DGCA & EASA Module 15 : Part-14 Engine Indication Systems Question

DGCA & EASA Module 15 : Part-14 Engine Indication Systems Question-Answer

1. The compensation device on an E.G.T system must be re-calibrated after.

A. each time a part of the system is replaced.

B. does not need calibration.

C. manufacture and overhaul.

Ans : does not need calibration.

Explanation: The compensation device is an automatic device Page 140 Rolls Royce book refers.

2. When testing an E.G.T system.

A. the O.A.T is always taken into consideration.

B. the O.A.T is neglected.

C. O.A.T is only taken into consideration when over20°C.

Ans : the O.A.T is always taken into consideration.

Explanation: To test the system the test set has to trimmed for ambient temperature, as the system when in operation is adjusted for ambient temperature by the compensating resistor. This is clearly stated in the B 737 AMM.

3. What is the Engine Pressure Ratio (E.P.R.) used for?.

A. To limit the maximum exhaust gas temperature.

B. To indicate the thrust produced by the engine.

C. As a cross check for minimum acceptable thrust.

Ans : To indicate the thrust produced by the engine.

Explanation: NIL.

4. What happens when bulb type thermometer resistive element goes open circuit?.

A. Reads less than ambient.

B. No reading given.

C. Reads more than ambient.

Ans : Reads more than ambient.

Explanation: NIL.

5. On an E.G.T thermocouple system, the hot junction.

A. is placed up stream of the combustion chamber.

B. is placed in cockpit.

C. is placed downstream of the combustion chamber.

Ans : is placed downstream of the combustion chamber.

Explanation: NIL.

6. On an RPM system using a synchronous generator, the pointer is deflected by.

A. a potentiometer.

B. a Wheatstone bridge.

C. an AC servomotor.

Ans : an AC servomotor.

Explanation: Jepperson Gas Turbine Powerplants Page 12-13 refers.

7. Torque pressure is usually read from a.

A. torque meter.

B. direct reading pressure gauge.

C. tension gauge.

Ans : direct reading pressure gauge.

Explanation: Jepperson Gas Turbine Powerplants Page12-21 refers.

8. The drag cup in a tacho-generator is balanced by.

A. calibrated hairspring.

B. adjustable counterbalance weights.

C. adjustment screw.

Ans : calibrated hairspring.

Explanation: Jepperson Gas Turbine Powerplants Page 12-14 refers.

9. Fuel flow indication is taken from.

A. after the H.P pump.

B. after either H.P Pump or LP Pump.

C. after the LP pump.

Ans : after either H.P Pump or LP Pump.

Explanation: Vane type flowmeters are usually in the LP Supply. Integrated flowmeters in the H.P supply.

10. What power is required for E.G.T gauge indication?.

A. No power - it is self generating.

B. 115V AC.

C. 28V DC.

Ans : No power - it is self generating.

Explanation: Jeppesen Gas Turbine Powerplants Page 12-5 Refers.

11. A Bourdon tube instrument may be used to indicate.

A. position and quantity.

B. pressure and temperature.

C. pressure, temperature, position and quantity.

Ans : pressure and temperature.

Explanation: NIL.

12. What instrument on a gas turbine engine should be monitored to minimize the possibility of a 'hot' start?.

A. RPM indicator.

B. Turbine inlet temperature.

C. Torquemeter.

Ans : Turbine inlet temperature.

Explanation: Jeppesen A&P Powerplant Textbook 4-5.

13. oil temperature thermocouples are usually constructed of.

A. iron constantan.

B. alumel constantan.

C. chromel alumel.

Ans : iron constantan.

Explanation: NIL.

14. The RPM indication of a synchronous AC motor tachometer is governed by the generator.

A. current.

B. frequency.

C. voltage.

Ans : frequency.

Explanation: NIL.

15. Instruments that measure relatively high fluid pressures, such as oil pressure gauges, are usually what type?.

A. Bourdon tube.

B. Vane with calibrated spring.

C. Diaphragm or bellows.

Ans : Bourdon tube.

Explanation: NIL.

16. Instruments that provide readings of low or negative pressure, such as manifold pressure gauges, are usually what type?.

A. Diaphragm or bellows.

B. Vane with calibrated spring.

C. Bourdon tube.

Ans : Diaphragm or bellows.

Explanation: NIL.

