Aircraft systems second 30%

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

What is ventilating air used for on a combustion heater?. provides combustion air for grounnd blower. carries heat to the places where needed. provides air required to support the flame.

In the combustion heater, combustion air system, what prevents too much air from entering the heaters as air pressure increases?. either as combustion air relief valve or a differential pressure regulator. only a differential pressure regulator. only a combustion air relief valve can be used.

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.

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

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 fail to close. the compressor is not engaging.

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.

Frost or ice buildup on a vapor-cycle cooling system evaporator would most likely be caused by. the mixing valve sticking close. moisture in the evaporator. inadecuate airfloe throught the evaporator.

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?. suplemental physical inspections with periodic operacional carbon monoxide detection test. all exhaust system components should be removed periodcally and their conditiondetrmined by the magnetic-particle inspection method. all exhaust system components should be removed and replaced at each 100-hours inspection period.

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

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 freom gas to ambient air.

If the liquid level gauge in a vapor-cycle cooling system indicates a low freon charge, the system should. be operate and pressure check performed. be operated for a period of time to reach stable condition and then the freon level rechecked. no be operated until freon and oil have been added.

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.

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.

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 oulet of evaporator.

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 liquid fren.

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.

When servicing an air-conditioning system that has lost all of its freon, it is necessary to. check oil and add asnecessary evacuate the system relief vaccum and add freon. check oil and add asnecessary evacuate the system and add freon. check oil and add asnecessary and add freon.

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 taking downstream fro the filter to ensure prepper operation of the new filtered element.

The operation of an aircraft combustion heater is usually controlled by a thermostat circuit which. alternatelly turns the fuel on an off, a preccess known as cycle. meters amound of fuel continouslly entering the heater and therefore regulates the heaters BTU output. regulates the voltage applied to the heaters ignitiontransformer.

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

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

What unit in a vapor-cycle cooling system serves as a reservoir for the refrigerant?. receiver-dryer. evaporator. condenser.

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.

The evacuation of a vapor-cycle cooling system removes any water that may be present by. grwing 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.

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.

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.

In what position should the bottle be placed when adding liquid freon to a vapor-cycle cooling system?. vertical with the oulet at the top. horizontal with the oulet to the side. vertical with the oulet at the bottom.

When purging a freon air-conditioning system, it is important to release the charge at a slow rate. What is the reason for the slow-rate discharge?. prevent the large amount of freon from contaminating the sourronding atmosphere. prevent excesive loss of refrigerant oil. prevent condensation from forming and contaminating the system.

When a vapor-cycle cooling system is not in operation, what is an indication that the system is leaking freon?. oil seepage. bubbles in the sight glass. an azone-like odor in the inmediate area.

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 functionong normally. the expansion valve is not metering the freom properly. the compressor is pumping too much refrigerant.

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 colling a hot aircraft interior. cool the freon to prevent premature vaporization.

(1) A small amount of water in a vapor-cycle cooling system can freeze in the receiver-dryer and stop the entire system operation. (2) Water in a vapor-cycle cooling system will react with refrigerant to form hydrochloric acid which is highly corrosive to the metal in the system. only 1 is true. only 2 is true. both 1 and 2 are true.

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

What type of oil is suitable for use in vapor-cycle cooling system?. low viscocity engine oilwith the inhability to absorb water. especial high grade refrigeration oil. highly refined syntetic oil free from impurities with special water absorvers additives.

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

Prior to installation of a pneumatic surface-bonded type deicer boots, on the leading edge of the wing, you should. remove all paint from the area to be recovered by th deicer boot. apply ahesibe to the back of the deicer boot and leading edge of the wing. apply a elastic compound between the boot and wing sking.

Which of the following are found in a laminated integral electrically heated windshield system? 1. Autotransformer. 2. Heat control relay. 3. Heat control toggle switch. 4. 24V dc power supply. 5. Indicating light. 1,2,4,5. 2,3,4,5,. 1,2,3,5.

