Chapter 2 - Air Systems

Question 1

Does the compartment INOP light illuminate if the temperature control is OFF or trim air is OFF ?

Answer 1

Yes.

Question 2

What is the meaning of the pack INOP light ?

Answer 2

• Pack overheat

- Fault

Question 3

What is the meaning of the PACK OFF light ?

Answer 3

Pack valve is closed.

Question 4

Does the recirculation INOP light illuminate if the recirculation switch is OFF ?

Answer 4

Yes.

Question 5

How is the air warmed from the should and foot heaters ?

Answer 5

Electrically.

Question 6

When is the equipment cooling NO COOLING light illuminated ?

Answer 6

Only in OVRD mode. No reverse air flow is being delivered !

Question 7

What is the approximate ROC and ROD of the cabin altitude when the auto rate control is set at the index mark ?

Answer 7

+500 fpm, -300fpm

Question 8

When does the cabin pressurization AUTO INOP illuminate ?

Answer 8

When both controllers are inop or when MAN has been selected.

Question 9

When does the CABIN ALT light extinguish again ?

Answer 9

When cabin altitude is less than 8,500ft.

Question 10

When does the APU VALVE light illuminate ?

Answer 10

Valve disagreement.

Question 11

What is the meaning of the engine BLEED light ?

Answer 11

Bleed overpressure. The HPSOV or/and PRV are open, and should be closed.

Question 12

Which has priority: high bleed air demand or high pack output ?

Answer 12

high bleed air demand. In this situation, high pack output is not possible.

Question 13

What does the standby N(ormal) pack control do ?

Answer 13

Delivers constant, moderate temperature air.

Question 14

How is temperature controlled with trim air OFF ?

Answer 14

Average air temperature for all zones.

Question 15

What is the difference in equipment cooling on the ground or in-flight ?

Answer 15

On the ground, the supply and exhaust fan are active, hot air is expelled overboard if needed. In-flight it is normally only recirculated using the exhaust fan.

Question 16

What is the normal cargo temperature when heated ? What about the vented bulk cargo temperature ?

Answer 16

• 7 deg

- 18 deg

Question 17

When does the cargo OVHT light illuminate ?

Answer 17

> 32deg, the heating shutoff valve is automatically closed.

Question 18

What happens with cabin pressure during T/O ?

Answer 18

Slight positive pressure

Question 19

What happens with cabin pressure shortly before landing ? And at touchdown ?

Answer 19

Cabin pressure slightly below landing altitude. At touchdown, the outflow valve opens.

Question 20

When is the outflow valve automatically closed ?

Answer 20

When cabin altitude > 11,000ft, in both automatic and manual modes.

Question 21

Do the engine bleed valves close automatically under certain normal operations ?

Answer 21

Yes. (low demand on the ground, engine start,..)

Question 22

Is reverse air flow to the APU possible ?

Answer 22

No, because of a check valve.

Question 23

Until which altitude is APU bleed available ?

Answer 23

17,000 ft.

Question 24

Are the L/R isolation valve normally open ?

Answer 24

No, normally closed, except for engine start.

Question 25

Do the HPSOV and PRV normally close when the engine bleed air valves closes ?

Answer 25

Yes.

Question 26

Engine bleed air valve is closed, but engine anti-ice is activated. Is EAI available ?

Answer 26

Yes, the PRV opens but the engine bleed air valve remains closed.

Question 27

Which side of the bleed air system is ground pneumatic air added ?

Answer 27

To the L side, between the L isolation valve and the L pack.

Question 28

Is reverse thrust affected if the respective engine bleed valve is closed ?

Answer 28

Yes, it may be affected. The PRV is located before reverse thrust bleed air, and may be closed.