17. In what units are gas turbine engine tachometers calibrated?.

A. Percent of engine pressure ratio.

B. Percent of engine RPM.

C. Actual engine RPM.

Ans : Percent of engine RPM.

Explanation: Jeppesen A&P Powerplant Textbook 4-2.

18. In a turbine engine, where is the turbine discharge pressure indicator sensor located?.

A. At a location in the exhaust cone that is determined to be subjected to the highest pressures.

B. Immediately aft of the last turbine stage.

C. At the aft end of the compressor section.

Ans : Immediately aft of the last turbine stage.

Explanation: NIL.

19. The exhaust gas temperature (E.G.T ) indicator on a gas turbine engine provides a relative indication of the.

A. turbine inlet temperature.

B. temperature of the exhaust gases as they pass the exhaust cone.

C. exhaust temperature.

Ans : turbine inlet temperature.

Explanation: Jeppesen A&P Powerplant Textbook 4-5.

20. Engine pressure ratio is determined by.

A. dividing engine inlet total pressure by turbine outlet total pressure.

B. multiplying engine inlet total pressure by turbine outlet total pressure.

C. dividing turbine outlet total pressure by engine inlet total pressure.

Ans : dividing turbine outlet total pressure by engine inlet total pressure.

Explanation: NIL.

21. A red triangle, dot, or diamond mark on an engine instrument face or glass indicates.

A. the maximum limit for high transients such as starting.

B. a restricted operating range.

C. the maximum operating limit for all normal operations.

Ans : the maximum limit for high transients such as starting.

Explanation: Jeppesen A&P Powerplant Textbook 4-5.

22. What is the primary purpose of the tachometer on an axial compressor turbine engine?.

A. Monitor engine RPM during cruise conditions.

B. Monitor engine RPM during starting and to indicate overspeed conditions.

C. It is the most accurate instrument for establishing thrust settings under all conditions.

Ans : Monitor engine RPM during starting and to indicate overspeed conditions.

Explanation: Jeppesen A&P Powerplant Textbook 4-4.

23. Engine pressure ratio is the total pressure ratio between the.

A. front of the engine inlet and the aft end of the compressor.

B. front of the compressor and the rear of the turbine.

C. aft end of the compressor and the aft end of the turbine.

Ans : front of the compressor and the rear of the turbine.

Explanation: Jeppesen A&P Powerplant Textbook 4-4.

24. On an aircraft turbine engine, operating at a constant power, the application of engine anti-icing will result in.

A. an increase in E.P.R.

B. noticeable shift in E.P.R.

C. a false E.P.R reading.

Ans : noticeable shift in E.P.R.

Explanation: Jeppesen A&P Powerplant Textbook 4-4.

25. The indicator of a tachometer system is responsive to change in.

A. voltage.

B. frequency.

C. current flow.

Ans : frequency.

Explanation: Jeppesen A&P Powerplant Textbook 4-4.

Click Here For : DGCA & EASA Module 15 : Part-15 Engine Power Augmentation Systems Question

26. The fuel flow indication data sent from motor driven impeller and turbine, and motorless type fuel flow transmitters is a measure of.

A. fuel mass flow.

B. fuel volume flow.

C. engine burner pressure drop.

Ans : fuel mass flow.

Explanation: Jeppesen A&P Powerplant Textbook 4-4.

27. In addition to fuel quantity, a computerized fuel system (C.F.S) with a totalizer indicator provides indication of how many of the following?.

A. Fuel flow rate, Fuel used since reset or initial start up, Fuel time remaining at current power setting.

B. Fuel flow rate, Fuel used since reset or initial start up, Fuel time remaining at current power setting, Fuel temperature.

C. Fuel flow rate, Fuel used since reset or initial start up, Fuel temperature.

Ans : Fuel flow rate, Fuel used since reset or initial start up, Fuel time remaining at current power setting.

Explanation: Jeppesen A&P Powerplant Textbook 4-4.

28. The fuel flow indicator rotor and needle for a motor impeller and turbine indicating system is driven by.

A. direct coupling to the motor shaft.

B. an electrical signal.

C. a mechanical gear train.

Ans : an electrical signal.

Explanation: Jeppesen A&P Powerplant Textbook 4-4.

29. Motor driven impeller and turbine fuel flow transmitters are designed to transmit data.

A. using aircraft electrical system power.

B. mechanically.

C. by fuel pressure.

Ans : using aircraft electrical system power.