What is one check for proper operation of a pitot/static tube heater after replacement?. ammeter reading. voltmeter reading. continuity check of system.

What controls the inflation sequence in a pneumatic deicer boot system?. shuttle valve. vacuum pump. distributor valve.

What is the source of pressure for inflating deicer boots on reciprocating engine aircraft?. vane type pump. gear type pump. piston type pump.

Which of the following regulates the vacuum of the air pump to hold the deicing boots deflated when the pneumatic deicing system is off?. distributor valve. pressure regulator. suction relief valve.

What may be used to clean deicer boots?. unleaded gasoline or jet A fuel. naptha. soap and water.

Some aircraft are protected against airframe icing by heating the leading edges of the airfoils and intake ducts. When is this type of anti-ice system usually operated during flight?. continuosly while the aircraft is in flight. in symetric cycles during icing conditions to remove ice as it accumulated. whenever ice conditions are firts encountered or expected to occur.

Which of the following indications occur during a normal operational check of a pneumatic deicer system?. relatively steady readings in the pressure gauge and fluctuating readings on the vacuum gauge. fluctuating readings on the pressure gauge and relatively steady readings on the vacuum gauge. pressure and vacuum gauges will fluctuate as the deicer boots inflate and deflate.

What method is usually employed to control the temperature of an anti-icing system using surface combustion heaters?. thermo cycling switches. thermostats in the cockpit. heater fuel shuttoff valves.

What is the purpose of the oil separator in the pneumatic deicing system?. to protect deicer boots from oil deterioration. to remove oil from air exhausted from the deice boots. to prevent an accumulation of oil in the vacuum system.

What is the purpose of the distributor valve in a deicing system utilizing deicer boots?. to equalize the air pressure to the left and right wings. to sequence the deicer boots inflations symetrically. to distribute anti-icing fluid to the deicer boots.

Where are the heat sensors located on most aircraft with electrically heated windshields?. imbbeded in the glass. atached to the glass. around the glass.

Two possible sources of heat for the operation of a wing thermal anti-icing system are. firts stage of the air cycle turbine and turbo compressor. compressor bleed air and aircraft electrical system. combustion heater and exhaust gases.

What maintains normal windshield temperature control in an electrically heated windshield system?. thermal overhead switches. thermistors. electronic amplifiers.

Arcing in an electrically heated windshield panel usually indicates a breakdown in the. temperature sensing elements. autotransformers. conductive coating.

Which of the following connects vacuum to the deicer boots when the system is not in operation, to hold the boots tightly against the leading edges in flight?. vacuum relief valve. ejector. distributor valve.

How do deicer boots help remove ice accumulations?. by preventing formation of ice. by breaking up ice formation. by allowing only a thon layer of ice to built up.

Why are the tubes in deicer boots alternately inflated?. alternate inflation of deicer boot tubes keeps disturbance of teh airflow at minimun. alternate inflation of deicer boot tubes does not disturb the airflow. alternate inflation of deicer boot tubes relieves the load on the air pump.

Carburetor icing may be eliminated by which of the following methods?. alcohol spray and heated induction air. ethylene glycol spray and heated induction air. electrically heated air intake, ethylene glycol spray or alcohol spray.

Why should a chemical rain repellant not be used on a dry windshield?. it will etch the glass. it will restrict visibility. it will cause glass crazing.

What is the principle characteristic of a windshield pneumatic rain removal system?. an air blast spreads a liquid rain repellant evenly over the windshield that prevent rain drops from clinging to the glass surface. an air blast forms a barrier that prevents raindrops from stricking the windshield surface. a pneumatic rain removal is simply a mechanical windshield wiper system that is pawered by pneumatic system pressure.

What mixture may be used as a deicing fluid to remove frost from an aircraft surface?. ethylene glycol and isopropyl alcohol. methyl ethyl ketone and ethylene glycol. naphta and isopropyl alcohol.

Which of the following is the best means to use when removing wet snow from an aircraft?. brush or a squeegee. hot air. warm water.

