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AME LICENCE EXAM OCT’11

“JET ENGINE”

1. The fan rotational speed of a dual axial compressor forward fan engine is some asa. Low pressure compressorb. Forward turbine wheelc. High pressure compressor

2. In a gas turbine engine combustion occurs at constanta. Volumeb. Pressurec. Density

3. Highest gas pressure in turbojet engine is a. At outlet of tailpipe sectionb. At entrance of turbine sectionc. At entrance of burner section

4. In dual axial flow or twin spool compressor system first stage turbine drives the a. N1 and N2 compressorb. N2 compressorc. N1 compressor

5. Free turbine a. Is independent of gas generator turbine and attached to compressor shaftb. Attached to gas generator turbine and independent of compressor shaftc. Attached to gas generator turbine and compressor shaftd. Independent of both gas generator turbine and compressor shaft.

6. An exhaust cone placed aft of the turbine in a jet engine will cause the pressure in the first part of exhaust duct to

a. Increase and velocity to decrease b. Increase and velocity to increase c. Decrease and velocity to increase

7. Which statement is true regarding a/c engine propulsion?a. An engine driven propeller impart a relatively small amount of acceleration to large

mass of airb. Turbojet and turbofan engine impart a relatively large amount of acceleration to small

mass of airc. In modern turbofan engine, nearly 50% of the exhaust gas energy is extracted by

turbine to drive the propeller and compressor with the rest providing exhaust thrust

d. Both A and B

8. Where do stress rupture cracks usually appear on turbine bladesa. Access the blade root, parallel to fir treeb. Along the leading edge, parallel to the edgec. Across the leading or trailing edge at a right angle to the edge length

9. Which turbine engine compressor offers the greatest advantage for both starting flexibility and improved high altitude performance

a. Dual stage, centrifugal flow b. Split spool, axial flow c. Single spool, axial flow

10. In a turbine engine with dual spool compressor, the low speed compressora. Always turn at the same speed as the high speed compressorb. Is connected directly to high speed compressorc. Seeks its own best operating speed

11. What is the proper starting sequencea. Ignition, starter, fuel b. Starter, ignition, fuelc. Starter, fuel, ignition

12. What should be done initially if a turbine engine catches fire when startinga. Turn off fuel and continuous cranking with starterb. Continuous engine start rotation and discharge a fire extinguisher into intakec. Continuous starting attempt in order to blow out the fire

13. Swirl type fuel nozzle providea. Provide rapid burning b. Handle large quantity of fuelc. Handle large quantity of aird. All the above

14. What type igniter plug is used in the low tension ignition system of an aircraft turbofan enginea. Low voltage, high amperage glow plugb. Self ionizing or shunted gap type plugc. Recessed surface gap plug

15. Which of the following can cause fan blade shingling in a turbofan enginei. Engine over speed

ii. Engine over temperature iii. Large, rapid throttle movementsiv. FOD

a. 1,2b. 1,2,3,4c. 1,4

16. Which of the following is used to monitor the mechanical integrity of the turbines as well as to check the engine operating condition of turbine engine.

a. Engine oil pressure b. Exhaust gas temperature c. Engine pressure ratio

17. Which of the following fire detection system uses heat in the normal testing of the systema. Thermocouple and Lindberg systemb. Kiddee and Fenwal system c. Thermocouple and Fenewal system

18. What is the purpose of last chance oil filtera. To prevent damage to the oil spray nozzle b. To filter the oil immediately before it enter the main bearing c. To assure a clean supply of oil to the lubrication system

19. The purpose of relief valve installed in the tank venting system of a turbine engine oil tank is to

a. 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 altitude

c. Maintain positive internal pressure in oil tank after shutdown to prevent oil pump cavitations on the engine

20. Why do turbine engine ignition system require high energy a. To ignite the fuel under condition of high altitude and high temperatureb. Because the applied voltage is much greaterc. To ignite fuel under condition of high altitude and low temperature

21. The active clearance control (ACC) portion of an ECC aids turbine engine efficiency by a. Adjusting stator vane position according to operating condition and power requirement b. Ensuring turbine blade to engine case clearance are kept to minimum by

controlling case temperature c. Automatically adjusting engine speed to maintain a desired temperature

