Enviromental system part 2

Hot compressor bleed air operates the conditioned air system on some turbine aircraft, cold air supplied by the. hot air mixing valve. vapor cycle air conditioning. air cycle air conditioning.

The purpose of the airflow metering aneroid assembly found in oxygen diluter demand regulators is to. regulate airflow in relation to oxygen flow when operating in emergency or diluter demand positions. regulate airflow in relation to cabin altitude when in diluter demand position. automatically put the regulator in emergency position if the demand valve diaphragm ruptures.

An aircraft pressurization cycle is normally considered to be. one complete series of events or operations that recur regularly. one take off and one landing. when the fuselage reaches its maximum pressure differential one time.

Composite oxygen bottles that conform to DOT-E-8162 have a service life of. 5 years or 5,000 filling cycles whichever occurs first. 10 years or 5,000 filling cycles whichever occurs first. 15 years or 10,000 filling cycles whichever occurs first.

(Refer to Figure 13.) Determine what unit is located immediately downstream of the expansion valve in a freon refrigeration system. Condenser. Compressor. Evaporator coils.

How often should standard weight high-pressure oxygen cylinders be hydrostatically tested?. Every 5 years. Every 4 years. Every 3 years.

A small amount of water in a vapor cycle cooling system can freeze. in the receiver-dryer and stop the entire system operation. in the expansion valve and stop the entire system operation. but the system is designed to continue operation.

If a high-pressure oxygen cylinder is to be installed in an airplane, it must meet the specifications of the. aircraft manufacturer or the cylinder manufacturer. Department of Transportation. National Transportation Safety Board or the Standards of Compressed Gas Cylinders.

The operation of an aircraft combustion heater is usually controlled by a thermostat circuit which. alternately turns the fuel on and off, a process known as cycling. meters the amount of fuel continuously entering the heater and therefore regulates the heater's BTU output. regulates the voltage applied to the heater's ignition transformer.

In a gaseous oxygen system, which of the following are vented to blow out plugs in the fuselage skin?. Pressure relief valves. Filler shutoff valves. Pressure reducer valves.

In a high-pressure oxygen system, if the pressure reducer fails, what prevents high-pressure oxygen from entering the system downstream?. Check valve. Pressure relief valve. Manifold control valve.

What controls the operation of the cabin pressure regulator?. Cabin altitude. Bleed air pressure. Compression air pressure.

If oxygen bottle pressure is allowed to drop below a specified minimum, it may cause. the pressure reducer to fail. the automatic altitude control valve to open. moisture to collect in the bottle.

What is the condition of the refrigerant as it enters the evaporator of a vapor-cycle cooling system?. High-pressure liquid. Low-pressure liquid. High-pressure vapor.

What component in a vapor-cycle cooling system would most likely be at fault if a system would not take a freon charge?. Expansion valve. Condenser. Receiver-dryer.

A pressurization controller uses. bleed air pressure, outside air temperature, and cabin rate of climb. barometric pressure, cabin altitude, and cabin rate of change. cabin rate of climb, bleed air volume, and cabin pressure.

When servicing an air conditioning system that has lost all of its freon, it is necessary to. check oil and add as necessary, evacuate the system, relieve vacuum, and add freon. check oil and add as necessary, evacuate the system, and add freon. check oil and add as necessary, and add freon.

If the liquid level gauge in a vapor-cycle cooling system indicates a low freon charge, the system should. be operated and a pressure check performed. be operated for a period of time to reach a stable condition and then the freon level rechecked. not be operated until freon and oil have been added.

Which oxygen system employs a regulator that operates only when the user inhales?. Continuous-flow system. Emergency-flow system. Demand-flow system.

(Refer to Figure 14.) One hour after an oxygen system was charged for a leakage check, the oxygen pressure gauge read 460 psi at 63°F; 6 hours later the temperature was 51°F. (A 5 psi change is the maximum allowable in a 6-hour period.) What pressure gauge readings would be acceptable to remain within the allowable limits?. 445 to 450 psi. 446 to 450 psi. 455 to 460 psi.

