DGCA & EASA Module 15 : Part-10 Engine Lubrication Systems Question

DGCA & EASA Module 15 : Part-10 Engine Lubrication Systems Question-Answer

1. The oil pressure in the cooler is.

A. same as the fuel pressure.

B. lower than the fuel pressure.

C. higher than the fuel pressure.

Ans : higher than the fuel pressure.

Explanation: NIL.

2. When rotating, the gear type oil pump.

A. draws oil into the pump and carries it round between the gear teeth and casing.

B. draws oil into the pump and through the intermeshing gears to the outlet.

C. draws oil into the pump, half being carried around between pump and casing, the other half passing between the gears to the outlet.

Ans : draws oil into the pump and carries it round between the gear teeth and casing.

Explanation: NIL.

3. A scavenge filter is incorporated in a gas turbine lubrication system to.

A. protect the scavenge pump.

B. protect the oil cooler.

C. protect the pressure pump.

Ans : protect the pressure pump.

Explanation: RR The Jet Engine (New Edition) Page 181.

4. The working fluid of a constant speed drive (C.S.D) is.

A. from separate tank.

B. within the unit.

C. taken from the engine lubrication system.

Ans : within the unit.

Explanation: C.S.Ds and I.D.Gs have their own self contained oil system.

5. What is the possible cause when a turbine engine indicates no change in power setting parameters, but oil temperature is high?.

A. High scavenge pump oil flow.

B. Turbine damage and/or loss of turbine efficiency.

C. Engine main bearing distress.

Ans : Engine main bearing distress.

Explanation: NIL.

6. How is engine oil usually cooled?.

A. By a fuel/oil cooler.

B. By ram air.

C. By bleed air.

Ans : By a fuel/oil cooler.

Explanation: Jeppesen Gas Turbine Powerplants Page 6-25 Refers.

7. What filters are used to protect oil pressure spray jets?.

A. Felt/paper filters.

B. In-line thread filters.

C. Micronic filters.

Ans : In-line thread filters.

Explanation: RR book page 82 states that thread type filters are used as last chance filters.

8. The chip detector in the oil system is a.

A. window in the pump casing.

B. window in the oil pump.

C. magnetic plug in the return line.

Ans : magnetic plug in the return line.

Explanation: Jeppesen Gas Turbine Powerplant Page 6-26 refers.

9. When rotating, the gyroter type oil pump.

A. oil is drawn into the pump and through the intermeshing gears to the outlet.

B. oil is drawn into the pump, half being carried around between pump and casing, the other half passing between the gears to the outlet.

C. draws oil into the pump and carries it round between the gear teeth and casing.

Ans : draws oil into the pump and carries it round between the gear teeth and casing.

Explanation: Jeppesen Aircraft Gas Turbine Powerplant Page 6-14 Refers.

10. Oil picks up the most heat from which of the following turbine engine components?.

A. Compressor bearing.

B. Rotor coupling.

C. Turbine bearing.

Ans : Turbine bearing.

Explanation: Jeppesen A&P Technician Propulsion Textbook 9-31.

11. In a jet engine which uses a fuel oil heat exchanger, the oil temperature is controlled by a thermostatic valve that regulates the flow of.

A. both fuel and oil through the heat exchanger.

B. oil through the heat exchanger.

C. fuel through the heat exchanger.

Ans : oil through the heat exchanger.

Explanation: Jeppesen A&P Technician Propulsion Textbook 9-32.

12. What is the purpose of the last chance oil filters?.

A. To filter the oil immediately before it enters the main bearings.

B. To assure a clean supply of oil to the lubrication system.

C. To prevent damage to the oil spray nozzle.

Ans : To prevent damage to the oil spray nozzle.

Explanation: Jeppesen A&P Technician Propulsion Textbook 9-30.

13. Which of the following is a function of the fuel oil heat exchanger on a turbojet engine?.

A. Aerates the fuel.

B. Emulsifies the oil.

C. Increases fuel temperature.

Ans : Increases fuel temperature.

Explanation: Jeppesen A&P Technician Propulsion Textbook 9-32.

14. At cruise RPM, some oil will flow through the relief valve of a gear type engine oil pump. This is normal as the relief valve is set at a pressure which is.

A. higher than pressure pump capabilities.

B. lower than the pressure pump capabilities.

C. lower than the pump inlet pressure.

Ans : lower than the pressure pump capabilities.

Explanation: NIL.

15. What will happen to the return oil if the oil line between the scavenger pump and the oil cooler separates?.

A. Oil will accumulate in the engine.

B. The scavenger return line check valve will close and force the oil to bypass directly to the intake side of the pressure pump.

