Pneumatics

Question 1

During normal operation, when would you expect to see the HP valve open?

Answer 1

At low engine speed when the pressure and temperature of the IP air are too low.

Question 2

What is the normal bleed air pressure and temperature? How are they regulated?

Answer 2

45 psi +/- 5
200 degrees

Regulated by bleed valve and downstream precooler

Question 3

With X bleed in auto, what happens when the APU bleed valve opens?

Answer 3

XBLEED opens and ENG BLEED closes

Question 4

Is WAI allowed if only one bleed system is operating and both packs are on?

Answer 4

Nope

Question 5

What provides bleed leak detection for the ENG pylons, Wings, and APU?

Answer 5

Pylons and APU, single loop detector
Wings, double loop

Question 6

What happens if BMC1 or 2 fails?

Answer 6

BMC 1 - ENG BLEED LEAK and APU BLEED LEAK warnings lost

BMC 2 - ENG BLEED LEAK warning lost

In both cases the alternate BMC will still provide overpressure/temp and WING LEAK monitoring.

Question 7

What should you not do I’d GD LP is connected?

Answer 7

Use packs