan inlet noise additional suppression are severely limited adding 10 to 15 PNdB suppression and the jet noise floor shown on Figure 82. By was obtained and with 1 through 4 only 7 PNdB system noise reduction for source of up to 20 dB inlet reduction a maximum of 9 PNdB total system the addition is obtained.
noise reduction IX. CONCLUSIONS 1. Considering the complete aircraft system and based on the noise suppression technology level assumed in the initial engine design the exhaust radiated fan noise is the loudest single noise contributor identified in this study. Projecting our suppression technology at some future time period the exhaust radiated fan noise and other components could be suppressed a sufficient amount so that the critical component would be forward radiated fan noise. Suppression of this component in turn is restricted by available space and mechanical design considerations.
It is noted that the core compressor inlet and the forward radiated fan components produce higher PNL values than the rear radiated fan noise when considering individual static spectrum. However, power plant installation characteristics result in shielding the critical acoustic angles for these two components.
2. The phase II aircraft is quieter because a better take-off profile increases the separation distance from the source to the microphone.
3. Using enclosed area within a specific noise contour as a criteria this area is reduced by using a long vertical raise or descent path as contrasted to the larger enclosed contour area resulting from the short vertical rise or descent type of path.
4. The maximum sideline distance or width of any particular contour is the same for either the long vertical rise or short vertical rise.
However, the maximum width occurs at different points along the extended runway centerline.
5. Reductions in engine power settings as well as attained altitude provide the most significant effects on shaping the closing point of the noise contour.
6. The objective of achieving a PNL noise level less than 100 PNdB on a 500 ft sideline can be achieved for the aircraft used in this study and using a suppression schedule within our predicted future tech- nology. The critical suppression is a 5 PNdB reduction for the fan inlet oriented noise component.
7.
Cross-flow effects are primarily influenced by aircraft forward velocity and consequently are more significant at listening or microphone locations farther along the runway. For example, for the short vertical rise path at 7000 feet down the runway centerline the cross-flow can be as much as a one to two increase in PNL.
X. NOMENCLATURE TERM DESCRIPTION UNITS EGA Extra Ground Attenuation AdB EPNL Effective Perceived Noise Level dB EPNdB dB Decibel; re: .0002 dynes/cm M/S Meters per Second PNL Perceived Noise Level dB PNdB P.S.
Power Setting SPL Sound Pressure Level dB TOGW Take-Off Gross Weight Lbs.
V Velocity Ft/Sec M/Sec V/STOL Vertical or Short Take-Off and Landing VTOL Vertical Take-Off and Landing XI. List of References 1. TM 72-315 "Effect of VTOL Aircraft Flight Speed on Lift Fan Jet Noise Generation".
2. TM 72-151 "Effect of VTOL Aircraft Flight Speed on Lift Fan Noise Generation".
3. NASA CR-120787 "LF460 Detail Design".
TABLE I Engine Cycle Parameters Scaled LF460 Fan Power Setting V V28 W W28 8 VTip 1.000 675 680 80.5 658 1048 .909 620 650 77.5 635 1004 .882 595 640 76 623 992 .854 585 630 75.5 611 975 .817 565 620 74 600 964 .791 550 605 73 589 .745 525 585 70.5 565 .682 500 560 67.5 541 875 .591 520 63.5 501 818 .499 430 475 60.5 466 758 .409 380 420 56 419 688 .273 300 360 49 362 583 A = 4.35 A28 = 12.88 TABLE II Noise Component Designations NASA AMES Contour Study Phase-II Advanced VTOL Type Study Aircraft Cross Source Source Vector Flow Designator Source Description Number Schedule Correction Cruise Fan Inlet 2 Fixed at No 0=0 Cruise Fan Exhaust 2 Variable = Cruise No Cruise Fan Jet 2 Variable Yes = Cruise Cruise Engine Turbine Variable No Noise = Cruise 5 Gas Generator Fixed at No = Lift Engine Fan Inlet Fixed at Yes = 900 Lift Engine Fan Exhaust 4 Variable Yes S= Lif Lift Engine Jet 4 Variable Yes = Lift Lift Engine Turbine Noise 4 Variable No = Lift VCROSs FLOW/VJT .
