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Flashcards in Air Systems Deck (75):
1

Where does APU bleed air enter the pneumatic manifold

Left of the isolation valve

2

Where does external pneumatic air enter the pneumatic manifold

Right of the isolation valve

3

What are all the sources that provide air for the pneumatic system

External air, APU, and 5th and 9th stage engine bleeds

4

An 800 aircraft has three air conditioning zoned. The temperature controllers are in NORMAL and trim air is ON. The two packs will supply at what temp

A temp for the zone requiring the most cooling

5

What happens when an engine bleed switch is placed to ON

If engine bleed air and electrical power are available, the valve opens

6

What does an illuminated engine BLEED TRIP OFF light indicate

Excessive engine bleed air pressure or temperature condition, engine bleed valve closes automatically

7

How is engine bleed air temperature regulated

Controlled engine fan air circulates through a precooler

8

Air for starting the engines is supplied from

The left or right pneumatic manifold

9

Which statements are correct regarding the pneumatic manifold pressure sensors

AC powered; located in left&right pneumatic manifolds

10

What do the duct pressure pointers indicate when one pack valve switch is placed to OFF with the APU providing bleed air and the isolation valve in AUTO

APU bleed pressure shows on both pointers

11

What occurs when the APU bleed air switch is placed to ON

DC power signals valve to open, APU bleed air opens the valve if RPM is above 95%

12

What is the power source for the pneumatic isolation valve

AC power

13

Which statement best described the isolation valve function

Isolates left & right sides of the pneumatic manifold and is closed during normal operation

14

What action causes the pneumatic isolation valve to open when the switch is in the AUTO position

Placing an engine bleed air switch or pack switch to OFF

15

What is the function of the DUAL BLEED light

To warn when the APU may be back pressured by engine bleed air

16

Which valve and switch combination causes the DUAL BLEED light to come on

APU bleed valve OPEN & right engine bleed switch ON, with the isolation valve OPEN

17

What is the crew action for an illuminated DUAL BLEED light prior to engine start

No action. Dual Bleed Light is normal during engine start with APU bleed air

18

Which condition illuminates a WING-BODY OVERHEAT light

All answers are correct

19

What engine stages provide bleed air

The 5th and 9th stage

20

The 9th stage engine bleed air is the primary source of bleed air for pneumatics when the engine is at cruise thrust

False

21

The engine bleed valves are located

Downstream of the 9th stage modulation/ shutoff valve

22

How are the bleed valves operated

They are electrically controlled and pneumatically operated

23

Excessive engine bleed air pressure or temperature will cause what condition to occur

A bleed trip

24

If the APU bleed valve and switch are open, the valve will automatically close with APU shutdown

True

25

A right WING-BODY OVERHEAT light could indicate a bleed leak in all of the following except

In the keel beam area

26

The potable water system pressurization line connects to which part of the pneumatic manifold

The left side

27

The Engine Bleed Valve Trip pressure sensor is located

Before bleed air reaches the engine bleed valve

28

The Engine Bleed Valve Trip temperature sensor is located

After the engine bleed air passes the engine bleed air passes the engine bleed valve and precooler

29

What limitation is imposed when the DUAL BLEED light is illuminated

No more than idle engine power is allowed

30

External pneumatic air can be used to start the number 1 engine

If the isolation valve is open

31

The APU provides bleed air directly to

The left side of the pneumatic manifold

32

The engine bleed valve must be open for ENGINE anti-ice to be available

False

33

What is the normal source of conditioned air for the flight deck with both packs operating(500)

The left pack prior to the mix manifold

34

What is the indication on the respective AIR MIX VALVE position indicator when a pack valve closes(500)

Full COLD

35

Which is correct for pack operation

Bleed sir flows through a heat exchanger, the ACM compressor, a second heat exchanger, then the ACM turbine

36

What does an illuminated PACK TRIP OFF light indicate(500)

Pack valve closed by compressor discharge or turbine inlet overtemp or duct overtemp

37

When are the RAM DoOR FULL OPEN lights extinguished

In cruise with low pack temperature

38

On the ground , what is the proper indication of the ram door position lights

RAM DOOR FULL OPEN lights illuminated

39

What is the function of the turbofan in the ram air exit duct(500)

Augments ram airflow when a pack is operating on the ground or inflight with the flaps not up

