2: Air Systems

Question 1

BLEED light on the max. What does it indicate?

Answer 1

Over temp, over- and under pressure
Bleed system failure
Incorrect config after T/O or GA

Question 2

BLEED TRIP OFF light on NG. What does it indicate?

Answer 2

Excessive bleed air temp or pressure

• the related bleed air valve closes automatically
• requires a reset

Question 3

Recirculation fans in auto- What is the requirements for them to turn off in-flight?

Answer 3

Left- turns of if either pack switch in high
Right- turns off if both pack switches in high

Question 4

Recirculation fans in auto- What is the requirements for them to turn off- on ground?

Answer 4

Left- both pack switches in high
Right- doesn`t turn off even with both pack switches in high

Question 5

PACK Light-

Answer 5

Both NG and MAX:
* indicates pack trip off
* or failure of both primary and standby pack controls

NG only:
* during recall, indicates failure of either primary or stby pack controls

MAX only:
* indicates failure of the Flow Control Valve to open when commanded
* incorrect pack switch config after T/O

Question 6

BLEED with a configuration discrepancy. How long after T/O or GA does it illum?

Answer 6

45 seconds after the flaps are up

Question 7

WING-BODY OVERHEAT Light. What does it indicate?

Answer 7

Bleed air duct leak (Left)
* Engine strut
* Inboard wing leading edge
* Air conditioning bay
* Keel beam
* APU bleed air duct

Question 8

Operating more than one pack from one engine bleed (NG and MAX)

Answer 8

NG- not allowed
MAX- not allowed on the ground,
in flight, one bleed is capable of supplying air to both
packs

Question 9

Overboard Exhaust Valve, what is normal config and when does it open?

Answer 9

In flight, ​at higher cabin differential pressures, the overboard exhaust valve is normally ​closed and exhaust air is diffused to the lining of the forward cargo compartment
However, the overboard exhaust valve is driven open if either pack switch is in ​high and the right recirculation​ fan is​ off.​ This allows for increased ventilation in ​the smoke removal configuration. ​
Note:​ During​ pressurized flight, the overboard exhaust​ valve will be commanded ​to a smoke mode upon a Forward Cargo Fire Alarm.

Question 10

Smoke Removal Config

Answer 10

Either pack high and right recirc fan off. Which means from normal config, if you switch both packs to high your right recirc will turn off and you will have smoke removal config

Question 11

TRIP​ RESET​ Switch

Answer 11

• resets BLEED, PACK, or ZONE TEMP​ lights
• related engine bleed air valve opens, or related pack valve opens, or ​related trim air modulating valve opens