3 O
SVOcRoss FL w/VJET - .2 -
.i I iI i I I I i t i I I ' I
1 10 100 STROUHAL NUMBER FIGURE 1 TYPICAL CROSS FLOW CORRECTIONS - EXHAUST C.i o I .1 .2 INLET CROSS FLOW VWLOCITY/ FAN TIP VELOCITY FIGURE 2 TYPICAL CROSS FLOW CORRECTIONS - INLET 3 PLAN VIEW - PHASE I AIRCRAFT FIGURE FIGURE 4 PHASE I AIRCRAFT THRUST VECTOR ANGULAR REFERENCE - 2000 400- PA 1000 200- 12500 15000 FEET 0 2500 5000 7500 10000 0 1000 2000 3000 4000 5000 METERS RUNWAY CENTERLINE DISTANCE FIGURE 5 PHASE I AIRCRAFT LOW RISE TAKEOFF PATH 600- -1500 2500 5000 7500 10000 12500 15000 FEET I , I I 0 - I I I iI 0 1000 2000 3000 4000 5000 METERS RUNWAY CENTERLINE DISTANCE FIGURE 6 PHASE I AIRCRAFT HIGH RISE TAKEOFF PATH 120-_ - - 40 60- 40- 20- -o
15000 17500 FEET
7500 10000 12500
2500 5000
METERS 2000 3000 RUNWAY CENTERLINE DISTANCE VELOCITY LOW RISE TAKEOFF PHASE I AIRCRAFT FIGURE 7 120 - -60 100 -50 -
-- 30
S40 - 20 -10 2500 5000 7500 10000 12500 15000 17500 FMa I I lI I 0 1000 2000 3000 4000 5000 METERS RUNWAY CENTERLINE DISTANCE FIGURE 8 PHASE I AIRCRAFT HIGH RISE TAKECFF VELOCITY 1.O - .8 .6 - p4 .2 9000 11000 13000 15000 17000 FEET 1000 3000 5000 7000 I I I I 1 I 0 1
3000 4000 5000 MTIERS
8 1000 2000
RUNWAY CENTERLINE DISTANCE AIRCRAFT LOW RISE TAKEOFF POWER SETTING FIGURE 9 PHASE I 1.0 .8 o .6
5 .4
.2 1000 3000 5000 7000 9000 11000 13000 15000 17000 FEET I I I I I I I 0 1 2000 3000 4000 5000 METERS 0 1000 RUNWAY CENTERLINE DISTANCE FIGURE 10 PHASE I AIRCRAFT HIGH RISE TAKEOFF POWER SETTING 1000 3000 9000 11000 13000 15000 17000 FEET I I I I I I I 5000 METERS RUNWAY CENTERLINE DISTANCE FIGURE 11 PHASE I AIRCRAFT LOW RISE TAKEOFF LOUVER SCHEDULE 30 -
20 -
S10 -
1000 3000 5000 7000 9000 11000 13000 15000 17000 FEET 0 . I I I I I I I I I j 0 1000 3000 4000 METERS RUNWAY CENTERLINE DISTANCE FIGURE 12 PHASE I AIRCRAFT HIGH RISE TAKEOFF LOUVER SCHEDULE 1000 3000 5000 7000 9000 11000 13000 15000 17000 19000 FEET -4 I I I I I I 1 I I I I I I O 1000 2000 3000 4000 METERS RUNWAY CENTERLINE DISTANCE FIGURE 13 PHASE I AIRCRAFT LOW RISE TAKEOFF ATTITUDE SCHEDULE looo1000 3000 5000 7000 9000 11000 13000 15000 17000 FEET I I I I I I I -4 1 I I 0 1000 2000 3000 4000 5000 METERS RUNWAY CENTERLINE DISTANCE FIGURE 14 PHASE I AIRCRAFT HIGH RISE TAKEOFF AT'TITUDE SCHEDULE 300- 300- -800 200- -400 100- -200 -3500 -3000 -2500 -2000 -1500 -1000 -500 FEET o 1 1 I I I I I I I I -1000 -800 -600 -400 -200 0 METERS RUNWAY CENTERLINE DISTANCE FIGURE 15 PHASE I AIRCRAFT LOW DESCENT APPROACH PATH -1400 400- - -800 S200- - - 600 -400 100- FEET -1500 -1000 -500 -2500 -2000 -3000 0 I I I I I - -400 -200 0 METERS -1000 -800 -600 RUNWAY CENTERLINE DISTANCE 16 PHASE I AIRCRAFT HIGH DESCENT APPROACH PATH FIGURE 4r 120 -60 100 -50 80 0 -- -- - 10 -3500 -3000 -2500 -2000 -1500 -1000 -500 FEET 0i I I I 1 i -1000 -800 -600 -400 -200 0 METERS RUNWAY CENTERLINE DISTANCE FIGURE 17 PHASE I AIRCRAFT LOW DESCENT APPROACH VELOCITY 120 - 60 100 -50 80 -_ 40
