APU Flashcards
1
Q
Purpose of APU (ground / take off / in flight)
A
On the ground:
- Bleed Air for engine start
- Air Con
- Power to electrical system [via its own generator
- Has own pneumatic supply
Take-off
- If optimum performance required - APU can be used for Air Con
In flight
- Backup for electrical system
- Bleed air for air con
- Assist engine starting
2
Q
Air Intake Flap key facts:
A
- Located bottom of tailcone
- Electrically operated
- Ducts external air to the compressor inlet
- “Flap open” displayed on ECAM APU page
3
Q
How is Fuel flow provided for the APU?
A
- Normally from left side fuel system
- If unavailable, APU pump will start automatically
4
Q
APU oil
A
Complicated! Basic - uses its own independent integral lubrication system (for lubrication and cooling)
5
Q
APU Bleed System. How is it engaged and what is it used for?
A
- Engaged by APU BLEED pb
- provides bleed air for:
a) engine start
b) air con
c) pressurisation (pneumatics) - It has priority over engine bleed air
6
Q
What is the ECB and what does it do?
A
Electronic Control Box
- Controls and Monitors all modes of APU operation includinga) start
b) speed
c) Temp
d) shut down (auto and normal)
7
Q
Where is the smoke detector in the avionics bay?
A
Downwind of the avionics compartment