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18 Cards in this Set
- Front
- Back
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What are the 5 things we do to air before we use it to pressurise it? |
Cool it, heat it, humidity control, mass flow control,distribution |
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What are the three methods of reducing moisture content of the air to the cabin? (Water seperation) |
Coalescer/diffuser type, Coalescer/bag type and the swirl vane type |
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What is meant by trim air? |
low-pressure, high-temperature air tapped off the A/C pack upstream of the TCV(engine bleed air) |
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What happens at 8000 ft? |
Hypoxia, oxygen to air ratio is the same but the body must work harder to inhale |
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What happens at 10000ft? |
Air density and temperature decreases to a level that adversely effects the human body |
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What happens at 14,000ft |
Oxygen masks deploy |
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What are the three air cycle machines? |
Tubocompressor, brake turbine, and the turbo fan |
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How does a turbocompressor work? |
Hot charge air is passed through and cooled by the precooler, then through the compressor stage of the ACM where it is compressed causing it to heat up. I then exits to the intercooler matrix where it is cooled again, then the turbine stage where it's further cooled by making it work spinning the ACM, then allowing it to expand into a larger cross section pipe, cooling it further |
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How are the brake turbine and turbo fan better than the turbo compressor? |
More efficient and save weight by less components |
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What advantage does the turbo fan have? |
Draws cooling ram air across the heat exchanger so can work while stationary on the ground |
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How does a vapour cycle system work? |
The vapour cycle system works by using a refrigerant in a sealed pressurised system to absorb heat when changing from a liquid to a gas |
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How is pressurisation controlled? |
Standby mode, auto mode, and manual mode. Outwards pressure relief valve prevents over pressure (8.5psid), negative pressure relief valve (-0.5psid), dump valves (operated by landing gear, ditching valves (all valves below water level will seal in the case of water ditching ) |
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Which ECS pack mainly feeds the flight deck? |
The left hand ECS supplies the majority of the air to the cockpit |
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How much air can be recycled? |
As much as 40% of the cabin air can be recirculated back to the main distribution manifold |
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There are 3 modes of pressurisation what are they? |
Unpressurised mode (cabin altitude remains the same as flight altitude), isobaric mode (manual setting of up to 8000ft), constant-differential pressure mode (takes control if cabin pressure to ambient pressure goes beyond specific limits) |
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What are the values for the cabin altitude rate of climb and descent? |
Maximum climb rate of 500ft per min, maximum descent of 300ft per min |
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What methods of pressure indication are there on the flight deck? |
Cabin altitude gauge, cabin rate of climb, differential pressure gauge, dual gauge |
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What special safety requirements are needed for aircon/pressurisation ground runs |
At least three men are required |