Which section of a turbine engine provides high pressure bleed air to an air cycle machine for pressurization and air conditioning?. Low or high pressure compressor. Compressor inlet. C-D inlet compressor duct.

In an operating vapor-cycle cooling system, if the two lines connected to the expansion valve are essentially the same temperature, what does this indicate?. The system is functioning normally. The expansion valve is not metering freon properly. The compressor is pumping too much refrigerant.

How can it be determined that a vapor-cycle cooling system is charged with the proper amount of freon?. Air bubbles in the sight glass disappear. The compressor loads up and RPM decreases. Air bubbles appear in the sight glass.

What is the main cause of contamination in a gaseous oxygen system?. Moisture. Dust. Nitrogen.

Oxygen used in aircraft systems. is at least 99.5 percent pure and is practically water free. is at least 99.5 percent pure and is the same as hospital-quality oxygen. contains a higher level of water vapor than hospital-quality oxygen.

Which is considered a good practice concerning the inspection of heating and exhaust systems of aircraft utilizing a jacket around the engine exhaust as a heat source?. Supplement physical inspections with periodic operational carbon monoxide detection tests. All exhaust system components should be removed periodically, and their condition determined by the magnetic-particle inspection method. All exhaust system components should be removed and replaced at each 100-hour inspection period.

The function of an expansion valve in a freon cooling system is to act as a metering device and to. reduce the pressure of the gaseous freon. increase the pressure of the liquid freon. reduce the pressure of the liquid freon.

Frost or ice buildup on a vapor-cycle cooling system evaporator would most likely be caused by. the mixing valve sticking closed. moisture in the evaporator. inadequate airflow through the evaporator.

The point at which freon flowing through a vapor-cycle cooling system gives up heat and changes from a gas to a liquid is the. condenser. evaporator. expansion valve.

A contaminated oxygen system is normally purged with. oxygen. compressed air. nitrogen.

Turbine engine air used for air conditioning and pressurization is generally called. compressed air. ram air. bleed air.

The purpose of the dump valve in a pressurized aircraft is to relieve. all positive pressure from the cabin. a negative pressure differential. pressure in excess of the maximum differential.

On some cabin pressurization systems, pressurization on the ground is restricted by the. main landing gear operated switch. cabin pressure regulator. negative pressure-relief valve.

What component might possibly be damaged if liquid refrigerant is introduced into the low side of a vapor-cycle cooling system when the pressure is too high or the outside air temperature is too low?. Compressor. Condenser. Evaporator.

The evacuation of a vapor-cycle cooling system removes any water that may be present by. drawing out the liquid. raising the boiling point of the water and drawing out the vapor. lowering the boiling point of the water and drawing out the vapor.

For use in pressurized aircraft, which is generally the least complicated and requires the least maintenance?. Chemical oxygen generator systems. High-pressure oxygen systems. Low-pressure oxygen systems.

To be eligible for recharging, a DOT 3HT oxygen cylinder must have been hydrostatically tested every three years and be retired from service after. 24 years or 4,380 filling cycles. 15 years or 10,000 filling cycles. 10 years or 5,000 filling cycles.

If the cabin rate of climb is too great, the control should be adjusted to cause the. outflow valve to close slower. outflow valve to close faster. cabin compressor speed to decrease.

The cabin pressure control setting has a direct influence upon the. outflow valve opening. pneumatic system pressure. inflow valve opening.

The component that determines the pressure level in the cabin is the cabin air pressure. shut-off valve. safety valve. outflow valve.

The purpose of a subcooler in a vapor-cycle cooling system is to. augment the cooling capacity during periods of peak demand. aid in quick cooling a hot aircraft interior. cool the freon to prevent premature vaporization.

How is the cabin pressure of an aircraft maintained in flight?. By controlling the rate of the air flowing into the cabin. By inflating the door seals and recirculating the conditioned cabin air. By controlling the rate of the air flowing out of the cabin.

What test is used to determine the serviceability of an oxygen cylinder?. Pressure test with manometer. Pressure test with nitrogen. Pressure test with water.

When Refrigerant-12 is passed over an open flame, it. changes to methane gas. is broken down into its basic chemical elements. changes to phosgene gas.