GIV Flight Crew Reference Library

airspeed for altitude (VMO) and Mach number. On airplanes Serial Number OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 2 October 11/01 Revision 5 (SN) 1000 to 1059 (except SN 1001 and 1034) not having Aircraft Service Change (ASC) 66, airspeed is indicated with a white pointer that rotates clockwise around the face of the instrument proportional to airplane speed and V MO by a “barber pole” striped pointer. Pitot/static connections provide the input for airspeed information. Although the indicator has a drum-type readout of Mach number in the upper center of the instrument, the ARINC 429 connections necessary to derive Mach speed information from the DADC are not installed. The OFF flag covering Mach readout will be displayed at all times on the instrument, indicating that this feature is not available. On airplanes SN 1060 and subsequent, and prior airplanes having ASC 66, the standby airspeed indicator is not powered (except for lighting circuits) and obtains speed information directly from the pitot/static system. On these airplanes, airspeed is indicated by a rotating white pointer, Mach number is read on an additional scale positioned on the outside perimeter of the airspeed scale and VMO / MMO is denoted with a red band on both the airspeed and Mach number scales. A knob on the lower face of the instrument is provided to set a movable airspeed reference bug (VREF). See the illustration in Figure 1. On all airplanes, the indicator is illuminated internally using 5V DC power from normal cockpit lighting circuits. C. Standby Altimeter: The standby altimeter provides an indication of airplane pressure altitude in event of primary flight display failure or malfunction. Altitude is indicated in twenty (20) foot increments within a range of one thousand (1,000) feet by a pointer that moves in front of the circular scale on the face of the instrument, making one revolution for every 1,000 feet. A drum-type counter in the center of the instrument provides graphic indications of altitude in hundred (100) and 1,000 foot increments. The local barometric pressure in inches of mercury (Hg) or millibars (Mb) is set with the knob on the lower corner of the instrument and displayed in windows in the instrument face. See the illustration in Figure 1. Like the standby airspeed indicator, the ARINC 429 connections necessary to derive altitude information from the DADCs are not installed. A yellow flag, labeled PNUE, is displayed at all times on the instrument, indicating that this feature is not available. The standby altimeter is powered by 28V DC from the Essential DC bus, and uses only pitot/static input for altitude determination. It is internally illuminated and has an electrically driven vibrator to smooth pointer movement. If electric power is lost, a VIB flag is displayed on the instrument and while indications will be valid, pointer movement may be intermittent, requiring occasional manual tapping on the face of the instrument during climb and descent. D. Static Air Temperature / Total Air Temperature (SAT / TAT) System: A heated Total Air Temperature probe is installed on the lower right forward fuselage to provide actual air temperature to the DADCs. See Figure 2 for a depiction of the probe. On the ground with electrical power and bleed air available, the probe is aspirated by bleed air through a dedicated line controlled by a solenoid operated valve that routes air into the probe housing, venting the air through holes in the probe to induce outside air OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 3 October 11/01 Revision 5 flow over the temperature sensing element. Air flow through the probe gives a more accurate reading of ambient conditions and avoids temperature increases associated with the heating effects of sunlight. Bleed air aspiration is controlled by the nutcracker (squat) switch system and requires 28V DC from the Right Main DC bus. The TAT probe is electrically heated when the airplane is airborne to prevent icing. E. Digital Air Data Computer System (DADC): Dual Honeywell AZ-810 Digital Air Data Computers (DADCs) are installed in the forward avionics racks. The DADCs are connected to the pitot/static system, with the pilot side pitot/static probe and ports connected to DADC #1 and the copilot side pitot/static sensors connected to DADC #2. Both DADCs are connected to the TAT probe for temperature data. The DADCs use the pneumatic and temperature data to compute correct airspeed, altitude, vertical speed, static source error correction (SSEC) and to send a signal to the audible tone generator initiating the overspeed “cricket” warning when airspeed reaches VMO/MMO. Other inputs used by the DADCs are Angle of Attack (AOA), flap handle position, barometric setting and pre-selected altitude. The DADCs formulate digital signals for elements of the airplane avionics system. The DADCs communicate data to the following: • Electronic Display System • Transponders • Flight Recorder • Flight Guidance Computer • Fault Warning Computer • Inertial Reference System • Flight Management System • Cabin Pressurization System • Stall Barrier System • Engine Pressure Ratio (EPR) Sensor • Traffic / Aircraft Collision Avoidance System (TCAS / ACAS) In order to maintain a continual crosscheck of system accuracy, it is recommended that the pilot select DADC #1 as a data source, and the copilot select DADC #2. Data source selection is made on the SENSOR page of the Display Controller. In this configuration, each pilot has an independent source for altitude, airspeed, AOA, vertical speed, SAT and TAS on their respective PFDs and navigation displays. If both pilots select the same DADC as data source, an amber annunciation is displayed on both PFDs. (If the pilot PFD is selected to DADC 2, both PFDs would display DADC 2 in amber in the upper right of the PFDs.) Data source selection for the guidance panel altitude pre-select is a function of the PFD command button (PFD-CMD). When the button indicates L, the data source is DADC #1, when R is displayed, data comes from DADC #2. Most subsystems with dual installations normally source DADC data according to a standard coupling arrangement: the left (L), #1 or pilot side sourced to the #1 DADC, and the right (R), #2 or copilot side connected to OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 4 October 11/01 Revision 5 the #2 DADC. For some, but not all installations, the data source is selectable to provide redundancy in case of DADC failure. Transponders (ATC) #1 and #2 are normally sourced to their respective DADC, but may be selected to the alternate DADC. Angle of Attack (AOA) indicators are referenced to the DADC selected to the respective PFD. EPR sensors are normally paired with engine #1 to DADC #1, engine #2 to DADC #2, but failure of a DADC will prompt an automatic switch to the remaining DADC for EPR computation. The DADC source for cabin pressure control is selectable on the cockpit overhead panel. DADC Failure Modes (Flagged, Unflagged) (1) A “flagged” DADC failure is one where the failure is readily apparent, because of the blue DADC 1 (or 2) FAIL advisory CAS message, and red “X’s” through all four air data scales (airspeed, altitude, AOA, and vertical speed) of the PFD using the failed DADC as its air data source, as selected on the display controllers. Other confirmation of failure is as follows: • Transponder indications • AOA indexer failure • Automatic cabin pressurization control problems and faulty guidance panel indications (if operating on the failed DADC) • EICAS message indicating that EPR is receiving pressure information from the opposite DADC (EPR 1 - DADC 2, or EPR 2 -DADC 1) The solution is to select the opposite (good) DADC as the air data source, on display controllers, guidance panel, cabin pressure control panel, etc. OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 5 October 11/01 Revision 5 (2) An “unflagged” DADC failure will produce a blue DADC MISCOMPARE advisory CAS message, and the failure may not be readily apparent. The autopilot and yaw damper will disconnect and will not re-engage until the faulty DADC has been identified and isolated by pulling its circuit breaker. Pitch trim will remain operative. The flight crew may be able to identify the faulty DADC by looking for an amber IAS and / or ALT comparator warning annunciation to left of the horizon in each PFD. The IAS indication means a split of 20 or more knots exists between air data systems; the ALT indication means a split of 200 feet or more exists between systems. To determine which system is correct requires reference to an independent data source, in this case standby flight instrumentation. Since the standby flight instruments show large errors because they are uncorrected for static source error, it is recommended that standby altimeter be set so as to read the same as the cruising flight level. Once stable cruise speed is attained, the settable airspeed bug should be aligned with the standby airspeed pointer. Thus, reference can be made to the standby altimeter and airspeed indications, as “voters” in helping to determine which DADC outputs are more nearly correct. Then, check the other DADC outputs, the pressurization system, AOA indexers and transponders, for indications of faulty operation. If observation leads to a determination of which DADC is faulty, select the “good” DADC to both PFDs, guidance panel, transponders, and the cabin pressurization system. Then isolate the faulty DADC by pulling its circuit breaker, and after at least a one minute wait, re-engage the autopilot. 