United 737 Air Systems/Pneumatics/AC/Pressurization

Question 1

On the cabin pressurization panel, what has occured if both the Amber AUTO FAIL light and the green ALTN light is illuminated?

Answer 1

A single channel controller failure has occured

Question 2

The OFF SCHED DESCENT light indicates the aircraft began descent before having reached the planned cruise altitude. What does the controller program the cabin to?

Answer 2

To land at the takeoff field elevation without further pilot inputs

Question 3

Which stages of the compressor section is bleed air obtained from?

Answer 3

5th and 9th

Question 4

The ___ high stage valve modulates open to maintain proper pressure when 5th low stage pressure is insufficient

Answer 4

9th

Question 5

The engine bleed air valve is normally ______ operated and DC power activated

Answer 5

Pneumatically

Question 6

What does the illumination of the BLEED TRIP OFF light idicate?

Answer 6

Engine bleed air temperature or pressure exceeds a predetermined limit

Question 7

When the BLEED TRIP OFF light illuminates, what effect does this have on the engine bleed air system?

Answer 7

The respective engine bleed air valve closes automatically

Question 8

The isolation valve is ____ when the isolation valve switch in AUTO, both engine bleed air switches ON, and both air conditioning pack switches AUTO or HIGH.

Answer 8

CLOSED

Question 9

The isolation valve is ____ when the isolation valve switch is in AUTO, if either an engine bleed air switch or a pack switch is positioned OFF

Answer 9

OPEN

Question 10

Turning the APU bleed air switch OFF with the PACK switches in AUTO will cause the isolation valve to open

Answer 10

FALSE

Question 11

The APU bleed air valve is ____ operated and ___ activated

Answer 11

pneumatically; DC

Question 12

Engine thrust must be ___ with the DUAL BLEED light illuminated

Answer 12

Limited to Idle

Question 13

___ causes a WING BODY OVERHEAT condition.

Answer 13

A bleed air duct leak

Question 14

Which WING BODY OVERHEAT light will illuminate if a leak in the bleed duct from the APU occurs?

Answer 14

LEFT

Question 15

The isolation valve____ if either engine BLEED air or air condition PACK switch is positioned OFF with the ISOLATION VALVE switch in AUTO

Answer 15

Automatically Opens

Question 16

Conditioned air from which PACK, upstream of the mix manifold, flows directly to the flight deck?

Answer 16

Left Pack

Question 17

Air from the left pack, air from the right pack, and air from the recirculation system is combined within the ___

Answer 17

Mix Manifold

Question 18

On the ground, the APU can supply air for ___for all operations

Answer 18

2 packs

Question 19

With the Air Conditioning PACK switches in AUTO and both packs are operating

Answer 19

the packs provide “Normal air flow”

Question 20

When one pack is operating, _____ with the air conditioning PACK switches in AUTO

Answer 20

the operating pack provides HIGH AIR FLOW!

Question 21

Anyime the pack valve closes on the 737 700 the air mix valves are driven to the ____ position automatically

Answer 21

FULL COLD

Question 22

In the automatic temperature mode on the 737 700 the _____ are operated by the automatic temperature controller

Answer 22

Air Mix Valves

Question 23

The automatic temperature controller is bypassed when the temperature selector is positioned to ____ on the 737 700.

Answer 23

Manual

Question 24

The ram air system is used to provide cooling for what part of the air conditioning systems?

Answer 24

Heat Exchangers

Question 25

A DUCT OVERHEAT light causes the appropriate air mix valve to drive ______ on a 737 700

Answer 25

FULL COLD

Question 26

When a PACK TRIP OFF light illuminates, the pack valve ______ on the 737 700.

Answer 26

Automatically closes and the mix valve drives full cold

Question 27

In a 737 800 ___ if an amber ZONE TEMP light illuminates.

Answer 27

the MASTER CAUTION light will illuminate and the trim air valve closes

Question 28

The recriculation fan system ____ the engine bleed air demand and air conditioning load

Answer 28

REDUCES

Question 29

What does the TRIP RESET switch reset?

Answer 29

1. DUCT OVERHEAT on the 737 700 or the ZONE TEMP on the 737 800 2. BLEED TRIP OFF, PACK TRIP OFF

Question 30

On the 737 800 what is indicated by the PACK light?

Answer 30

A pack trip off or Failure of both primary and standby pack controllers

Question 31

Cabin air outflow controlled by

Answer 31

Outflow Valve and the Overboard Exhaust Valve

Question 32

On the Cabin Pressurization Panel, what does an illuminated amber AUTO FAIL light indicate?

Answer 32

Automatic Pressurization system failure is detected

Question 33

Manually positioning the outflow valve to OPEN will cause cabin altitude to ___

Answer 33

Climb

Question 34

The main outflow valve is the overboard exhaust exit for the majority of the air circulated through the passenger cabin and is actuated by one of the ___ DC motors

Answer 34

THREE

Question 35

On the cabin altitude panel, the ___ on the CABIN altimeter/ Differential Pressure indicator indicates the cabin altitude in feet

Answer 35

INNER SCALE

Question 36

On the Cabin altitude panel, the ___ on the CABIN Altimeter/Differential Pressure indicator indicates the differential pressure between cabin and ambient PSI

Answer 36

OUTER SCALE

Question 37

The intermittent cabin altitude warning horn can be cut out ___

Answer 37

by pushing the ALT HORN CUTOUT Switch

Question 38

At _____ cabin altitude the intermittent cabin altitude warning will sound

Answer 38

10,000'

Question 39

Cabin rate of climb displayed ____

Answer 39

on the cabin rate of climb indicator

Question 40

On the Cabin Pressurization Panel, ____ & ____modes automatically pressurize the aircraft.

Answer 40

AUTO & ALTN

Question 41

What precools engine bleed air?

Answer 41

A precooler, or heat exchanger

Question 42

Does the APU bleed air switch affect the isolation valve position?

Answer 42

NO

Question 43

Does the APU bleed air valve automatically close when the APU is shut down?

Answer 43

YES

Question 44

The Wing Body Overheat Test Switch ____

Answer 44

All answers are correct

Question 45

Conditioned air for the cabin comes from ____

Answer 45

Air from the Aircraft AC or a preconditioned ground source

Question 46

With the air conditioning PACK switch in HIGH ____

Answer 46

The respective pack provides high air flow

Question 47

In a 737 700- a PACK TRIP OFF is caused by

Answer 47

A pack temperature exceeding limits

Question 48

What makes the equipment cooling OFF light illuminate?

Answer 48

Loss of air flow due to failure of an equipment cooling fan

Question 49

The Pressurization Mode Selector in the MAN mode, the outflow valve switch takes approx. _____ second to move the outflow valve in the full range of motion.

Answer 49

20 seconds

Question 50

T/F 737 700: The pack valve will close if the cooling cycle overheats and is associated with a PACK TRIP OFF light

Answer 50

True