APU

Question 1

How can you tell the APU is up to speed and the generator is available?

Answer 1

APU electrical power is available

Question 2

When would the corresponding APU N% Speed be displayed in amber or red?

Answer 2

When an overspeed occurs

Question 3

What is indicated when the APU EGT indication is displayed in amber or red?

Answer 3

An over-temperature condition

Question 4

The APU START pb is pressed and illuminates blue. What does this mean?

Answer 4

The APU starter is energized

Question 5

With external power supplying the buses and the APU operating, what action is required to select APU
power?

Answer 5

Deselect external power by pushing the EXT PWR pb.

Question 6

When would the APU fault light illuminate?

Answer 6

APU automatic shutdown

Question 7

What are some possible reasons for an APU auto shutdown?

Answer 7

High oil temp, low oil pressure, overspeed, etc.

Question 8

Is altitude a consideration when considering use of the APU as a source of bleed air and/or electrical
power?

Answer 8

Yes.