Pneumatics

Question 1

What compressor stage is HP air taken from?

Answer 1

6th

Question 2

What compressor stage does P3 air come from?

Answer 2

6th

Question 3

What compressor stage does P2.5 air come from?

Answer 3

5th

Question 4

How is the HP valve controlled

Answer 4

Electrically

Question 5

How are HP valve operated?

Answer 5

Pbeumatically

Question 6

What are the reasons the HP valve would automatically close?

Answer 6

Bleed air over temp (288 deg C)
  Bleed air over pressure (76 PSI)
 Fire handle is pulled
   Engine is shut down
   Main DC bus power is lost

Question 7

➢What are the reasons the LP valve would automatically close?

Answer 7

Bleed air over temp (288 C)
Bleed air over pressure downstream of valve (43 PSI)
Fire handle is pulled
Air conditioning pack over temps (225 C)
Air conditioning duct over temps (82 C)

Question 8

What does a BLD CLOSED light indicate?

Answer 8

Bleed valve is closed

Question 9

➢What does a BLD FAULT light indicate?

Answer 9

Bleed air temperature excessive (>288 C)
Regulated pressure excessive (>43 PSI)
Valve fails to close when signaled to close

Question 10

➢What does a HP HIGH light indicate?

Answer 10

Valve fails to close when signaled to close

Question 11

➢Are the pneumatic systems interconnected?

Answer 11

Yes, cross valve

Question 12

When can cross valve be used?

Answer 12

On the ground only

Question 13

What is required for the XVALVEto open?

Answer 13

One engine bleed valve closed

Question 14

How is the XVALVE controlled?

Answer 14

Electrically

Question 15

How is XVALVE operated?

Answer 15

Pneumatically

Question 16

What does a XVALVE OPEN light indicate?

Answer 16

Cross valve open

Question 17

What does a RECIRC light indicate?

Answer 17

Recirculation fan underspeeds

Question 18

Does manual mode provide temp limiting?

Answer 18

No, only auto mode does

Question 19

➢In manual mode how long does it take to move the control valve full travel ?

Answer 19

6 to 8 seconds

Question 20

What does a AVIONICS VENT light indicate?

Answer 20

Fault occurs in the avionics vent fan

Question 21

When is the only time HP air is automatically provided?

Answer 21

When LP is insufficient (Ng

Question 22

➢If electrical power fails what position will the LP valve be in?

Answer 22

Open

Question 23

➢If electrical power fails what position will the HP valve be in?

Answer 23

Closed

Question 24

On the air conditioning panel an amber DUCT OV TEMP indicates?

Answer 24

ACM compressor discharge overheating

Distribution duct over heating

Question 25

What other valve automatically closes with this light?

Answer 25

Corresponding engine bleed valve

Question 26

➢What cools the Recirc fan?

Answer 26

Bleed air

Question 27

Will the AIRCOND master caution activate with a RECIRC amber light?

Answer 27

No

Question 28

The temperature control knobs sets cabin temp to what range in the AUTO mode?

Answer 28

18 to 29 C

Question 29

➢Is the RECIRC fan temperature protected?

Answer 29

Yes, thermal cutoff will turn off till it cools then allows fan to turn on

Question 30

What does the CABIN PRESS light indicate?

Answer 30

Cabin altitude above 10,000 ft | Cabin pressure exceeds 7.5 PSI

Question 31

What controls the outflow valves?

Answer 31

Electric and Pneumatic

Question 32

In flight, activation of PRESS DUMP opens?

Answer 32

Primary outflow valve

Question 33

What compressor stage is the LP air taken from?

Answer 33

5th

Question 34

➢On ground, activation of PRESS DUMP?

Answer 34

Primary and secondary outflow valves fully open

Question 35

The outflow valves limit negative pressure to?

Answer 35

-0.5 PSI

Question 36

If vacuum pressure is lost, the outflow valves revert to?

Answer 36

Closed

Question 37

➢In manual pressurization mode what position is the primary outflow valve in?

Answer 37

Closed

Question 38

Where is the secondary outflow valve located?

Answer 38

Rear pressure bulkhead

Question 39

What rate of cabin VSI does the detent on the auto controller provide?

Answer 39

500 fpm up and 300 fpm down