Explanation: NIL.

30. What unit in a tachometer system sends information to the indicator?.

A. The two phase AC generator.

B. The three phase AC generator.

C. The synchronous motor.

Ans : The three phase AC generator.

Explanation: Jeppesen Aircraft Gas Turbine Powerplants 12-13.

31. Engine oil temperature gauges indicate the temperature of the oil.

A. entering the oil cooler.

B. entering the engine.

C. in the oil storage tank.

Ans : entering the oil cooler.

Explanation: Rolls Royce book fig 8-7.

32. Thermocouple leads.

A. may be repaired using solderless connectors.

B. are designed for a specific installation and may not be altered.

C. may be installed with either lead to either post of the indicator.

Ans : are designed for a specific installation and may not be altered.

Explanation: NIL.

33. Why do helicopters require a minimum of two synchronous tachometer systems?.

A. One indicates engine RPM and the other tail rotor RPM.

B. One indicates main rotor RPM and the other tail rotor RPM.

C. One indicates engine RPM and the other main rotor RPM.

Ans : One indicates engine RPM and the other main rotor RPM.

Explanation: NIL.

34. If the thermocouple leads were inadvertently crossed at installation, what would the E.G.T gauge pointer indicate?.

A. Moves off scale on the high side of the meter.

B. Moves off scale on the zero side of the meter.

C. Normal temperature for prevailing condition.

Ans : Moves off scale on the zero side of the meter.

Explanation: NIL.

35. A common type of electrically operated oil temperature gauge utilizes.

A. either a wheatstone bridge or ratiometer circuit.

B. a thermocouple type circuit.

C. vapour pressure and pressure switches.

Ans : either a wheatstone bridge or ratiometer circuit.

Explanation: NIL.

36. The indication on a thermocouple-type E.G.T indicator is produced by.

A. resistance changes in two dissimilar metals.

B. a difference in the voltage between two dissimilar metals.

C. a current generated by the temperature difference between dissimilar metal hot and cold junctions.

Ans : a current generated by the temperature difference between dissimilar metal hot and cold junctions.

Explanation: NIL.

37. What is the Engine Pressure Ratio (E.P.R) used to indicate?.

A. The power produced by the engine.

B. The thrust produced by the engine.

C. As a cross check for minimum acceptable thrust.

Ans : The thrust produced by the engine.

Explanation: Normally used on High Bypass Engines.

38. Where is Turbine Outlet Temperature (T.O.T) measured?.

A. Upstream of the turbine.

B. Downstream of the turbine.

C. In the combustion chamber.

Ans : Downstream of the turbine.

Explanation: It can be in the jet pipe or more normally today in between turbine stages or even within NGV's.

39. A thermocouple indicator is basically a.

A. milliammeter.

B. millivoltmeter.

C. milliohmeter.

Ans : millivoltmeter.

Explanation: A thermocouple generates an E.M.F between hot and cold junction, hence the gauge is a millivoltmeter.

40. A thermocouple indicator is connected to the.

A. cold junction.

B. hot junction.

C. difference between the hot junction and the cold junction.

Ans : cold junction.

Explanation: Pallett Aircraft Instruments and Integrated Systems Page 362 Refers.

41. Thrust in a high bypass fan engine is indicated by.

A. N3 RPM or P1/P4 ratio.

B. N1 RPM or N3 RPM.

C. N1 RPM or E.P.R.

Ans : N1 RPM or E.P.R.

Explanation: RR and P&W tend to use E.P.R. GE use N1.

42. How is the N1 and N2 measured on a triple spool engine?.

A. Tachometer connected to the internal gearbox.

B. Tachometer connected to the external gearbox.

C. Pulse type speed probes.

Ans : Pulse type speed probes.

Explanation: Jeppesen Gas Turbine Powerplants Page 12-16 refer. Fig 12-10B shows the system used on Rolls Royce triple spool engines.

43. Modern oil pressure servo transmitters sense.

A. absolute pressure.

B. H.P oil pressure.

C. differential pressure.

Ans : differential pressure.

Explanation: Jeppesen Gas Turbine Powerplants Page 12-28 refer.

44. E.G.T thermocouples are usually made of.

A. nickel and platinum.

B. chromel and platinum.

C. chromel and alumel.

Ans : chromel and alumel.

Explanation: Jeppesen Gas Turbine Powerplants Page 12-4 refer.