3. Controls and Indications: (See Figure 1.) NOTE: A description of the SPZ-8000 (or SPZ-8400) Digital Automatic Flight Control System (DAFCS) can be found in Honeywell’s SPZ-8000 (or SPZ-8400) Digital Automatic Flight Control System Pilot’s Manual for the Gulfstream IV. A description of the Integrated Automatic Tuning System (Collins RTU-4200 Series Radio Tuning Unit (RTU)) can be found in Section 2A-23-40, Integrated Automatic Tuning System and Collins’ RTU-4200 Series Pilot’s Guide. A. Circuit Breakers (CBs): Circuit Breaker Name CB Panel Location Power Source TOTAL TEMP PROBE HTR CP L-10 MAIN 115V AC φB TOTAL TEMP VALVE CP M-10 R MAIN 28V DC L PITOT HT PWR CP L-11 ESS 115V AC φA R PITOT HT PWR CP M-11 MAIN 115V AC φA L PITOT HT CONT CP L-12 ESS 28V DC R PITOT HT CONT CP M-12 MAIN 28V DC OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 6 October 11/01 Revision 5 Circuit Breaker Name CB Panel Location Power Source STBY PITOT HT CONT CP L-13 ESS 28V DC STBY PITOT HT PWR CP M-13 ESS 115V AC φA AOA PRB HTR #1 CP L-14 ESS 28V DC AOA PRB HTR #2 CP M-14 MAIN 28V DC DADC #1 CP F-3 ESS 28V DC DADC #2 CP G-3 MAIN 28V DC STBY AIR SPD IND CP H-4 (1) EMER 28V DC DUAL MODE ALTM VIB CP H-3 (1) EMER 28V DC STBY ALTM VIB CP H-3 (2) EMER 28V DC DUAL MODE ALTM CP H-4 (3) ESS 28V DC STBY ALTM VIB CP H-4 (4) EMER 28V DC NOTE(S): (1) SN 1000 -1059 (except 1001 and 1034) not having ASC 66 (2) SN 1000, 1002-1122 (except 1034) having ASC 66, SN 1001, and 1060 - 1167 (3) SN 1000, 1002 - 1059 (except 1034) not having ASC 66 (4) SN 1034, 1168 and subs B. Caution (Amber) CAS Messages: CAS Message Cause or Meaning AOA HEAT 1-2 FAIL Angle of attack probe heater failed L-R PITOT HT FAIL Indicated pitot tube heater elements not energized SSEC DISABLED Static source error correction to DADC has been disabled STBY PITOT HT FAIL Standby pitot heater elements not energized TAT PROBE HT FAIL TAT probe heater has failed C. Advisory (Blue) CAS Messages: CAS Message Cause or Meaning DADC 1-2 FAIL A DADC has failed DADC MISCOMPARE The priority FGC has detected an unflagged miscompare between DADC 1 and DADC 2 EPR 1 - DADC 2 EPR 2 - DADC 1 DADC malfunction has caused remaining DADC to supply information to both EPR systems 4. Limitations: There are no limitations to this system at the time of this revision. OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 7 October 11/01 Revision 5 Standby Flight Instruments Figure 1 OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 8 October 11/01 Revision 5 SAT / TAT Probe Figure 2 OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 9 October 11/01 Revision 5 OPERATING MANUAL THIS PAGE IS INTENTIONALLY LEFT BLANK. PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 10 October 11/01 Pitot / Static System Schematic Figure 3 OPERATING MANUAL 2A-34-00 Page 11 / 12 October 11/01 2A-34-30: Attitude and Direction System 1. General Description The standby attitude and direction systems provide references for steering the airplane in the desired direction using basic instruments that remain powered during instances of failure / malfunction of the Primary Flight Displays (PFDs) and / or the Flight Management System (FMS). The following subsystems, units and components are included: • Standby Attitude Indicator • Standby Directional System 2. Description of Subsystems, Units and Components: A. Standby Attitude Indicator: The standby attitude indicator (shown in Figure 1) is a gyroscopically driven artificial horizon that provides a backup indication of airplane pitch and roll in the event of a failure or malfunction of PFDs, FMS or IRS systems. The indicator contains a sphere divided into hemispheres painted blue and brown (or black) representing sky and earth. Markings on the hemispheres denote pitch attitude in five degree (5°) increments from level up or down to eighty degrees (80°). When the airplane is initially powered, the indicator will power-up and self-erect once the internal gyroscope reaches operating speed. To immediately erect the indicator, use the cage knob on the face of the instrument, orienting the sphere upright and leveling the horizon (where the sky and earth representations meet). The airplane symbol on the face of the instrument is adjusted to match the airplane pitch attitude by rotating the cage knob. At the top of the instrument is a triangular pointer that indicates airplane bank angle against the semicircular scale surrounding the artificial horizon. The scale is marked in ten degree (10°) increments up to thirty degrees (30°) of bank, and additional marks at forty-five degrees (45°) (for Serial Number (SN) 1330 and subsequent only), sixty degrees (60°) and ninety degrees (90°). The standby attitude indicator is powered by the Emergency DC bus. If power to the instrument is interrupted, a red warning flag is displayed on the face of the instrument (the flag is also displayed when the indicator is caged). If Emergency DC bus power to the indicator is lost (battery depleted - warning flag displayed) the rate of spin of the gyro may be sufficient to supply attitude information for several minutes before becoming unreliable. On airplanes SN 1330 and subsequent, the standby attitude indicator has pointers for glideslope and localizer signals, providing guidance for an ILS approach. ILS information is supplied by VHF NAV #1 over an ARINC 429 data bus. A knob on the lower left corner of the attitude indicator is used to select signal input to the glideslope and localizer pointers. The knob has three (3) positions: OFF, ILS and B/C (for a back course approach). Both the glideslope and localizer pointers have a warning flag to indicate power off or lack of signal reception. B. Digital Bearing and Distance Indicator (DBDI): The dual DBDI (pilot and copilot) indicators provide a standby display of heading, bearing, and distance to a selected navigation source OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 13 October 11/01 Revision 5 independent of the Primary Flight Display (PFD). The indicators have dual power supplies, each powered by the Essential or Emergency DC bus, with only basic heading information available when operating on Emergency DC bus power. The DBDI is illustrated in Figure 4. During normal operation with all electrical sources available, the DBDIs are powered through the Essential DC bus and display the following information: • Airplane heading beneath the lubber line at the top of the compass card, sourced from the IRS system in use (pilot on #1, copilot on #2). • Pointer #1 (single shaft arrow) pointing to the currently tuned navigational radio transmitter (VOR / VORTAC or ADF) selected with the pointer switch on the lower left of the instrument. The pointer will be positioned to the three o’clock position and a flag displayed if no navigation radio is tuned or the signal is out of range for the transmitter type selected. • Pointer #2 (double shaft arrow) pointing to the currently tuned navigational radio transmitter (VOR / VORTAC or ADF) selected with the pointer switch on the lower right of the instrument. The pointer will be positioned to the three o’clock and a flag displayed if no nave radio is tuned or the signal is out of range for the transmitter type selected. • Digital DME distance readout is displayed in the window in the top of the instrument for both (1 and 2) currently tuned VORTACs (only dashes are displayed if no VORTAC is currently tuned). Distance is indicated in one-tenth mile (0.1) increments up to 99.9 nautical miles and one mile increments from 100 to 999 nautical miles. • Digital display of the frequency of the currently tuned VORTAC if the NAV selector is placed in HOLD mode, with the frequency preceded by an H to indicate that HOLD has been selected. In normal NAV mode, only