JET ENGINE SYSTEM FOR SEM -IV1.Vapor lock can become serious enough to

a. Block the fuel flow completely and stop the engine. b. Even small amounts of vapor in the inlet line restrict the flow to the engine-driven pump.c. Reduce its output pressure.d. All of the above.

2.Electronic engine controls have alloweda. Increases in controlling the metered fuel flow to the engine.b. Decreases in controlling the metered fuel flow to the engine. c. Constant in controlling the metered fuel flow to the engine. d. All of the above.

3.The purpose of 'squeeze film' type bearing is to.a. Increase the flow of oil to the rolling element.b. Minimize the effect of vibration.c. Improve outer race cooling.

4.In a jet engine the rotating assembly oil seals are maintained oil tight by means of.a. A garter seal.b. An annular expander ring.c. Air pressure.

5.Mark the correct statement about engine be a. The initial function of the bearing is to support main engine b. The number of bearing necessary for the particular engine the decided by the

length and weight of the engine rotor c. Number of bearing be decided that how many bearing can be installed d. All above are correct

6.Bearing use in turbojet engines are a. Always ball bearing b. Must be roller bearing c. Combination of ball and roller bearing d. As in © and also as per requirement of the engine

7.The after burning jet pipe is made of:a. Stainless steel b. Aluminum alloy c. Heat resisting nickel alloy d. Corrosion resistant iron

8.After burning system is:a. Mostly used in military a/c b. Used for immediate take off and climb c. Required extra consumption of fuel d. All above are correct

9.Water injection system:a. It's a thrust augmentation method b. Water provides additional thrust c. Water is added in the compressor d. As (a) + (b) + (c) are correct

10.Disadvantage of water system are:a. Water and water injection system are very heavy b. Erosion of compressor blades can occur c. As (a) + (b) are correctd. no disadvantage of water system in engine

11.Methanol is mixed with water: a. Provides an additional source of fuel

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b. Prevents freezing of water c. Methanol is not used with water d. As (a) + (b) are correct

12.The afterburner system:a. Is a thrust augmentations method b. Fuel is not used to operate this system c. Air is only used d. None of the above is correct

13.All engines that incorporate an afterburner must be equipped with:a. A variable area exhaust nozzle b. Need not have variable area propelling nozzle c. Fixed nozzle is only required d. None of the above is correct

14.At what stage in turbo jet engine is pressure greatest?a. Compressor inletb. Exhaust pipec. Turbine inletd. Compressor outlet

15.The Brayton cycle is known as the constant a. Pressure cycle. b. Temperature cycle. c. Mass cycle.

16.The basic groups of Gas turbine engine fuel controls can be a. Hydro-mechanical.b. As (a) or Hydromechanical/electronic.c. As (b) or Full Authority Digital Engine Control. d. As (c) or Full Authority Digital Electronics Control.

17.FADEC meansa. Full Authority Digital Electrical Control.b. Full Automatic Digital Electronics Control.c. Full Authority Digital Engine Control.d. Full Automatic Digital Electronics Control.

18.When the engine is accelerated, energy must be furnished to the turbine in excess of that necessary to maintain a a. Constant rpm.b. Constant pressure.c. Constant volume.d. Constant temperature.

19.The fuel system must bea. Supply fuel so that the engine can be easily started on the ground and in the air.b. Injected into the combustion chambers in a combustible condition during engine starting and

that combustion must be sustained while the engine is accelerating to its normal idling speed.

c. Respond occurs during a rapid acceleration.d. All of the above

20.MTCS (Regarding Afterburning (or reheat)a. Afterburning (or reheat) is not a method of augmenting the basic thrust of an engine to

improve the aircraft take-off, climb and (for military aircraft) combat performance.b. The increased power could not be obtained by the use of a larger engine, but as this would

increase the weight, frontal area and overall fuel consumption.c. Afterburning provides the best method of thrust augmentation for short periods.

