A320 APU Limitations

Question 1

APU START

Answer 1

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

Question 2

ROTOR SPEED

Answer 2

107%

Question 3

Maximum EGT for APU start (below 35 000 ft)

Answer 3

1 090 °C

Question 4

Maximum EGT for APU start (above 35 000 ft)

Answer 4

1 120 °C

Question 5

Maximum EGT for APU running.

Answer 5

675 °C

Question 6

Max altitude to assist engine start

Answer 6

20 000 ft

Question 7

Max altitude for air conditioning and pressurization (single pack operation)

Answer 7

22 500 ft

Question 8

Max altitude for air conditioning and pressurization (dual pack operation)

Answer 8

15 000 ft

Question 9

Use of APU bleed air for wing anti-ice is

Answer 9

not permitted.

Question 10

During refuel/defuel procedures, APU starts or shutdown are permitted with the following restrictions:

Answer 10

‐ If the APU failed to start or following an automatic APU shutdown, do not start the APU
‐ If a fuel spill occurs, perform a normal APU shutdown.