dashes are displayed in the frequency space. A failure of the heading information source (IRS #1 and IRS #2) prompts the DBDI to automatically switch to an alternate heading source if one is installed (typically AHRS or IRS #3). The use of an alternate heading source is annunciated on the face of the instrument by the illumination of a green AHDG light in the upper right corner of the instrument. A more severe failure that involves the loss of primary and alternate heading reference sources would automatically switch the DBDI to standby mode, annunciated by the illumination of the amber STBY light in the upper right of the indicator. In standby mode, the heading reference source is the dual flux detector installation in the airplane wing tips. The flux detectors act as magnetic compasses, sensing the horizontal component of the magnetic field surrounding the earth. The magnetic direction sensed by the flux detectors is corrected for errors (induced by the metallic structure of the airplane) by a magnetic compensator before it is sourced to the DBDI for use as the heading reference in standby mode. Should there be a failure of the standby / flux detector system, a red STBY light illuminates in the upper right corner of the instrument. The red STBY will illuminate with a standby system failure even if the DBDI is operating in the normal (IRS) mode. OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 14 October 11/01 Revision 5 The DBDI indicators annunciate system degradation and/or subcomponent failure with the following displays: • OFF flag in the upper left of the instrument indicates loss of instrument power • HDG flag at the lubber line at the top of the instrument indicates an invalid compass signal • Single shaft arrow flag on the left of the instrument indicates invalid signal to the #1 pointer • Double shaft arrow flag on the right of the instrument indicates invalid signal to the #2 pointer All of the mode annunciations and system / subcomponent failure annunciations may be tested on the ground during preflight with the ST/R switch (momentary) on the upper right of the heading display. This test feature is wired through the nutcracker (squat) switch system to operate in the ST or self-test mode on the ground and the R or reset mode in the air. Pressing the ST/R button in the air will reset the heading indicator, recapturing a primary or alternate heading source if one is available. Pressing the ST/R button during a ground preflight will illuminate the mode annunciations, display warning flags and indicate a DBDI malfunction by a five (5) second flashing red STBY light followed by continuous illumination of the light. On airplanes having Aircraft Service Change (ASC) 217, DBDI MANUAL STBY switches are installed on the outboard side of the pilot and copilot forward instrument panels, one for each DBDI. The installation is shown in Figure 5. (A switch that enables manual selection of the standby mode is located on the face of the DBDI electronic module in the radio rack on airplanes not having ASC 217). This switch allows the crew to manually select the standby (STBY) heading mode in flight to crosscheck inertial (IRS) heading information, compensate for faulty IRS information, or to select a heading source during realignment of the IRSs. 3. Controls and Indications: (See Figure 4 and Figure 5.) A. Circuit Breakers (CBs): Circuit Breaker Name CB Panel Location Power Source STBY HORZN CP E-4 EMER 28V DC DBDI #1 (SN 1212 & subs) (DDRMI #1 on SN 1000-1211) CP F-4 ESS 28V DC DBDI #2 (SN 1212 & subs) (DDRMI #2 on SN 1000-1211) CP G-4 ESS 28V DC E DBDI #1 (SN 1212 & subs) (E DDRMI #1 on SN 1000-1211) CP H-5 EMERG 28V DC 1C E DBDI #2 (SN 1212 & subs) (E DDRMI #2 on SN 1000-1211) CP I-5 EMERG 28V DC 2B 4. Limitations: There are no limitations for this system at the time of this revision. OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 15 October 11/01 Revision 5 Digital Bearing and Distance Indicator Figure 4 OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 16 October 11/01 Revision 5 DBDI MANUAL STBY Switch Installation Figure 5 OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 17 October 11/01 Revision 5 2A-34-40: Radio Altimeter System 1. General Description: The GIV is equipped with two independent AA-300 radio altimeters. Each has a dedicated Receiver / Transmitter (R/T) unit, transmitting antenna and receiving antenna. (Antenna location is shown in Figure 27.) There are no off / on controls (switches) or separate displays for the radio altimeters. The radio altimeters operate continuously when the airplane Main DC buses are powered, using high resolution, short pulse radar signals that are accurate over wide variations of terrain, target reflectivity, weather and airplane altitude. The radio altimeters provide a continuous readout of airplane altitude above ground level in the operating range of zero to twenty-five hundred (0-2,500) feet. Accuracy of the altitude readout varies with height above ground, with readings between zero and one hundred (0 and 100) feet accurate to within three (3) feet, readings between one hundred and five hundred (100-500) feet have an accuracy within three percent (3%), and readings between five hundred and twenty-five hundred (500-2,500) feet accurate within four percent (4%). Above twenty-five hundred (2,500) feet, the radio altimeters continue to operate, however the radio altitude information is no longer displayed because of the increase in error margin at higher altitudes. 2. System Operation: Radio altimeter data is sent to the Data Acquisition Units (DAUs) to be digitized and then forwarded over the Avionics Standard Communications Bus (ASCB) to the symbol generators for display on the Primary Flight Display (PFD). A discrete signal is also provided to the landing gear indication system to provide the altitude warning at twelve hundred (1,200) feet if the landing gear is not down and locked (see the discussion in Section 2A-32-30, Extension and Retraction System of this manual). The PFD displays of radio altitude differ slightly between airplanes with SPZ-8000 and SPZ-8400 Digital Automatic Flight Control Systems (DAFCS). See Figure 6 and Figure 7 for illustrations of the radio altitude display formats. A. SPZ-8000 Radio Altimeter Display: The display of radio altitude on the PFD is selected using the SENSOR function on the Display Controller (DC). When SENSOR is selected, a menu appears on the screen of the DC with the available data display options. Pushing the appropriate Line Select Key (LSK) adjacent to the menu item will select that sensor data for display on the PFD. When Radio Altitude (RAD ALT) is displayed, it is shown in digital format just outside the lower right corner of the attitude display. The white digital readout is in ten (10) foot increments between twenty-five hundred (2,500) feet and two hundred (200) feet, and five (5) foot increments below two hundred (200) feet. If the dual radio altimeters are paired on-side (pilot selected to radio altimeter #1 and copilot selected to radio altimeter #2) the source of the altimeter data is not shown. If the pilot and copilot have selected off-side radio altimeters (pilot to #2 and copilot to #1) the letters RA, and the numbers 1 or 2 as appropriate, are shown in white immediately to the right of the digital readout. If both pilot and copilot are selected to the same radio altimeter, the RA is shown in amber. (The pilot and copilot can select radio altimeter data source with options on the DC.) OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 18 October 11/01 Revision 5 A reference set option on the DC allows entering a radio altitude reference for use as a visual indication of Decision Height (DH) during precision approaches predicated on radio altitude data. Pushing the FLT REF button on the DC displays the menu containing RAD ALT. A value for radio altitude DH is entered with the rotary set knob and selected for display with the LSK. The selected DH is displayed on the PFD just above the readout of current radio altitude. As the airplane descends to the selected DH, a flashing white box is displayed around the current radio altitude when it is equal to the selected DH. The white box flashes for five (5) seconds after reaching DH, and remains displayed as long as airplane radio altitude is less than the DH. When a valid ILS frequency is received for an approach and the airplane descends below two hundred (200) feet radio altitude, a yellow runway symbol is displayed on the PFD, rising from the bottom of the attitude display up to meet the airplane symbol on runway contact at landing. The symbol also moves laterally to indicate displacement