21.If water only was injected, it would reduce the a. CPR.b. ITT

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c. TIT

22.Bearing seals isa. To prevent loss of oil into the gas path.b. To prevent loss of fuel into the gas path.c. Only (b) is correct.d. None of the above.

23.The general causes of vapor lock are a. The lowering of the pressure on the fuel.b. High fuel temperatures.c. Excessive fuel turbulence.d. All of the above.

24.The vapor pockets formed by this premature vaporization restrict the fuel flow through units which are designed to handle liquids rather than gases. The resulting partial or complete interruption of the fuel flow is called a. Vapor lock.b. Control lockc. Hydraulic lock.d. All of the above.

25.The fuel control can sense many different inputs such as a. Power lever position, engine rpm for each spool b. Compressor inlet pressure and temperaturec. Burner pressure, compressor discharge pressured. All of the above.

26.Fuel entering the fuel control unit first passes through a a. 10-micron filter.b. 30-micron filterc. 20-micron filterd. 50-micron filter

27.APU engine that uses the aircraft fuel system to supply fuel to the fuel control. An electric -------------may be used to supply fuel under pressure to the control.a. Main fuel pumpsb. Boost pump.c. Shutoff valved. None of the above.

28.Which type of valve maintains a constant pressure drop across the metering valve by bypassing fuel to the pump inlet so that metered flow is proportional to metering valve area?a. Differential pressure valveb. Relief valvec. Check valved. All of the above

29.EEC meansa. Engine Electronic control.b. Electronic engine controls.c. Electrical engine controls.d. Engine Electrical controls.

30.__________is the popular brand of hand servicing type of anti-icing and anti-micro-biocidal agenta. MISTb. PRISTc. FRISTd. None of the above

31.The inlet check valve in fuel nozzle opens ata. 5 to 10 psib. 10 to 15 psic. 5 to 15 psi

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d. None of the above

32.Labyrinth seal is used toa. Cold location.b. Hot location.c. Both (a) & (b) are correctd. None of the above.

33.Which type of seals is used for cold section in jet engine?a. Carbon seal.b. Labyrinth seal c. Ether (a) or (b) d. Both (a) & (b) are correct

34.Seals often used to sealing the main bearing areas in engine in hot section pressurized seal are used to prevent oil leakage.a. Carbon seal.b. Thread seal c. Double groove seal.d. Ring seal.

35.______ has individual flow dividera. Simplexb. Duplex-single linec. Duplex double lined. P & D valve

36.Full Authority Digital Engine Control system hasa. A self-monitoring, self-operating.b. A redundant & fail-safe setup. c. A comprises of a digital computer and the other accessories (that control all the aspects of

aircraft engine performance) d. All of the above.

37.Full Authority Digital Engine Control system hasa. A digital electronic control system able to autonomously control the engine b. Throughout its whole operating range in both normal and fault conditions.c. A self-monitoring, self-operating.d. All of the above.

38.What are the position of P & D valve when jet engine is shut downa. P valve open and D valve closedb. Both valves closedc. Both valves open d. P valve closed and D valve open

39.Which of the following factors helps determine the proper grade of oil to use in a particular enginea. Adequate lubrication in various attitudes of flight.b. Positive introduction of oil to the bearingsc. Operating speeds of bearingsd. None of the above

40.What will result if an oil filter becomes completely blocked?a. Oil will flow at a reduced rate through the system.b. Oil flow to the engine will stop.c. Oil will flow at the normal rate through the systemd. None of the above

41.As a general rule, a small amount of small fuzzy particles or gray metallic paste on a turbine engine magnetic chip detectora. Is considered to be the result of normal wear.

