AIRCOND SYSTEM

(8498) At which component in an air-cycle cooling system does air undergo a pressure and temperature drop?. At which component in an air-cycle cooling system does air undergo a pressure and temperature drop?. Primary heat exchanger. Refrigeration bypass valve.

(8543) When checking a freon system, a steady stream of bubbles in the sight gauge indicates the charge is. high. correct. low.

(8548) (1) Usually bleed air from a gas-turbine engine compressor can be safely used for cabin pressurization. (2) Independent cabin condition air machines (air cycle machine) can be powered by bleed air from an aircraft turbine engine compressor. Regarding the above statements,. only No. 1 is true. only No. 2 is true. both No. 1 and No. 2 are true.

(8503) The cabin pressure of an aircraft in flight is maintained at the selected altitude by. controlling the air inflow rate. inflating door seals and recirculating conditioned cabin air. controlling the rate at which air leaves the cabin.

(8504) What controls the operation of the cabin pressure regulator?. Cabin altitude. Bleed air pressure. Compression air pressure.

(8505) The basic air-cycle cooling system consists of. a source of compressed air, heat exchangers, and a turbine. heaters, coolers, and compressors. ram air source, compressors, and engine bleeds.

(8506) 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.

(8585) Which of the following are characteristic of a chemical or solid state oxygen system? 1. An adjustable oxygen release rate. 2. A volume storage capacity about three times that of compressed oxygen. 3. The system generators are inert below 400°F even under severe impact. 4. A distribution and regulating system similar to gaseous oxygen systems. 2 & 3. 3 & 4. 1 & 2.

(8507) 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.

(8508) 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.

(8509) When charging a vapor-cycle cooling system after evacuation, the low-pressure gauge fails to come out of a vacuum. What is indicated?. Blockage in the system. The expansion valve failed to close. The compressor is not engaging.

(8510) 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.

(8511) 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.

(8512) What test is used to determine the serviceability of an oxygen cylinder?. Pressure test with manometer. Pressure test with nitrogen. Pressure test with water.

(8513) How often should standard weight high-pressure oxygen cylinders be hydrostatically tested?. Every 5 years. Every 4 years. Every 3 years.

(8514) 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.

(8515) What type of oxygen system uses the rebreather bag-type mask?. Diluter demand. Continuous flow. Demand.

(8497) 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.

(8517) Hot compressor bleed air operates the conditioned air system on some turbine aircraft, cold air supplied by the. hot air mixing valve. sonic airflow control unit. ram air cycle cooling unit.

(8518) 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.

(8519) The main cause of contamination in gaseous oxygen systems is. moisture. dust and other airborne particulates. other atmospheric gases.

(8520) Where does the last stage of cooling in an air-cycle air-conditioning system occur?. Refrigeration unit compressor. Secondary heat exchanger. Expansion turbine.

(8521) 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.

(8522) The point at which freon flowing through a vapor-cycle cooling system absorbs heat and changes from a liquid to a gas is the. condenser. evaporator. expansion valve.

(8523) How is the cabin pressure of a pressurized aircraft usually controlled?. By a pressure-sensitive switch that causes the pressurization pump to turn on or off as required. By an automatic outflow valve that dumps all the pressure in excess of the amount for which it is set. By a pressure-sensitive valve that controls the output pressure of the pressurization pump.

(8524) 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.

(8525) 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.

(8526) The cabin pressure control setting has a direct influence upon the. outflow valve opening. pneumatic system pressure. inflow valve opening.

(8499) In a freon vapor-cycle cooling system, where is cooling air obtained for the condenser?. Turbine engine compressor. Ambient air. Pressurized cabin air.

(8527) The function of the evaporator in a freon cooling system is to. liquefy freon in the line between the compressor and the condenser. lower the temperature of the cabin air. transfer heat from the freon gas to ambient air.

(8528) What is the purpose of a mixing valve in a compressor bleed air air-conditioning system?. Control the supply of hot, cool, and cold air. Distribute conditioned air evenly to all parts of the cabin. Combine ram air with conditioned air.

(8529) What component of a pressurization system prevents the cabin altitude from becoming higher than airplane altitude. Cabin rate-of-descent control. Negative pressure relief valve. Positive pressure relief valve.

(8501) Turbine engine air used for air-conditioning and pressurization is generally called. compressed air. ram air. bleed air.

(8530) 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.

(8531) 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.

(8532) The position of the thermostatic expansion valve in a vapor-cycle cooling system is determined by temperature and pressure of the. freon entering the evaporator. air in the outlet of the condenser. freon in the outlet of the evaporator.

(8533) The function of the condenser in a freon cooling system is to. transfer heat from the freon gas to ambient air. change liquid freon into a gas before it enters the compressor. transfer heat from the cabin air to the liquid freon.

(8534) 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.

(8535) Which prevents a sudden loss of pressurization in the event that there is a loss of the pressurization source?. Firewall shutoff valve. Cabin pressure outflow valve. Delivery air duct check valve.

(8500) What is ventilating air used for on a combustion heater. Provides combustion air for ground blower. Carries heat to the places where needed. Provides air required to support the flame.

(8576) (1) Oxygen used in aircraft systems is at least 99.5 percent pure and is practically water free. (2) Oxygen used in aircraft systems is 99.5 percent pure and is hospital quality. Regarding the above statements. only No. 1 is true. both No. 1 and No. 2 are true. neither No. 1 nor No. 2 is true.

(8539) After cleaning or replacing the filtering element in a combustion heater fuel system, the system should be pressurized and. all connections checked for leaks. the fuel filter bypass valve reset to the filter position. a sample of fuel taken downstream from the filter to ensure proper operation of the new filtering element.

(8540) 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.

(8536) 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.

(8541)The air-cycle cooling system produces cold air by. extracting heat energy across a compressor. passing air through cooling coils that contain a refrigerant. extracting heat energy across an expansion turbine.

(8546) 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.

(8542) (Refer to Figure 13.) Determine what unit is located immediately downstream of the expansion valve in a freon refrigeration system. Condenser. Compressor. Evaporator coils.

(8544) 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.

(8546) 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.

(8547) The cabin pressurization modes of operation are. isobaric, differential, and maximum differential. differential, unpressurized, and isobaric. ambient, unpressurized, and isobaric.

(8549) 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.

(8550) What unit in a vapor-cycle cooling system serves as a reservoir for the refrigerant. Receiver-dryer. Evaporator. Condenser.

(8555) What is the condition of the refrigerant as it leaves the condenser of a vapor-cycle cooling system?. Low-pressure liquid. High-pressure liquid. High-pressure vapor.

(8554) What is the condition of the refrigerant as it leaves the evaporator of a vapor-cycle cooling system?. Low-pressure liquid. Low-pressure vapor. High-pressure vapor.

(8553) 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.

(8552) 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.