from localizer centerline. An additional reminder of airplane altitude is shown on the altitude tape on the right side of the PFD. As the airplane descends below six hundred (600) feet radio altitude, the color of the altitude tape changes to brown, indicating proximity the ground. The brown altitude tape extends from six hundred (600) feet down to zero (0) feet radio altitude. NOTE: This altitude reminder should not be confused with the radio altitude display. The brown portion of the altitude tape corresponds to airplane terrain clearance at a given height above mean sea level (with barometric altimeter set to QNH). For instance, if the airplane is landing on a runway with an elevation of one thousand twenty (1,020) feet MSL, the altitude tape color will change from blue to brown as the airplane descends through one thousand six hundred twenty (1,620) feet MSL. If there is a system malfunction that causes a loss of valid radio altimeter data, the white digital radio altitude readout is replaced by amber dashes (“- - - - “). If the yellow runway symbol is displayed at the time of the failure, the symbol is removed from the PFD. B. SPZ-8400 Radio Altitude Display: The display of radio altitude on the PFD is selected using the SENSOR function on the Display Controller (DC). When the SENSOR button is selected, a menu appears on the screen of the DC with the available data display options. Pushing the appropriate Line Select Key (LSK) adjacent to the menu item will select that sensor data for display on the PFD. When radio altitude (RAD ALT) is displayed, it is shown in digital format at the bottom of the attitude display. The digital readout is in green, indicated in ten (10) foot increments between twenty-five hundred (2,500) feet and two hundred (200) feet, and five (5) foot increments below two hundred (200) feet. If the dual radio altimeters are paired on-side (pilot selected to radio OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 19 October 11/01 Revision 5 altimeter #1 and copilot selected to radio altimeter #2) the source of the altimeter data is not shown. If the pilot and copilot have selected off-side radio altimeters (pilot to #2 and copilot to #1) the letters RA, and the numbers 1 or 2 as appropriate, are shown in white immediately to the right of the digital readout. If both pilot and copilot are selected to the same radio altimeter, the RA is shown in amber. (The pilot and copilot can select radio altimeter data source with options on the DC.) A reference set option on the DC allows entering a radio altitude reference for use as a visual indication of Decision Height (DH) during precision approaches predicated on radio altitude data. A DH must be entered when the airplane is one hundred (100) feet or more above the desired DH. Pushing the FLT REF button on the DC displays the menu containing RAD ALT. A value for radio altitude DH is entered with the rotary set knob and selected for display with the LSK. The selected DH is displayed on the PFD outside the lower right corner of the attitude indicator. As the airplane descends to the selected DH, an empty box symbol is displayed in the upper right corner of the attitude display when the airplane is within one hundred (100) feet of the selected DH. When the airplane descends to the set DH, an amber DH annunciation is displayed in the box. The DH symbol flashes for five (5) seconds, then remains displayed whenever the airplane is below DH. The readout of actual radio altitude (displayed at the bottom of the attitude indicator) changes color from green to amber when the airplane is one hundred (100) feet or less above the selected DH. When a valid ILS frequency is received for an approach and the airplane descends below two hundred (200) feet radio altitude, a yellow runway symbol is displayed on the PFD, rising from the bottom of the attitude display up to meet the airplane symbol on runway contact at landing. The symbol also moves laterally to indicate displacement from localizer centerline. An additional reminder of airplane altitude is shown on the altitude tape on the right side of the PFD. As the airplane descends below six hundred (600) feet radio altitude, the color of the altitude tape changes to brown, indicating proximity the ground. The brown altitude tape extends from six hundred (600) feet down to zero (0) feet radio altitude. A yellow line appears at the top of the brown portion of the tape. The line flashes for the first ten (10) seconds after the brown tape is displayed or until the airplane descends to four hundred (400) feet radio altitude, whichever occurs first. The yellow line rides in front of the brown altitude tape display, indicating height above touchdown. NOTE: This altitude reminder should not be confused with the radio altitude display. The brown portion of the altitude tape corresponds to airplane terrain clearance at a given height above mean sea level (with barometric altimeter set to QNH). For instance, if the airplane is landing on a runway with an elevation of one thousand twenty (1,020) feet MSL, the altitude tape color will change from gray to brown as the airplane descends through one thousand six hundred twenty (1,620) feet MSL. OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 20 October 11/01 Revision 5 If there is a system malfunction that causes a loss of valid radio altimeter data, the white digital radio altitude readout (and DH setting if selected) is replaced by amber dashes (“- - - - “). If the yellow runway symbol is displayed at the time of the failure, the symbol is removed from the PFD. 3. Controls and Indications: There are no separate controls or indicators for the radio altimeter system. All cockpit interface with the system is through the DCs and the EFIS (PFD) display system. When the airplane is on the ground with full electrical power, the normal radio altitude readout is -5 (minus five) feet ± 5 feet. A radio altimeter self-test may be initiated (on-side test only: pilot tests RAD ALT #1, copilot tests RAD ALT #2) using the LSK labeled RAD ALT on the TEST menu of the DC. When the test is in progress, a radio altitude of one hundred (100) feet should be displayed on the PFD: • Preflight: Entering a DH of 50 feet prior to performing the radio altimeter self-test will test the DH display on the PFD. • In-Flight Test: Entering a DH of 200 feet prior to performing the radio altimeter self-test will test the DH display on the PFD. NOTE: The radio altimeter self-test is inhibited with the AFCS engaged. The self-test is also inhibited by the fault warning computer during certain flight director modes. A. Circuit Breakers (CBs): Circuit Breaker Name CB Panel Location Power Source RADIO ALT #1 CPO I - 4 L MAIN 28V DC RADIO ALT #2 CPO J - 4 R MAIN 28V DC B. Advisory (Blue) CAS Messages: CAS Message Cause or Meaning RAD ALT 1 - 2 FAIL Indicated radio altimeter(s) has failed 4. Limitations: There are no limitations associated with this system at the time of this revision. OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 21 October 11/01 Revision 5 SPZ-8000 Radar Altitude Display Figure 6 OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 22 October 11/01 Revision 5 SPZ-8400 Radar Altitude Display Figure 7 OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 23 October 11/01 Revision 5 2A-34-50: Enhanced Ground Proximity Warning System (EGPWS) 1. General Description: The Enhanced Ground Proximity Warning System (EGPWS) is installed during production beginning with airplanes Serial Number (SN) 1390 and subsequent. (The following system description is applicable to the production installed system only. Operators with systems installed by completion outfitters should consult the documentation supplied by the outfitter.) EGPWS provides aural and visual alerts to prevent Controlled Flight Into Terrain (CFIT). Alerts are generated in conditions of terrain clearance danger, severe windshear and excessive deviation below an Instrument Landing System (ILS) glideslope. EGPWS also provides aural notification of excessive bank angles and provides height above runway callouts, including approach minimums, during final approach. 