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b. Indicates an imminent component failurec. Indicates accelerated generalized weard. None of the above

42.The purpose of a de-aerator in a turbine engine oil tank is to providea. A collection point for sedimentsb. For a pressurized oil supply to the oil pump inlet.c. Separation of entrained air from scavenged oil.d. Both (a) and (b) are correct

43.The pumping capacity of the scavenger pump in a dry sump aircraft engine's lubrication systema. Is greater than the capacity of the oil supply pump.b. Is less than the capacity of the oil supply pumpc. Is usually equal to the capacity of the oil supply pump in order to maintain constant oiling

conditionsd. Both (b) and (c) are correct

44.Oil picks up the most heat from which of the following turbine engine components?a. Rotor coupling.b. Compressor bearing.c. Turbine bearingd. Both (a) and (b) are correct

45.What prevents pressure within the lubricating oil tank from rising above or falling below ambient pressure?a. Oil tank check valve.b. Oil pressure relief valve.c. Oil tank vent.d. Both (a) and (b) are correct

46. What is the purpose of the last chance oil filters?a. To prevent damage to the oil spray nozzle.b. To filter the oil immediately before it enters the main bearings.c. To assure a clean supply of oil to the lubrication system.d. Both (b) and (c) are correct

47.In a turbine engine oil system, the temperature bulb senses oil temperaturea. At a point after the oil has passed through the oil cooler.b. While the oil is in the hottest area of the engine.c. Immediately before the oil enters the oil cooler.d. Both (a) and (b) are correct

48. The oil dampened main bearing utilized in some turbine engines is used toa. Provide lubrication of bearings from the beginning of starting rotation until normal oil

pressure is established.b. Provide an oil film between the outer race and the bearing housing in order to

reduce vibrationc. Tendencies in the rotor system, and to allow for slight misalignment. Dampen surges in oil

pressure to the bearingsd. Both (a) and (c) are correct

49.In water injection liquid is vaporized it causes a. Decreases density and man airflow in compressor b. Increases density and man airflow is compressorc. Water injection has no effect in engined. None above is correct

50.Water injection system:a. It is a thrust augmentation methodb. Water provides additional thrustc. Water is added in the compressor d. All of the above are correct

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51.Possible failure related ferrous metal particles in turbine engine oil cause an (electrical) indicating type magnetic chip detector to indicate their presence bya. Disturbing the magnetic lines of flux around the detector tip.b. Bridging the gap between the detector center (positive) electrode and the ground

electrode.c. Generating a small electric current that is caused by the particles being in contact with the

dissimilar metal of the detector tip.d. Both (a) and (c) are correct

52.What is the primary purpose of the oil to fuel heat exchanger?a. Cool the fuel.b. Cool the oil.c. De-aerate the oil. d. Both (a) and (c) are correct

53.The type of oil pumps most commonly used on turbine engines are classified asa. Positive displacement.b. Variable displacement.c. Constant speed.d. Both (b) and (c) are correct

54.What is FCOC also known as?a. ACOCb. FOHEc. FHOEd. Both (a) and (c) are correct

55.What is the most desired property of lubricating oil?a. High flash pointb. High densityc. High volatilityd. Both (b) and (c) are correct

56.In FCOCa. Oil cools the fuelb. Fuel cools the oilc. Both (A) and (B) are correctd. None of the above

57.The thermostatic valve is made ofa. Iron and brassb. Iron and nickel c. Brass and steeld. Both (b) and (c) are correct

58.Dual discharge orifice is in a. Simplexb. Duplex-single linec. Duplex double lined. Both (b) & (c) are correct

59.________is a mechanical device located at low point of combustion case.a. Temperature datum valveb. FADECc. Combustor drain valved. None of the above

60.MTCSa. The thermostatic valve opens when oil is cold and closes when the oil is hotb. The thermostatic valve closes when oil is cold and open when the oil is hotc. Only (b) is correctd. None of the above

61.Magnetic chip detectors are installed mostly ina. Pressure line

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b. Scavenge linesc. All return linesd. Both (a) and (c) are correct

62.What is the primary purpose of oil breather pressurization system that is used on turbine engine?a. Provide proper oil spray pattern from oil jetsb. Prevent foamingc. Allow de-aeration of oild. Both (b) and (c) are correct

63.Which lubricating system is controlled by limiting the pressure in the feed line to a given design valuea. Full flow typeb. Pressure relief valve c. Dry sump d. Both (a) and (c) are correct