40

Which statement is correct regarding the air conditioning system deflector doors

The doors extend on the ground to prevent FOD ingestion

41

What is the purpose of the recirculation fan

Reduced pack air loads & engine bleed demand

42

Where is filtered RECIRC FAN air discharged

Into the mix manifold

43

What occurs when a pack switch is placed to the HIGH position with the other pack switch in AUTO and the RECIRC FAN switch in AUTO(500)

Respective pack goes to high flow & recirc fan shuts down

44

Which statement is correct regarding single pack operation with one pack switch in AUTO and one pack switch OFF inflight

Remaining pack goes to high flow in flight when flaps are up

45

With the RECIRC FAN switch at AUTO , and both pack switches at AUTO, which statement is correct regarding the recirculation fan operation(500)

Recirc fan shuts down when either pack switch is placed to HIGH

46

What does an illuminated DUCT OVERHEAT light indicate(500)

Duct has overheated and mix valves have driven full COLD

47

How is hot air removed from the circuit breaker panels and the E&E compartment equipment

By either the main or alternate equipment cooling fans

48

Which statement is correct regarding operation of the flow control valve(500)

Closes when cabin pressure differential reaches 2.5 psid

49

What does an illuminated EQUIP COOLING OFF light indicate

No airflow from the respective equipment cooling fan

50

How is the forward cargo compartment heated when cabin differential pressure is above 2.5 psi with the forward outflow valve closed(500)

The recirc fan maintains airflow around the outside of the compartment

51

Which systems are reset by means of the TRIP RESET switch(500)

DUCT OVERHEAT, PACK TRIP OFF & BLEED TRIP OFF

52

How are the pack & isolation valve switches positioned for a BLEEDS-OFF takeoff

The right pack in AUTO, the isolation valve switch in AUTO, and the left pack in AUTO

53

E&E compartment cooling air flow is normally provided by the

Equipment cooling fan

54

With the recirc fan switch in AUTO, the fan(500)

Operates if one pack is turned OFF and the other is in AUTO

55

Inflight, when both air conditioning packs are operating and the Recirc Fan is in Auto, placing a pack switch to High(500)

All answers are correct

56

With both packs operating , if air conditioning smoke appears in the cockpit and in the cabin, the most likely source is(500)

Left air conditioning pack

57

Overheat temperature sensors that will cause a pack trip are located in the(500)

ACM compressor discharge duct, turbine inlet duct, and supply duct

58

When parked at the gate, external conditioned air temperature_______controlled by the packs

Is not

59

Bleed air for the pack is_____as it passes through the primary heat exchanger

Cooled

60

Each pack has a temperature selector. The selector on the left controls the temperature for(500)

Flight deck

61

With the pack switch turned OFF, the pack valve closes and the mix valves______(500)

Move to full cold

62

With the aircraft airborne, when is the forward outflow valve closed(500)

When the recirculating fan is operating

63

Which model 737 has a TRIM AIR switch on the overhead panel

800 model

64

Which of the following models has a Forward Outflow Valve

500

65

What occurs when the FLT GND switch is placed to FLT with the aircraft on the ground, packs ON, doors CLOSED, and engine bleed air avail(500)

The main outflow valve modulates as necessary to maintain the aircraft at 200 feet below departure field elevation

66

What altitude is set in the STANDBY CAB ALT indicator when operating in AUTO during the receiving aircraft check

200 ft below landing field elev

67

What altitude is set in the STANDBY CAB ALT indicator during the receiving aircraft check when operating the flight with the SAtANDBY pressurization system(auto system inop)

Takeoff field elev minus 200ft

68

What does an illuminated OFF SCHED DESCENT light indicate

Aircraft descending without having reached the selected cruise altitude

69

Which statement is correct regarding the outflow valve position indicator

Operates in all pressurization modes with AC power available

70

All of the following items control the ram air system ram door and exhaust louvers except

The pressurization controller

71

When is the RAM DOOR FULL OPEN light illuminated

On the ground, or in flight with the flaps extended

72

Illumination of the amber pressurization OFF SCHED DESCENT light indicates what situation

The airplane is descending prior to reaching the selected flight altitude

73

What is the maximum allowable differential pressure for takeoff

.125 psid

74

The air conditioning packs may be operated in HIGH during a bleeds on takeoff

False

75

With the aircraft at the maximum certified altitude and one pack operating, what is the lowest cabin altitude that can be maintained

8000 ft