2. Subsystems, Units and Components: The EGPWS consists of a computer and geographical database interfaced with the SPZ-8400 DAFCS and airplane subsystems over ARINC 429 busses and discrete connections for data sensing and display presentation. See the system diagram in Figure 8. The system uses inputs from the DADCs, radio altimeter, FMS/GPS/IRS, angle of attack (AOA), landing gear and flap position, navigation data and a manually entered approach decision height. This information is integrated with the database in the computer to produce the aural and visual alert messages and the Terrain Awareness Display (TAD) graphic on the cockpit EFIS displays. (The TAD is usually selected to the NAV display, however, the Display Controller has an EGPWS option that allows selection of the TAD to the PFD, with the TAD shown on the HSI similar to the radar display.) Aural alerts and warnings are transmitted over cockpit speakers and through the cockpit interphone system, while alert and warning text messages are displayed on the Primary Flight Display (PFD). EGPWS aural alerts and warnings, except the windshear alert / warning can be inhibited with the GPWS VOICE O-RIDE switch on the O-RIDES panel on the center pedestal, shown in Figure 9 (location may vary). The computer is located in the right electronic equipment rack and is powered from φC of the Left Main 115V AC bus and the Left Main 28V DC bus. The system operates in seven (7) distinct modes: • Mode 1 - Excessive descent rate. • Mode 2 - Excessive terrain closure rate • Mode 3 - Altitude loss after takeoff • Mode 4 - Unsafe terrain clearance • Mode 5 - Excessive deviation below glideslope • Mode 6 - Advisory callouts • Mode 7 - Windshear alerting The basic seven modes of operation are available in earlier model GPWS systems, with the alerts and warnings formulated using only airplane sensor data (airspeed, radio altitude, etc.). With the EGPWS, the ability to compare present airplane position, and predicted flight path vectors with data in the geographical database provides expanded warning envelopes and display options that increase situational awareness. System enhancements improve the basic modes of operation and offer features not previously available. A Terrain Awareness Display (TAD) feature provides a graphic of terrain ahead of the airplane’s current flight path. The TAD graphic is in OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 24 October 11/01 Revision 5 multicolor and can be selected for continuous view on the NAV display (or PFD in the HSI position). If not selected for continuous view, the TAD will automatically “pop up” on the NAV display when the EGPWS computer detects terrain conflicts. Terrain displayed is within the range selected. The display range is adjusted with the same control as the weather radar, however if the TAD is not selected for continuous display and subsequently “pops up” the default range is ten (10) nautical miles - the range may then be adjusted from the default value. On the TAD, the color red is used to indicate the highest and most hazardous terrain areas, yellow (in varied intensity) identifies less dangerous terrain at elevations equal to or higher than airplane altitude, and green (in varied intensity) denotes areas equal to or below airplane altitude. NOTE: The TERR INHIB switch on the O-RIDES panel on the center pedestal, shown in Figure 9, will prevent the “pop up” of the TAD. If TERR INHIB is selected, the basic EGPWS modes 1 - 7 will continue to provide terrain clearance / windshear alerts, but indications will be limited to aural alerts over speakers and interphone and visual text alerts on the PFD. Features of the Terrain Awareness Display include the following: • Obstacles are displayed on the TAD when the airplane’s flight path will conflict with any of the known obstacles in the EGPWS database. (The database does not include temporary man-made obstacles covered in NOTAMS). • A Terrain Peaks feature enhances situational awareness with a digital readout of elevations of the highest and lowest terrain and additional color gradations to further define terrain. • A Terrain Clearance Floor (TCF) feature alerts the crew of a premature descent based upon current airplane position relative to the nearest runway. The TCF feature is useful in non-precision approaches and is enabled with TAD. • On airplanes with EGPWS software build -210 -210 (SN 1426 and subsequent), a Runway Field Clearance Floor (RFCF) feature based on airplane position and height above destination runway using a computed Geometric Altitude (GA) provides improved safety margins at locations where the runway is higher than surrounding terrain. • Geometric Altitude is computed blend of altitude information including GPS data, and at lower altitudes enhanced with Radio Altitude, to reduce or eliminate altimeter errors induced by non standard atmospheric conditions or reference setting errors. • A EGPWS Envelope Modulation feature is incorporated that compensates for terrain and obstacles at some airports that have historically generated nuisance alerts, or that have environmental characteristics that inhibit needed alerts. OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 25 October 11/01 Revision 5 3. Basic Mode Functions: NOTE: Basic modes 1 - 6 require radio altimeter information to function. If radio altimeter information is not available, the TAD will continue to provide terrain awareness using Geometric Altitude (GA) inputs (see the discussion of GA in the following text). A. Mode 1: Excessive Descent Rate: Excessive descent rate alerts and warnings are generated when the descent is too steep for the margin of altitude below the airplane. The alert / warning envelope upper boundary is approximately 2,500’ radio altitude, and within the envelope, the alert / warning logic is biased for the amount of recovery time for the hazardous condition. See Figure 10. At 2,500’ a descent of approximately 4500 feet per minute (FPM) would initiate a “SINK RATE, SINK RATE” aural alert annunciation, and a descent of approximately 7000 FPM would prompt a “WHOOP, WHOOP, PULL UP” aural warning and the text PULL UP in red is displayed on the PFD. At lower radio altitudes, corresponding lower rates of descent will initiate alerts and warnings, and the envelope margin between alerts and warnings narrows. If a valid Instrument Landing System (ILS) front course signal has been tuned and received, and the airplane is descending to capture the glideslope from above, the margin of the SINK RATE alert envelope is desensitized to prevent unwanted alerts when the airplane is in a safe position to capture (or recapture) the glideslope. B. Mode 2: Excessive Terrain Closure Rate: Mode 2 is the inverse of Mode 1 in that in this instance the airplane is in level flight, but is in danger of impacting rapidly rising terrain. Mode 2 is also based on radio altitude and the alert / warning envelope predicated upon closure rates and time remaining for evasive maneuvers. Mode 2 is split into two sub-modes with different parameters depending upon airplane configuration. Sub-mode 2A is operable during climbout, cruise and initial approach (defined as flaps not in landing configuration and airplane not on ILS centerline). See the envelope shown in Figure 11. In these circumstances, if the airplane approaches rising terrain at a speed such that avoidance time is limited, initially an aural “TERRAIN, TERRAIN” alert message is prompted, and an amber TERRAIN text message is displayed on the PFD. If conditions deteriorate such that ground contact is imminent, an aural “WHOOP, WHOOP, PULL UP, PULL UP” warning is heard over cockpit speakers and headsets, and a red PULL UP text message is displayed on the PFD. The aural and text annunciations will continue until terrain clearance is sufficient that the warning envelope is cleared. If terrain clearance does not continue to increase, the TERRAIN aural and text alerts will continue. In all instances, the visual text alert will continue to be displayed on the PFD until the airplane has gained 300 feet of altitude, forty-five (45) seconds have elapsed, landing flaps have been selected or the flap override switch has been activated. OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 26 October 11/01 Revision 5 Sub-mode 2B is a desensitized alert and warning envelope that is automatically activated when landing flaps are selected (or flap override activated), or when within two (2) dots of the centerline of glideslope and localizer during an ILS approach. See Figure 12. This mode is also active during the first sixty (60) seconds after takeoff. The alerts and warnings in sub-mode 2B are the same as those in sub-mode 2A, with additional provisions that if the airplane enters the boundaries of the warning envelope without gear or flaps in the landing configuration, the aural “TERRAIN, TERRAIN” alert will sound with the accompanying text message on the PFD. Further penetration of the envelope will result in “PULL UP” aural warnings and text message until the airplane exits the envelope or the airplane configuration is corrected. If the airplane configuration is correct for landing (gear and flaps down), and a hazardous terrain