APU Flashcards
Does APU have self-sealing fuel lines?
No
APU system provides what two powers/purpose?
Pneumatic (main engine starting and cabin heating) and electrical (ground operations and in flight emergency electrical power).
You can operate the aircraft without the APU but you risk:
Not being able to complete certain in flight Eps.
APU accumulator minimum pressure:
2800 PSI
Which fuel cell does the APU use?
1 fuel cell
APU oil reservoir contains how much oil?
3 qts
How is the APU generator cooled?
Air cooled
Limitation of APU Generator?
Cant power backup hydraulic pump and windshield anti ice at the same time. Backup hydraulic pump takes priority.
If the APU Generator Control Unit (GCU) detects an overload, the APU generator will:
Be taken off line and the APU GEN ON advisory light will extinguish.
What action is taken when APU OIL HOT caution appears?
APU shutdown immediately. After a 30 minute cooling period and oil level is okay, the APU may be restarted.
Electronic Sequencing Unit (ESU) will shut down the APU and provide a BIT code for any problems detected except:
APU OIIL HOT
If APU fails, you must do what before attempting another start?
Check APU BIT codes
The accumulator provides hydraulic pressure for driving the:
APU hydraulic starter
When AC power is applied to the aircraft, the backup pump will recharge the accumulator in:
90 seconds
If AC electrical power is not available, only the reserve fire bottle can be discharged and fire extinguishing capability will be lost to which engine?
2 engine
