Auxiliary Power Unit Flashcards
What type of APU is on the P-8A?
Allied signal 131-9(B) gas turbine engine
Where is the APU located?
A fireproof compartment in the tail
What two types of power does the APU provide?
Electrical
Pneumatic
How many fire bottles does the APU have?
One
Where is the APU fire bottles located?
Horizontal stabilizer accessory compartment
What is the purpose of the DC boost pump?
Supplies fuel to the APU using standby power during startup
What is required before startup of the APU?
Operator must check the ADB for power status, must do a walk around to inspect the current conditions of aircraft tie downs, APU intake/exhaust and ram air intakes
During the APU start cycle, the APU EGT indication may fluctuate between what temperatures prior to normal EGT rise?
0-1100 degrees Celsius
What conditions cause APU to shut itself down?
- Over speed (116%)
- APU compartment fire
- Low oil
How can you check APU oil levels?
- CDU
- Sight glass on APU
What are the APU oil readings?
Full: 5.7qts
Add: 4.3qts
Low: 3.8qts
What type is oil is used for the APU?
MIL-PRF-23699
What controls and monitors the APU?
Electronic Control Unit (ECU)
What information about the APU can be found in the ADB?
- Type of APU
- Maintenance done to the unit
What occurs when the battery switch is moved to the OFF position during the APU operation?
The APU will immediately shut down and the APU fault light will illuminate
