10 Feb 2014

JET ENGINE JUNE Session – 2002


1. EGT measuring thermocouples are connected in
(a)    Series
(b)   Parallel
(c)    Series parallel

2. Angle of attack of a propeller is
(a)    Angle between chord line and plane of rotations
(b)   Angle between chord line and relative wind direction
(c)    Angle between chord line and longitudinal axis the aircraft

3. Mark the correct statement
(a)    Geometric pitch is the distance traveled by propeller in one rotations
(b)   Effective pitch is the actual distance traveled by the propeller in on rotations
(c)    Slip is the difference between geometric pitch and effective pitch
(d)   All of the above

4. Mark the correct statement regarding propeller tracking
(a)    Propeller tracking is determining tip position relative to others propeller
(b)   Static balancing of propeller
(c)    Dynamic balancing of propeller
(d)   All of the above

5. Mark the correct statement
(a)    In alpha range blade angle is controlled by governor

6. Compressor blades are attached with disc
(a)    Dove tail
(b)   Fir tree with various locking
(c)    -------------------------
(d)   as above (a) & (b)

7. Reduced cooling air requirements by 50 percent and decreased wt. By 20% is in which system
(a)    Airflim cooling
(b)   Transpiration cooling
(c)    Impergement cooling
(d)   Finwall

8. Mark correct statement regarding gas turbine igniter
(a)    Gap is more engine to reciprocating because operating provision
(b)   As (a) and less fouling problem
(c)    As (b) and high energy
(d)   As (c) and

Condition lever (propeller lever) controls – free power turbine (Nf)
Power lever (Throttle) controls  - FCU & has generator turbine (N8)
If instruction indicating high / rise then compressor combination
If instruction indicating low / decrease then turbine de effectors

9. Shrouding of turbine blades
(a)    Reduces tip loss
(b)   As (a) prevent excessive vibration
(c)    As (b) and prevent twisting
(d)   As (c) and operate cool as extra mass in tip at reduced speed 

10. Mark correct statement
(a)    Thrust reverse is used in the fan discharge
(b)   50% reverse thrust provided 35 to 50%
(c)    Core engine exhaust is used for forward thrust
(d)   All the above

11. Wet thrust rating is
(a)    Water injection is on
(b)   Cooling period of engine
(c)    Water injection off
(d)   Diffuser

12. Water is injected in compressor inlet and difficult then
(a)    Surge line shifts down
(b)   Surge line shifts away

13. Speed droop is common to all mechanical governors to reduce these problems
(a)    Use a weaker spring
(b)   Make metering valve narrow radially
(c)    Decrease pressure difference across metering valve
(d)   All of the above

14. Mark the correct statement
(a)    Paper cartage type filter used in low preside
(b)   As 1 and screen disc type filter used I hi pr side
(c)    As 2 and
(d)   All of the above

15. For lubrication
(a)    Hi viscosity index oil lis required
(b)   Hi acidity oil is used
(c)    Hi pour point oil is used
(d)   All of the above


16. Mark the correct and statement
(a)    Scavenger pump is centrifugal type of the larger capacity
(b)   Pr pump is centrifugal type
(c)    Scavenger pump capacity is smaller than Pr. Pump
(d)   Both pump are gear type

17. Pressure relief valve pr I equipped with centrifugal boast arrangement
(a)    Boost pump pressure
(b)   Main pump pr
(c)    Filter pr
(d)   All of the above

18. In starter generator
(a)    Two field winding are used
(b)   One common armature is used
(c)    Starter is used for starting of generator for electrical power
(d)   All of the above

19. In gas turbine engine
(a)    Starter is disconnected as soon as light off
(b)   Starter is on to give specified speed to engine

20. In performance monitor ring all parameter are in increasing order then it shows failure
(a)    Turbine
(b)   Compressor
(c)    Combustion
(d)   In let guidvave

21. During starting fire, fire extinguisher is discharge
(a)    Engine is cleaned
(b)   Engine replaced and sent to shape

22. Blending is done to
(a)    Recountering the blade

23. For the maintenance purpose engine is divide in the two section, in hot section
(a)    Turbine combustion exhaust nozzle
(b)   Turbine, diffuser, exhaust nozzle
(c)    HP compressor, combustion, exhaust nozzle
(d)   HP compressor, combustion, turbine





24. FCU senses
(a)    Rpm
(b)   As I and CDP
(c)    As 2 and EDP
(d)   AS 3 AND cip

25. In helicopter which engine is used
(a)    Turbo shaft
(b)   Turbo fan
(c)    Free power turbine (N1)
(d)   Above 1 & 3

26. Advantage of centrifugal compressor
(a)    Hi pr ratio per stage

27. In convergent nozzle used in supersonic speed
(a)    Pr. Increased volume decreased
(b)   Velocity increased

28. Bleeding check
(a)    Bleed valve closed
(b)   Bleed valve open
(c)    Variable stator vane close

29. TSFC is
(a)    Directly proportional to compression ration
(b)   Indirectly

30. Mark correct statement
(a)    Thrust due to pr fall is more than thrust increase due to temperature fall

31. Mark correct statement
(a)    Most compression engines using annular combustion chamber
(b)   Can – annular is best efficient

32. Which one is fuel flow rate indicator without motor
(a)    Vane type
(b)   Impeller – turbine type

33. Mark the correct statement
(a)    Red radial line is maximum permissible range

34. In two wire thermal switch fire detecting
(a)    Open circuit will give indication


35. In modern vibration indication system
(a)    It consists of pick – up, signal conditional indicator
(b)   Later – piezoelectric – acceleration
(c)    Later – electromechanical velocity

36. Rhumble occurs
(a)    P & D valve malfunction
(b)   FCU malfunction
(c)    Fuel nozzle partially clogged
(d)   All of above
37. Which component is not mounted on engine
(a)    Boost pump
(b)   Pressure pump
(c)    P & D valve

38. Mark correct statement regarding oil pressure indicating system
(a)    Thermocouple
(b)   Autosyn
(c)    Temperature buld

39. Anti icing valve is used for
(a)    To avoid ice formation
(b)   -----
(c)    ----
(d)   ---

40. In fuel metering valve
(a)    Orifice area is varied
(b)   A constant fuel pressure across valve
(c)    1 2 2 are correct
(d)    -------

41. Which is fire-extinguishing agent
(a)    Freon
(b)   Bromochloro difloromethane
(c)    Bromo fluoromethane
(d)   All of the above

42. Triming is carried out when
(a)    FCU is changed
(b)   Specific gravity of fuel
(c)    For performance recovery
All of the above