64.Power turbine & compressor turbine area. Interconnected to each otherb. Has different rpm c. Has same rpm d. None of the above

65.The function of the nozzle diaphragm in a turbine engine is to – a. Decrease the velocity of exhaust gases b. Center the fuel spray in the combustion chamber c. Swirl and collect and exhaust gases into a single exhaust jet d. Direct the flow of gases to strike the turbine blades at a desired angle

66.The purpose of a relief valve installed in the tank venting system of a turbine engine oil tank is toa. Prevent oil pump cavitations by maintaining a constant pressure on the oil pump inlet.b. Maintain internal tank air pressure at the ambient atmospheric level regardless of

altitude or rate of change in altitudec. Maintain a positive internal pressure in the oil tank after shutdown to prevent oil pump

cavitations on engine start.d. Both (a) and (c) are correct

67.The main characteristics of engine oil area. Viscosityb. As (a) and Pour pointc. As (b) and Flash pointd. As (c) and Pressure resistance

68.In FCOC, which pressure has to be morea. Oil b. Fuelc. Fluidd. Both (b) and (c) are correct

69.When reheat is selected and in operation, the mass gas flow.a. Decreases.b. Remains the same.c. Increases.

70.Water at the inlet of the diffuser decreases the _______a. Temperature and pressure drop at turbineb. Temperature drop at the compressorc. Temperature and pressure drop at the combustion camber

71.When there is a reduction in atmospheric pressure due to increasing altitude or temperature will therefore cause a reduction in_____________.a. Thrust or BHP

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b. SHP or BHP.c. Thrust or SHPd. None of the above.

72.Engine power ratings during the period water injection is used are called _______ ratings as opposed to ______ ratings when water injection is off.a. Wet thrust; dry thrustb. Dry thrust ; wet thrustc. Only (b) is correct

73.The alcohol adds to the power by providing an additional source of fuel, but because the alcohol has ___________.a. Low power efficiencyb. High power efficiencyc. Low combustion efficiencyd. High power efficiency.

74.MTCSa. Water at inlet of compressor increase airflowb. Water at inlet of compressor decrease airflowc. Water at inlet of compressor constant airflow

75.When water is added at the front of the compressor power augmentation is obtained principally by the vaporizing liquid cooling the air, thus___________.a. Increase density and mass airflow.b. Decrease density and increase mass air flowc. Increase density and decrease mass air flow d. Both (b) and (c) are correct.

76.MTCSa. Water at inlet of the diffuser increase mass airflow through turbineb. Water at inlet of the diffuser constant mass airflow through turbinec. Water at inlet of the diffuser decrease mass airflow through turbine.d. Both (b) and (c) are correct.

77.When water injection is used, fuel flow is not reduced and is often increased. The increased thrust results from the a. Increase in Wa and/or Wfb. Decrease in Wac. Increase in Wfd. Decrease in Wa and/or Wf.

78.Dematerialized water is generally used to prevent deposit buildup on compressor blades that will lead to deterioration of thrust and more frequent ______ of the compressor and engine trimming.a. Increase airflowb. Field cleaning.c. Both (a) and (b) are correct.d. All of the above.

79.Power can be restored or even boosted as much as __________ % for takeoff by the use of water or water alcohol injection.a. 10 to 40b. 10 to 30c. 10 to 50d. 50 to 70

80.Water at the inlet of the compressor has______a. High turbine temperatureb. Low pressure turbinec. Low turbine temperature

81.Generally water/air ratios are in the order of_______ water to _____.a. 1 to 5 lb to 100lbb. 1 to 5lb to 50lbc. 1 to 5lb to 35lbd. 1 to 10lb to 45lb

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82.The reduction in turbine temperature when water alone is used allows the fuel system to schedule a _____, providing additional thrust.a. Increased fuel flowb. Decreased in fuel flowc. Both (a) and (b) are correct.d. None of the above.