45. Thrust in a high bypass engine is indicated by measuring.

A. N3 RPM.

B. neither of the above, thrust is not indicated in flight.

C. fuel flow.

Ans : neither of the above, thrust is not indicated in flight.

Explanation: The only indication of power in flight is E.P.R or, for a high bypass engine, N1 RPM.

46. What power supply is required for a thermocouple system to work?.

A. Alternating current.

B. Direct current.

C. Neither of the above.

Ans : Neither of the above.

Explanation: Rolls Royce the Jet engine Page 139 refers.

47. In a thermocouple temperature sensing system, what is the purpose of the compensating resistor?.

A. To correct for varying ambient temperatures at the hot junction.

B. To correct for varying ambient temperatures at the cold junction.

C. To standardise the reading for different engine types.

Ans : To correct for varying ambient temperatures at the cold junction.

Explanation: Rolls Royce The Jet Engine page 140 refers.

48. In a tachometer generator.

A. the frequency output is inversely proportional to engine speed.

B. frequency output is proportional to engine speed.

C. the frequency output is constant.

Ans : frequency output is proportional to engine speed.

Explanation: Pallett Aircraft Instruments and Integrated Systems P348 refers.

49. Vibration pick-ups are located.

A. on both fan and turbine cases.

B. on the fan/compressor case.

C. on the turbine case.

Ans : on both fan and turbine cases.

Explanation: Can be on one or both, depending upon the engine.

50. In a capacitive type fuel quantity indicating system the tank units are connected in.

A. series.

B. parallel.

C. series/parallel.

Ans : parallel.

Explanation: EHJ Pallett Aircraft Instruments and Integrated Systems page 337 refers.

51. Torque measurement in a gas turbine engine is.

A. not always reliable.

B. highly reliable.

C. required only when the turbine drives a propeller.

Ans : required only when the turbine drives a propeller.

Explanation: Rolls Royce The Jet Engine Page 138 refers.

52. Vibration signals, when picked up,.

A. go straight to indicator.

B. go through half wave rectifier to indicator.

C. the frequencies are filtered to exclude unwanted frequencies.

Ans : the frequencies are filtered to exclude unwanted frequencies.

Explanation: The filters in the Vibro-meter use rotor speed to identify vibration frequencies.

53. E.G.T is displayed in.

A. Kelvin.

B. degrees centigrade.

C. degrees Fahrenheit.

Ans : degrees centigrade.

Explanation: E.G.T is always measured in centigrade.

54. N2 is taken from.

A. a speed transducer on the fan rear frame.

B. a tachometer attached on the N1 gearbox.

C. a tachometer on the accessory gearbox.

Ans : a tachometer on the accessory gearbox.

Explanation: The N2 gearbox is driven by the N2 compressor. A single winding of an alternator can be used for the speed signal as an alternative to a.

55. Engine vibration is monitored using.

A. electromechanical devices.

B. Fenwall type sensors.

C. piezoelectric accelerometer.

Ans : piezoelectric accelerometer.

Explanation: Piezoelectric devices convert force(from the vibration) to a milli-volt output.

56. Integrating fuel flow gives.

A. average fuel flow.

B. total fuel consumed.

C. fuel flow and acceleration.

Ans : total fuel consumed.

Explanation: An Integrator is incorporated in a fuel flow-meter to give a total fuel used figure.

57. The gauge on a bulb type temperature indicator shows zero. This could be caused by.

A. open circuit in the wiring.

B. temperature bulb going open circuit.

C. two cables shorting together by the sensor.

Ans : two cables shorting together by the sensor.

Explanation: Pallett Instruments and Integrated systems Page 318 refers. A short will remove all power from both windings and the pointer will go tominimum scale.

58. In a thermocouple system, the size of the E.M.F that is produced is a result of.

A. the difference between the hot and cold junction.

B. the cold junction only.

C. the hot junction only.

Ans : the difference between the hot and cold junction.

Explanation: The E.M.F is a result of the difference between the 2 junctions.

59. A ballast resistor is fitted.

A. in parallel, to give identical readings for all engines.

B. in series, to give identical resistance values for all engines.

C. in series, to give identical resistance values to all airframes.

Ans : in series, to give identical resistance values to all airframes.

Explanation: NIL.


Click Here For : DGCA & EASA Module 15 : Part-15 Engine Power Augmentation Systems Question