Air Systems (Bleed)

Question 1

Bleed Air is used in which systems? AOM II 2–34

Answer 1

PAWS HAD SALT
Pressurization
Air Conditioning
Water Pressurization (potable)
Smoke Detection (cargo compartment)
Hydraulic Reservoir Pressurization
Aft Cargo Heat
Demand Pumps (Air-Driven Hydraulic; GE 1&4, PW ALL)
Starters (engines)
Anti-Ice (wings and engines)
Leading Edge Flaps
Thrust Reversers

Question 2

Can the APU provide Bleed Air in flight? Up to what altitude? AOM II 7-36

Answer 2

Yes, for one Pack only. Up to 15,000’

Question 3

Turning an “Engine Bleed” switch OFF does what? AOM II 2-13, 2-34

Answer 3

Closes the:
Engine Bleed Air Valve
PRV - Pressure Regulating Valve
(will open for NAI and TR.
HP Valve - High Pressure Valve
(will open for NAI and TR.

Question 4

If the switch is OFF, is NAI still available for that engine? Thrust Reversers?

Answer 4

A: - Yes, is still available unless;
HP valve failed OPEN
PRV failed closed
PRV closed automatically as a result of a Bleed Air Overheat
Engine Starter Valve has NOT closed
B: - Yes, T.R. are still available, unless;
PRV failed closed
PRV closed automatically as a result of Bleed Air Overheat
Engine Starter Valve has NOT closed

Question 5

What will illuminate the SYS Fault light? AOM II 2-12

Answer 5

Bleed Air Overheat
Bleed Air Overpressure
HP Bleed Valve and/or
PRV OPEN when commanded closed.

Question 6

With the SYS FAULT light illuminated, is reversing available upon landing? AOM II 2-35

Answer 6

YES, unless light is on due to an overheat.

Question 7

Which unit in the Bleed Air system reduces Bleed AIr temperature? AOM II 2-34

Answer 7

Fan Air Pre-Cooler

Question 8

With a BLD 1,2,3,4, OVHT/PRV what systems are no longer available? AOM II QRH 2-3, 2-39, 2-35

Answer 8

Nacelle Anti-Ice
Reverse Thrust

Question 9

APU Bleed Air is supplied to which duct? AOM II 2-37

Answer 9

Center Section of the Bleed Air duct

Question 10

Where is the Duct pressure displayed? AOM II 2-14, 2-16

Answer 10

Primary EICAS
ECS Synoptic