83.MTCS (Regarding Spherical Roller Bearings)a. A roller bearing that has a barrel shaped roller.b. As (a) and Medium friction, medium to heavy loads and misalignment capabilities.c. As (b) and generally used for very high load applications with misaligned shafts to

housings.d. None of the above

84.What are the principal advantage of the duplex fuel nozzle used in many GTE-?a. Restrict the amount of fuel flow to a level where more efficient and completed burning of

fuel achievedb. Provide better atomization and uniform flow patternc. Allow wide range of fuel and filter to be usedd. All of the above

85.The type of oil pump most commonly used on turbine engine-a. Positive displacement pumpb. Variable displacementc. Constant displacementd. None of the above

86.Which seal provide specific amount of leakage-a. Carbon sealb. Labyrinth sealc. Elastomeric seald. All of the above

87.on twin shaft engine compressor bearing used-a. Ball bearing.b. Roller bearing.c. Both (a) and (b) are correct.

88.Main bearing oil seals used with turbine engines are usually what type(s)?.a. Teflon and synthetic rubber.b. Labyrinth and/or carbon rubbing.c. Labyrinth and/or silicone rubber.

89.If, during inspection at engine overhaul, ball or roller bearings are found to have magnetism but otherwise have no defects, they.a. Are in an acceptable service condition.b. Cannot be used again.c. Must be degaussed before use.

90.A carbon seal has which type of sealing arrangement?a. Full contact with race.b. Full contact with casing.c. Full contact with labyrinth.

91.The highest turbine bearing temperature takes place.a. All the time.b. At shut-down.c. At start-up.

92.MTCSa. Water at the inlet of the diffuser decrease the mass airflowb. Water at the inlet of the diffuser increase the mass airflowc. Both (a) and (b) are correct.d. None of the above

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93.Compressor injection increases mass airflow & also cools the combustion air/fuel mixture ,allowing increase in________a. Mass of air flowb. Fuel flowc. Temperatured. All of the above.

94.Water cools the combustion gases which allows additional fuel to be used without exceeding maximum temperature limits during takeoff increases in these engine parameters results in a thrust increase in the range of_____a. 10 % to 25%b. 10 % to 20%c. 10 % to 40%d. 10 % to 15 %

95.________valve is in corporate in the low point of fuel manifolda. Dump valveb. Pressurizing valvec. Temperature datum valved. None of the above

96.Inputs to the FADEC is given from:a. Flap/slat position and wt. On wheels statusb. N1 and N2 rpmc. Compressor exit temperature & exhaust gas temperatured. Both (b) and (c) are correct.

97.Where should the main fuel strainer be located in the aircraft fuel system? a. Downstream from the wobble pump check valve. b. At the lowest point in the fuel system. c. At any point in the system lowers than the carburetor strainer.d. All of the above

98.Fuel cross-feed systems are used in aircraft to a. Purge the fuel tanks. b. Jettison fuel in an emergency. c. Maintain aircraft stability.d. All of the above

99.Which of the following turbine fuel filters has the greatest filtering action of any present-day filter type? a. Micron filter. b. Plain screen mesh filter.c. Wafer screen filter.d. None of the above

100.Inlet water injection is designed for use at ambient temperature ___________.a. Above 30 o Fb. Above 40 o Fc. Below 30 o F d. Below 40 o F

101.Methyl / ethyl mixtures will generally be a blend _______% alcohol in either determined or distilled water.a. 35 to 50b. 30 to 60c. 35 to 45d. 45 to 80

102.Pure water is also widely used because it produces a greater cooling effect than a mixture of water and__________.a. Methyl and ethylb. Methyl or ethylc. Methyl and propaned. Methyl and ethane

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103.Carbon seals is blend of a. Carbon and graphite.b. Carbon and aluminum.c. Carbon and magnesium.d. Carbon and silicon.

104.Which type of bearing(s) provides a bearing surface for forces acting along axis to the shaft?a. Thrust bearingb. Journal bearingc. Linear bearingd. None of the above

105.Indentations on bearing races caused by high static loads are known as.a. Fretting.b. Galling.c. Brinelling.

