APU

Question 1

Can the APU be started and operated even if the LOW OIL LEVEL ECAM advisory is displayed?

Answer 1

Yes. If there is no oil leak, then the remaining oil quantity allows normal APU operation for about 10 hours. (Ref: ECAM Advisory conditions)

Maintenance action is required within 10 hours of APU operation.

Question 2

What is the maximum APU Rotor speed?

Answer 2

Maximum N (ECAM display) 107%

The APU automatically shuts down at 107 % N speed, that appears on the ECAM. This corresponds to an actual N speed of 106 %.

Question 3

Maximum EGT (A320s)?

Answer 3

675 C

Question 4

APU Starter limit?

Answer 4

After 3 starter motor duty cycles, wait 60 min before attempting 3 more cycles.

Question 5

APU operation and restart limit (A320/A319)?

Answer 5

FL410 or 41,000 feet

Electrical only from FL225 to FL410

*Reduced Generator loads in flight at the upper FLs. See APU limitations - Envelope and Table.

Question 6

APU battery restart limit (Emergency Electrical Configuration)?

Answer 6

FL250 or 25,000 feet

Question 7

APU bleed limit [Bleed+Elec] (A320)?

Answer 7

FL225 or 22,500 feet (Up to one pack only)

FL150 or 15,000 feet (For two packs)

FL200 or 20,000 feet (For engine starting)

Question 8

What is the APU Bleed altitude limit for engine starting in-flight?

Answer 8

FL200 or 20,000 feet

Question 9

What is the in-flight APU Bleed limit using one pack only?

Answer 9

FL225 or 22,500 feet

Question 10

What is the in-flight APU Bleed limit using both packs?

Answer 10

FL150 or 15,000 feet

Question 11

Air bleed extraction for wing anti-icing is not permitted. True or False?

Answer 11

True

Question 12

The APU bleed can be used for Wing Anti-Ice. True or False?

Answer 12

False.

Air bleed extraction for wing anti-icing is not permitted.

Question 13

APU ground starting and operating limit?

Answer 13

14,750 feet

*Refer to APU Limitations - Envelope