powerplant wrong sections

Based on the Aviation Mechanic Oral & Practical Exam Guide provided, here is a set of flashcards covering the specific codes you missed on your Powerplant written exam. These flashcards focus on the "Knowledge" questions associated with those specific ACS codes.

Flashcard Set: Powerplant Oral Exam Review

1. Code: AM.III.A.K2 (Reciprocating Engines)

  • Question: In what position should the crankshaft be when a magneto is being timed to the engine?

  • Answer: The piston in cylinder number 1 should be in the correct position for ignition to occur. This is normally about 30° before top center on the compression stroke. 1

2. Code: AM.III.A.K2 (Reciprocating Engines)

  • Question: What is checked on engine runup to determine the operational condition of the engine?

  • Answer: Idling RPM and manifold pressure, engine acceleration, maximum static RPM and manifold pressure, magneto drop, ignition switch safety check, propeller pitch change, propeller feathering, oil pressure, fuel pressure, and fuel flow. 2

3. Code: AM.III.B.K1 (Turbine Engines)

  • Question: How are the four strokes of a reciprocating engine similar to the sections of a turbine engine?

  • Answer: Intake = air inlet section, compression = compressor section, ignition and power = combustion and turbine sections, exhaust = exhaust section. 3

4. Code: AM.III.B.K1 (Turbine Engines)

  • Question: What type of turbojet engine is commonly used in commercial aviation due to lower noise and better fuel consumption?

  • Answer: High-bypass turbofan engines. 4

5. Code: AM.III.B.K4 (Turbine Engines)

  • Question: What is meant by trimming a turbine engine?

  • Answer: Adjusting the fuel control so the engine develops the correct idle and trim speed RPM. 5

6. Code: AM.III.B.K4 (Turbine Engines)

  • Question: What type of equipment should be used to determine that a turbine engine is performing up to the standards specified by the engine manufacturer?

  • Answer: A JetCal analyzer/trimmer has all of the instrumentation and cables to determine the EGT, EPR, and other parameters specified by the engine manufacturer. 6

7. Code: AM.III.D.K1 (Engine Instrument Systems)

  • Question: What are three types of flow-indicating systems used for turbine engines?

  • Answer: Vane-type flow meters, synchronous mass-type flow meters, and electronic motorless mass flow meters. 7

8. Code: AM.III.D.K1 (Engine Instrument Systems)

  • Question: What do mass flow systems measure?

  • Answer: The mass of the flow. This is affected by the density of the fuel which is in turn affected by the fuel temperature. 8

9. Code: AM.III.D.K1 (Engine Instrument Systems)

  • Question: In what units is an electronic motorless mass flow meter system calibrated?

  • Answer: Pounds per hour of fuel flow. 9

10. Code: AM.III.D.K1 (Engine Instrument Systems)

  • Question: What is indicated in a turbine engine if the fuel flow for all conditions is high?

  • Answer: If there are other instrument abnormalities, there are possibly damaged turbine components. 10

11. Code: AM.III.D.K1 (Engine Instrument Systems)

  • Question: Who is authorized to repair a fuel flow indicating system?

  • Answer: The components can be repaired only by an FAA approved repair station certificated for the particular instruments. 11

12. Code: AM.III.D.K1 (Engine Instrument Systems)

  • Question: Where can you find the electrical power requirements for a fuel flow indicating system?

  • Answer: In the aircraft maintenance manual. 12

13. Code: AM.III.D.K1 (Engine Instrument Systems)

  • Question: Where in the fuel system is the fuel flow transmitter located?

  • Answer: Between the fuel control and the fuel nozzles. 13

14. Code: AM.III.F.K2 (Engine Electrical Systems)

  • Question: What is used as the rectifier to produce direct current in a DC alternator?

  • Answer: Six solid-state diodes. 14

15. Code: AM.III.F.K2 (Engine Electrical Systems)

  • Question: Why is it not necessary to flash the field of a DC alternator after if has been overhauled?