I 60
-30 - - 20 20- 10 -3500 -3000 -2500 -2000 -1500 -1000 -500 FEET I I I I 0 1 -1000 -800 -600 -400 -200 0 METERS RUNWAY CENTERLINE DISTANCE FIGURE 18 PHASE I AIRCRAFT HIGH DESCENT APPROACH VELOCITY -10 i -10 -3000 -2500 -2000 -1500 -1000 -500 0 FEW -20 I I I I -800 -600 -400 -200 0 METERS RUNWAY CENTERLINE DISTANCE FIGURE 19 PHASE I AIRCRAFT LOW DESCENT APPROACH LOUVER SCHEDULE O- -10 -3000 -2500 -2000 -1500 -1000 -500 0 FEET -20 I I I I I I -800 -60 -400 -200 0 METERS RUNWAY CENTERLINE DISTANCE FIGURE 20 PHASE I AIRCRAFT HIGH DESCENT APPROACH LOUVER SCHEDULE .2 -500 0 FEET -2500 -2000 -1500 -l000 -400 -200 0 METERS -800 -600 RUNWAY CENTERLINE DISTANCE APPROACH POWER SETTING 21 PHASE I AIRCRAFT LOW DESCENT FIGURE 1.0- .8 .6 .2 -1000 -500 0 FEET -2500 -2000 -1500 -800 -600 -400 -200 0 ML TIRS RUNWAY CENTERINE DISTANCE FIGURE 22 PHASE I AIRCRAFT HIGH DESCENT APPROACH POWER SETTING S-4 -8 0 FEET -1500 -1000 -500 -3000 -2500 -2000 I I , I I 0 METERS -800 -600 -400 -200 RUNWAY CENTERINE DISTANCE FIGURE 23 PHASE I AIRCRAFT LOW DESCENT APPROACH ATTITUDE SCHEDULE -4- -8 -3000 -2500 -2000 -1500 -1000 -500 0 FEET I I I I -1000 -800 -600 -400 -200 0 METERS RUNWAY CENTERLINE DISTANCE FIGURE 24 PHASE I AIRCRAFT HIGH DESCENT APPROACH ATTITUDE SCHEDULE V ev CR FAV FIGURE 25 PHASE II AIRCRAFT PLAN VIEW AND THRUST VECTOR ANGULAR REFERENCE _1200 300- 200- -o 100- 2500 3000 3500 FEET 500 1000 1500 2000 I I I I I I 0 I 800 1000 METERS 0 200 400 600 RUNWAY CENTERLINE DISTANCE FIGURE 26 PHASE II AIRCRAFT TAKEOFF PATH -600 200- S600 100- -200 PET -1000 -500 -1500 -2000 -2500 -3000 -3500 I I I I I I 0 METERS -200 -400 -600 -800 -1000 DISTANCE RUNWAY CENTERIZNE APPROACH PATH 27 PHASE II AIRCRAFT FIGURE
-70
- 60 oo- 8o - 60 30 40 - 20 - 10 500 1000 1500 2000 2500 3000 ZER I I I I 400 600 800 1000 MmERS RUNWAY CENTERLINE DISTANCE FIGURE 28 PHASE II AIRCRAFT TAKEOFF VELOCITY S70 120 - _ 6 1oo - 50 80--40
-30
- -- 10 -3000 -2500 -2000 -1500 -1000 -500 FKET
I
I
I
I I
o " 1
