Air Conditioning - Boeing 757/767

Question 1

What does the Cabin Altitude AUTO INOP light indicate?

Answer 1

Both Auto 1 and 2 are inoperative or manual mode is selected

Question 2

What does the Pack Reset switch do when pushed?

Answer 2

Resets and overheated pack if the pack has cooled to a temperature below the overheat level.

Question 3

When a Pack Control selector is positioned to STBY N, what is the outlet temperature of the pack inflight?

Answer 3

A constant, moderate temperature (40* inflight)

Question 4

What can cause a Pack Off light to illuminate?

Answer 4

Pack valve is closed.

Question 5

What cabin temperature do the packs attempt to maintain if the Trium Air switch is selected OFF?

Answer 5

Maintain all compartments at an average temperature of 75* (24C)

Question 6

What is the purpose of trim air?

Answer 6

Hot trim air from the bleed system is added to meet the zone temperature requirements.

Question 7

What does the Trim Air OFF light indicate?

Answer 7

Trim Air Switch is OFF.

Question 8

What can cause a Compartment Temperature INOP light to illuminate?

Answer 8

Zone air overheat or fault in the zone temperature controller.

Question 9

What crew action illuminates the AUTO INOP light on the Cabin Altitude Controller?

Answer 9

Selecting MAN position on the cabin Altitude Control Panel.

Question 10

What happens when an automatic control system fault or a pack outlet overheat is detected?

Answer 10

The pack continues to operate in an uncontrolled, degraded condition, requiring crew action.

Question 11

What are the expected pressurization limits for climbs and descents with Auto Rate knob selected to the index mark?

Answer 11

Climb - 500 fpm Descent - 300 fpm

Question 12

(757) Which condition automatically opens the overboard exhaust valve?

Answer 12

The recirculation fan fails.

Question 13

What condition activates the ground call horn?

Answer 13

Insufficient equipment cooling airflow detected on the ground.

Question 14

(757) One forward equipment cooling system supply fan operates at a time. What starts the alternate fan?

Answer 14

Selecting the alternate equipment cooling switch to ALTN.

Question 15

(757) what occurs if ALTN is selected on the alternate equipment cooling switch?

Answer 15

Activates the alternate supply fan and opens the overboard exhaust valve if required.

Question 16

(RR) With the high altitude landing switch on, what cabin altitude annunciates the cabin altitude light and EICAS message?

Answer 16

14,650 ft

Question 17

(767). What condition annunciates the equipment cooling valve light?

Answer 17

Equipment cooling valves are not in the commanded position.

Question 18

(767) What does the equipment cooling OVHT light indicate?

Answer 18

High temperature or low airflow in the equipment cooling system.

Question 19

(767) What does the equipment cooling SMOKE light indicate?

Answer 19

Smoke in the equipment cooling system.

Question 20

(767) Selecting the equipment cooling selector to OVRD results in what equipment cooling actions?

Answer 20

Open smoke override valve in positions equipment cooling system for reverse airflow.

Question 21

What cabin altitude extinguish is the cabin altitude light and EICAS message?

Answer 21

Cabin altitude below 8500 feet

Question 22

What does a pack off light in associated EICAS message indicate?

Answer 22

Respective pack valve closed

Question 23

(RR) With the high altitude landing switch off, what cabin altitude annunciate the cabin altitude light and EICAS message?

Answer 23

10,000 ft

Question 24

What could cause compartment temperature INOP lights to illuminate?

Answer 24

Trim air switch is off

Question 25

During automatic temperature control, which temperature zone controls the output temperature of the air conditioning packs?

Answer 25

The zone requiring the coolest air

Question 26

What altitude setting is selected on the landing altitude indicator during cockpit preparation?

Answer 26

Landing altitude in feet

Question 27

What occurs if the cabin altitude mode selector is set to AUTO 1 and it fails?

Answer 27

Control is automatically switched to AUTO 2 controller