closure rate exists, the “PULL UP” aural and text warnings are suppressed, and the “TERRAIN” aural and text alerts are prompted until the airplane exits the sub-mode 2B envelope. C. Mode 3: Altitude Loss after Takeoff: This mode provides an aural alert for any significant altitude loss after takeoff or when performing a go-around at an altitude of less than two hundred forty-five feet (245’) radio altitude with the gear and flaps not in the landing configuration. The alert envelope, shown in Figure 13, is predicated upon the amount of terrain clearance available below the airplane versus sink rate. Any significant loss of altitude prompts an aural alert of “DON’T SINK, DON’T SINK”. The aural alert is sounded twice only, unless there is a continued loss of altitude clearance. D. Mode 4: Unsafe Terrain Clearance: Mode 4 is subdivided into three sub-modes to address specific phases of flight, airplane configurations and airspeeds. The sub-modes 4A, 4B and 4C are active in circumstances similar to those that prompt alerts and warnings under Mode 2 and Mode 3, but provide increased situational awareness when hazardous conditions are not as immediate. Sub-mode 4A is active during cruise and approach with gear and flaps up, with the alerting envelope predicated on speed and altitude. See Figure 14. (This envelope also provides additional protection against a gear-up landing). Flying in altitude and airspeeds from 1000 feet radio altitude at a speed of 250 knots down to an altitude of 500 feet and a speed of 190 knots prompts an aural “TOO LOW TERRAIN” alert over speakers and headsets and an amber text message TERRAIN on the PFD. If the airplane is still in the clean configuration below 500 feet and at less than 190 knots, the aural alert changes to “TOO LOW GEAR”. Either of these aural alerts is sounded only once, unless there is further decrease of altitude / airspeed of twenty percent (20%) or more. Sub-mode 4B operates during cruise and approach with the landing gear down, but with the flaps not in landing configuration. See the envelope depicted in Figure 14. Below 1000 feet at 250 knots down to 245 feet at 159 knots with the flaps not fully extended prompts a “TOO LOW TERRAIN” aural alert and the display of an amber TERRAIN on the PFD. Below 245 feet and less than 159 knots, the aural alert changes to “TOO LOW FLAPS”. The aural alerts are sounded only once unless there is a further twenty percent (20%) degradation of clearance. OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 27 October 11/01 Revision 5 Sub-mode 4C operates during climbout toward rising terrain that produces a decrease in vertical clearance, but is not severe enough to prompt activation of mode 2. See the alert envelope shown in Figure 15. After takeoff or a go-around below 245 feet, and the gear and flaps not in landing configuration, the airplane must continue to gain terrain clearance at a rate that is equal to or exceeds 75% of the radio altitude averaged over the previous fifteen (15) seconds, with no decrease. This envelope is upwardly limited at 500 feet radio altitude at airspeeds less than 190 knots, and expands linearly to 1000 feet at 250 knots. If airplane climb does not meet the envelope gradients, an aural alert “TOO LOW TERRAIN” is heard and the TERRAIN text alert is displayed on the PFD. E. Mode 5: Excessive Deviation Below Glideslope: Mode 5 provides terrain clearance alerts during ILS approaches. The alerts are triggered at two different levels, depending upon how closely the airplane is aligned with the glideslope and the terrain clearance available below the airplane. The alerting envelope is shown in Figure 15. For glideslope alerts to be operative, the airplane must be within two (2) dots of localizer centerline, gear and flaps in the landing configuration and a valid front course ILS signal received. As the airplane descends below 1000 feet radio altitude on the localizer, any deviation below glideslope center that exceeds 1.3 dots prompts an aural “GLIDESLOPE” alert and illumination of the BELOW G/S lights below the cockpit glareshield. This aural alert is sounded at only half of the volume of normal aural alerts, and is called a “soft” alert. If the airplane deviates twenty percent (20%) further from the 1.3 dot displacement, the “soft” alert is repeated at increasingly faster rates. The BELOW G/S light is a dual function switchlight installation. The top half of the switchlight is labelled BELOW G/S and illuminates amber when the airplane deviates outside of the glideslope alerting envelope. The bottom half of the light is labelled G/S INHIBIT. Pushing the switchlight will inhibit further glideslope alerts. When the inhibit function is selected by pushing the switchlight, the legend G/S INHIBIT illuminates blue. The inhibit switchlight may be used to cancel Mode 5 alerts at any time the airplane is below 2000 feet radio altitude. Once cancelled, Mode 5 alerting is reset when the airplane descends below 30 feet, climbs above 2000 feet or the ILS frequency is deselected then retuned. Mode 5 would then be available for a subsequent approach in the event of a go-around As the airplane descends to 300 feet and lower during the ILS approach, a deviation from glideslope center of two (2) dots or more prompts aural alerts “GLIDESLOPE” at normal (louder) volume. The aural alert is sounded every three (3) seconds until the airplane returns to within 1.3 dots of glideslope center. Both the 1.3 dot “soft” alert and the 2 dot normal aural alerts are desensitized below 150 feet radio altitude to allow for glideslope beam variations and to reduce the possibility of nuisance (unwarranted) alerts. If the airplane is maneuvering at low altitude to capture the localizer for an ILS approach, the upper altitude limit of the glideslope deviation alert envelope is reduced to 500 feet radio altitude if the airplane is descending at less than 500 FPM. . OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 28 October 11/01 Revision 5 F. Mode 6: Advisory Callouts: The mode 6 advisory callouts are aural notifications of specific altitudes and excessive bank angle. There are no visual text messages or displays associated with mode 6. The specific altitudes announced over the cockpit speakers and interphone system are selected upon installation of the EGPWS system, as are the optional instrument approach minimum altitude and excessive bank angle callouts. The following altitude callouts are most commonly selected, but others may be selected by individual operators. Different selections should be noted by system placards in the cockpit (if confirmation of selected altitudes is required, note the callouts during EGPWS self-test): • “ONE THOUSAND” • “FIVE HUNDRED” • “FOUR HUNDRED” • “THREE HUNDRED” • “TWO HUNDRED” • “ONE HUNDRED” • “FIFTY” • “FORTY” • “THIRTY” • “TWENTY” • “TEN” The above listed aural callouts are sounded by the EGPWS when the radio altitude associated with the callout is reached. In addition to these standardized callouts, aural notification of descent within one hundred feet (100’) of instrument approach minimum altitude and reaching approach minimum altitude will take place if the crew has manually entered the minimum altitude (MDA or DH). The callouts are “APPROACHING MINIMUMS” and “MINIMUMS” and are sounded only once during the approach. (Other aural notification options may be selected and programmed during system installation - monitor the callouts during self- test for verification). If altitude callouts are not desired, selecting the RAD ALT VOICE O/R switch on the O-RIDES panel (shown in Figure 9) will inhibit the annunciation of callouts. An aural notification of excessive bank angle is a standard option (others are available for operator customizing). The business airplane bank angle limits are set at forty degrees (40°) above 150 feet radio altitude. See Figure 16. Below 150 feet, the bank angle limit is proportionally decreased with altitude, down to ten degrees (10°) at thirty (30) feet. The feature is inhibited below five (5) feet of altitude. If the airplane exceeds the bank angle limit for altitude, an aural notification of “BANK ANGLE, BANK ANGLE” is heard. If the bank limit is exceeded, the airplane must return to a bank angle of thirty degrees (30°) or less to reset the excessive bank callout. G. Mode 7: Windshear Alerting: If the airplane encounters environmental conditions often associated with a windshear at lower altitudes, aural and visual caution and warning alerts OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 29 October 11/01 Revision 5 are provided to the crew by mode 7 of the EGPWS. The operating envelope for the windshear alert is shown in Figure 