-1000 -800 -600 -400 -200 0 METERS RUNWAY CENTERLINE DISTANCE FIGURE 29 PHASE II AIRCRAFT APPROACH VELOCITY 1.0 .8 .2 500 1000 1500 2000 2500 3000 FEET I I I i I i 0 200 400 600 800 1000 METERS RUNWAY CENTERLINE DISTANCE FIGURE 30 PHASE II AIRCRAFT TAKEOFF POWER SETTING 1.0 .8 S .6 .2 -3000 -2500 -2000 -15oo -1000 -500 0 FnT I I I I -800 -600 -400 -200 0 METERS RUNWAY CENERLINE DISTANCE FIGURE 31 PHASE II AIRCRAFT APPROACH POWER SETTING CAJ 24 - 500 1000 1500 2000 2500 3000 FEET 0 I I I I I I I I 200 400 600 800 1000 METERS RUNWAY CENTERLINE DISTANCE FIGURE 32 PHASE II AIRCRAFT TAKEOFF ATTITUDE SCHEDULE -4 -500 0 FEET -3000 -2500 -2000 -1500 -1000 -800 -600 -4 0 -200 0 METERS RUNWAY CERTERLINE DISTANCE PHASE II AIRCRAFT APPROACH ATTITUDE SCHEDULE FIGURE 33 -. 4 100 - bV 60 60 0 - E4 20 - CR (LInFT/CRUISE FA) 1500 2000 2500 FEW -20 I I I M ERS RUNWAY CTEIRLINE DISTANCE
FIGURE 34
PHASE II AIRCRAFT TAKEOFF THRUST VECTOR SCHEDULES 120 - 100 - (LIFT/CRUISE FAN) CR
80 -
-
v
(LIFT
FAN)
-20 -2500 -2000 -1500 -1000 -500 FET -40I -800 -600 -400 -200 0 MTERS RUNWAY CENTERLNNE DISTANCE FIGURE 35 PHASE II AIRCRAFT APPROACH THRUST VECTOR SCHEDULES AREA ENCLOSED BY CONTOUR 95 PNd 480 ACRES 100 PNd 255 ACRES 105 PNdB 120 ACRES - - o
105 dB
95 dB - 500- m - 2000 -2000 0 2000 4000 6000 8000 10000 12000 Ea1r I I I I I I I II I I -500 0 500 100ooo 1500 2000 2500 3000 3500 METERS RUNWAY CENTERLINE DISTANCE FIGURE 36 PHASE I AIRCRAFT LOW RISE TAKE-OFF PNL CONTOUR AREA ENCLOSED BY CONTOUR 95 P1dB 315 ACRES 100 PNdB 125 ACRES 105 PMidB 37 ACRES -000
d100
dB 105 dB 500 - mt -2000 -200 2000 4000" 8000 10000 12000 FEET -500 0 500 1000 1500 2000 2500 3000 3500 MITERS RUNWAY CENTERLINE DISTANCE FIGURE 37 PHASE I AIRCRAFT HIGH RISE TAKE-OFF PNL CONTOUR CONTOUR AREA ENCLOSED BY 95 EPNdB 670 ACRES 420 ACRES 100 EPNdB 105 EPNdB 225 ACRES .2000 E-4 105 dB 100 dB 95 dB 0 - 0 500 - U 2000 4000 6000 8000 10000 12000 FEET -2000 0 2000 1aoo00 1500 2000 25'00 3600 3500 METERS -500 0 500 RUNWAY CENTERLINE DISTANCE CONTOUR FIGURE 38 PHASE I AIRCRAFT LOW RISE TAKEOFF EPNL AREA ENCLOSED BY CONTOUR 95 EPNdB 515 ACRES 100 EPNdB 295 ACRES 105 EPNdB 145 ACRES -2000 500- 100 d 95 d 0- -0 105 dB 500- -2000 0 2000 4000 6000 8000 10000 12000 FEET I I I I I 1 1 -500 0 5 9 1000 1500 2000 2500 -3000 3500 METERS RUNWAY CENTERLINE DISTANCE FIGURE 39 PHASE I AIRCRAFT HIGH RISE TAKEOFF EPNL CONTOUR AREA, ACRES LOW RISE TAKEOFF 480 HIGH RISE TAKEOFF 4000- 1- 000 2000- - 0-- 0 H- 2000- 1000 -2000 4000 6000 10000 12000 FEET 4000 I I I I I I I -1000 -500 0 500 1000 1500 2000 2500 3000 3500 METERS RUNWAY CENTERLINE DISTANCE FIGURE 40 PHASE I AIRCRAFT TAKEOFF PNL CONTOUR COMPARISON BY CONTOUR AREA ENCLOSED 280 ACRES 95 PNdB E 100 PNdB 140 ACRES PNdB 61 ACRES -2000 500- -1000 250- dB 105 dB 95 dB 100 0--) -1000 -2000 1000 2000 FEET -3000 -2000 -1000 0 -6000 -5000 -4000 I I I 0 500 METERS -1000 -500 -2000 -1500 RUNWAY CENTERLINE DISTANCE LOW DESCENT APPROACH PNL CONTOUR FIGURE 41 PHASE I AIRCRAFT AREA ENCLOSED BY CONTOUR
