APU

Question 1

Compressor and turbine type?

Answer 1

Single stage centrifugal compressor and Radial turbine.

Question 2

APU model

Answer 2

Garrett 150 (AA)

Question 3

What governs the APU

Answer 3

ECU

Question 4

APU takes fuel from which tank

Answer 4

Right tank

cross feed for left tank

Question 5

Amount of fuel nozzles

Answer 5

6

Question 6

How does the APU get its fuel

Answer 6

Right engine provides motive flow
or left engine if xfeed is open
If engines off then an elec boost pump

Question 7

APU oil storage

Answer 7

1.89L (2 US gal)

Question 8

What can the APU run

Answer 8

Aircon, Pressurisation, hydraulic reservoir

Question 9

What will the APU auto shut down for in flight?

Answer 9

overspeed

overvoltage

Question 10

APU temp limits for start

Answer 10

max 974’C to 50% max 10sec for start

yellow arc 732’C by 90%

Question 11

Duct leak light temp?

Answer 11

71’C (160’F)

Question 12

APU fuel burn rate

Answer 12

APU only 45 + 30% (58.5)
A+G = 53 + 30% (69.9)
A=B= 90 +30% (117)
Roughly 130lbs / hr with APU/gen/bleed

Question 13

APU operational altitudes

Answer 13

operates at all altitudes
only start bellow 20,000ft between 135-240kts
test button 10sec max hold or it will blow the extinguisher

Question 14

APU feeds which pack

Answer 14

Into the left pack first but can access both packs with cross bleed.

Question 15

Pack stands for ?

Answer 15

Pneumatic Air Condition Kit
or
Pneumatic Air Cycle Kit