Pneumatic System

Question 1

Pneumatic system provides

Answer 1

1. AC distribution system
2. AC cooling system
3. Anti-g system
4. Canopy seal system
5. Canopy pressurization
6. Cockpit temperature control
7. Demist System
8. Rain removal/ de-icing system
9. Anti-ice system (engine only)
10. Fuel System 4.5 bar press
11. Hydr reservoir press

Question 2

In the AC system cooling of the 2 heat exchangers is granted by:

Answer 2

Ram air while in flight
Ejector shut off valve, that opens automatically at speed below 165Kts

Question 3

The mixing valve (mixing hot air w/ cold air by AC) is controlled by

Answer 3

Temperature Control Box

Question 4

Emergency Cockpit ventilation system is composed of:

Answer 4

Ram air scoop
Over pressure dump valve

Question 5

Below 8000ft you can pull the ram air scoop whenever needed, but what actions must be taken if above 8000ft?

Answer 5

Operate CABIN PRESS switch to OFF, interrupting canopy pressurization first

Question 6

What does operation of ram air scoop handle also operate?

Answer 6

Over pressure dump valve

Question 7

Power required for ventilation system comes from

Answer 7

Essential bus

Question 8

Cockpit pressurization system components

Answer 8

Over pressure dump valve
Pressure regulator valve
Cockpit altimeter control system

Question 9

When does overpressure dump valve close?

Answer 9

At 8000ft climbing

Question 10

Normal operations of cockpit pressure regulation are solved by

Answer 10

Pressure regulator valve

Question 11

Types of pressurization

Answer 11

h<8000 no pressurization
8000<h<16000 linear pressurization
h>16000 differential pressurization

Question 12

When does the over pressure dump valve intervene?

Answer 12

When there’s a malfunction of the Pressure Regulator valve

If ram air scoop handle is pulled

If differential pressure is more than 27.6 +3.4/-0 kPa, or if cockpit is underpressure

Question 13

CAB PRESS turns on if

Answer 13

Cockpit alt> 30.000ft or Cockpit px< 30 +1/-0 kPa
Differential pressure more than 27.6 +3.4/-0 kPa

Question 14

Canopy seal inflates

Answer 14

Automatically after a takeoff because of a switch on the left landing gear leg.
At landing the operation is reversed

Question 15

Air for the all pneumatic system is obtained by

Answer 15

8th stage of the compressor

Question 16

Where does the anti-ice switch take power from?

Answer 16

Primary bus

Question 17

How many parts in the anti-ice system?

Answer 17

Electric part: heaters are energized in the air intakes and air ducts

Pneumatic part: anti-ice valve opens taking air from the compressor and routing it to the engine front face

Question 18

In case of electrical supply failure the engine anti-ice valve

Answer 18

Fails to the open position

Question 19

When operating CABIN TEMP manually, the pilot must pay attention to what?

Answer 19

Not to set too cold temperatures to prevent ice formation in the water separator thus damaging the ducts

Question 20

Effect of pressurization on cockpit altitude should be:

Answer 20

16.000<h<24.000 1/2h +-500ft
h>24.000 1/2h + 1000/2000ft

Question 21

The Temperature Control Box is

Answer 21

Controlled by CABIN TEMP switch, based on 2 probes:
-cockpit temperature probe
-air inlet temperature probe

And it regulates the Mixing Valve for temperature in the cockpit

Question 22

What is the differential pressure maintained by the Pressure Regulator Valve? In normal ops

Answer 22

3.5psi (24kPa)