APU

Question 1

APU Start

Answer 1

1-2-3-60’

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

Question 2

APU Inflight Start Attempt

Answer 2

When an APU inflight start attempt is required by maintenance, the following points apply:
An inflight start attempt is considered successful if:
1. The APU starts within 3 attempts.
2. The APU runs for 5 minutes after the AVAIL indication appears on ECAM.

Note: If the initial APU start attempt fails, it may be possible to facilitate an APU start, by waiting three minutes from the moment at which the APU MASTER SW pushbutton is set to ON before setting the APU START pushbutton to ON.

Question 3

APU Rotor Speed: Maximum N Speed

Answer 3

107%

Question 4

Maximum APU EGT

Answer 4

For APU start: 1,250 degrees Celsius

For APU running: 650 degrees Celsius

Question 5

APU Start/Shutdown During Refueling/Defueling

Answer 5

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

• 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.

Question 6

Maximum Altitude To Use APU’s Electrical Power

Answer 6

41,450 feet

Question 7

APU Battery Restart Limit Altitude (ELEC EMER CONFIG)

Answer 7

25,000 feet

Question 8

APU Bleed Air: Max Altitude For Air Conditioning And Pressurization (Single Pack Operation)

Answer 8

22,500 feet

Question 9

APU Bleed Air: Max Altitude To Assist Engine Start

Answer 9

20,000 feet

Question 10

APU Bleed Air: Max altitude for air conditioning and pressurization (dual pack operation)

Answer 10

17,500 feet

Question 11

APU Bleed Air: For Wing Anti-Ice

Answer 11

Not permitted

Question 12

APU Ground Starting And Operating Limit Altitude

Answer 12

14,600 feet