DB's SY 737 Air Systems

Question 0

ISOLATION VALVE switch:

1. CLOSE
2. AUTO
3. OPEN

Answer 0

1. Closes isolation valve
2. A. Closes isolation valve if both engine BLEED air switches are ON and both air conditioning PACK switches are AUTO or HIGH
   B. Opens isolation valve automatically if either engine BLEED air or air conditioning PACK switches are positioned OFF
3. Opens isolation valve

Question 1

DUAL BLEED light illuminated

Answer 1

1. APU bleed air valve open and engine 1 BLEED switch ON

2. Engine 2 BLEED air switch ON, APU bleed air valve and isolation valve open.

Question 2

WING-BODY OVERHEAT light illuminated

1. left light
2. Right light

Answer 2

1. Overheat from bleed air duct in
   a. left engine strut
   b. left inboard wing leading edge
   c. left air conditioning bay
   d. keel beam or
   e. APU bleed air duct
2. Overheat from bleed air duct in
   a. right engine strut
   b. right inboard wing leading edge or
   c. right air conditioning bay.

Question 3

Engine BLEED Air switches

1. OFF
2. ON

Answer 3

1. Closes engine bleed air valve

2. Opens engine bleed air valve when engines are operating

Question 4

APU BLEED Air Switch

1. OFF
2. ON

Answer 4

1. Closes APU bleed air valve

2. Opens APU bleed air valve when APU is operating

Question 5

Wing-Body Overheat TEST switch - push

Answer 5

1. Tests wing-body overheat detector circuits

2. Illuminates both WING-BODY OVERHEAT lights

Question 6

BLEED TRIP OFF Light - illuminated (Amber)

Answer 6

Excessive engine bleed air temp or pressure
• related engine bleed air valve closes automatically
• requires reset

Question 7

TRIP RESET Switch- Push (if fault condition is corrected)

Answer 7

1. Resets BLEED TRIP OFF, PACK and ZONE TEMP lights
2. Related engine bleed valve, PACK valve, or trim air modulating valve opens
3. Lights remain illuminated until reset

Question 8

CONT CAB ZONE TEMP light

1. illuminated
2. During master recall

Answer 8

1. Duct temp overheat or failure of the flight deck primary and standby temp controller
2. Failure of the flight deck primary or standby temp controller

Question 9

FWD CAB or AFT CAB ZONE TEMP light

1. illuminated
2. During master recall

Answer 9

1. Duct temp overheat

2. Failure of associated zone temp control

Question 10

Temperature Selector

1. Auto
2. OFF

Answer 10

1. Provides automatic temp control for associated zones ranging from 65°F (C) to 85°F (W)
2. Closes the associated trim air modulating position

Question 11

RAM DOOR FULL OPEN light

1. Illuminated
2. When would it normally be illuminated?

Answer 11

1. Ram door in full open position

2. On the ground or during slow flight with the flaps not fully retracted

Question 12

Air Conditioning PACK Switch - OFF

Answer 12

PACK signaled OFF

Question 13

Air Conditioning PACK Switch - AUTO

Answer 13

PACKs regulate to low or high flow, depending on conditions.

Question 14

When do PACKs operate in low flow mode?

Answer 14

With PACK Switches in AUTO and both PACKs are operating.

Question 15

When do PACKs operate in high flow mode automatically?

Answer 15

Both air conditioning PACK Switches AUTO and

1. One PACK not operating
2. Inflight
3. Flaps up

Question 16

When do PACKs operate in high flow mode manually?

Answer 16

1. When operating at least one PACK from APU and both engine BLEED air switches OFF, either Inflight or on the ground
2. When either PACK switch is positioned to HIGH

Question 17

Air Conditioning PACK Switch - HIGH

Answer 17

1. Regulates to high flow

2. Provides maximum flow rate on ground with APU BLEED air switch ON

Question 18

PACK light - Illuminated (amber)

1. During recall
2. On its own

Answer 18

1. Failure of either primary or standby PACK control

2. Indicates PACK trip off (due to excessive heat) or failure of both primary and standby PACK controls

Question 19

TRIM AIR Switch

1. ON
2. OFF

Answer 19

1. Trim air pressure regulating and SOV signaled open

2. Trim air pressure regulating and SOV signaled closed

Question 20

RECIRC FAN Switches - OFF

Answer 20

Fan signaled off

Question 21

RECIRC FAN Switches - AUTO
In-flight
1. Left RECIRC fan
2. Right RECIRC fan

Answer 21

1. Operates if both PACKs are operating unless either PACK switch is in HIGH
2. Operates if both PACKs are operating unless both PACK Switches are in HIGH