22. During test, metal chip detector particles placed in nitric acid, gives bright green color the particle is

a. CU or Bronzeb. Tinc. Aluminumd. Magnesium

23. Mark the incorrect statement a. Propeller brake use to stop wind milling of feathered propeller and reduce time for

propeller to come rest after engine shut down

b. NTS system designed to prevent excessive propeller dragc. TSS device which will provide manual feathering when armed during take offd. Safety coupling is a safety device baking up the NTS system

24. Before shutdown of the engine it is essential to run the engine at ideal for few minutes, this is mainly to

a. Avoid fire hazard b. Stabilize all parameterc. As in (b) and measure parameters d. Avoid thermal stresses

25. The pitch movement of the propeller blade controlled a hydraulic servo piston, the increase of oil pressure in the servo makes the propeller blade angle to

a. Low pitch positionb. High pitch propeller c. Run a low RPMd. High pitch with high RPM

26. Turbofan engine uses TGT, N2 signal as a feedback to regulate the fuel flow through amplifier for which type of type of N2 sensor used is

a. Tacho – generatorb. Synchro type c. Capacitance typed. Variable reluctance used probe

27. When pt2 probe is blocked due to ice formation then EPR gauge will a. Over read b. Under read c. Read zero d. Read maximum on dial

28. Engine flame out leana. Is due to high fuel pressure, at low engine speed, in high altitude flightb. Is due to low fuel pressure, at low engine speed in high altitude flightc. Is due to low fuel pressure at high engine speed in high altitude flight

29. Hot spot on a tale cone of a turbine engine are possible indication of malfunction fuel nozzle or a. Faulty combustion chamber b. Faulty igniter plug c. Improperly positioned tail cone

30. What must be after the fuel control unit has been replaced on a turbine enginea. Re trim the engineb. Recalibrated the fuel nozzle c. Fuel flow check d. Both A and B

31. Which of the following is the turbine ultimate limiting factor of turbine engine operationa. Compressor inlet temperature b. Turbine inlet temperature c. Burner can pressure

32. After major overhaul, jet engine was tested in the test cell which of the following test is done at the beginning and end of the test

a. Vibration surveyb. Hot air leak test c. Engine power settingd. Compressor work line

33. Mark the correct statement in respect of starter generator a. Starter generator has two separate armature b. Starter generator has two field winding series field winding is used for high

starting torque and shunt field winding for generator c. Starter generator has three connection ( A + shunt field connection, B + armature

connection, c + series field connection)d. All the above

34. Compressor damage may cause a. Engine vibrates at high RPMb. Engine rpm hung up during startingc. High oil pressure d. Both A and B

35. When the airplane is in rest the thrust produce isa. Gross thrust b. Net thrustc. Ram dragd. Total thrust

36. The efficiency which is prime factor in gas turbine engine isa. Propulsive efficiency b. Thermal efficiency c. Volumetric efficiency d. All the above

37. Curling in turbine blade tipa. Not allowed b. Allowed c. Allowed provided no sharp bend on tipd. Not allowed provided no sharp bend on tip

38. Alpha range of the propeller a/c operation a. Is the non governing range from reverse position to the “flight ideal” position b. Is the governing range or flight range from “flight idle” to “take off” position

c. Is the governing range from “take off” to “flight ideal” positiond. Is the non governing range “flight ideal” to “take off” position

39. Engine has high rpm, EGT and fuel flow when set to expected ERP, the probable cause is a. EPR indicator faultyb. EGT out of adjustmentc. Fuel control may be defective

40. To operate VSV and IGV the hydraulic pressure requirement is fuel by a. Hydraulic system b. Pneumatic systemc. Fuel system

41. Variable reluctance speed probe is used to measurea. EPRb. RPMc. EGTd. Vibration

42. In axial flow compressor to maintain constant velocitya. Reduce annulus area gradually from front to rearb. Rotor & stator are arranged axially and maintaining constant velocity to rearc. Length of blade increase towards rear for maintain velocity constant

43. Thrust at inlet duct is a. Directly proportional to stagnation density b. Indirectly proportional to stagnation densityc. Not proportional to stagnation density

44. Maximum energy loss in case of turbopropa. Propeller lossb. Turbine lossc. Compressor lossd. None

45. Master chip detector is positioned a. Combined scavenge line, downstream of scavenge filterb. Combined scavenge line, upstream of scavenge filterc. Combined pressure line, downstream of pressure filterd. Combined pressure line, upstream of pressure filter

