ATA 36 - Pneumatic

Question 1

Description of the pneumatic system

Answer 1

Cf diagram

Question 2

How many motors for the crossbleed valve ?

Answer 2

2
1 for AUTO mode
1 for MAN mode

Question 3

What bleed pressure does BMC maintain at engine output ?

Answer 3

45 psi from IP source
36 psi from HP source if IP source is not enough ( idle on ground for example)

Question 4

Temperature of bleed air after air fan cooling ?

Answer 4

Around 200°C

Question 5

If air leak is detected on left side (wing, pylon 1) what valves automatically close ? And right side ?

Answer 5

Left:
ENG 1 bleed valve, APU bleed valve, Xbleed valve (except if due to starter)

Right:
ENG 2 bleed valve, Xbleed valve (except if due to starter)

Question 6

In case of BMC 1(2) fault what are the consequences ?

Answer 6

Leak detection ENG 1 and APU lost
Or
Leak detection ENG 2 lost

Fault light on Bleed lost, Auto bleed valve control lost

Other function are took over by remaining BMC (Overpressure, overtemperature, wing leak)

Question 7

In flight if the bleed air pressure is insufficient even with the HP valve open, what happens ?

Answer 7

FADEC increase idle setting

Question 8

Temperature regulation is achieved by the PRECOOLER before Packs which regulates and limits the temperature at XXX °C ?

Answer 8

200°C

Question 9

APU running and ENG BLEED ON. What are the positions of the valves ?

Answer 9

XBLEED open
ENG BLEED closed

Question 10

How is detected a pneumatic leak ?

Answer 10

Heat detectors close to the bleed pipes

Question 11

HP bleed valve automatically closes when there is a low or high pressure upstream. True or False ?

Answer 11

True

Question 12

When you select APU bleed ON, which bleed valves close and open ?

Answer 12

APU bleed valve and crossbleed open.
Eng bleed valves close