Card Set Information

2012-04-17 21:13:52
B737 engine apu systems

B737 engine apu systems
Show Answers:

  1. What electrical power source is required for starting the APU?
    Aircraft battery
  2. TRUE or FALSE

    The 700/800/900 APU generator will supply both Transfer buses in flight.
  3. What is the fuel source for starting the APU with only aircraft battery power available? (cold aircraft)
    #1 fuel tank
  4. A 737-800 aircraft is in-flight with APU running. Turning OFF the aircraft BATTERY switch will:
    Cause the APU to shutdown
  5. What are the initial indications when the APU is starting?
    LOW OIL PRESSURE light on, full scale negative amps indication on DC ammeter BAT position.
  6. The New Generation 737 APU generator can be used to supply both Transfer buses up to what maximum altitude?
    41,000 ft. if no APU bleed air is used.
  7. What does an illuminated APU MAINT light indicate?
    Oil quantity is insufficient for extended operation.
  8. What prevents the APU electrical and bleed air loads from increasing the EGT above acceptable levels?
    The APU bleed valve modulates toward the closed position.
  9. What indicates the APU generator is redy for use?
    When the blue APU GEN OFF BUS light illuminates.
  10. What is the normal procedure for using APU bleed air after starting the APU?
    APU bleed air switch amy be turned ON after one full minute of APU operation.
  11. What causes an automatic shutdown of the APU?
    Fire warning
  12. What causes an automatic shutdown of the APU in flight? (NG 700)
    BAT switch placed to OFF
  13. What causes an automatic shutdown of the APU in flight or on the ground?
    Fire warning
  14. Which sequence of events should be accomplished for normal shutdown of the APU when "securing" the airplane?
    Operate for one minute with no pneumatic load, then place APU and battery switches to OFF, wait 20 seconds, then battery switch OFF.
  15. What conditions will cause the APU OVERSPEED light to illuminate?
    • APU start aborted
    • APU speed sensing has failed and the APU is shutdown
    • APU rpm limit exceeded
  16. A normal APU start cycle can take as long as:
    135 seconds
  17. Inflight, with one engine generator inoperative, the APU can supply electrical power to: (300/500)
    One bus up to 35,000 ft.
  18. A 737-700 aircraft is parked with APU running. Turnning the APU control switch to OFF______.
    • Closes the APU bleed valve
    • Trips the APU generator field relay
    • Shuts down the APU after 60 seconds
  19. An illuminated APU "GEN OFF BUS" light indicates:
    The APU is at operating speed
  20. TRUE or FALSE

    Turning the battery switch to OFF inflight, will cause the APU to shutdown (300/500)
  21. Minimum battery voltage for APU start is:
    23 volts
  22. APU starter engagement may first be observed by:
    Full scale left deflection of DC ammeter with the BAT position selected.
  23. TRUE or FALSE

    After APU shutdown, the battery switch should remain on for 20 seconds after the APU switch has been placed to OFF.
  24. What causes an APU OVERSPEED annunciator light to illuminate?
    Overspeed shutdown protection is inoperative during APU shutdown

    APU automatic start sequence is aborted

    APU rpm exceeds limits
  25. An illuminated APU DET INOP light when no fire warning test is being performed:
    Requires the APU to be shutdown if operating because the detector is inop.
  26. After an inflight APU start, the APU will supply________. (300/500)
    Pneumatic load only up to 17,000 ft.
  27. The maximum allowable EGT for the APU is_____.(300/500)
    760 degrees C maximum, 700 degrees C max continuous
  28. After aborting an APU start, how soon may another start be attempted?
    After 4 minutes
  29. Successful APU starts are not assured above______.
  30. What is the primary function of the Main Engine Control?
    Hydro-mechanical control of fuel.
  31. What is the automatic function of the PMC during a climb?
    Maintain initial N1 climb thrust throughout climb.
  32. When is Engine speed commanded to LOW IDLE?
    On the ground, four seconds after touchdown.
  33. How is the main fuel shutoff valve at the engine pylon operated?
    Electrical control by the engine start lever and fire switch.
  34. A dim FUEL VALVE CLOSED light indicates?
    Main fuel shutoff valve at the engine pylon is closed.
  35. What does an illluminated fuel FILTER BYPASS light indicate?
    Impending bypass of the engine fuel filter.
  36. How is the Main Engine Control (MEC) fuel shutoff valve operated? (this valve is at the engine fuel control)
    Mechanically by the engine start lever.
  37. What does the engine oil pressure indicator show?
    Unregulated pressure as a fuction of N2 speed.
  38. What is indicated when the OIL FILTER BYPASS light illuminates?
    The scavenge oil filter is contaminated.
  39. TRUE or FALSE

    The engine oil temperature indicator shows oil temperature coming out of the engine prior to the oil cooler.
  40. During engine start, the start switch disengages at N2: (300/500)
  41. The_____shows the current mode of the N1 limit computed by the FMC.
    Thrust Mode Annunciator
  42. The engine accessory components are driven by:
    The N2 spool
  43. With the engine at normal operating temperature and idle, the oil PRESSURE must be______.
    Above the red radial
  44. Engine fan air cools______. (300/500)
    The CSD/Generator
  45. With the engine at climb N1 limit power, the_____ stage pneumatic bleed provides bleed air for the pneumatic system.
  46. The power to move the engine thrust reversers is _______.
  47. Engine oil is cooled by________.
    Engine fuel flow
  48. Reverse thrust operation is permitted for:
    Ground use only
  49. What is maximum engine N1 limit?
  50. What is maximun engine N2?
  51. What is the maximum takeoff EGT?
    930 C
  52. What is the maximum continuous engine EGT?
    895 C
  53. What is maximum starting EGT for the aircraft engines?
    725 C
  54. What is minimum oil pressure for continued engine operation?
    13 psi
  55. An engine must be shutdown if the oil temperature exceeds_____.
    165 C
  56. What is the correct PMC switch configuration for takeoff?
    Both must be ON or both INOP (OFF)