APU

Question 1

When does the EICAS memo message APU RUNNING display?

Answer 1

When the APU selector is ON and,
APU N1 RPM exceeds 95% N1.

FCOM 2; 7.40.3

Question 2

Is electrical power available from the APU in flight?

Answer 2

•No

FCOM 2; 7.30.1

Question 3

Can the APU be operated in flight?

Answer 3

•Yes
NB: When left running for takeoff it can be operated in
flight up to 20,000 feet

FCOM 2; 7.30.1

Question 4

How long should you wait before turning the battery switch OFF after the APU selector is rotated to OFF, and why?

Answer 4

•2 minutes
•Allows a complete shutdown sequence,
with fire detection capability.

FCOM 2; 7.30.2