17. Windshear alerting is computed using inputs from air data sensors for pitot/ static information, and accelerometers for sensing forces on the airplane. The computer interfaces with the IRSs and DADCs for attitude and TAT information, and with discretes for flap position and nutcracker switch data. The computer generates windshear cautions and warnings that are communicated via ARINC 429 bus inputs to the Symbol Generators for display on the PFDs. Mode 7 is operable between ten (10) and fifteen hundred (1500) feet radio altitude during takeoff, approach or go-around. The Windshear Computer detects suddenly changing headwinds and tailwinds, excessive updrafts and downdrafts, and other factors indicating an impending microburst. Moderate conditions of increasing headwind and updraft that do not immediately hazard the airplane result in the aural message “CAUTION, WINDSHEAR” over cockpit speakers and interphone, and the amber text message WINDSHEAR displayed on the PFD. More severe conditions (decreasing headwinds and downdrafts) prompt windshear warnings. The aural warning “WINDSHEAR, WINDSHEAR, WINDSHEAR” is sounded, and the red text warning WINDSHEAR is displayed on the PFD. For both cautions and warnings, the aural message is repeated only once, but the text message on the PFD remains in view until the airplane exits the windshear conditions. The parameters that prompt the windshear cautions / warnings are adjusted as a function of available climb performance, flight path angle, airspeeds that significantly vary from normal takeoff / approach / go-around speeds, and unusual fluctuations in Static Air Temperature (SAT) often associated with microbursts. 4. Enhanced Mode Functions: With the ability to compare accurate airplane position from FMS / IRS / GPS systems with the terrain database stored within the computer, EGPWS is able to improve the function of the seven basic modes of operation and provide the flight crew with additional features. A. Envelope Modulation: EGPWS modifies the alert envelopes of some basic modes at specific geographical locations where there are terrain features that are known to cause nuisance alerts or to inhibit needed alerts. The alert envelope for basic modes 4 (unsafe terrain clearance), 5 (excessive glideslope deviation) and 6 (advisory callouts) is expanded at some locations that are known to require additional terrain clearance, while at other locations modes 1 (excessive descent rate), 2 (excessive terrain closure rate) and 4 (unsafe terrain clearance) are desensitized to avoid nuisance alerts generated by known non-hazardous terrain. B. Terrain Clearance Floor: In conjunction with the Terrain Awareness Display (TAD), the Terrain Clearance Floor (TCF) function alerts the flight crew at any time the airplane descends below the TCF defined altitude regardless of airplane configuration. The alert envelope is depicted in Figure 18. A descent below the TCF will trigger the aural alert “TOO LOW TERRAIN” and the amber text message TERRAIN on the PFD. This feature is operational at all times OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 30 October 11/01 Revision 5 unless the TAD is inhibited. The floor is defined as seven hundred feet (700’) above terrain for all areas except within fifteen (15) miles of airport with a runway of 3500 feet or longer that is in the EGPWS database. As the airplane approaches a database airport, the floor drops to four hundred feet (400’) between twelve (12) miles and four (4) miles of the center of the runway. On airplanes with EGPWS software version -210 -210 and higher (SN 1426 and subsequent), the inner alert floor is lowered to two hundred forty-five feet (245’) and positioned closer to the center of the runway (typically 1/3 NM to 1 NM) due to the higher resolution of airplane position relative to the terrain database. For SN 1426 and subsequent, this software version also provides an identification logic that determines the most likely destination runway based on airplane position and navigation information. C. Runway Clearance Floor: The Runway Clearance Floor (RCF) is very similar to the TCF, and is available on -210 -210 software (SN 1426 and subsequent) equipped airplanes. The RCF uses a computed Geometric Altitude (see the description of Geometric Altitude in the following sections) in lieu of radio altitude. RCF provides improved terrain alerting in locations where the runway is located at a much higher altitude than the surrounding terrain, or where an approach to the runway transits a steep decrease in terrain clearance. If the airplane enters the RCF alert envelope, an aural “TOO LOW TERRAIN” alert is sounded and the amber TERRAIN text message is displayed on the PFD. The aural alert is not repeated unless there is a further twenty percent (20%) decrease in terrain clearance. The amber TERRAIN text message remains displayed on the PFD until the RCF alert envelope is exited. D. Look Ahead Terrain Alerting: The EGPWS is able to anticipate potential hazards to the airplane by using the terrain database and algorithms based on airplane position, flight path vertical component (climb or descent), and airplane track and speed relative to the terrain database. See Figure 19. The EGPWS projects a terrain alert envelope ahead of the airplane, above and below the projected flight path and laterally within ¼ mile and out to within ± three degrees (3°) of track (or more if the airplane is turning). If the system algorithms predict that the airplane will encounter hazardous terrain within sixty (60) seconds, an aural “TERRAIN, TERRAIN” caution is sounded and the amber TERRAIN text message is displayed on the PFD. The aural caution is repeated every seven (7) seconds while the airplane is in the caution alert envelope, and the text TERRAIN remains displayed until the airplane clears the terrain caution envelope. If the airplane is projected to encounter a terrain hazard within thirty (30) seconds, an aural “TERRAIN, TERRAIN” followed by a “PULL UP, PULL UP” warning is sounded, and a red text message PULL UP is displayed on the PFD. The aural warnings are repeated continuously and the red PULL UP is displayed until the airplane exits the terrain warning alert envelope. E. Terrain Awareness Display (TAD): The Terrain Awareness Display (TAD) is graphic representation of the terrain within two thousand feet (2000’) above or below the airplane, usually selected to the NAV / RADAR cockpit EFIS display by the EGPWS options on the Display Controller. (The TAD may be selected for view on OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 31 October 11/01 Revision 5 the PFD, in which case the display is similar to the weather radar display mode in HSI format.) The terrain display defined altitudes are shown in Figure 20. The TAD as it appears on cockpit EFIS displays is seen in Figure 21. This display will automatically appear on the NAV display if a terrain conflict is detected. The automatic display function is initiated by the EGPWS computer that switches the Display Controller to the TAD mode. If desired by the crew, the automatic TAD function may be inhibited with the TERR INHIB switch on the O-RIDES panel located on the center pedestal. CAUTION THE TERRAIN AWARENESS DISPLAY (TAD) IS INTENDED FOR USE ONLY AS AN ADVISORY OF POTENTIALLY THREATENING TERRAIN AHEAD. IN NO WAY SHOULD THE FLIGHT CREW USE THE DISPLAY FOR NAVIGATION OF THE AIRPLANE OR FOR GUIDANCE IN STEERING THE AIRPLANE CLEAR OF TERRAIN. The TAD offers a plan view image of surrounding terrain in patterns of green, yellow and red in varying densities. Each specific color and intensity represents terrain and / or obstacles above, level with or below the airplane’s altitude based upon airplane position relative to the geographic database. If the airplane is in an area not covered by the database (typically near the poles) the display is low density magenta. Terrain that is more than two thousand feet (2000’) below the airplane is not displayed, nor is terrain within four hundred vertical feet (400’) of the elevation of the nearest airport runway. See the table at the end of this topic for a full description of the significance of the colors and densities of the TAD function. With the incorporation of the Peaks function, the TAD presents a digital readout of the elevations of the highest and lowest terrain and / or obstacle currently displayed. The numerical values of the readout are in hundreds of feet above mean sea level (MSL), thus a display of 125 equals (=) 12,500 feet MSL. The elevation values are displayed in the same color as the terrain of that elevation. The elevation of the highest terrain indicated in red, the lowest in green. If