Air Cond Systems

Question 1

How does Hot Bleed air enter the PACK?

Answer 1

Through Pack flow control valve

Question 2

What happens in the PACK?

Answer 2

2 heat exchanges (ram air inlet and outlet flaps) and an air cycle machine produce cooler air, sub zero temps can be achieved. Bypass valve allows warmer air to be mixed, bypasses ACM and last heat exchanger.

Question 3

What controls the valves

Answer 3

The ACS controller

Question 4

What happens to the Ram air inlet during take-off?

Answer 4

Closes

Question 5

Where is the air from PACKs sent?

Answer 5

To mixing unit

Question 6

What is shown on ECAM for PACKS?

Answer 6

PACK flow (Valve pos)
Comp outlet temp
Bypass valve position
Pack outlet temp

Question 7

How many outputs from the Mixing Unit?

Answer 7

3
Cockpit
Fwd Cabin
Aft Cabin

Question 8

How many ACS controllers?

Answer 8

2
each has 2 lanes
One active and one stby
Both fail PACK lost

Question 9

How is warm air added after the mixing unit?

Answer 9

Via 3 Trim Air Valves via hot air valve, regulates and acts as a shut-off valve.

Question 10

Where is Hot air for the trim system taken?

Answer 10

Downstream from the Pack Valves so if they are closed then no trim air.

Question 11

Which ACS controls which Trim air?

Answer 11

1 controls Hot Air Valve and Trim air for Cockpit

2 Controls FWD and AFT cabin

Question 12

What are the Cabin Fans?

Answer 12

Recirc fans, take air back to mixing unit, no indication of these. Can switch off on OHP

Question 13

On ground with APU bleed on which PACKS are supplied?

Answer 13

Both, via the Xbleed

Question 14

What is the 12 o clock position on the zone temperature knobs?

Answer 14

24deg

Question 15

When do the PACK valves close during start?

Answer 15

When ENG Mode selector to IGN/Start. Will open again after 30sec if no start.

Question 16

When will PACK valves open after start?

Answer 16

30sec or when mode switch to normal. APU will supply the PACKs

Question 17

What temp is each increment on the temperature selctors?

Answer 17

2deg

18-30deg

Question 18

Can you get low pressure ground conditioning unit?

Answer 18

Yes, air goes into the mixing unit.

Question 19

What happens to PACK flow valve if overtemp?

Answer 19

Automatically closes.

Question 20

What cabin Diff PX do you need for RAM air to supply?

Answer 20

Less than 1 psi

Question 21

How are the cargo compartments heated?

Answer 21

Ambient air from cabin via Inlet Isolation Valve. Exits via Extraction Fan or via an isolation valve if there is diff px. Outlet Isolation Valve
Can have Trim air on some aircraft.

Question 22

How is Cargo heating controlled?

Answer 22

Automatically via the Cargo Ventilation Controller, does both FWD and AFT

Question 23

How many Ventilation systems are there?

Answer 23

2
Lavatory and Galley
Avionics

Question 24

What happens in the Lavatory Galley Vent system?

Answer 24

Completely automatic
Extraction Fan takes air from them and puts it overboard.
No Controls or indications

Question 25

Does the Battery Vent system have any controls or indications?

Answer 25

No

Question 26

What is the Avionics Ventilation System?

Answer 26

Cool air to Avionics Compartment Flight instruments CB panels

Question 27

What fans are involved in the Avionics Ventilation System?

Answer 27

Blower and Extractor Fans, Controlled by an Avionics Equipment Ventilation Controller

Question 28

Where can you see Avionics Vent information?

Answer 28

On the Cab Press ECAM. VENT INLET OUTLET, normally white

Question 29

Where is air taken for the Avionics Vent System?

Answer 29

From a Skin Air Inlet valve, out via Skin Air Extract. Both open is OPEN CIRCUIT config. Inlet on left outlet right.

Question 30

When do the Skin Air Valves close?

Answer 30

When the skin temperature is low enough. Closed Circuit Configuration.

Question 31

What is the intermediate configuration?

Answer 31

A small flap will open on the Skin Outlet valve if Skin Temp is too high in flight.

Question 32

What is the Closed Circuit Configuration?

Answer 32

Air is being cooled via a skin air heat exchanger. To cool avionics. Air is recirculated

Question 33

Fault on the Blower light, what will happen?

Answer 33

Override Blower, Shuts off fan and allows air in from air conditioning duct.

Question 34

Fault in Extract, what will happen?

Answer 34

Override Extract, Allows air in from the Air Cond system.

Question 35

What happens if smoke in the Avionics Vent system?

Answer 35

Both FAULT lights. Closes Skin heat exchanger, closes blower fan, opens small vent in skin outlet valve and allows Air Cond air into the system.