C. The return oil will be pumped overboard.

Ans : The scavenger return line check valve will close and force the oil to bypass directly to the intake side of the pressure pump.

Explanation: NIL.

16. The oil dampened main bearing utilized in some turbine engines is used to.

A. dampen surges in oil pressure to the bearings.

B. provide lubrication of bearings from the beginning of starting rotation until normal oil pressure is established.

C. provide an oil film between the outer race and the bearing housing in order to reduce vibration tendencies in the rotor system, and to allow for slight misalignment.

Ans : provide an oil film between the outer race and the bearing housing in order to reduce vibration tendencies in the rotor system, and to allow for slight misalignment.

Explanation: NIL.

17. After making a welded repair to a pressurized type turbine engine oil tank, the tank should be pressure checked to.

A. not less than 5 PSI plus the maximum operating pressure of the tank.

B. not less than 5 PSI plus the average operating pressure of the tank.

C. 5 PSI.

Ans : not less than 5 PSI plus the maximum operating pressure of the tank.

Explanation: Jeppesen A&P Technician Propulsion Textbook 9-37.

18. Possible failure related ferrous metal particles in turbine engine oil cause an (electrical) indicating type magnetic chip detector to indicate their presence by.

A. bridging the gap between the detector center (positive) electrode and the ground electrode.

B. generating a small electric current that is caused by the particles being in contact with the dissimilar metal of the detector tip.

C. disturbing the magnetic lines of flux around the detector tip.

Ans : bridging the gap between the detector center (positive) electrode and the ground electrode.

Explanation: Jeppesen A&P Technician Propulsion Textbook 9-33.

19. What would be the probable result if the oil system pressure relief valve should stick in the open position on a turbine engine?.

A. Increased oil pressure.

B. Decreased oil temperature.

C. Insufficient lubrication.

Ans : Decreased oil temperature.

Explanation: NIL.

20. What is the primary purpose of the oil to fuel heat exchanger?.

A. De aerate the oil.

B. Cool the oil.

C. Cool the fuel.

Ans : Cool the oil.

Explanation: Jeppesen A&P Technician Propulsion Textbook 9-32.

21. Low oil pressure can be detrimental to the internal engine components. However, high oil pressure.

A. has a negligible effect.

B. will not occur because of pressure losses around the bearings.

C. should be limited to the engine manufacturer's recommendations.

Ans : should be limited to the engine manufacturer's recommendations.

Explanation: NIL.

22. What is the primary purpose of the oil breather pressurization system that is used on turbine engines?.

A. Prevents foaming of the oil.

B. Allows aeration of the oil for better lubrication because of the air/oil mist.

C. Provides a proper oil spray pattern from the main bearing oil jets.

Ans : Prevents foaming of the oil.

Explanation: NIL.

23. What type of oil system is usually found on turbine engines?.

A. Dry sump, dip, and splash.

B. Dry sump, pressure, and spray.

C. Wet sump, spray, and splash.

Ans : Dry sump, pressure, and spray.

Explanation: Jeppesen A&P Technician Propulsion Textbook 9-26.

24. How are the teeth of the gears in the accessory section of an engine normally lubricated?.

A. By surrounding the load bearing portions with baffles or housings within which oil pressure can be maintained.

B. By splashed or sprayed oil.

C. By submerging the load bearing portions in oil.

Ans : By splashed or sprayed oil.

Explanation: NIL.

25. Manufacturers normally require turbine engine oil servicing within a short time after engine shutdown primarily to.

A. prevent over servicing.

B. help dilute and neutralize any contaminants that may already be present in the engine's oil system.

C. provide a better indication of any oil leaks in the system.

Ans : prevent over servicing.

Explanation: Jeppersen A&P Technician Powerplant Book Page 9-36.

26. In order to relieve excessive pump pressure in an engine's internal oil system, most engines are equipped with a.

A. vent.

B. relief valve.

C. bypass valve.

Ans : relief valve.

Explanation: NIL.

Click Here For : DGCA & EASA Module 15 : Part-11 Engine Fuel Systems Question

27. The type of oil pumps most commonly used on turbine engines are classified as.

A. positive displacement.

B. constant speed.

C. variable displacement.

Ans : positive displacement.

Explanation: Jeppesen A&P Technician Propulsion Textbook 9-28.

28. If the oil in the oil cooler core and annular jacket becomes congealed, what unit prevents damage to the cooler?.

A. Oil pressure relief valve.

B. Airflow control valve.

C. Surge protection valve.

Ans : Oil pressure relief valve.

Explanation: NIL.

29. What will result if an oil filter becomes completely blocked?.

A. Oil flow to the engine will stop.

B. Oil will flow at the normal rate through the system.

C. Oil will flow at a reduced rate through the system.

Ans : Oil will flow at the normal rate through the system.

