Cabin
Ambient Air
A. CARGO SYSTEMS
b) in FWD and/or AFT cargo compartment (all aircraft, optional):
Ventilation system is based on air suction provided by an extraction fan or by a venturi tube in flight when the pressure difference is sufficient. In the case of temperature regulation, the air enters pressurized and conditioned. The air enters the compartment through one side wall and ceiling and is extracted on the other side. Temperature control is provided on top of the ventilation by adding cold or hot air respectively from the packs or hot air manifold. The hot air supply is controlled by a trim valve which regulates the temperature in the compartment. To decrease the compartment temperature, the cabin ambient air can be mixed with cold air from the packs via a cold air valve. This valve has three positions to adjust the quantity of cooled conditioned air. In the event of smoke detection, the isolation valves, trim air valve, cold air valve are automatically closed and the extraction fan is switched OFF. A cockpit temperature selector and a cockpit cooling mode selector control temperature. It is possible to select temperatures within the range of 5 DEG C and 25 DEG C (41 DEG F and 77 DEG F).
An additional option is available which ensures proper ventilation in the bulk and main cargo
compartments during ground time when respective cargo doors are open.
In the bulk cargo compartment, the basic fan heaters can be controlled by an ON/OFF switch on
the aft compartment servicing panel in order to activate the blowing function when the aircraft is
on ground and the cargo compartment door is fully open. The heating function is deactivated in
this operation.
In the main cargo compartment, this option uses the same ventilation as in flight nevertheless;
the following aircraft conditions and activities are necessary:
. Packs running
. Forward cooling selector in cockpit overhead panel in "NORM" position.
SYSTEMS
A. CARGO SYSTEMS
SYSTEMS
2.4.6. Fire protection:
We consider two airworthiness requirements:
. Class “C” (FAR 25.857(c)):
A class —C“ cargo or baggage compartment is one in which:
1-There is a separate approved smoke detector or fire detector system to givewarning at the pilot or flight engineer station 2-There is an approved built-in fire-extinguishing system controllable from the pilot or flight engineer station 3-There are means to exclude hazardous quantities of smoke, flames or othernoxious gases from any compartment occupied by the crew or passengers
4-There are means to control ventilation and drafts within the compartment sothat the extinguishing agent used can control any fire that may start within the compartment.
5-{Reserved}
To sum up, it is a compartment, which has a smoke detection and an automatic fire extinguishing system and burn through resistant lining.
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本文链接地址：Getting to Grips with Aircraft Weight and Balance(18)
