7 - Engines, APU Flashcards
Can you start and operate the APU with the blue MAINT light on?
Yes if needed.
After putting the APU switch to off, how long before the APU shuts down. Why?
60 seconds. To cool down.
Until what altitude can the APU supply only bleed air?
17,000 feet
Until what altitude can the APU supply both bleed air and electrical power?
10,000 feet
What happens to the APU if all electrical power is lost (including battery to off)
It will shut down without a cooling cycle
After the APU is started, how long do you have to wait before using it as a bleed air source?
1 minute
After the APU has shut down, can you turn off the battery straight away?
It is recommended to wait an additional 20 seconds for the inlet door to close
During engine start, when should you put the start lever to cutoff if you don’t get an EGT rise
10 seconds after selecting idle
Automatically 15 seconds
Before engine start, which engine indications are visible?
N1, N2, Oil Quant, Eng Vibration
Starting the APU draws electrical power from where?
With AC power, from Transfer bus 1, or battery power
What is the engine type used
CFM 56-7
If you have an impending hot start, when does the flashing white box reset?
Start lever to cut-off, or N2 stable
When you start the APU, if the APU GEN OFF BUS light does not illuminate, what indication will you get instead.
FAULT light, and auto-shut down
The APU starter cycle, may take how long?
120 seconds
What are the indication when the engine starter disengages
Starter switch automatically turns to off. Engine bleed valve (with indication) closes.
