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27 Cards in this Set

  • Front
  • Back
Describe the APU
Single stage impeller with 2 stage axial flow turbine

Provides pneumatic air and AC power

Controlled by its own FADEC

Contant speed
What kind of APU do we have
Sunstrand APS2300
What controls the APU
Dedicated FADEC
What battery is used for APU start
Batt 1-Fadec and EICAS
Batt 2-APU starter
What is the fuel source for the APU
Tank #2, RT. Tank
What fuel pump is used for APU start
Batt power only=DC Pump
AC power available-ACMP #2
RT engine running-Ejector pump #2
Will the APU automatically shutdown if speed and acceleration rate isn't reached in starting time cycle
What does moving the APU start switch to OFF do
Starts the APU shutdown sequence with a 1 minute cool down period, Pneuatics shutdown immediately, and electric shutdown after a minute
Can the APU shutdown be cancelled
Yes by moving the the start switch back to on before the one minute cool down is up
What will automatically shutdown the APU on the ground
High EGT
High OIL temp
Low OIL pressure
FADEC Critical Fault
FADEC Sensor Fault
What will automatically shutdown the APU in flight
Fadec Critical Fault
Can the APU be started after a critical fault
What are the three ways to turn off the APU
OFF Button
Does the APU have bleed priority on the ground
What battery does the APU starter use
Battery #2
What is the power output of the APU
40KVA 115V 400HZ 3 phase
When is the APU available after start
When it has reached 95% RPM + 3 seconds
What bus provides APU fire protection
DC ESS Bus 2
What bus provides APU fire detection
DC ESS BUS 1 & 2
What normally provides fuel to the APU when the engines are running
Engine primary ejector pump
What normally provides fuel to the APU when the engines are not running
#2 AC fuel pump
During an APU start what provides fuel to the APU
#2 main fuel tank and a dedicated DC fuel pump
What is the cool down period when the APU is selected to off
1 minute pneumatics are removed immediately and electric remains for the minute
Is it possible to feed the APU from the left wing tank
Yes through the cross feed valve
How long before the APU will shutdown with a fire detection on the ground
10 seconds
What would be observed on the flightdeck if the APU did an automatic shutdown on the ground for fire detection
The APU would autoshutdown after 10 seconds and the red bar would show in the EMER STOP. If no action is taken after one minute the red bar will go out and the APU fire ext. button will turn red
What does pushing the APU EMER STOP button
Closes the APU FUEL SHUTOFF VALVE and bypasses the 1 minute cooldown period