- The 700/800/900 APU generator will supply both Transfer buses in flight
TRUE
- What electrical power source is required for starting the APU?
Aircraft battery
- What is the fuel source for starting the APU with only aircraft battery power available? (COLD aircraft)
1 fuel tank
- A 737-800 aircraft is in-flight with APU running. Turning OFF the aircraft BATTERY switch will
Cause the APU to shut down
- What are the initial indications when the APU is starting?
LOW OIL PRESSURE light one, full scale negative amps indication on DC ammeter BAT position
- The New Generation 737 APU generator can be used to supply both Transfer Buses up to what maximum altitude?
41,000 feet if no APU bleed air is used
- What does an illuminated APU MAINT light indicate?
Oil quantity is insufficient for extended operation
- 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
- What indicates the APU generator is ready for use?
When the blue APU GEN OFF BUS light illuminates
- What is the normal procedure for using APU bleed air after starting the APU?
APU bleed air switch may be turned ON after one full minute of APU operation
- What causes an automatic shutdown of the APU?
Fire warning
- What causes an automatic shutdown of the APU in flight?
BAT switch placed to OFF
- Which of the following causes an automatic shutdown of the APU in flight or on the ground?
Fire warning
- 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, place APU switch to OFF, wait 120 seconds, then battery switch OFF
- Which of the following set of conditions causes the APU OVERSPEED light to illuminate?
All answers are correct: APU start abort, APU speed sensing failed-APU shuts down, APU rpm limit exceeded
- A normal APU start cycle can take as long as:
120 seconds
- Inflight, with one engine generator inoperative, the APU can supply electrical power to:
both buses up to 41,000 feet
- A 737-700 aircraft is parked with APU running. Turning the APU control switch to OFF __________.
All answers are correct: closes the APU bleed valve, trips the APU generator field relay, shuts down the APU after 60 sec
- An illuminated APU “GEN OFF BUS” light indicates:
The APU is at operating speed
- Turning the battery switch to OFF inflight, will cause the APU to shut down
TRUE
- Minimum battery voltage for APU start is:
23 volts
- APU starter engagement may first be observed by:
Full scale left deflection of DC ammeter with the BAT position selected
- After APU shutdown, the battery switch should remain on for 120 seconds after the APU switch has been placed to OFF.
TRUE
- What causes an APU OVERSPEED annunciator light to illuminate?
All of these answers are correct: APU rpm exceeds limits, APU auto start sequence is aborted, over speed shutdown protection is inop during APU shutdown
- An illuminated APU DET INOP light when no fire warning test is being performed:
Requires the APU to be shut down if operating because the detectors is inop
- After an inflight APU start, the APU will supply ___________.
Pneumatic load only up to 17,000 feet
- The maximum allowable EGT for the APU is ______.
There is none
- After aborting an APU start, how soon may another start be attempted?
After 3rd attempt 15 minutes
- Successful APU starts are not assured above ___________.
FL 250
- What is the primary function of the Main Engine Control?
Hydro-mechanical control of fuel
- What is the automatic function of the EEC during a climb?
Maintain initial N1 climb thrust throughout climb
- When is Engine speed commanded to LOW IDLE?
On the ground, four seconds after touchdown
- How is the main fuel shutoff valve at the engine pylon operated?
Electrical control by the engine start lever and fire switch
- A dim FUEL VALVE CLOSED light indicates?
Main fuel shutoff valve at the engine pylon is closed
- What does an illuminated fuel FILTER BYPASS light indicate?
Impending bypass of the engine fuel filter
- How is the HMU fuel shutoff valve operated? (This valve is at the engine fuel control)
Electrically by the engine fire warning switch and start lever
- What does the engine oil pressure indicator show?
Unregulated pressure as a function of N2 speed
- What is indicated when the OIL FILTER BYPASS light illuminates?
The scavenge oil filter is contaminated
- The engine oil temperature indicator shows oil temperature coming out of the engine after the oil cooler
TRUE
- During engine start, the start switch disengages at N2.
56%
- The _______shows the current mode of the N1 limit computed by the FMC.
Thrust Mode Annunciator
- The engine accessory components are driven by
The N2 spool
- With the engine at normal operating temperature and idle, the oil PRESSURE must be ___________.
Above the red radial
- Engine fan air cools _______.
The IDG/Generator
- With the engine at climb N1 limit power, the stage pneumatic bleed provides bleed air for the pneumatic system.
5th
- The power to move the engine thrust reversers is ______.
Hydraulic
- Engine oil is cooled by ___________.
Engine fuel flow
- Reverse thrust operation is permitted for
Ground use only
- What is maximum engine N1 limit?
104.0%
- What is maximum engine N2?
1 05.0%
- What is maximum takeoff EGT?
950 C
- What is maximum continuous engine EGT?
925C
- What is maximum starting EGT for the aircraft engines?
725C
- What is minimum oil pressure for continued engine operation?
13 psi
- An engine must be shut down if the oil temperature exceeds __________.
155C
- Which is the correct EEC switch configuration for takeoff?
Both must be ON or both ALT
- Condition: BAT Volts: 23V; BATT SW: ON; APU SW placed to START; no DC ammeter deflection is observed during a one minute period. What should the pilot do?
Place the APU switch to OFF, then try again
- What causes an automatic shutdown of the APU inflight?
LOW OIL PRESS light on
- The New Generation aircraft APU generator will power both transfer buses inflight.
a. True