APU Flashcards
Max EGT limits for Start
800F for 1 min, then up to 1200 F
Max EGT limits for GEN ONLY
decreases from 1200 F to 800 F
Max EGT limits for EWO
1300 F
APU RPM for normal, GEN ONLY, and EWO modes is approx _____
100 – 103%
When checking the FIRE system on the APU you should see the ________ light come on then the ________ light to know that the system check’s good
DSBLD, FIRE
The APU DRS OPN light will go out _______ after you select STOP and you should check that it goes out within _____
30 sec; 1 min
You cannot restart an APU for ____ or ________ indications but you are allowed ___ restart for transient BITE codes
Fire or overheat; 1
T/F Once an ESCU has initiated a shutdown or start, it cannot be manually interrupted by normal controls until the sequence is complete
TRUE
To ensure the APU doors are not frozen shut when OAT is below 4C and visible moisture is present, ___________________________ prior to starting the APUs
Open and close the APU doors manually
Automatic stopping of the APU may indicate a _______ or
Fire or overheat within the unit
APU Start Accumulator Pressure is _________
3,000 +/- 350 PSI
EWO mode should only be used ____
When authorized by the proper authority
To place both APUs in EWO mode press the ______ switch
EWO
If the emergency dictates, the APU’s may be shut down by pressing the ____.
APU DISENG switch
Do not operate the air conditioning system with the right alternate pressurization switch in _____ for an extended period of time
Full increase
The Ready light will come on if the APU is operating in either the ________ or ________ mode
Normal or EWO
You have just arrived at the aircraft and you see the DRS OPEN and RDY light illuminated. This indicates the APUs
Have reached 100% in the Normal mode
The APU HYD accumulators are pressurized by
the Right HYD system or the Left after Crossover
Check the APU enclosure floor for evidence of fuel or HYD fluid prior to a _____ start
Normal
With the APU Generator Switch in the GEN TEST, check the ACTIVE GENERATOR lights to determine______
Which APU has the generator installed
If APU surge bleed pulsing occurs after the RDY light comes on___.
Shut down the APUs
Bleed air from the APUs cannot reach the air conditioning pack if the ____ is not open
Crossover Valve
Be sure the ram air inlet scoop and outlet ducts are open and clear before ________ the airplane with the APUs
Heating
The APU fire detector system remains energized for ____ minutes after the APU’s are shut down
5 minutes
Manual charging of the APU Start Accumulators requires approximately _____ full pump strokes to complete recharging
500
