Air Systems

Question 1

What does the BLEED TRIP OFF (amber) light indicate?

Answer 1

Bleed Trip Sensors have automatically closed the Engine Bleed Air Valve with excessively high engine bleed air temps (254 deg C) or excessively high pressure (220psi) (Sec 2.010 p 5)

Question 2

Conditions permitting, the TRIP RESET switch resets which lights?

Answer 2

Resets the bleed trip condition if the exceedances no longer exist. With Eng Bleed Switches ON valve automatically reopens. Also resets ZONE TEMP or PACK lights. (Sec 2.010 p 5)

Question 3

How does the ISOLATION VALVE operate with its switch in AUTO?

Answer 3

In AUTO the ISOLATION VALVE with close when:

1) both Engine BLEED Air Switches are ON, and
2) both Air Conditioning PACK switches are in AUTO or HIGH

Placing any one of these switches to OFF will automatically open the Isolation Valve

Isolation Valve not affected by APU BLEED Air Switch

(Sec 2.010 p 8)

Question 4

What precautions apply with the APU Bleed Valve when an Engine Bleed Valve is open?

Answer 4

Thrust must be limited to idle when DUAL BLEED light illuminated (Sec 2.010 p 8)

Question 5

When does the DUAL BLEED (amber) light illuminate?

Answer 5

APU Bleed Air Valve open, and

1) Eng 1 Bleed Switch ON, and/or
2) Eng 2 Bleed Switch ON with Isolation Valve open

(Sec 2.010 p 8)

Question 6

What does the WING-BODY OVERHEAT (amber) light indicate?

Answer 6

An overheat has been detected – bleed leak has been detected

(Sec 2.010 p 10)

Question 7

A single pack in high flow mode is capable of maintaining pressurization and acceptable temperatures throughout the aircraft up to what altitude?

Answer 7

Maximum certified ceiling (Sec 2.020 p 2)

Question 8

Which Valve pneumatically modulates to control airflow into the respective Air Conditioning Pack based on air condition demands?

Answer 8

Pack Valves (Sec 2.020 p 3)

Question 9

When does a pack automatically switch to “high air flow?”

Answer 9

Airborne, both PACK Switches in AUTO and ENG Bleed Switches ON, if one PACK or engine fails or PACK is selected to OFF, the remaining PACK automatically switches to high air flow (Sec 2.020 p 4)

Question 10

How do the Recirculation Fan(s) operate with both RECIRC FAN switches in AUTO, and both PACK switches in AUTO?

Answer 10

Both Recirc Fans operate

Sec 2.020 p 9

Question 11

Where do the Air Recirculation Fans draw air from?

Answer 11

Left Recirc Fan pulls in air from the Air Conditioning Distribution Compartment
Right Recirc Fan pulls cabin air through the floor grilles on each side of the passenger cabin.

(Sec 2.020 p 9)

Question 12

What does illumination of a ZONE TEMP (amber) light indicate?

Answer 12

Failure of both primary and standby temp controllers (CONT CAB) or duct overheat (FWD or AFT CAB)

During Master Caution Recall this indicates primary temp controller failure (CONT CAB) or failure of fwd or aft cabin temp controller (FWD or AFT CAB)

(Sec 2.020 pp 12-13)

Question 13

How do you position PACK switches when using external conditioned air?

Answer 13

PACK switches OFF

Sec 2.020 p 15

Question 14

What controls the temperature of conditioned air from an external air source?

Answer 14

External air temp controls – Flight Deck controls are ineffective to control external air temps

(Sec 2.020 p 15)

Question 15

Packs produce air temperature to satisfy which zone?

Answer 15

PACK outlet temp matches the zone with the lowest setting

Sec 2.020 p 11

Question 16

What happens with a failure of the primary Flight Deck zone temperature control?

Answer 16

Automatic switching to standby temp control

Sec 2.020 p 12

Question 17

What temperatures are commanded by positioning by positioning all Zone Temperature Selectors to OFF?

Answer 17

Left Pack = 75 Deg F (24 Deg C)
Right Pack = 65 Deg F (18 Dec C)

Measured at the Pack Temp Sensor

(Sec 2.020 p 13)

Question 18

What provides an Equipment Cooling alert if an overtemperature occurs on the ground?

Answer 18

Crew Call Horn in the nose wheel well

Sec 2.020 p 17

Question 19

What is the purpose of the Overboard Exhaust Valve (OEV)?

Answer 19

Controls quantity of equipment cooling air flowing overboard and has a smoke removal function

(Sec 2.030 p 2)

Question 20

When is the Outflow Valve Position Indicator operational?

Answer 20

Outflow Valve Position Indicator operates regardless of pressurization mode selected

(Sec 2.030 p 6)

Question 21

When does the OFF SCHED DESCENT (amber) illuminate?

Answer 21

If descent is begun without having reached selected altitude

Sec 2.030 p 10

Question 22

How is pressurization controlled with Cabin Pressurization Mode Selector in MAN?

Answer 22

Outflow Valve Position Switch

Sec 2.030 p 12

Question 23

What two warnings use the same aural tone (intermittent horn) when activated?

Answer 23

Cabin Altitude and Takeoff Configuration warning use the same aural tone

(Sec 2.030 p 15)