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Flashcards in APU Deck (11)
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1

What causes an automatic EMER. SHUTDOWN of the APU? When is this facility available?

- APU fire on the ground.
- Pressing the APU fire on the exterior panel.
- APU fire pb is pushed.
Flight phases 1-2, 6, 9-10

2

Why would the APU continue to run after being selected OFF?

If using APU bleed air, the APU keeps running for cooling period of 60-120 secs.

3

What happens if excessive EGT is sensed?

Amber fault light and a caution appears on ECAM. This is followed by an automatic shutdown.

4

AUTO (EMER) SHUTDOWN is available during which phases of flight?

Auto shutdown is available during all phases of flight.

5

What causes the FLAP to OPEN?

What does the message FLAP OPEN mean exactly?

- When MASTER SW p/b is pressed.
- In green when APU air intake flap is fully open.
- ECAM Advisory 3min APU has been switched OFF if flap still not fully closed.

6

What happens if the START button is pressed immediately after the MASTER button is pressed?

Nothing. The start switch is only energised when the flap has fully opened.

7

What is the Maximum altitude for APU start?

- 41,000’ by electrical power [normal operation]
- 25,000’ by battery only

8

What are the altitude limitations for the use of APU bleed & packs?

2 packs: 15,000’
1 pack: 22,500’ / 20,000 [MSN-dependant]

9

What would you do if the SD showed LO OIL LVL?

- The APU may be started and operated even if the LOW OIL LEVEL ECAM advisory is displayed.
- Maintenance action is required within 10hrs of APU operation.

10

What is the APU start attempt limitation?

After 3 consecutive APU start attempts, the flight crew must wait 60min before a new start attempt.

11

"Available" on the APU start switch means what?

- Once N > predetermined threshold (around 95%) [MSN-dependant]
- APU can now be used for electrics and/or bleed