Air Conditioning/Packs

Question 1

The Packs are supplied

Answer 1

by the 10th Stage

Question 2

Each pack creates cold air by operation of:

Answer 2

An air cycle machine

Question 3

How does air from the packs enter the cabin?

Answer 3

Conditioned air through the floor level vents; cold air through the gasper vents

Question 4

Cold air from each pack is routed to:

Answer 4

The onside gasper vents in the cabin and underfloor to the main avionics bay; the right pack also supplies the cold air gasper vents in the cockpit

Question 5

Pack operation is enhanced while on the ground by:

Answer 5

A bleed-air ejector in each heat exchanger air plenum

Question 6

Pack low temperature output is limited:

Answer 6

Automatically by a low-limit temperature sensor and valve assembly

Question 7

The packs are located:

Answer 7

In the AFT Equipment Bay

Question 8

The Packs operate in high mode when:

Answer 8

The 10th Stage SOVs are closed(APU or external air supply) while on the ground; or when a pack is automatically shut down for over-pressure or over-temperature or is selected off while airborne (APU or 10th stage air bleed-air supply is in use)

Question 9

In case of pack shutdown, the remaining pack;

Answer 9

Automatically switches to high mode if the pack shutdown was due to over-pressure or over-temperature, or when the affected PACK switchlight is selected OFF

Question 10

The PACK HI TEMP caution EICAS message results in:

Answer 10

Closing of the related Pack valve

Question 11

The PACK NOT OFF caution EICAS message is shown if:

Answer 11

Temperature at the related pack outlet is excessive while the pack valve is commanded closed

Question 12

While in STBY mode, zone temperature is controlled by reference to the:

Answer 12

Related duct temperature sensor

Question 13

While in MAN mode, zone temperature is:

Answer 13

Accomplished by direct control of the temperature control valve via the temperature selector knob

Question 14

While in NORM mode, selecting a temperature that differs by more than 3° from the existing zone temperature causes:

Answer 14

The related pack to produce conditioned air at either 35°F or 180°F duct temperature, as appropriate

Question 15

Ram air into the pressure vessel enters through the:

Answer 15

inlet at the bottom of the vertical stabilizer

Question 16

The Ram air valve is:

Answer 16

Controlled by the RAM-AIR Switchlight

Question 17

Ram-Air enter the pressure vessel via:

Answer 17

The Left pack conditioned air duct

Question 18

Ram air use requires:

Answer 18

at least 250 KIAS

Question 19

The CKPT HEAT switch controls:

Answer 19

An electric fan and heater for foot warmer and windshield defogging

Question 20

Air distribution to the cabin and the cockpit is as follows:

Answer 20

Left pack conditioned air: 40% flows to the cabin, 60% to the cockpit; right pack conditioned air: 100% flows to the cabin

Question 21

The under-floor avionics bay is cooled by the:

Answer 21

Cold air from each pack and by exhaust air from the cockpit electronic displays and instruments

Question 22

The DISPLAY COOL FAIL status EICAS message indicates:

Answer 22

One or more EFIS or EICAS display fans have failed

Question 23

The avionics cooling fans begin operation when:

Answer 23

AC power is applied to the aircraft

Question 24

Cabin temperature is displayed on:

Answer 24

ED2 in degrees celsius only