95 PNdB 120 ACRES
100 PNdB 42 ACRES 105 PNdB 18 ACRES - 2000 -1000 95 dB 105 dB
o -- 0
100 dB 0 - 1000 500 - - 2000 -5000 -4000 -3000 -2000 -1000 0 1000 2000 FEET
I I I I
-1500 -1000 -500 o 500 MWERS RUNWAY CENTERLINE DISTANCE FIGURE 42 PHASE I AIRCRAFT HIGH DESCENT APPROACH PNL CONTOUR AREA ENCLOSED BY CONTOUR 95 EPNdB 300 ACRES 100 EPNdB 140 ACRES E- 105 EPNdB 48 ACRES 500- -1000 105 dB 100 dB 95 dB 0 -- o J250 500 - -2000 -7000 -60p00 -5090 -4900 -3q00 -2000 -10p0 0 1000 FEET -1000 -500 0 METERS -2000 -1500 RUNWAY CENTERLINE DISTANCE I AIRCRAFT LOW DESCENT APPROACH EPNL CONTOUR FIGURE 43 PHASE AREA ENCLOSED BY CONTOUR 95 EPNdB 200 ACRES EPNdB 120 ACRES 105 EPNdB 63 ACRES -2000 -1000 0 -0 95 dB 100 dB 105 dB -1000 -5000 -4000 -3000 -2000 -1000 0 1000 2000 FEET I I I I I I I -1500 -1000 -500 0 500 METERS RUNWAY CENTERLINE DISTANCE FIGURE 44 PHASE I AIRCRAFT HIGH DESCENT APPROACH EPNL CONTOUR AREA, ACRES LOW DESCENT APPROACH 280 DESCENT APPROACH - HIGH - 500 1000- -
/
o-- o 1000- -- - 500 2000- -6000 -5000 -4000 -3000 -2000 -1000 0 1000 2000 FEET I I I I I I I I I I -2000 -1750 -1500 -1250 -1000 -750 -500 -250 0 250 500 METERS RUNWAY CENTERLINE DISTANCE FIGURE 45 - PHASE I AIRCRAFT APPROACH 95 PNL CONTOUR COMPARISON PROACH C LINE GROUND I LINE GROUND 95 PNL PNL 100 PNL 105 PNL 105 100 PNL 95 PNL PATH FIGURE 46 PHASE II AIRCRAT GENERALIZED SOURCE LOCATION ON AIRCRAFT BY CONTOUR w AREA ENCLOSED S95 PNdB 155 ACRES -1500 100 PNdB 70 ACRES 105 PNdB 29 ACRES 400- -1000 200" -500 100- 100- -500 200- 300-"1000 400- 1500 2000 2500 FEET -500 0 500 1000 -1500 -1000 400 500 600 700 METERS -200 -100 0 100 200 300 -400 -300 RUNWAY CENTERLINE DISTANCE FIGURE 47 PHASE II AIRCRAFT TAKEOFF PNL CONTOUR AREA ENCLOSED BY CONTOUR 180 ACRES 95 PNdB 100 PNdB 64 ACRES 400 105 PNdB 25 ACRES -1000 300- 95 dB 200- 100- dB.
- o
105 dB -500 300- -1000 -3000 -2500 -2000 -1500 -1000 -500 0 500 1000 1500 FEET I I I -1000 -800 -600 -400 -200 0 2 200 - 400 METERS RUNWAY CENTERINE DISTANCE FIGURE 48 PHASE II AIRCRAFT APPROACH PNL CONTOUR PHASE II ADJUSTED TO 51,500 LBS. TOGW 110 - PHASE II AT 73,200 LBS. TOGW PHASE I AT 51,500 LBS. TOGW 100 - IN I I I I I I I I I , , . . .I I 20 30 40 50 60 80 100 200 300 400 500 AREA, ACRES FIGURE 49 PNL CONTOUR AREA - TAKE-OFF OPERATION - COMPARISON PHASE I HIGH RISE AND PHASE II 110 - PHASE I AT 51,500 LBS. TOGW S-PHASE II AT 73,200 LBS. TOGW LBS. TOGW I I I I I I I I I . .