Explanation: NIL.

30. A turbine engine dry sump lubrication system of the self contained, high pressure design.

A. stores oil in the engine crankcase.

B. has no heat exchanger.

C. consists of pressure, breather, and scavenge subsystems.

Ans : consists of pressure, breather, and scavenge subsystems.

Explanation: NIL.

31. What is the primary purpose of the hopper located in the oil supply tank of some dry sump engine installations?.

A. To reduce the time required to warm the oil to operating temperatures.

B. To impart a centrifugal motion to the oil entering the tank so that the foreign particles in the oil will separate more readily.

C. To reduce surface aeration of the hot oil and thus reduce oxidation and the formation of sludge and varnish.

Ans : To reduce the time required to warm the oil to operating temperatures.

Explanation: Jeppesen A&P Technician Propulsion Textbook 9-11.

32. What determines the minimum particle size which will be excluded or filtered by a cuno type (stacked disc, edge filtration) filter?.

A. Both the number and thickness of the discs in the assembly.

B. The spacer thickness.

C. The disc thickness.

Ans : The spacer thickness.

Explanation: Jeppesen A&P Technician Propulsion Textbook 9-17.

33. A full flow oil system has.

A. a single fixed minimum oil pressure.

B. a variable oil pressure dependant upon throttle setting.

C. a hot and cold oil pressure limit.

Ans : a variable oil pressure dependant upon throttle setting.

Explanation: This system does not have a pressure regulating valve, only a max pressure relief valve for safety purposes.

34. A felt filter in an oil lubrication system should be.

A. removed and cleaned in M.E.K.

B. removed and replaced with a new filter element.

C. removed and cleaned in a container of lead free petrol.

Ans : removed and replaced with a new filter element.

Explanation: Jeppesen Aircraft Gas Turbines Powerplant page 6-14 refers.

35. What filter is used in a oil scavenge pump in the inlet side of the pump?.

A. Wire wound filter.

B. Threaded filter.

C. Wire mesh filter.

Ans : Wire mesh filter.

Explanation: Rolls Royce The Jet engine page 82 refers to a coarse strainer fatted to the inlet of oil pumps. Wire mesh is considered to be the same thing.

36. A vane type oil pump output is controlled by.

A. outlet pressure against spring pressure.

B. outlet pressure controlling servo.

C. output pressure controlling plate angle.

Ans : outlet pressure against spring pressure.

Explanation: Jeppesen Aircraft gas Turbine Powerplants page 6-10 refers.

37. The sump in a dry sump oil system.

A. is used as a collecting point only.

B. houses all the engine oil.

C. provides lubrication for the main bearings.

Ans : is used as a collecting point only.

Explanation: Dry sumps are scavenged back to the reservoir.

38. A jet engine gear box breather is prevented from leaking oil to atmosphere by the action of.

A. air or oil valve.

B. oil thrower ring and centrifugal force.

C. impeller and centrifugal force.

Ans : impeller and centrifugal force.

Explanation: Refer to page 81 Rolls Royce The Jet Engine for a diagram of a gearbox centrifugal breather.

39. The air-cooled-oil-cooler has an anti-surge valve in order to.

A. protect the cooler.

B. restrict the engine max oil pressure.

C. stop oil draining from the system when the cooler is removed.

Ans : protect the cooler.

Explanation: The term anti surge valve is unusual, an oil pressure relief bypass valve is a better description.

40. A thread type oil seal in a lubrication system.

A. screws oil back into the bearing sump when the shaft rotates

B. has a thread on a stationary portion to prevent fluid leaks.

C. only seals when stationary.

Ans : has a thread on a stationary portion to prevent fluid leaks.

Explanation: This is a type of labyrinth seal, see page 92 of The Jet Engine.

41. The oil system generally used on most modern turboprop engines is.

A. dry sump type.

B. wet sump type.

C. A low pressure system.

Ans : dry sump type.

Explanation: The oil is contained in a separate oil tank.

42. A spur gear pump operating in a lubrication system promotes.

A. high flow at low pressure.

B. low flow at low pressure.

C. low flow at high pressure.

Ans : low flow at high pressure.

Explanation: NIL.

43. Last chance' filters in a lubrication system are serviced during.

A. line maintenance.

B. routine oil change.

C. engine overhaul.

Ans : engine overhaul.

Explanation: NIL.

44. The identification of a lubrication fluid line is the word 'lubrication'.

A. followed by a caution.

B. followed by squares.

C. followed by circles.

Ans : followed by squares.

Explanation: NIL.



Click Here For : DGCA & EASA Module 15 : Part-11 Engine Fuel Systems Question