Engine apu.txt

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Engine apu.txt
2014-08-26 21:54:41

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  1. You are flying a -700/-800. During your initial climb out you notice that the EGT is rising toward redline. Will the EEC keep the EGT from exceeding the limit?
    Answer: No. The EGT limit must be observed by the crew because the EEC does not provide EGT redline exceedance protection.
  2. While starting a -300, you observe the EGT slowly climbing towards the start limit. If the EGT reaches or exceeds the start limit will the red warning light on the EGT gauge illuminate?
    Answer: No. This light will illuminate when the EGT limit of 930 C has been reached or exceeded, not when the start limit is exceeded. It will remain illuminated until EGT is reduced below the limit.
  3. 3. If the EGT reaches 728 degrees C, can you continue?
    Answer: No. If the start EGT limit exceeds 725 degrees C, it must be written up and cleared by maintenance.
  4. Your crew is originating a -700/-800 at a gate with no ground power. As you complete the Aircraft Preflight flow, how long must you wait to start the APU after placing the Battery Switch ON? Why? Does this consideration apply to a -300/500?
    Answer: Wait 60 seconds after turning on the battery before starting the APU to prevent nuisance computer faults. This does not apply to the -300/-500.
  5. If the APU failed to start on the first attempt how long would you wait before attempting another start? If the second attempt fails, can you try again? If so, how long must you wait?
    • Answer: Wait 90 seconds prior to second APU start attempt. A third try may be attempted after a five minute wait. Do not attempt a fourth start.
    • Reference: AOM Chapter 3
  6. 6. You are at the gate, with no ground power, getting ready to start up your -700/-800. The APU is started (using the battery). The APU GEN OFF BUS light is illuminated but the APU voltage and frequencies indicate zero. Is this a normal indication?
    Answer: Yes, when the APU is started using battery power only, there is no indication on the electrical metering panel that the APU generator has come online and is ready to be selected. Both the frequency and voltage readings are zero until the APU generator is placed on line. The blue APU Gen Bus OFF light will be illuminated; the light indicates good power is available.
  7. 7. The blue MAINT light is illuminated on the APU panel. Should you continue to operate the APU?
    • Answer: Yes. The common reason for this light is low oil quantity. Notify maintenance at the earliest opportunity.
    • Referen
  8. 8. While at the gate the Flight Attendants report that the gate services preconditioned airflow is minimal and not keeping the cabin temperature comfortable. Can you supplement the preconditioned air with an air conditioning pack using the APU bleed? Why? How would you fix this problem?
    • Answer: No. The AOM does not allow the use of preconditioned air and a pack at the same time
    • If gate services are not properly cooling the aircraft, restart the APU and report the issue via an Irregularity Report.
    • Reference: A
  9. 9. How soon after start may the APU be used as bleed air source? In a -300/-500 aircraft how long must you wait to shut down the APU after selecting the APU bleed air switch off? How long for a -700/-800? Why is there a difference?
    • Answer: The APU should be operated for one minute before being used as a bleed air source. In the Classic Fleet the APU bleed air switch should be off for at least two minutes to allow for cooling before the APU is shut down. The -700/-800 APU may be shut down as soon as the bleed air switch is selected off. This is because the -700/-800 has built in cooling circuitry that will shut down the APU when it is cool.
    • Reference: AOM
  10. 10. During engine start in the -700/-800 you raise the start lever, but forget to hack the clock or note the time. The engine shows no EGT rise, and after a while, you abort the start. What has most likely happened? Does the EEC give you any protection? When should we abort the start with no EGT rise, anyway?
    Answer: A wet start occurs if the EGT does not rise after the start lever is moved to IDLE. If a wet start is detected, the EEC turns off the ignition and shuts off fuel to the engine 15 seconds after the start lever is moved to IDLE. The pilot should abort the start for no EGT rise10 seconds after the start lever is raised to idle (30 seconds for inflight start).
  11. 11. During a night landing at BUR, the pilot flying, anxious to stop the aircraft quickly, actuates reverse thrust about 5 feet in the air. Will the reversers deploy? Why?
    • Answer: Yes. The thrust reverser can be deployed inflight when either radio altimeter senses less than 10 feet altitude, or when the air/ground safety sensor is in the ground mode. An interlock mechanism restricts movement of the reverse thrust lever until the reverser sleeves have approached the deployed position. (Approximately 60% deployed)
    • Reference: FRM Chapter 7
  12. 12. It is your first engine start of the day in your -700/-800. As the engine start progresses, the white box surrounding the EGT readout starts flashing. What is happening? Despite your best efforts to abort the start quickly, the EGT exceeds the start limit. What other protections does the -700/-800 provide?
    • Answer: The white box surrounding the EGT read out flashes to warn of an impending hot start or engine stall. Current versions of EEC software automatically turn off the ignition and shut off fuel to the engine. If the start limit is exceeded, the EGT display (both box and dial), turn red. After the EGT decreases below the start limit, the box turns white. After shutdown of both engines, the EGT box on the affected engine turns red to remind the crew of the exceedance.