. .. i I I I 20 30 40 50 60 80 too 200 300 400 500 AREA, ACRES FIGURE 50 PNL CONTOUR AREA - APPROACH OPERATION - COMPARISON PHASE I HIGH DESCENT AND PHASE II
P.S. - 0.9
I I I I
30 50 70 90 110
130 150 170
ANGLE FROM INLET, DEGREES FIGURE 51 PHASE I AIRCRAFT COMPONENT NOISE - FAN INLET 110- P.S. 0.
k 90 I I I 70 I I 10 30 50 70 90 110 130 150 170 ANGLE FROM INLET, DEGREES FIGURE 52 PHASE I AIRCRAFT COMPONENT NOISE - FAN EXHAUST 120 - P.S 0.9 80- 130 150 90 110 50 70 10 30 ANGLE FROM INLET, DEGREES EXHAUST NOISE - JET AIRCRAFT COMPONENT 53 PHASE I FIGURE
P.S. = 0.9
70 I I I I I I 10 30 50 70 90 110 130 150 170 ANGLE FROM INLET, DEGREES FIGURE 54 PHASE I AIRCRAFT COMPONENT NOISE - CORE TIRBINE P.S.
- 0.9 70 I I I I ANGLE FROM INLET, DEGREES FIGURE 55 PHASE I AIRCRAFT COMPONENT NOISE - CORE COMPRESSOR - -t HIGH RISE PATH PATH RISE
O LOW
100- 90 -
80 -I I
80 90 100 110 120 130
SECONDS
TIME, 56 PHASE I AIRCRAFT TAKE-OFF FLYOVER PNL, FAN INLET COMPONENT, CENTERLINE MIKE FIGURE HIGH RISE PATH - - -j PATH O UW RISE 100-
go-
I
I I
80 90 100 110 120 130 TIME, SECONDS FIGURE 57 PHASE I AIRCRAFT TAKE-OFF FLYOVER PNL, FAN EXHAUST COMPONENT, CENTERLINE MIKE - - - HIGH RISE PATH PATH 0 LOW RISE *90 /
80 -
70 I I 80 90 100 110 120 130 TIME, SECONDS FIGURE 58 PHASE I AIRCRAFT TAKE-OFF FLYOVER PNL, COMBINED JET COMPONENT, CENTERLINE MIKE - - - HIGH RISE PATH 0 LOW RISE PATH
90 -
80 - 6o - 50 I I I TIME, SECONDS FIGURE 59 PHASE I AIRCRAFT TAKE-OFF FLYOVER PNL, TURBINE-TURBOMACHINERY COMPONENT, CE~fERLINE MIKE - - -A HIGH RISE PATH LOW RISE PATH O
90 -
I I I I I 80 90 100 110 120 130 SECONDS TIME, COMPONENT, CENTERLINE MIKE FIGURE 60 PHASE I AIRCRAFT TAKE-OFF FLYOVER PNL, COMPRESSOR INLET - - -A HIGH RISE PATH O LOW RISE PATH 1. 200 90 - - I I I 80 8o I I 80 90 100 110 120 130 TIME, SECONDS FIGURE 61 PHASE I AIRCRAFT TAKE-OFF FLYOVER PNL, COMBINED COMPONENTS, CENTERLINE MIKE - - - HIGH RISE PATH PATH O LOW RISE 100 - ,4 90 80 - I I 90 100 120 130 TIME, SECONDS FIGURE 62 PHASE I AIRCRAFT TAKE-OFF FLYOVER PNL, FAN INLET COMPONENT, 740 FT. SIDELINE MIKE - - HIGH RISE PATH PATH O LOW RISE 100- 890 - I 70 I 80 90 100 110 120 130 TIME, SECONDS FIGURE 63 PHASE I AIRCRAFT TAKE-OFF FLYOVER PNL, FAN EXHAUST COMPONENT, 740 FT. SIDELINE MIKE -1 - - -A HIGH RISE PATH RISE PATH O LOW 90- 80 _ I I 80 90 110 120 SECONDS TIME, FIGURE 64 PHASE I AIRCRAFT TAKE-OFF FLYOVER PNL, COMBINED JET COMPONENT, 740 FT. SIDELINE MIKE HIGH RISE PATH - - -A PATH LOW RISE O I I I I I 90 100 110 120 130 TIME, SECONDS COMPONENT, 740 FT. SIDELINE MIKE 65 PHASE I AIRCRAFT TAKE-OFF FLYOVER PNL, TURBINE-TURBOMACHINERY FIGURE - - -, HIGH RISE PATH O LOW RISE PATH 60 I I I I I 80 90 100 110 120 SECONDS TIME, PNL, COMPRESSOR INLET COMPONENT, 740 FT. SIDELINE MIKE FIGURE 66 PHASE I AIRCRAFT TAKE-OFF FLYOVER