106.The function of a labyrinth seal is to create.a. A restricted leakage of air between fixed and rotating components.b. An airtight seal between fixed and rotation components.c. An airtight seal between fixed adjacent casing surfaces.

107.The bearings of a compressor rotor are usually.a. Ball and roller.b. Plain.c. Sintered.

108.Bearing seal failure would most probably cause.a. High oil temperature.b. High oil consumption.c. Low oil pressure.

109.Why are oil seals pressurized?a. To ensure minimum oil loss.b. To ensure oil is forced into the bearings.c. To ensure that the oil is prevented from leaving the bearing housing.

110.What bearing is used to take axial loads on a main rotation shaft of a gas turbine engine?a. Plain bearing.b. Roller bearing.c. Ball bearing.

111.Seals on a gas turbine engine restrict leakage of oil by.a. Spring pressure.b. Closely tolerated contacting components.c. Air pressure.

112.An abradable lining in the fan case.a. Prevents fan blade tip rub.b. Produces less leakage at tips for anti-ice.c. Provides acoustic medium.

113.Squeeze film bearings are usually found on.a. H.P compressor section.b. The turbine section.c. LP compressor section.

114.Taper roller bearings accept loads in which direction.a. Axial loads only.b. Radial and axial in both directions.c. Radial and axial in one direction only.

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115.Some labyrinth seals.a. Control the outflow of air at the turbine.b. Are self-lubricating.c. Are spring loaded

116.__________thrust is usually high enough without water injection for almost any aircraft without gross takeoff weight.a. At low ambient temperatureb. At high ambient temperaturec. At constant temperature.d. Both (b) and (c) are correct.

117.Which of the following is the most advantageous method of thrust augmentation a. Water injectionb. After burningc. Ducted fan and by-passd. Both (a) & (b) are correct

118.De-mineralized is generally used for water injection - a. To prevent deposit build upb. To prevent frequent field cleaningc. To prevent frequent engine trimmingd. All the above

119.In method of thrust augmentation “wet- thrust” a. Is called when water injection not usedb. “Wet thrust” when water injection is usedc. Fuel is added in wet thrust d. None is correct

120.The maximum power output of a gas turbine engine depends to a large extent upon the a. Densityb. Mass of the airflow passing through the engine.c. Ether (a) or (b) are correctd. None of the above

121.MTCS (regarding water injection system)a. The maximum power output of a gas turbine engine depends to a large extent upon the

density or weight of the airflow passing through the engine.b. A reduction in thrust or shaft horsepower as the atmospheric pressure decreases with

altitude, and/or the ambient air temperature increases.c. The power output can be restored or, in some instances, boosted for take-off by cooling the

airflow with water or water/methanol mixture (coolant).d. All of the above.

122.As a result of high ambient temperature the special rating engine may suffer a thrust loss which can be restored by: a. Means of the water injections into the combustion chamberb. Power cannot be restored in these enginesc. EGT can go to any circuitd. All above are wrong answers

123.MTCS (regarding water injection system)a. When water/methanol mixture is sprayed into the compressor inlet, the temperature of the

compressor inlet air is reduced and consequently the air density and thrust are increased.b. The injection of coolant into the combustion chamber inlet increases the mass flow through

the turbine, relative to that through the compressor.

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c. When the injection system is switched on, water/methanol mixture is pumped from an aircraft mounted tank to a control unit.

d. All of the above.

124.Methanol is mixed with water: a. Provides an additional source of fuelb. Prevents freezing of waterc. Methanol is not used with water d. Both (a) and (b) are correct.

125.Screech liners in the afterburning jet pipe.a. Prevent unstable combustion.b. Prevent cyclic vibrations of large amplitude.c. Acts as noise suppressors.

126.Water methanol for cooling is injected into the.a. Compressor inlet or outlet.b. Engine hot zone.c. Combustion chamber.