Question 22

RECIRC FAN Switches - AUTO - on the ground

1. Left RECIRC fan
2. Right RECIRC fan

Answer 22

1. Operates unless both PACK switch is in HIGH

2. Operates even if both PACK Switches are in HIGH

Question 23

AUTO FAIL light - Illuminated (amber)

Answer 23

1. Single controller failure (with ALTN light on)
2. Dual controller failure (with ALTN light off)
3. Loss of DC power
4. Outflow valve control fault
5. Excessive differential pressure (>8.75 PSI)
6. Excessive rate of cabin pressure change (+/- 2000 ft/min)
7. High cabin altitude (> 15,800ft)

Question 24

OFF SCHED DESCENT light - illuminated (Amber)

Answer 24

Airplane descended before reaching the planned cruise altitude set in the FLT ALT indicator

Question 25

FLT ALT or LAND ALT Indicator displays "88888" or all dashes?

Answer 25

A panel failure was detected after a DC power interruption

Question 26

MANUAL light - illuminated (green)

Answer 26

Pressurization system operating in manual mode

Question 27

ALTN light - illuminated (green) 1. With AUTO FAIL light 2. Without AUTO FAIL light

Answer 27

Pressurization system operating in alternate automatic mode: 1. Indicates a single controller failure and automatic transfer to ALTN mode 2. Pressurization mode selector in ALTN position

Question 28

In which pressurization modes (auto, alternate, or manual) will the outflow valve operate?

Answer 28

All modes

Question 29

Pressurization Mode Selector - AUTO

Answer 29

Pressurization system controlled automatically

Question 30

Pressurization Mode Selector - ALTN

Answer 30

Pressurization system controlled automatically using ALTN controller

Question 31

Pressurization Mode Selector - MAN

Answer 31

Pressurization system controlled manually by outflow valve switch (both auto controllers bypassed)

Question 32

What is the Cabin/Flight Altitude placard used for?

Answer 32

Determining the setting for cabin altitude when operating in manual mode

Question 33

What systems rely on the bleed air system for operation?

Answer 33

1. Air conditioning/pressurization 2. Wing and engine thermal anti-icing 3. Engine starting 4. Hydraulic reservoir pressurization 5. Water tank pressurization (817SY and 818SY) 6. Aspirated TAT

Question 34

Where is engine bleed air obtained from?

Answer 34

The 5th and 9th stages of the compressor

Question 35

The L and R duct pressure indicates a 30 PSI split, but everything else remains normal. Is this a write up?

Answer 35

No. Indications are considered normal as long as there is sufficient air for cabin pressurization.

Question 36

When and why do the deflector doors of the ram air inlet extend?

Answer 36

When on the ground to prevent slush ingestion.

Question 37

If a passenger cabin zone trim air, or all trim air is lost, what temperature will be produced by; 1. The left PACK 2. The right PACK

Answer 37

1. Whatever is selected by the CONT Cabin temp controller | 2. The average of the forward and aft zone temp demands

Question 38

If all zone controls are positioned to OFF, what is this called and what temp will each PACK produce?

Answer 38

Fixed Cabin Temperature produces 75° from the left PACK and 65° from the right PACK.

Question 39

Where does the forward cargo compartment receive its warm air supply from when; 1. Outboard exhaust is open (normally on ground) 2. Outboard exhaust is closed (normally in flight)

Answer 39

1. The passenger cabin exhaust | 2. Electric equipment cooling exhaust

Question 40

At what PSI does the positive pressure relief valves provide safety pressure relief?

Answer 40

They open at 8.95 PSI limiting the differential pressure to a max of 9.1 PSI.

Question 41

When would you expect the overboard exhaust valve (located just after of the E&E compartment) to open?

Answer 41

1. On the ground 2. In flight with low differential pressure 3. For smoke removal (either PACK switch OFF and right RECIRC OFF)

Question 42

How is the take off airport altitude set on pressurization auto controllers?

Answer 42

Automatically using cabin altitude when on the ground.