What are three methods of anti-icing aircraft windshields? 1. Blanket-type heating system. 2. An electric heating element in the windshield. 3. Heated air circulating system. 4. Hot water system. 2,3,5,. 1,2,6. 2,3,4.

What icing condition may occur when there is no visible moisture present?. injector ice. inlet ice. carburator ice.

What should be used to melt the ice in a turbine engine if the compressor is immobile because of ice?. deicing fluid. anti-icing fluid. hot air.

What is used as a temperature-sensing element in an electrically heated windshield?. thermocouple. thermistor. thermometer.

Heat for the cabin of a jet transport airplane is provided by ____________ air. compressor bleed. engine bledd.

In a jet transport airplane, hot compressor bleed air is mixed with cold air from the ________ machine to get air of the correct temperature for the cabin. air cycle. vapor cycle.

The first heat that is lost from the hot compressor bleed air in an air-cycle machine is removed by the___________ heat exchanger. primary. firts.

After the air leaves the primary heat exchanger it is heated as it is compressed by the __________ compressor. centrifugal. axial.

After leaving the air-cycle machine centrifugal compressor the air gives up some of its heat as it passes through the _____________ heat exchanger. secondary. primary.

More heat is removed from the pressuri zing air after it leaves the secondary heat exchanger as it spins the _____________ which drives the centrifugal compressor. expansion turbine. normal turbine.

The final stage of cooling is done when the air ________ upon leaving the turbine. expands. contracts.

Moisture that condenses from the pressurizing air after it leaves the expansion turbine is removed by the _________________ . water separator. water filter.

Water is prevented from freezing in the water separator by routing some _________ around the air-cycle machine to mix with cold air and raise its temperature. warm air. hot air.

In a vapor-cycle cooling system, heat from the cabin is absorbed into the refrigerant in the ________. evaporator. condensator.

Heat taken from the cabin is transferred into the outside air by the ________. condenser. evaporator.

The refrigerant enters the evaporator as a ______ -pressure _______. low, liquid. high,vapor.

The refrigerant leaves the evaporator as a ______ -pressure ______. low, vapor. liquid,high.

The refrigerant enters the condenser as a ______ -pressure ______. high,vapor. low, liquid.

The refrigerant leaves the condenser as a ______ -pressure _______. high, liquid. low, vapor.

The receiver-dryer holds the refrigerant in its _______ state. liquid. vapor.

The two units that divide an air conditioning system into a high side and a low side are the______________ and the _______ . thermostatic expansion, compressor. thermostatic expansion, condenser.

The component in an air conditioning system that increases both the temperature and the pressure of the gaseous refrigerant is the ___________. compressor. condenser.

Cycling of a compressor that is belt-driven from the aircraft engine is accomplished by using an electromagnetic _______ in the drive pulley. clutch. separator.

The condenser is in the ______ side of an air conditioning system. high. low.

The air conditioning system component that meters liquid refrigerant into the evaporator coils is the _______________. thermostatic expansion valve. thermostatic expansion switch.

The evaporator is in the ______ side of an air conditioning system. high. low.

The air leaving the evaporator of a properly functioning air conditioning system should have a temperature of between _____°F and _____ °F. 35, 45. 45, 55.

When using an electronic leak detector, the probe should be held ______ a location of a suspected leak. above. below.

Two types of ice control are: anti-icing and de-icing. cooling and heating.

The ice control system that prevents the formation of ice is the _______________ system. anti-ice. de ice.

The ice control system that removes ice after it has formed is the ____________ system. de-ice. anti-ice.

Frost on an aircraft wing ________ constitute a hazard to flight. does. does not.

A pitot head is anti-iced with a/an _________ heater. electric. hot air.

An operational check of a pitot-static tube heater may be made by watching the ______________ when the heater is turned on. AMMETER. VOLTMETER.

Frost may be removed from an aircraft by spraying it with a deicing fluid that normally contains __________ and ____________. ethylene glycol, isopropyl alcohol. isopropyl alcohol, ethyl ketone.

Electrically heated windshields that use a conductive film as the heating element are energized with ___. AC. DC.

