Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

United 737 > Air Conditioning > Flashcards

Air Conditioning Flashcards

1
Q

The ____pack provides air directly to the flight deck with excess air flowing to the mix manifold.

A

Left

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The ____pack and the __________ also enters the mix manifold which is then distributed to the cabin.

A

right , recirculation system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

A _____ pack in ____flow will maintain pressurization and acceptable temperatures throughout the a/c operating envelope.

A

single, high

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The APU can supply suffient bleed air for ____ packs on the ground but only ____ pack in flight.

A

2, 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

T/F: A single engine can be used to operate 2 packs.

A

FALSE.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

AUTO on the temperature selector does what?

A

provides automatic temp control for that part of the cabin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

ZONE TEMP lights indicate what?

A

a problem with the associated zone temperature. The duct has overheated and the trim air modulating valve closes to prevent further overheat. A TRIP RESET can work to reopen the valve provided the duct has cooled.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

CONT CAB light indicates:

A

a duct temp overheat or failure of both flight deck pri and stby temp control.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

FWD or AFT CAB indicates:

A

a duct temp overheat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

RAM DOOR FULL OPEN indicates what:

A

ram air doors in the full open position (blue light)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what does TRIM AIR do?

A

opens and closes the pressure regulating and shutoff valve.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

L or R RECIRC FAN in auto means :

A

fan operation is dependent on the PACK settings.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

PACK light indicates:

A

the pack has tripped off or both pri and stby pack controls have failed or an overheat is sensed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

If a fault condition has been corrected and the TRIP RESET is pressed what happens?

A

resets the BLEED TRIP OFF, PACK or ZONE TEMP lights and the related valves open.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Conditioned air for the flight deck branches into what 3 things:

A

floor, ceiling and foot level outlets. Provides warming or cooling and defogging.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How is conditioned air routed to the cabin?

A

via an overhead distribution duct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

With both packs in AUTO, what happens when one pack stops?

A

the other goes to high flow.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

When does automatic switching for single pack ops not occur?

A

on the ground or with flaps extended in flight.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

With APU bleed on and BLEED switches to OFF, what happens?

A

The packs go to high flow, regardless of teh # of operating packs or air/ground status or flap position.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

T/F: Ram air pack doors open and close normally in flight, depending on cooling requirements.

A

True.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

For max cooling on ground or during slow flight with flaps no fully retracted, the ram air doors move to the ______.

A

full open position (indicated by blue RAM DOOR FULL OPEN light).

22
Q

What is the point of the ram air deflector doors?

A

prevent slush ingestion into ram air inlets prior to liftoff and after touchdown.

23
Q

Ram air deflector door is dependent upon what?

A

state of air-ground safety sensor.

24
Q

T/F: the pack temp control valve opens & closes in response to electronic controllers, depending on discharge flow req’d.

A

true.

25
Q

T/F: With both pack controllers failed, the pack will continue to operate unless excessive temps cause the pack to trip off.

A

True.

26
Q

CONT CAB refers to what?

A

the flight deck

27
Q

Temperature ranges for conditioned air can be set to a range of _____

A

18C to 30C.

28
Q

T/F: The zone which requires the most cooling causes both packs to produce an air temp to satisfy that zone.

A

True.

29
Q

With the TRIM AIR switch in ON and one pack inop, what happens?

A

Zone temp control is same as two pack ops. All three individual temp settings are upheld.

30
Q

If in single pack ops and trim air off, what happens?

A

the single pack tries to produce a temp that satisfies the avg temp demands of all three zones.

31
Q

The right controller is the primary controller for what?

A

flight deck and forward cabin zone.

32
Q

The left controller is the

A

backup controller for the flight deck and control for aft cabin zone.

33
Q

If either the fwd or aft cabin controller fails

A

the trim air modulating valves close and temperature is averaged between the settings for the two zones.

34
Q

What happens if all zone controls and primary pack controls fail?

A

the stby pack controls command the packs to produce air temps which will satisfy the avg temps demanded of the two cabins.

35
Q

What happens if all temp selectors are in the OFF position?

A

the pack controls cause the L pack to maintain 24C and the R pack to maintain 18C as measured at the pack temp sensors.

36
Q

What is the purpose of the RECIRC FAN?

A

to reduce air conditioning pack loand and the engine bleed air system demand. Switch must be in AUTO to work.

37
Q

What is the flow of air for the RECIRC FANs?

A

cabin and elec equip bay to fwd cargo bay where it is filtered and sent to mix manifold.

38
Q

In flight, when do the RECIRC FANs not operate both at a time?

A

If either pack is in HIGH, the left fan does not operate while the the right fan does not operate if both pack in HIGH.

39
Q

If on the ground and both packs high, which RECIRC FAN operates?

A

right fan continues to operate and left shuts down.

40
Q

The equipment coolings system cools what?

A

electronic equipment in the flight deck and the E&E bay.

41
Q

T/F: the equipment cooling system has both alternate and normal supply and exhaust fans?

A

True

42
Q

Equipment cooling system: __________ fans are on the aircraft ceiling while ________fans are located underneath.

A

supply, exhaust.

43
Q

T/F: Some heating for the forward cargo compartment comes from the cabin air through the recirculation fan system which is then directed through the compartment lining.

A

True.

44
Q

Heat for the Fwd Cargo compartment is also supplied from the equipment cooling system provided what?

A

the overboard exhaust valve is closed

45
Q

What does the OFF light mean on the EQUIP COOLING panel?

A

illuminates for a failure of the associated fan and resulting low air flow. Can also mean a pressurization problem so check pressurization.

46
Q

How can you reduce the load on a pack with the zone switches?

A

Move to a warmer setting.

47
Q

If both PACK lights are on, what might happen?

A

May indicate both pack valves have closed and it could result in a gradual loss of cabin pressure and eventually a CABIN ALTITUDE warning. Descent must be made to the higher of 10,000 feet or the lowest safe altitude.

48
Q

If at level off at lower altitude after dual PACK failure what can happen?

A

Temperatures may rise quickly. Speed should be kept at or above 290 kts.

49
Q

Oxygen must be donned above what altitude?

A

10,000 feet.

50
Q

What can improve ventilation after dual PACK failure?

A

opening the outflow valves. You must select the switch to MAN.

51
Q

What is the proper position for the L and R RECIRC FANS with dual PACK lights and outflow valve in full open?

A

R RECIRC FAN = AUTO

L RECIRC FAN = OFF

United 737 (25 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions