Vayudoot Aviation

1. Torque can be calculated in a torquemeter system by the measurement

Of the difference between 2 phonic wheels connected to the transmission

Of the frequency of a phonic wheel connected to the planet gears of an epicyclic gearbox

Of the amount of light through a gear wheel connected to the transmission

Of the oil pressure resisting lateral movement of the gearing in an epicyclic reduction gearbox

2. Among these instruments, which one uses aneroid capsules?

fuel pressure sensor

oil pressure sensor

oil thermometer

air intake pressure sensor

3. Two main indications used to evaluate a turbojet thrust are

fan rotational speed (N1 ) or EPR

high pressure turbine rotational speed or EPR

rotational speed of the fan (N1 ) or the total pressure at the outlet of the low-pressure turbine

fan rotational speed (N1 ) or total pressure at the high-pressure compressor outlet

4. The principle upon which flowmeters (mass flow) most commonly used today work, is to measure:

The Kinetic energy transferred

The Volume and Viscosity of the fuel

Density and Dielectric constant of the fuel

The Pressure and Temperature of the fuel

5. On an EICAS display what does the yellow arc on the temperature gauge signify

Forbidden operating range

Frequent operating range

Exceptional operating range

6. The power output of a turbo-propeller aircraft is measured by the amount of torque being produced. The indication can be in which of the following units. 1. Newton metres 2. PSI 3. Percentage 4. Pounds feet 5. EPR

1,2,3,4

1,2,3,5

1,2,3,4,5

2,3,4,5

7. What is used to measure gas turbine inlet pressure

Aneroid capsule

Bellows

Bourdon Tube

Differential capsule

8. The Bourdon Tube is used in

Temperature probes in front of the engine

Smoke detectors

Vibration detectors

Pressure measurement

9. What does a bourdon tube measure

Temperature

Quantity

Capacitance

Pressure

10. A capacitive type gauging system may measure mass due to

fuel dielectric constant being twice that of air and proportional to density

fuel dielectric constant being equal to that of air and proportional to1/density

fuel dielectric constant being twice that of air and proportional to 1/density

fuel dielectric constant being equal to that of air and proportional to density

11. The principles used in an electrical RPM indicating system are:- 1. Tacho probe and phonic wheel 2. DC generator producing AC 3. 3 phase AC generator driving a 3 phase AC motor 4. Single phase AC generator driving a single phase AC motor

2 and 4

1 and 4

2 and 3

1 and 3

12. What type of sensor is used to measure the output of a low pressure booster pump

aneroid capsule

bourdon tube

differential capsule

bellows

13. A supercharged aircraft is climbing at its maximum permitted boost of 8 psi (16in.Hg) from sea level to its full throttle height of 10,000 feet. If sea level pressure is 29.92in.Hg , when the aircraft reaches 5000 feet, where the pressure is 24.72in.Hg, what will be the approximate indication on the MAP gauge.

33 in Hg

46 in Hg

41 in Hg

18 in Hg

14. An RPM gauge has a red line at the upper end of the green arc, in the middle of the green arc is a smaller red arc. What is the significance of this smaller red arc

it indicates an RPM that must not be used continuously because of the increased vibration level from the engine/propeller

it is maximum continuous RPM

it indicates an RPM that must not be used continuously because there is insufficient cooling air for the engine

it is the RPM at which there is an increased likelihood of oil leakage

15. How will a system failure warning be shown to the pilot in the ECAM system

The failure will appear as a wording on the screen

The master warning will illuminate and the primary screen will display a check list while the secondary shows a graphical display of the problem

The Engine parameter displays will be replaced by the Flight Mode screen

The master warning caption will illuminate and the pilot will manually select failure mode.

16. In an ECAM system if a caution message appears the system will

display a diagrammatic view of the affected system

illuminate the page number that requires to be selected

will cause the relevant buttons to light up

will alert the pilot by an audible warning only

17. What does the yellow band on an EICAS generated engine gauge indicate?

Maximum operating range

Warning limit

Precautionary operating range

Normal range

18. How can temperature be measured 1. Resistance 2. Mercury 3. Thermocouple 4. Reactance

1,2,3

1,2,3,4

1,2,4

1,3,4

19. A millivoltmeter measuring electromotive force between a hot and a cold junction of a thermocouple can be graduated to read temperature if: -

the hot junction is maintained at 15 degrees C

the cold junction is maintained at 15 degrees C

the hot junction is kept at a constant temperature

the cold junction is maintained at a constant temperature

20. The torquemeter is an instrument

Giving the power from the propeller by direct reading

Giving the power available by the engine

Allowing automatic synchronisation of the engines

Allowing the determination of the power from the propeller by using a formula which is a function of the RPM

21. If both displays of an EICAS system fail what information will be displayed on the standby engine indicator

N1,EPR, EGT

N1,EPR,N2

EGT,N1, FF

N2,EPR, EGT

22. What are the disadvantages of an electrical float fuel quantity measuring system 1 Attitude 2 Acceleration 3 Temperature 4 Ambient pressure 5 Needs an AC power supply

2,3,4,5

1,2,3

1,2,5

1,2,3,4,5

23. If one probe of a multi-sensor T.G.T. system failed , the reading would:

decrease by 20 – 30 degrees C

be practically unaffected

fall to zero

increase by 20 – 30 degrees C

24. An advisory message on the EICAS system screen would be

displayed in red, normally on the upper screen , and requiring immediate corrective action

displayed in amber, normally on the upper screen with aural warnings .

displayed in amber, normally on the upper screen, indented one space to the right.

displayed in amber on the lower screen with associated caution lights and aural tones

25. Where very accurate temperature indication is required the indicator used will be

moving coil

galvanometer

ratiometer

direct reading

26. To measure the fuel quantity on a heavy aircraft we use: 1 capacitor gauges 2 electric gauges with round floats 3 the indication can directly be indicated as a mass 4 the indication can not be indicated as a mass The combination of all correct statements is

1,3

2,3

1,4

2,4

27. The working principle of a capacitive fuel contents gauging system is based upon

height of fuel

volume of fuel

changes in capacitance

dielectric value

28. The most significant parameters and the most important that express the thrust of a gas turbine engine are

N2 and FF

EGT or N2

FF and EGT

N1 and EPR

29. What is a synchroscope used for

allowing the pilot to adjust several engines to the same RPM

reducing vibration

viewing the underside of the aircraft during flight

putting the propellers in phase

30. Total Air Temperature (TAT) is equal to

RAT + ram rise

SAT – RAT

RAT + friction rise

SAT + ram rise

31. A small turbine placed in the flow of fuel to the burners of a Gas Turbine engine measures

Volume flow by the measurement of reactance

Volume of flow by the measurement of magnetic impulses

Mass flow by the measurement of magnetic impulses

Mass flow by the measurement of frequency

32. A vibration meter measures

acceleration in g

frequency in Hz

period in seconds

amplitude at a given frequency

33. The principle of the fuel-monitoring device giving the fuel burnt is

integration of instantaneous flow

capacitance variation of a capacitor

difference of indication according to departure value

multiplying flight time by fuel consumption

34. If the intake probe of an EPR system becomes blocked with ice this will cause the EPR gauge to

be unaffected

read zero

under-read during take off

35. An aircraft has a compensated capacitance fuel contents gauging system and is refuelled so that the total fuel contents are 76000kg at a temperature of 18 degrees C and an S.G. of 0.81. Whilst the aircraft is parked the temperature increases to 26 degrees C and the S.G. becomes 0.80. The indicated fuel contents have.

increased by 5%

decreased by 5%

increased by 10%

remained the same

36. On a modern twin spool turbofan, the main handling parameter is

a rotational speed and a temperature

the rotational speed of the low-pressure compressor

the rotational speed of the high-pressure compressor

the temperature upstream the turbine or EGT

37. Which of the following are used to measure temperature 1. thermocouple 2. resistance 3. reactance 4. mercury

1,2, & 4

2,3, & 4

1,3,& 4

1,2,3,4

38. A cylinder head temperature measuring system in a piston engine has a sensor

One in the hottest running cylinder

One in the coolest running cylinder

One in each of the two banks of cylinders in a horizontally opposed engine

One in each cylinder head to average the temperature

39. The capacitor gauge principle is based on

variation of capacitance by volume measure at the probe

variation of capacitance of a capacitor with the nature of the dielectric

variation of the EMF in a wheastone bridge

variation of outflow and couple in the system

40. The working principle of mass flow meters mostly used now days, is to measure in their system

the temperature and pressure of the fuel

volume mass and dielectric value of fuel

kinetic energy transmitted

the volume and viscosity of the fuel

41. A volumetric fuel flow meter is different to a mass flow meter because the mass flow meter compensates for

density

pressure

volume

dielectric

42. The measure of a torque can be made by measuring:

oil pressure at a fixed crown of an epicyclical reduction gear of the transmission box

the frequency of a phonic wheel linked to a transmission shaft

the amount of light through a gear linked to a transmission shaft

the frequency difference between two phonic wheels linked to a transmission shaft

43. In a Turbojet thrust is measured by

Fan Speed (N1) and Turbine Inlet Pressure

N1 and EPR

Compressor outlet pressure and jet pipe pressure

Compressor inlet pressure and combustion chamber pressure

44. The electrical tacho generator system uses

single phase a.c. whose frequency varies with the speed of the engine delivered to a single phase synchronous motor and drag cup.

three phase a.c. whose frequency varies with the speed of the engine delivered to a three phase synchronous motor (squirrel cage) and drag cup.

A tacho probe and phonic wheel measuring speed and sending information to a squirrel cage motor and drag cup

Single phase d.c. whose frequency varies with speed of the engine converted to a square wave pulse delivered to a servo driven instrument

45. Advantage of a ratiometer type measuring circuit is

No external power supply is required

Simple

Very Accurate

Changes indication if voltage changes

46. The advantage of a ratiometer is

it requires an ac voltage and therefore has no commutator.

does not suffer from errors due to variations of supply voltage

is calibrated at sea level and will be inaccurate at high altitudes

doesn’t require an electrical supply

47. Among the following parameters: EGT EPR FF N1 N2 Oil pressure Fuel pressure The ones that can be used to monitor a gas turbine thrust setting are

EGT, EPR, FF, High-pressure fuel

EGT, N1, N2, oil pressure

EGT, N1, FF, EPR

fuel pressure, N1, N2, oil pressure

48. During the take-off run , the effect of increasing airspeed is to cause the EPR indication to

decrease

remain constant

increase

increase and subsequently decrease

49. For a capacitor gauge: 1 the fuel dielectric value is half that of air 2 the fuel dielectric value varies proportionally to the temperature of the fuel 3 the probes are connected in parallel 4 fuel dielectric value varies inversely with the fuel level 5 the gauge accuracy is within 2% The correct statements are:

3,4

2,3

3,5

1,2

50. In a three phase tachometer installation: 1 the transmitter is a DC generator 2 we measure an EMF proportional to the driving speed of the transmitter 3 we measure a frequency proportional to the driving speed of the transmitter 4 the receiver is a galvometer 5 the receiver is an synchronised motor driving a magnetic tachometer The correct statements are

2,5

1,2

1,4

3,5

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