Systems - Pneumatics / AC / Pressurization

Question 1

What is an easy way to eliminate unwanted galley odors quickly?

Answer 1

Turn off the recirc fans

Question 2

What causes a pack to enter the standby cooling mode?

Answer 2

A fault

Question 3

What does the trim air do?

Answer 3

Heats the different zones

Question 4

Can cabin temperature be maintained with a loss of trim air?

Answer 4

Yes to the average target temp

Question 5

What is the purpose of the bleed isolation switches?

Answer 5

To isolate a bleed leak or to cross bleed air from different sources

Question 6

When will the APU bleed valve open in auto?

Answer 6

Whenever the APU air is available

Question 7

How do you know you are in Standby Cooling Mode?

Answer 7

AIR synoptic will show pack condition

Question 8

When does the cabin altitude limiter close both outflow valves?

Answer 8

During a rapid cabin depressurization or when cabin altitude 15,000 feet

Question 9

What should we be aware of when the equipment cooling system is operating in the override mode (such as smoke detected in the forward cargo compartment) and we are at low altitude / high ambient temperature?

Answer 9

Insufficient cooling of the avionics is possible

Question 10

Why does the flight deck receive air from the left pack at a higher pressure than the passenger cabin?

Answer 10

To keep the differential pressure higher at the flight deck for smoke and odor removal/prevention

Question 11

What do I see on the EICAS screen if I select manual on an outflow valve?

Answer 11

M appears in amber in the outflow depictions

Question 12

What is the external indication that the forward equipment cooling system is inoperative?

Answer 12

Horn in nose wheel well

Question 13

What is the temperature range on the FLT DECK selector?

Answer 13

65 - 85 oF

Question 14

What is the maximum difference between temperature settings for cabin and cockpit?

Answer 14

10 degrees

Question 15

How can you go beyond the AUTO limits?

Answer 15

Manual selection of temperature

Question 16

What is the purpose of the RECIRC FANS?

Answer 16

To reduce fuel consumption by recirculating conditioned air

Question 17

Does the flight deck get recirculated air?

Answer 17

No

Question 18

What does the RESET switch reset?

Answer 18

Any system fault

Question 19

Up to what altitude is APU bleed air available?

Answer 19

20,000 feet

Question 20

Describe the ON position of the bleed air switch.

Answer 20

Armed and will turn ON whenever air is available from its respected source

Question 21

When will the engine bleed air valves automatically close?

Answer 21

• Fire handle pulled
• start/shutdown
• overtemp/pressure
• ground pneumatic

Question 22

Describe two ways of setting the landing altitude.

Answer 22

Manually or through the FMC

Question 23

Using the manual method, where will you find the CAB ALT display?

Answer 23

EICAS

Question 24

The cargo fire procedure calls for setting a landing altitude of 8000 feet.
How would you do that?
Where do you find the position of the outflow valves?

Answer 24

• Select LDG ALT switch to manual and set the landing altitude
• Position of valves is indicated on the EICAS