The temperature of an electrically heated windshield is sensed by _________ -type sensors laminated between the glass panels. thermistor. thermocouples.

A breakdown of the electrically conductive film inside an electrically heated windshield can cause ____________ . arcing. burning.

Three methods of preventing ice from forming on a windshield and obstructing pilot visibility are: A. warm air blown between laminated glass panels B. chemical anti-ice fluid sprayed on the outside C. electrically heated windshields. A. warm air blown between laminated glass panels B. chemical anti-ice fluid sprayed on the outside C. electrically coold windshields.

The fluid that is used for anti-icing propeller blades is a mixture of _______________and _____________________ . isopropyl alcohol, ethylene glycol. isopropyl alcohol, methylene glycol.

Current for the heating elements in an electrothermal deicing system for a propeller is carried from the airframe into the propeller through ______________and __________________________. brushes, slip rings. brushes and rings.

Reciprocating-engine-powered airc raft get the air for inflating the deicer boots from alan _________________. vacuum pump. pneumatic pump.

Deicing systems are turned on _____________ icing is encountered. before. after.

Deicer boots are attached to modern aircraft leading edges with a/an ____________ . adhesive. stick.

Before installing a surface-bonded deicer boot to the leading edge of an aircraft wing, the paint must be _____________. cleaned. removed.

The oil that is used to lubricate a "wet" vacuum pump is removed from the discharge air by a/an _________________. oil filtering element. oil separator.

Deicer boots should be cleaned with ___________ . oil cleanner. soap and water.

Deicer boots are actuated symmetrically to minimize contro l problems caused by disturbance of the ____________. airflow. laminar wind.

The inflation sequence of a pneumatic deicer boot system is controlled by a ___________ /timer. temporizator. distrubutor valve.

The amount of sucti on used to hold the deicing boots deflated when the system is not operating is controlled by a/an _________________valve. suction relief. suction metering.

During normal operation of a pneumatic deicer system, the air pressure gage will _________. fluctuate. remain steady.

During normal operation of a pneumatic deicer system, the suction gage will __________. fluctuate. remain steady.

The component in a multi-engine pneumatic deicing system that directs suction into the boots when the system is not operating is the .___________________. distributor valve. distributor pump.

Two sources of heat for thermal ice control on reciprocating-engine-powered aircraft are: a. combustion heaters b. augmenter tubes around the exhaust. a. hot bleed air b. augmenter tubes around the exhaust.

The temperature of the air produced by a combustion heater is controlled by cycling the _______ on and off. fuel. ignition.

Carburetor ice ______ form when the outside air temperature is above 70°F. can. can not.

Visible moisture _______ required for the formation of carburetor ice. is. is not.

The heat for eliminating carburetor ice normally comes from the ____________ . exhaust system. heating system.

Fuel-injected engines have an alternate source of induction system air to use in the event the __________ ices over. air fills. air filter.

When carburetor heat is used, the intake air ________ filtered. is not. is.

A carburetor heater system for a sea-level engine should be able to increase the temperature of the air by ______ °F. 90. 70.

Tee is prevented from sticking to the throttle valve and venturi in a carburetor by spraying _______________ into the carburetor inlet. isopropyl alcohol. ethylene.

If the compressor of a turbine engine is immobile because of ice, the ice should be melted with ________ . warm air. chemical de-icer.

Type I FPD fluids are used primarily for _______. anti-icing. deicing.

Heated FPD fluids are most effective for _______. anti-icing. deicing.

For most effective anti-icing, the FPD fluid is applied _______ (or ). hot. cold.

Acrylic plastic windshields on small general aviation aircraft are treated to ease the removal of rain bycoating them with a smooth coat of ____ . wax. alcohol.

Three types of rain removal systems for large aircraft are: mechanical. chemical. pneumatic. electrical. automatically.

Chemical rain repellent _______________ be applied to a dry windshield. should. should not.

The air for a pneumatic rain removal system comes from the _____________. turbine engine compressor. turbine hot air compressor.