    • Reference: AOM Chapter 3, F
  13. 13. It is a cold morning in MSP for first flight of day. During engine start the OIL FILTER BYPASS light illuminates. What do you do?
    • Answer: If the filter bypass light is accompanied by abnormally high oil pressure, continue to operate engine at idle until oil pressure returns to normal. The filter bypass light should extinguish as oil warms.
    • Reference: A
  14. 14. Shortly after takeoff in your -700/-800, you notice the left engine oil quantity is reverse video and LO (white) is next to the quantity. Are you losing your oil?
    • Answer: Probably not. Video is reversed and LO (white) displayed for low oil quantity.
    • Indicated oil quantity may decrease significantly during engine start, takeoff and climb out. This is a common occurrence Boeing calls “oil gulping.” If the oil quantity stabilizes (even at a low level), and the oil temperature and pressure remain normal, you most likely do not have a problem. Continue to monitor the quantity, temperature and pressure.
    • Reference: FRM Chapter 7
  15. 15. When operating in moderate or heavy rain, what must you do with the engine start switches? What does this accomplish?
    Answer: When operating in, or in the vicinity of, moderate to heavy rain, hail, or sleet, select both engine start switches to FLT. The ignition select switch is bypassed and both igniters are energized.
  16. 16. During climb the Flight Crew notices #2 engine oil quantity has dropped to 40%. Should the oil be serviced upon arrival at their destination?
    • Answer: Oil quantities requiring service are based on fight deck quantity indicator readings within 30 minutes of engine shutdown.
    • Reference: AOM Chapter 3 and FRM Chapter 7
  17. 17. As you are climbing out in a -700/-800 you encounter moderate turbulence and heavy rain. If the engine flamed out, what would occur?
    Answer: The -700/-800 provides auto-relight capability for flameout protection. Whenever the EEC detects an engine flameout, both igniters are activated even if the Start Selector Switch is in OFF. A flameout is detected when an uncommanded rapid decrease in N2 occurs, or N2 is below idle RPM.
  18. 18. You are cruising at FL 410 (-700/-800), or FL 350 (-300) when your number one engine flames out. Besides figuring where the nearest suitable airfield is, what considerations are there for drift down, starting the engine and APU? If the engine restarts, should you proceed to your destination?
    • Answer: First-Maintain Aircraft Control, Analyze the Problem, Take the Appropriate Action, and Maintain Situational Awareness.
    • Tell ATC of your situation and intentions, follow the drift down procedures in the Non-Normal Maneuvers/Profiles section of the QRH, then refer to the Engine Failure/Shutdown Checklist, which will keep you from rushing the restart until you are in the start envelope. In accordance with the QRH, you may start and operate the APU immediately. Providing there is no fire or apparent engine damage, restart the engine with the In-flight Engine Start Checklist, waiting until you are in the windmill or starter assist envelope.
    • FARs require that you land at the nearest suitable airport in point of time at which a safe landing can be made. Subsequently restarting the engine does not delete this requirement.
    • Reference: FOM
  19. 19. After a normal landing in the -700/-800, while taxiing in, the MASTER CAUTION light illuminates due to the #1 ENGINE CONTROL light, but you quickly cancel it without checking the source. After gate arrival and engine shutdown you investigate the reason for the master caution but cannot find anything out of the ordinary. When would the engine control light illuminate again and why? Could you take off?
    • Answer: The ENGINE CONTROL light would illuminate after engine start. This light indicates that there are non-deferrable faults in the engine control system. This light only functions when the aircraft is on the ground and the engine is running.
    • Reference
  20. 20. You are in a -700/-800 and start the APU at the gate on an originating flight. You note that during the start, the EGT had some significant fluctuations and even pegged once at 1100 degrees. The APU Low Oil Pressure Light also blinked on and off several times during the start. However, the APU did start and now has normal indications, is it OK for use?
    • Answer: Yes. During the -700/-800 APU start cycle, the APU EGT indication may fluctuate from 0 degrees to 1100 degrees C prior to normal EGT rise and the LOW OIL PRESSURE light may cycle on and off several times. These indications have no adverse effect on starting the APU. It is not necessary to monitor EGT during start.
    • Referen
  21. 21. During cruise flight the MASTER CAUTION and ENG annunciator lights illuminate. You look up and see that the #1 EEC white ON and amber ALTN lights are on. What has occurred and what can you expect?
    Answer: The EEC has changed into the soft alternate mode due to the loss of required signals or DEU failure (DEU failure will cause both EECs to change to soft alternate mode). The EEC will use its last known inputs and you should see little change in the engine parameters. When the thrust lever is pulled to idle, the EEC will enter the hard alternate mode, but the white ON light will remain illuminated. When the EEC switches are pushed (per QRH) the ON indication will extinguish. Both engines must be operated in the alternate mode.
  22. 22. What is the limitation for operating engines after engine start?
    Answer: Operate engines at or near idle, after rollback, for a minimum of 2 minutes prior to applying takeoff thrust.
  23. 23. What is the recommendation for the engines on the first flight of the day?
    Answer: On the first flight of the day, operate engines at or near idle, after rollback, for a minimum of 5 minutes prior to applying takeoff thrust.