- - - 8HIGH RISE PATH
O LOW RISE PATH 120 - 80 I I 80 90 110 120 TIME, SECONDS FIGURE 67 PHASE I AIRCRAFT TAKE-OFF FLYOVER PNL, COMBINED COMPONENTS, 740 FT. SIDELINE MIKE - - -6~HIGH DESCENT PATH PATH 0 LOW DESCENT 90o s- - - - I I I I I 40 50 60 70 80 TIME, SECONDS FIGURE 68 PHASE I AIRCRAFT APPROACH FLYOVER PNL, FAN INLET COMPONENT, CENTERLINE MIKE - - -A HIGH DESCENT PATH O LOW DESCENT PATH 110 -
-A--A--A
10A- AAA
90 - I 70I 50 60 70 80 TIME, SECONDS FIGURE 69 PHASE I AIRCRAFT APPROACH FLYOVER PNL, FAN EXHAUST COMPONENT, CENTERLINE MIKE
- - - A/ HIGH DESCENT PATH
O LOW DESCENT PATH 100 -
7o /
/
60 I I I I
40 50 60 70 80 TIME, SECONDS FIGURE 70 PHASE I APPROACH FLYOVER PNL, COMBINED JET COMPONENTS, CENTERLINE MIKE --- HIGH DESCENT PATH PATH DESCENT O LOW 80- 70- 60 / 5o I I I I I 40 50 60 70 80 TIME, SECONDS FIGURE 71 PHASE I AIRCRAFT APPROACH FLYOVER PNL, TURBINE-TURBOMACHINERY COMPONENT, CENTERLINE MIKE DESCENT PATH - - -/ HIGH
O LOW DESCENT PATH
110 - 100 - 90 -
-
70 80 50 60 TIME, SECONDS INLET COMPONENT, CENTERLINE MIKE PHASE I AIRCRAFT APPROACH FLYOVER PNL, COMPRESSOR FIGURE 72 - HIGH DESCENT PATH -- 0 LOW DESCENT PATH 120-
-A
A
70 80 50 60 TIME, SECONDS COMPONENTS, CENTERLINE MIKE FLYOVER PNL, COMBINED 73 PHASE I AIRCRAFT APPROACH FIGURE --- HIGH DESCENT PATH 0 LOW DESCENT PATH
-- a--
40 50 60 70 80 TIME, SECONDS FIGURE 74 PHASE I AIRCRAFT APPROACH FLYOVER PNL, FAN INLET COMPONENT, 710 FT. SIDELINE MIKE - - -L1 HIGH DESCENT PATH LOW DESCENT PATH O 110 -
90 -
40 50 60 70 TIME, SECONDS FIGURE 75 PHASE I AIRCRAFT APPROACH FLYOVER PNL, FAN EXHAUST COMPONENT, 710 FT. SIDELINE MIKE - - - A HIGH DESCENT PATH PATH LOW DESCENT O
90-
50 I 50 60 TIME, SECONDS 710 FT. SIDELINE MIKE PNL, COMBINED JET COMPONENT, APPROACH FLYOVER FIGURE 76 PHASE I AIRCRAFTPP HIGH DESCENT PATH - - - )O LOW DESCENT PATH 80 - 60o I 40 50 60 70 80 TIME, SECONDS COMPONENT, 710 FT. SIDELINE MIK FIGURE 77 PHASE I AIRCRAFT APPROACH FLYOVER PNL, TURBINE-TURBOMACHINERY - - - HIGH DESCENT PATH PATH DESCENT
0 LOW
- I I I TIME, SECONDS 710 FT. SIDELINE MIKE INLET COMPONENT, FLYOVER PNL, COMPRESSOR PHASE I AIRCRAFT APPROACH FIGURE 78 -A HIGH DESCENT PATH - - O LOW DESCENT PATH 70 80 40 50 60 SECONDS TIME, FT. SIDELINE MIKE PNL, COMBINED COMPONENTS, 710 79 PHASE I AIRCRAFT APPROACH FLYOVER FIGURE 600 -2000 FAN INL, 400- FAN INLET JET NOISE FAN EXHAUST -1000 -- - - - - ....