there is no significant variation in terrain elevation, for instance over flat terrain, only the highest elevation is indicated numerically. The numerical elevation values are no longer displayed when the airplane is five hundred feet (500’) or less above the terrain (250’ if the landing gear is extended). When the image is initially presented, the ten (10) mile range is the default value - other range values must be manually selected. When potential terrain conflicts prompt caution or warning alerts, the terrain and / or obstacle is depicted in solid yellow for cautions and solid red for warnings. Additionally, during alerts the image scale of the area immediately surrounding the hazard is enlarged to better identify a small obstacle or terrain feature. OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 32 October 11/01 Revision 5 Color Indication Solid Red Terrain / Obstacle Threat Area - Warning Solid Yellow Terrain / Obstacle Threat Area - Caution 50 % Red Fill Terrain / Obstacle that is more than 2000 feet above airplane altitude 50 % Yellow Fill Terrain / Obstacle that is between 1000 feet and 2000 feet above airplane altitude 25 % Yellow Fill Terrain / Obstacle that is 500 feet (250 feet with landing gear extended) below to 1000 feet above airplane altitude Solid Green (Peaks display) Shown only when no Red or Yellow Terrain / Obstacles are within range of the display. The highest Terrain / Obstacle is not within 500 feet (250 feet with landing gear extended) of airplane altitude 50 % Green Fill Terrain / Obstacle that is between 500 feet (250 feet with landing gear extended) and 1000 feet below airplane altitude 50 % Green Fill (Peaks display) Terrain / Obstacle that is in the middle elevation band when there is no Red or Yellow Terrain / Obstacle within range on the display 16 % Green Fill Terrain / Obstacle that is between 1000 feet an 2000 feet below airplane altitude 16 % Green Fill (Peaks display) Terrain / Obstacle that is in the lower elevation band when there is no Red or Yellow Terrain / Obstacle within range on the display Black No significant Terrain / Obstacle 16 % Cyan Fill (Peaks display) Water at mean sea level elevation (0 feet MSL) Magenta Fill Unknown terrain. No terrain data in the database for the magenta area shown F. Geographic Altitude: The alerts and displays generated by the EGPWS are most accurate when airplane altitude can be determined with a high degree of certainty. To obtain the highest accuracy in measuring airplane altitude, the EGPWS computes a Geographic Altitude (GA). GA is a blended altitude derived from all altimeter data sources available, and includes: • Non-corrected standard altitude • Runway calibrated altitude computed during takeoff • GPS calibrated altitude • Radio altitude calibrated during approach • Barometric altitude, corrected for local conditions if available For each of these readings, a Vertical Figure of Merit (VFOM) is determined in order to calculate the importance of the individual reading in blending the final GA computation. The final computed GA value is more accurate than the value of individual sensor readings and allows a more OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 33 October 11/01 Revision 5 precise determination of separation between the airplane and the terrain in the EGPWS database. NOTE: A terrain awareness display with degraded accuracy remains available if radio altitude information is lost. A GA is formulated from the available altitude data sources for computing the terrain display. A display generated without radio altitude should be used only as a general cue for terrain awareness, and should not be relied upon for navigational purposes. 5. Controls and Indications: A. Circuit Breakers (CBs): Circuit Breaker Name: CB Panel: Location: Power Source: EGPWS AC CPO D-10 L MAIN 115V AV φC EGPWS DC CPO E-10 L MAIN 28V DC B. Advisory (Blue) CAS Messages: CAS Message: Cause of Meaning: GPWS FAIL Ground Proximity Warning System (GPWS) has failed. WINDSHEAR FAIL Failure of essential input data from one or more of the following: AOA, Stall Warning System or IRS accelerometers. TERRAIN INHIBITED Terrain inhibit switch selected ON. TERRAIN NOT AVAIL Airplane position cannot be determined due to failure / malfunction in GPS and / or IRS systems. C. System Test: The GPWS switch on the TEST panel, located on the cockpit center console (location varies) initiates an EGPWS system self-test. Prior to initiating a self-test, determine that the following conditions are met: • Normal airplane power is available and EGPWS is ON • No O-RIDE switches are selected (TERR INHIB, RAD ALT VOICE O/R or GPWS VOICE O/R) • No GPWS inoperative annunciations are displayed on CAS Pressing the GPWS TEST switch will result in the following indications if the system is functioning normally: • CAS messages GPWS FAIL, WINDSHEAR FAIL, TERRAIN INHIBITED and TERRAIN NOT AVAIL displayed • Amber caution light BELOW G/S on • “GLIDESLOPE” annunciation over cockpit speakers and interphone • Amber BELOW G/S light extinguishes • Blue G/S INHIBIT light on • Blue G/S INHIBIT light extinguishes • Red PULL UP text warning displayed on PFD • “PULL UP” aural annunciation over cockpit speakers and interphone OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 34 October 11/01 Revision 5 • Red PULL UP text warning clears • Red WINDSHEAR text warning displayed on PFD • “WINDSHEAR, WINDSHEAR, WINDSHEAR” aural annunciation over cockpit speakers and interphone • Red WINDSHEAR text warning clears • Amber WINDSHEAR text caution displayed on PFD • Amber WINDSHEAR text caution clears • Red PULL UP text warning displayed on PFD • “TERRAIN, TERRAIN” aural warning followed by “PULL UP, PULL UP” aural warning annunciated over cockpit speakers and interphone • Terrain test pattern shown on cockpit displays • Red PULL UP text warning clears • CAS messages GPWS FAIL, WINDSHEAR FAIL, TERRAIN INHIBITED and TERRAIN NOT AVAIL clear • Terrain test pattern clears on cockpit displays 6. Limitations: A. Flight Manual Limitations: (1) Pilot’s Manuals: The Honeywell Enhanced Ground Proximity Warning System Pilot’s Guide, Publication Number 060-4241-000, Revision D, dated March 2000 (or later approved revision appropriate to the software version below) shall be immediately available to the pilots for -208 -208 (SN 1390 through 1425) or -210 -210 (SN 1426 and subsequent). (2) Clearance: Pilots are authorized to deviate from their current Air Traffic Control (ATC) clearance to the extent necessary to comply with an EGPWS warning. (3) Navigation: Navigation is not to be predicated upon the use of the Terrain Display. (4) Database: The EGPWS database, displays and alerting algorithms currently account for man-made obstructions. (5) Terrain Display: The Terrain Display is intended to serve as a situational awareness tool only, and may not provide the accuracy and / or fidelity on which to solely base terrain avoidance maneuvering. Terrain Display shall be selected OFF when within 15 NM of landing at an airport when: • The airport has no published instrument approach procedure (-104 -104 software version only). • The longest runway is less than 3500 ft in length. • The airport is not in the EGPWS database. OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 35 October 11/01 Revision 5 (6) TAWS: The production EGPWS installation meets the requirements for Class A TAWS as defined in Advisory Circular AC 25-23. 7. System Notes: The EGPWS database consists of three (3) smaller databases: • Terrain database that covers most of the earth • Obstacles database that covers all charted obstacles in North America and slightly beyond • Runway database that covers all runways at least 3,500 feet in length The database is updated when significant changes occur. The database updates are on a PCMCIA card available from Honeywell. The number of the latest database version is listed on the Honeywell website http://www.egpws.com/ or by calling the EGPWS hotline at (800) 813-2099. OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 36 October 11/01 Revision 5 EGPWS System Diagram Figure 8 OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 37 October 11/01 Revision 5 OPERATING MANUAL THIS PAGE IS INTENTIONALLY LEFT BLANK. PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 38 October 11/01 O-RIDES / TEST Panels on Center Pedestal Figure 9 OPERATING MANUAL 2A-34-00 Page 39 / 40 October 11/01 Excessive Descent Rate Envelope - Mode 1 Figure 10 OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 41 October 11/01 Revision 5 Excessive Terrain Closure Envelope - Mode 2A Figure 11 OPERATING MANUAL PRODUCTION AIRCRAFT SYSTEMS 2A-34-00 Page 42 October 11/01 Revision 5