Environmental system Flashcards
Where does the warm air come from that is used to heat the cabin of a large jet transport aircraft?
Warm engine compressor bleed air is used
Where is the first place the hot compressor bleed air gives up some of its heat in an air cycle cooling system?
In the primary heat exchanger
Why must air-cycle air conditioning systems incorporate a water separator?
The rapid cooling of the air expansion turbine causes moisture to condense in the form of fog. This moisture is trapped in the moisture separator before the air is released into the cabin
How is the temperature of the air produced by an air cycle cooling system controlled?
By a temperature controlled valve which mixes hot engine compressor bleed air with cold air from expansion turbine
How is cabin pressure controlled in a pressurized aircraft?
More pressure than is needed pumped into the aircraft cabin, and the pressure controller modulate The outflow valve to maintain the correct pressure in the cabin
What Is the function of the cabin outflow valve on a pressurized aircraft?
The cabin outflow valve, which is controlled by the pressure controller, maintains the correct amount of pressure inside the cabin
What is the function of the cabin pressure safety valve on a pressurized aircraft?
The cabin pressure safety valve prevents cabin pressure from exceeding the maximum allowable differential pressure
Why must pressurized aircraft have a negative pressure releif valve?
The structure of an aircraft cabin is not designed to tolerate the inside pressure being lower than the outside pressure
What keeps the cabin of a pressurized aircraft from being pressurized when the aircraft is on the ground?
A squat switch on the landing gear holds the safety valve open when the aircraft is on the ground