200- --- 7 CORE COMPRESSOR 600 -2000 -1000 0 1000 2000 3000 4000 5000 6000 7000 8000 FEET I I I I I I I I I I I -400 -200 0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400 METERS RUNWAY CENTERLINE DISTANCE FIGURE 80 PHASE I AIRCRAFT 95 PNL COMPONENT CONTOURS, LOW RISE TAKEOFF -2000 600- 400- CORE COMPRESSOR -1000 ,---- 4 200- - JET NOISE / ( o--0 TURBINE
\
N-- 200- -1000 FAN EXHAUST - - FAN INLET 400 - 600 -- -7000 -6000 -5000 - 000 -3000 -2000 -1000 0 1000 FEET I 1 I , -400 -200 0 200 METERS -2000 -1800 -1600 -1400 -1200 -1000 -800 -600 RUNWAY CENTERLINE DISTANCE 95 PNL COMPONENT CONTOURS, SHORT DESCENT APPROACH FIGURE 81 PHASE I AIRCRAFT I- WITH FLW CROSS
SWITHOUT
FLOW SCROSS S 70 FEET 4000 I I I I I I I I 2000 2200 1200 1400 MIETERS DISTANCE RUNWAY CENTERLINE PNL FLYOVER FAN INLET COMPONENT LOW RISE TAKE-OFF, CROSS FLOW EFFECT, I AIRCRAFT FIGURE 82 PHASE
WITH
.
CROSS FLOW
go
60II I I I FEET 4000 6000 7000 I I I I I I I I METERS 1200 1400 1600 1800 2000 2200 2400 2600 RUNWAY CENTERLINE DISTANCE FIGURE 83 PHASE I AIRCRAFT CROSS FLOW EFFECT, LOW RISE TAKE-OFF, FAN EXHAUST COMPONENT FLYOVER PNL .- ,A-. ,..
SWITHOUT I I I FEr 4000 5000 6000 7000 8000 900 I I I I I I I METERS 1200 1400 1600 1800 2000 2200 2400 2600 RUNWAY CENTERLINE DISTANCE FIGURE 84 PHASE I AIRCRAIT CROSS FLOW EFFECT, LOW RISE TAKE-OFF, JET EXHAUST COMPONENT FLYOVER PNL WITH I I 60I I I
6000 7000 8000
FEE 4000 5000
I I I I I I I I 2200 2400 2600 1600 1800 2000 METERS 1200 1400 RUNWAY CENTERLINE DISTANCE FLYOVER PNL CROSS FLOW EFFECT, LOW RISE TAKE-OFF, ALL COMPONENTS FIGURE 85 PHASE I AIRCRAFT OTT TOTAL AIRCRAFT 500 FT.
SIDELINE PNL, PNdB
CRUISE FAN INLET
CRUISE FAN EXHAUST i CRUISE FAN JET CRUISE TURBINE GAS GENERATOR INLET LIFT FAN INLZT t LIFT FAN JET LIFT FAN TURBINE REFERENCE CASE, FAN EXHAUST SUPPRESSION, NO NACELLE TREATMENT 105 -
102 I
SUPPRESSED NACEI.E 101 101 -10 GAS GENERATOR INLT.
-15 LIFT & LIFT/CRUISE FAN EXHAUST -10 LIFT/CRUISE FAN INLT
99 -
97 I
95 -
o -5 -10 -15 -20 LIFT FAN INLET SUPPRESSION, dB FIGURE 87 PHASE II AIRCRAFT FLYOVER PNL COMPARISON VARYING SUPPRESSION LEVEL ON LIFT FAN INLET