46. Major parts for cooling requirementa. HP/IP structureb. Rotor structure c. Bearing support structure

47. The point where friction loss is equal to ambient is known as

a. Ram recovery point b. Ram loss pointc. Duct efficiency ratiod. Total recovery point at compressor inlet

48. Propulsive efficiency isa. Work wasted by exhaust / work completed b. Work completed / work wasted by exhaust c. Work wasted + work completed / work completed d. Work completed / work wasted + work completed

49. Propulsive efficiency is maximum when a. Aircraft speed is equal to exhaust velocityb. Aircraft speed is equal to inlet velocityc. Aircraft speed is more than exhaust velocity d. Exhaust velocity is more than aircraft speed

50. The igniter plug which is slightly protrude inside combustion chamber for efficient spark is a. Constrained gap typeb. Annular typec. Self ionizing type

51. Mark the correct statementVibration EGT FF Speed

a. Voltage current frequency DC pulseb. Current emf DC pulse frequencyc. Current DC pulse emf currentd. Current emf current DC pulse

52. During inspection turbine engine component exposed to high temperature may only be marked with such material as allowed by manufacture. These materials generally include

i. Layout dye ii. Commercial felt tip marker iii Wax or grease pencil iv. Chalk

v Graphite lead pencil a. 1,2 & 4b. 1,3 & 4c. 2,4 & 5d. 1,3 & 5

53. Which of the following are include in a typical turbine engine ignition systemi. Two igniter plug

ii. Two transformeriii. Two low tension igniter lead iv. One exciterv. Two high tension igniter lead

a. 1,2 & 3b. 1,2 & 4

c. 1,2 & 5d. 2,3 & 5

54. How is aircraft electrical power for propeller deicer system transferred from the engine to the propeller hub assembly

a. By slip rings and segment platesb. By slip rings and brushesc. By flexible electrical connectors

55. The primary purpose of a cuff on a propeller is to a. Distribute anti-icing fluid b. Strength the propeller c. Increase the flow of cooling air to the engine nacelle

56. Propeller blade tracking is the process of determining a. Plane of rotation of the propeller with respect to aircraft longitudinal axisb. That the blade angle are within the specified tolerance of each other c. The position of the tips of the propeller blade relative to each other

57. Anti siphoning in oil system is achieved bya. Vent in oil tank b. Highest pressure in the line vented to the oil tankc. NRV in flow line

58. Which is the non-design factor which affect the thrust\a. Weight of fuel flowb. Turbine inlet temperature c. Speed of the aircraft d. Size of nozzle area

59. Variable guide vane operating characteristic depends ona. CIP and engine speed b. CIT and engine speedc. CIT & CIPd. CIT, CIP &CDP

60. Turbine engine based ona. Boyle’s lawb. Charles law c. Otto cycle

61. Turbofan engine flat rated to sea level standard day plus 16oCthena. Increase in temperature beyond 32oC thrust decrease b. Increase in temperature beyond 31oC thrust decreases c. Increase in temperature beyond 32oC thrust increases d. Increases in temperature beyond 31oC thrust increases

62. Sulphur in fuel is kept to minimum asa. It is difficult to remove completely b. It is compound cause corrosion c. It mix with water to form sulphuric acid and with oxygen forms sulphuric dioxided. All the above

63. A continuous loop fire detector is what type of detectora. Spot detector b. Overheat detector c. Rate of temperature rise detector

64. There are two type of thrust reverse of thrust reverse a. Clamshell and bucket typeb. Cascade and bucket typec. Aerodynamic blockage and mechanical blockage

65. Which term is used to describe a permanent and cumulative deformation of the turbine blade of a turbojet engine

a. Stretchb. Distortionc. Creepd. Crack

66. During trimming excessive wind in tailpipe direction can causea. False high EPRb. As in (a) cause low trim c. False low EPRd. As in (c) cause high trim

67. An engine trim curve is used for trimming an engine in the fluida. Up trim an engine to compensate for inlet duct loss and air bleed lossb. To compensate for any thrust deterioration which might result from accumulate

deposited of dirt or scale on the compressor bladec. Both (a) and (b) d. Down trim engine to bring EGT within limits

68. Mark the correct statementa. Combustion flame out occurs at high air velocityb. Lean die out occurs due to slow air velocity at low altitudec. Slow air velocity cause flame out at high altitude and as in (a)d. All the above

