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dartagnan
3rd Dec 2006, 14:31
hi,

I am a newbie here.i am studing the systems of the 320.

on the 320, what would happen when pack 1 & 2 are out of service.
my book say you have to be below 10'000 feet to "scoop" some air in the cabin.

what about the temperature?

second question:

I have some picture of the system panel of the 320 (or 319), I don't find the hot air valve push button for the back cargo area.

is there a difference between the 320 and the 319 regarding cabin/cargo temperature?

animals must be placed in the back area, due to the hot air valve.
The position of the selector is for 16 degree(placed at 12 o'clock). don't you think it is little be too cold for animals?

Why Airbus, did'nt preselect 24 degree?

Dan Winterland
3rd Dec 2006, 14:45
1. No conditioning and no pressurization. There is no temp contol. It will get pretty cold. Max alt is 10,000' for opening the ram air because the cabin will depressurise once the ram air scoop is open.

2. Rear cargo compartment heating is an option. Its more common on A321s. As for the 319/320 differences, I don't fly the 319 but I doubt there's much of a difference. Only the cabin has rotary temp selectors, the 12 o'clock position is 24 degress, the range being from 18 to 30.

And I don;t think 16 degress is too cold for animals. That's why they have fur coats!

donkeeshot
3rd Dec 2006, 14:50
Hi,

If you have pack 1+2 fault you depressurize the cabin and you must descent 10000 ft. Then when the differential pressure is below 1psi (almost 0) you ventilate the cabin with the Ram Air, it is just air from outside at outside temperature but at least the passengers (and you) can breath.

the control of the cargo temperature is optional, on the right side of the overhead panel;

a type rating soon ?

good luck

donkeeshot
3rd Dec 2006, 14:55
1. No conditioning and no pressurization. There is no temp contol. It will get pretty cold. Max alt is 10,000' for opening the ram air because the cabin will depressurise once the ram air scoop is open.

In the Ram Air you have a check valve. You cannot depressurize with the Ram Air. You depressurize with the outflow valve and when the differetial pressure is below 1 PSI the Air from outside can counter the action of the check valve.

Jet II
3rd Dec 2006, 14:55
There is no temp contol. It will get pretty cold.


Is that strictly true? - the emergency Ram Air Inlet will supply ambient air to the mix manifold, the Trim Air valves in the supply lines after the mix manifold will regulate the temperature to the cabin using the bleed air tapping from the pneumatic system.

idg
3rd Dec 2006, 15:30
But the pack valves will be off and therefore no trim air = very cold!

dartagnan
3rd Dec 2006, 15:36
the ecam action says in case of double failure of the 2 channels computer of the zone control computer (ZCC)to be lower than 10'000 feet before opening the ram air.

as for the temperature,it says the temperature is fixed in case of one failure and no indication if 2 channels fail.
I think the valves stay in the last position, I have no more info.

in a case of dual PACK failure(valve blocked, hot temperature increase), there must be a by pass in the pack system to let engine air to be mixed with the trim valves air and ram air.I have no indication concerning this.

more info would be appreciated before I pass to a next system.