Systems - Pneumatics

Question 1

What 2 valves are controlled electric/electric?

Answer 1

ISOL valve and wing anti ice valve

Question 2

What are the only SOVs that fail open?

Answer 2

Cowl anti ice SOVs

Question 3

Function of LCV (load control valve)

Answer 3

Control amount of bleed air from APU. Fail safe closed.

Question 4

Bleed valves __ controlled and __ operated

Answer 4

electrically // pneumatically

Question 5

What is cabin max positive differential pressure?

Answer 5

8.7 psi

Question 6

Max alt for single pack ops?

Answer 6

31,000 feet

Question 7

APU bleed air duct contains a one way check valve to prevent…

Answer 7

engine bleed air from backing up into APU

Question 8

Can both cowls be heated from one engine?

Answer 8

No.

Question 9

What is function of PRSOVs? (pressure regulating shut off valves)

Answer 9

Regulate discharge pressure to 45 psi +/-3

Question 10

CABIN ALT caution message

Answer 10

8,500 feet

Question 11

CABIN ALT warning message and “CABIN PRESSURE” aural

Answer 11

10,000 feet

Question 12

DIFF PRESS warning message and “CABIN PRESSURE” aural

Answer 12

8.6 dP

Question 13

When do pax masks drop?

Answer 13

Cabin alt above 14,000 feet

Question 14

What altitude can EMER DEPRESS not be used above?

Answer 14

15,000 feet

Question 15

What stage(s) of the engine compressor supplies air to operate the pneumatically powered aircraft systems?

Answer 15

6th and 10th

Question 16

Which valve is NOT represented on the ECS or ANTI ICE synoptic pages?

Answer 16

One way check valve