69. Features of “controlled diffusion airfoil” in gas turbine enginea. Sharp leading edge and trailing edge b. Used only in compressorc. Permit higher mach number without loss in efficiency d. All the above

70. EPR indicator is a direct indication of a. Engine thrust being produced b. Pressure ration between the front and aft end of compressorc. Ratio of engine rpm to compressor pressure

71. A fuel or oil fire is defined asa. Class A fire b. Class B fire c. Class C fired. Class D fire

72. Some turbojet engine is equipped with two spool or split spool compressor. When there engine are operated at high altitude

a. Low pressure rotor will increase in speed as the compressor load decreases in the lower density air

b. Low pressure compressor seeks its own best operating speedc. Throttle must be related to prevent over speeding of the high pressure rotor due to

lower density aird. Both (A) and (B) are correct

73. A turboprop engine produces 250lb of jet thrust with rating of 100SHP and 0.6 ESHP, then fuel flow is

a. 750b. 600c. 660d. 860

74. Bearing load can control bya. Oil dampened film b. Using bearingc. Position the sealing element around the compressor and turbine

75. Starting sequence of gas turbine engine i. APU power

ii. Power lever idle position iii. Connect electrical poweriv. Switch on fuel pumpv. Start switch on

a. 1,2,3,4,5b. 1,3,4,2,5c. 3,1,2,4,5

76. How is the fire extinguisher agent distributed in the engine sectiona. By spray nozzle & fluid b. By nitrogen pressure & slinger ringsc. By spray nozzle & perforated turbine

77. Over speeding of engine is controlled bya. Dedicated over speed protectionb. Switch from cockpit c. From PRSOV

78. In FCOC a. Fuel pressure is higher than oil pressure b. Oil pressure is kept high to avoid mixing of fuel into oil c. Both of them are at equal pressure

79. Typical accessories for gas turbine engine area. Oil pump, fuel pump, alternatorb. Oil pump, fuel pump, alternator, breather, starterc. Alternator, invertors, FCU, starter d. Motor, generator, oil pump, FCU

80. Rotators a. Hand cranking of the engine during testing

81. PRSOV a. Often known as HPSOV (high pressure shut off valve) located downstream of the

fuel metering valve to maintain a minimum HP pressure rise at low flow

82. Oil temperature gauge is installeda. Oil inlet lineb. Oil outlet line c. Oil cooler

83. Advantage of turbine engine over piston enginea. In jet engine the whole amount of air consume is used for combustionb. Piston engine is more expensive than jet engine c. Jet engine power produced is continuous instead of intermittentd. All the above

84. Internal air system is used fora. Cooling, scaling and controlling bearing load

85. Snubbers in fan bladesa. For damping the vibration b. Support the blade against bearing forcec. All the above

86. Accessory gearbox is housed near IP stagea. To reduce the length of beveled gear shaft

87. Cooling is required for

a. HP turbine, NGV, sealb. HP compressor, HP turbinec. LP turbine, NGV, LP compressor

88. The function of breather sub system is to a. Remove air from the bearing compartment b. Separate the breather air from the oilc. Vent the air overboardd. All the above

89. One function of nozzle diaphragm in turbine engine is to a. Decease the velocity of exhaust gasb. Center the fuel spray in combustion chamberc. Direct the flow of gases to strike the turbine blades at the desired angle

90. APU shutdown automatically a. Low oil pressure b. Over speed c. High oil temperatured. All the above

91. Hot streaking in turbine engine is due to a. Partially clogged fuel nozzle b. Misalignment combustion linerc. Uneven burner can coolingd. Excessive fuel flow

92. During dry motoring which should be “on” positiona. Fuel boost pumpb. Fuel shut off valve c. Ignition switchd. Generator

93. If the turbine engine is unable to reach take off EPR before its EGT limits is reached, this is an indication that the

a. Fuel control must be replaced b. EGT controlled is out of adjustmentc. Compressor may be contaminated or damaged

94. The condition usually occurs during very fast engine acceleration which an over rich mixture is present causing combustion pressure increase until compressor stagnates

a. Flame out (lean)b. Flame out (rich)c. Combustor instabilityd. Both (A) and (B)

95. MTCS regarding water injection in combustion chamber

a. Injection of water into combustion chamber increases the mass flow through out engineb. Pressure and temp drop across turbine so that pressure in tailpipe increase c. It increases combustion chamber life d. All the above

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