Packs

Question 1

Pack valve functions are?

Answer 1

Shut off, pressure control and hence flow control

Question 2

Packs PB “ON” means that

Answer 2

Pack valve is opened if the opening conditions are met or encountered

Question 3

Air conditioning packs are installed

Answer 3

One in each landing gear fairing

Question 4

Which packs is the primary supplier of cockpit air?

Answer 4

Left

Question 5

What happens to the excess air from the left pack?

Answer 5

It’s used to supply the cabin

Question 6

What is the electrical supply for the packs?

Answer 6

DC ESS BUS

Question 7

Pack valves are

Answer 7

Pneumatically operated and electronically controlled

Question 8

Air flow level is controlled

Answer 8

Automatically, according to the bleed air pressure
Manually, by a single/high PB

Question 9

The selection of airflow “normal/high” from packs is

Answer 9

Manual in any case

Question 10

What happens when “pack flow” pb is “IN”, “HIGH” illuminates

Answer 10

Both pack valves are controlled to allow a higher regulated pressure (30 instead of 22 PSI)

Question 11

Provided that the relative pack valves are not closed, the cooling are running

Answer 11

Automatically, on the ground
Automatically, in flight speed below 150kts and landing gear is is retracted for less than 10 minutes

Question 12

The compartment temperature selector

Answer 12

When in manual, the temp CTL valve is directly controlled by the comp temperature selector

When in Auto the Temp CTL is controlled by the comp temp selector through electronic temp controller

Question 13

When the the temp SEL PB in AUTO, the electronic temperature controller computes temperature control valve position taking into account

Answer 13

Duct outlet temperature
Associated compartment temperature
and A/C skin temperature

Question 14

The compartment temp selector is operative

Answer 14

In automatic and manual mode

Question 15

TEMP SELECTOR PB IN MANUAL MODE:

Answer 15

OVERHEAT ALARM IS NOT INHIBITED

Question 16

THE “COMPT TEMP” INDICATOR DISPLAYS:

Answer 16

THE COMPARTMENT AND DUCT TEMPERATURES OF THE SELECTED SIDE

Question 17

THE RECIRCULATION FANS ARE USED TO:

Answer 17

RECIRCULATE A PART OF THE CABIN AIR, TO INCREASE FRESH AIR SUPPLY

Question 18

ON GROUND, THE AIR SUPPLIED TO THE AIR CONDITIONING SYSTEM MAY COME FROM

Answer 18

ENGINES OR A GROUND CONDITIONING UNIT

Question 19

PACK VALVE FAULT MEANS:

Answer 19

ACTUAL VALVE POSITION DISAGREE WITH THE SELECTED POSITION &
OVERHEAT DOWNSTREAM OF THE COMPRESSOR (T +204°C\393°F)

Question 20

IF A PACK VALVE IS CLOSED OR INOPERATIVE:

Answer 20

THE OTHER PACK SUPPLIES BOTH COMPARTMENTS (COCKPIT, CABIN) THROUGH THE
MIXING CHAMBER

Question 21

WHEN THE BLEED VALVES ARE SELECTED “ON” PACK VALVE PB PRESSED IN:

Answer 21

PACK 1 VALVE OPENS IMMEDIATELY, PACK 2 VALVE OPENS UP AFTER 6 SEC DELAY

Question 22

IF THE RELATED ELECTRICAL SUPPLY (OR AIRFLOW) IS LOST, THE PACK VALVES:

Answer 22

ARE SPRING LOADED CLOSED

Question 23

IN CASE OF PACK OVERHEAT DOWNSTREAM OF THE COMPRESSOR

Answer 23

THE PACK VALVE ON THE FAULTY SIDE CLOSES

Question 24

IN CASE OF DUCT OVERHEAT DOWNSTREAM OF THE MIXING CHAMBER

Answer 24

NO PACK VALVE CLOSES

Question 25

TEMP SELECTOR OVHT CAUTION IS TRIGGERED WHEN:

Answer 25

DUCT TEMPERATURE EXCEEDS 92°C

Question 26

WHAT IS THE MEANING OF RECIRCULATION FAN “FAULT” LIGHT?

Answer 26

FAN RPM TOO LOW
FAN MOTOR OVERHEAT