APU 1
This aircraft auxiliary equipment supplies only bleed air.
What is a Ground Turbine Compressor?
The aircraft must battery must be ______ for APU operation.
What is on?
A GTC supplies only pneumatic power an APU supplies pneumatic and electric power.
What is the difference between a GTC and an APU?
Turboshaft.
What type of engine is the APU?
Usually in the tailcone.
Where are most APUs located?
Only this part of the aircraft requires a CSD to maintain 400 hertz.
What are the main engines?
Frequently is identical to the engine driven generators.
What is the APU generator?
This is where the APU gets its oil supply.
What is from its own system?
When the bleed valve is open.
What is most of the load on an APU occurs?
Remains at or near rated speed regardless of the load condition
What is an APU in operation?
This is used to rotate the APU during start.
What is an electric starter motor?
This is where the APU gets its fuel.
What is the aircraft main fuel supply?
On APU's equipped with a free turbine and load compressor used is to
What is provide bleed air for aircraft pneumatic systems?
Upper is an inlet for the oil cooler and lower is the exhaust duct.
What is the Boeing 737-NG 2 holes in the tail?
Emergency shutdown only.
What can be done at the APU ground accessible panel?
The APU uses its _______ system for fire protection.
What is its own?
This controls APU fuel scheduling during start and operation.
What is the APU fuel controller?
3 consecutive starts or attempts within 60 minutes with a 5 minute cool-down between each attempt.
What is how many consecutive starts may be attempted on an APU?
stabilize the pressure of the air before it enters the compressor.
What is the function of an APU air inlet plenum?
Only if a fire condition is present.
When the fire shutdown switch be used?
The APU can be used in _______ to supply electric and pneumatic power if an engine fails.
What is flight?
This aircraft uses a time delay for APU shutdown.
What is the Boeing 757?
Pneumatic loading will be automatically modulated to maintain a safe EGT.
What is when maximum APU shaft output power is being used in conjunction with pneumatic power.
APU will shut down without any delay.
What will happen if the APU selector switch is turned off when the bleed valve has been closed for 60 seconds or more?
This provides APU cooling prior to shutdown.
What is closing the bleed vavle?