Systems 21 AC/Press/Vent

Question 1

When will the Emergency Ram Air inlet open?

Answer 1

RAM AIR push button pressed
Outflow valve is under automatic control
Differential pressure is less than 1 psi.

Question 2

What is the temperature selectable range for Air Conditioning?

Answer 2

18° to 30° C

Question 3

When is the Air Inlet Flap closed during takeoff and landing?

Answer 3

Takeoff:
Closes when take of power is set and main landing gear strut are compressed.

Landing:
As soon as the main landing gear struts are compressed and speed above 70kt.
Opens again 20s after speed gets below 70kts.

Reason: FOB doesn’t enter the inlet

Question 4

When does the system deliver higher flow, regardless of the PACK FLOW selector selection?

Answer 4

One pack operation and APU i supplying bleed air.
The system delivers normal flow if the flight crew selects LO flow and the temperature demand cannot be satisfied.

Note: On ground with both engines running, the normal flow is limited to 85 % (NEO).

Question 5

When is the Pack Flow valve open during normal operation?

Answer 5

When the PACK Push button is pressed and not any of following:
- Upstream pressure below minimum
- Compressor outlet overheat
- Engine start sequence:
1. If the crossbleed valve is closed, the valve located on the starting engine
side immediately closes, when the ENG MODE selector is set to IGN (or
CRK)
2. It remains closed on the starting engine side (provided the crossbleed valve
is closed) when:
- The ENG MASTER lever is set to ON (or ENG MAN STAR pb-swT is set
to ON)
- The start valve is open
- N2 < 50%.
Note: If the crossbleed valve is open at engine start, both pack flow
control valves close.
3. On ground, reopening of the valves is delayed for 60 s to avoid a
supplementary pack closure cycle during second engine start.
- FIRE pb, of the engine on the related side, is pressed
- Ditching is selected.

Question 6

How does the Cabin Pressurization work during normal operation? (4 general functions)

Answer 6

• Ground function : Fully opens the outflow valve on ground
• Prepressurization : During takeoff, increases cabin pressure to avoid a surge in cabin pressure
  during rotation
• Pressurization in flight : Adjusts cabin altitude, and rate of change to provide passengers with a
  comfortable flight
• Depressurization : After touchdown, gradually releases residual cabin overpressure before the
  ground function fully opens the outflow valve.

Question 7

The Cabin Pressure Controllers receives data from 4 sources, which?

Answer 7

Air Data Inertial Reference System (ADIRS), the Flight Management and Guidance Computer (FMGC), the Engine Interface Unit (EIU), and the Landing
Gear Control Interface Unit (LGCIU).

Question 8

The is the Outflow vale located?

Answer 8

The outflow valve is on the right-hand side of fuselage, behind the aft cargo compartment and below
the flotation line.

Question 9

Where are the Pneumatic Safety Valves located?

Answer 9

They are located on the rear pressure bulkhead, above the flotation line.

Question 10

When is the Avionics Ventilation in ground operation?

Answer 10

When all are true:
* On Ground
* Throttle not at TO
* NEO: Avionics Duct Temp >= 40°C
* CEO: Skin Temperature:
+12 °C (53 °F), temperature increasing, or
+9 °C (48 °F), temperature decreasing.