127.On an injection system.a. Methanol is injected neat.b. Town water/methanol is injected.c. Demineralized water/methanol is injected.

128.When using water methanol in an axial flow compressor, it is injected into the.a. Compressor inlet or burner section.b. Burner.c. Intake.

129.The main reason for adding methanol to the water is to.a. Temper the cooling effect of the water to prevent distortion.b. Supply the additional heat required.c. Prevent mixture freezing.

130.The primary purpose of water injection is to.a. Decrease mass airflow.b. Increase the calorific value of the fuel.c. Cool the turbine.

131.Water used in a thrust augmentation system should be demineralised to prevent.a. Blocking the jet.b. Carbon formation.c. Fouling the blades and vanes.

132.The quantity of water usually carried by an aircraft equipped with water injection is enough for.a. Three take-offs.b. One take-off.c. Two take-offs.

133.Water methanol injection will increase thrust by up to.a. 70%.b. 50%.c. 30%.

134.Injection of water/methanol into compressor inlet causes.a. Increase in power due to the burning of methanol alone.b. Increase in power without the need for burning extra fuel.c. Increased efficiency of the engine due to reduced icing in the airflow.

135.Reheat is the term used to describe.a. Adding fuel in the exhaust section.b. Adding of fuel in the turbine section.

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c. Adding of fuel in the compressor section.

136.Water/methanol is injected.a. At high temperatures.b. At high temperature, at high altitudes.c. At high temperatures or high altitudes.

137.The reheat ignition system which incorporates a platinum/rhodium element is known as.a. Catalytic ignition.b. Hot-shot ignition system.c. Spark ignition system.

138.Water or water/methanol injected into the combustion chamber inlet increases.a. Mass airflow through the turbine.b. Combustion chamber outlet temperatures.c. Fuel to air ratio by up to 20%.

139.Methanol is added to water when augmenting thrust in order to.a. Reclaim lost pressure at the compressor.b. Increase the density of air entering the compressor.c. Reclaim lost heat at the turbines.

140.Afterburning is initiated in order to.a. Heat the exhaust to prevent choking at subsonic gas velocities.b. Burn off the fuel that is not combusted in the combustion section.c. Increase the local speed of sound at the jet nozzle.

141.How is the flame stabilised in the reheat system of a gas turbine engine?a. By creating a greater potential between inlet & jet pipe temperatures.b. By ensuring that the gas velocity is greater than the flame velocity.c. By ensuring that the flame velocity is greater than the gas velocity.

142.During operation of the engine equipped with water injection system, the metering of the coolant to the system is.a. Selected by the pilot.b. Due to atmospheric pressure.c. Due to altitude change.

143.Water methanol injection is used.a. At high altitude take off conditions only.b. At a combination of higher than normal air temperatures and high altitude take off

conditions.c. At higher than normal ambient air temperatures only.

144.The maximum power output of a gas turbine engine depends to a. A large extent upon the density.b. Weight of the airflow passing through the engine.c. Either (a) or (b) are correct.

145.When reheat is used, E.P.R.a. Is reduced.b. Remains constant.c. Is increased.

146.When water/methanol mixture is sprayed into the compressor inlet, the temperature of the compressor inlet air is --------------and consequently the air density and thrust are ------------a. Decrease and Decrease.b. Decrease and Increases.c. Increases and Decrease.

SUBJECTIVE QUESTION (Attempt any three question, each question have 10 marks)

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1. Write the FADEC affects of the engine.

2. Write the short notes on a. FCOC.b. Water Injection system.c. Fuel pump.d. Bearing.e. Fuel filter.

3. Write the input signal of FADEC.

4. Draw the fuel system and write the name of component.

5. Draw the twin spool turbofan engine and show the gearbox.

6. Briefly Explain Labyrinth and carbon seals.

7. Write the output signal of FADEC.

8. Draw the lubrication system and write the name of component.

9. Draw the turboprop engine and show the gearbox.

10.Write the short notes on a. Seals.b. FCUc. MCDd. Afterburner system.e. Fuel filter.

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