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Flashcards in Pneumatics Deck (15)
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1
Q

In flight, what is the primary bleed souce?

A

Engine Bleed

2
Q

What are the 2 compressor stages from the engines? Which stage is primary?

A
  • Intermediate pressure stage (IP)
  • High pressure stage (HP)

In flight IP stage is primary. HP stage only used when insufficent IP air such as engine at idle

3
Q

What prevents HP air from entering the IP stage?

A

Check Valve

4
Q

What stops HP air from entering system?

A

The High Pressure Valve

5
Q

Can HP and IP air be used at the same time?

A

NEVER, always one OR the other

6
Q

Where does air from either the HP or IP stage go?

A

Enters a common engine bleed valve which is also a shutoff and pressure regulating device. This valve can be controlled from the cockpit.

7
Q

Can APU used for bleed air?

A

Yes, limited to 20,000 ft. The APU is the primary bleed source when the APU is running. Eng bleed valves close.

8
Q

What system controls and monitors the pnumatic system?

A

BMC - Bleed Monitoring Computers. One for each engine bleed system. BMC 1 also controlls APU bleed.

9
Q

Where are bleed leak detection loops installed?

A
  • APU Ducting
  • Eng Pylon Ducting
  • Wing Ducting
10
Q

If a leak is detected…

A

Signal sent to BMC wich will isolate the area and alert the crew via ECAM

11
Q

How do the leak detection loops work?

A

Two independent loops installed and monitored by the BMCs. BOTH loops must sense heat rise before alert is sent. If one loop inop, a single loop will alert.

12
Q

Closing an engine bleed valve…

A
  • Shuts down associated pack
  • Closes HP valve
13
Q

Name the conditions under which the BMC would automatically close an engine bleed valve.

A
  • Overtemp
  • Over pressure
  • Bleed leak detected
  • Eng start sequence commanded
  • APU bleed selected on
14
Q

What position do the ENG bleed valves fail?

A

Fail closed. Spring loaded to close when engine not running or if reverse pressure sensed.

15
Q

Can a single bleed supply both packs and anti-ice at the same time?

A

NO - if anti-ice is needed, one pack must be shut down.