  • Answer: An alternator field is excited by battery current and residual voltage is not used to start the alternator producing current. 15

16. Code: AM.III.F.K2 (Engine Electrical Systems)

  • Question: How many electrical phases are in aircraft alternators?

  • Answer: Three. 16

17. Code: AM.III.F.K2 (Engine Electrical Systems)

  • Question: What is the advantage of using AC power over DC power?

  • Answer: AC voltages can be stepped up to higher voltages, which means that current goes down and smaller wires can be used to save weight. The voltage is stepped back down at the point of use. 17

18. Code: AM.III.F.K2 (Engine Electrical Systems)

  • Question: What is the frequency of AC voltage used in aircraft?

  • Answer: 400 Hz. 18

19. Code: AM.III.F.K7 (Engine Electrical Systems)

  • Question: What factors must be considered when determining wire size?

  • Answer:

    a. System voltage

    b. If the circuit has an intermittent or continuous load

    c. Current

    d. Distance in feet of the wire run

    e. The temperature rating of the wire to be used

    f. The ambient temperature of the area where the wire will be installed

    g. The number of wires in the wire bundle

    h. The percentage of time the wire bundle will be loaded

    i. The maximum altitude the wire will see 19

20. Code: AM.III.G.K2 (Engine Lubrication Systems)

  • Question: What are six functions of the oil in an aircraft engine?

  • Answer:

    a. Reduces friction.

    b. Seals and cushions.

    c. Removes heat.

    d. Cleans inside the engine.

    e. Protects against corrosion.

    f. Performs hydraulic action. 20

21. Code: AM.III.G.K2 (Engine Lubrication Systems)

  • Question: What is the purpose of an air-oil separator, or deaerator, in a turbine engine oil tank?

  • Answer: In normal operation, the oil picks up a quantity of air and it is swirled as it enters the deaerator. The swirling action releases the air from the oil, and the air is used to pressurize the oil tank. 21

22. Code: AM.III.G.K2 (Engine Lubrication Systems)

  • Question: How is oil pressure regulated in an aircraft engine?

  • Answer: A pressure-relief valve senses the desired pressure and sends excess oil back into the engine sump. 22

23. Code: AM.III.G.K2 (Engine Lubrication Systems)

  • Question: What is the purpose of the restricted orifice in the line between the oil pressure gauge and the engine?

  • Answer: The restricted fitting helps dampen any pulsations in the oil pressure caused by the pump. 23

24. Code: AM.III.G.K2 (Engine Lubrication Systems)

  • Question: What is a hot-tank lubrication system for a turbojet engine?

  • Answer: A lubrication system in which the oil cooler is in the pressure subsystem and the scavenged oil is not cooled before it is returned to the tank. 24

25. Code: AM.III.G.K2 (Engine Lubrication Systems)

  • Question: What is a cold-tank lubrication system for a turbojet engine?

  • Answer: A lubrication system in which the oil cooler is in the scavenge subsystem, and the scavenged oil is cooled before it is returned to the tank. 25

26. Code: AM.III.H.K2 (Ignition and Starting Systems)

  • Question: What is an all-weather spark plug?

  • Answer: A shielded spark plug that has a recess in the shielding in which a resilient grommet on the ignition lead forms a watertight seal. 26

27. Code: AM.III.H.K2 (Ignition and Starting Systems)

  • Question: What is meant by the reach of a spark plug?

  • Answer: The length of the threads on the spark plug that screw into the cylinder head. 27

28. Code: AM.III.H.K2 (Ignition and Starting Systems)

  • Question: What is the difference between a hot spark plug and a cold spark plug?

  • Answer: A hot spark plug has a long path for the heat to travel between the nose core insulator and the spark plug shell. In a cold spark plug, the heat has a shorter distance to travel, and the spark plug operates cooler than a hot spark plug. 28

29. Code: AM.III.H.K2 (Ignition and Starting Systems)

  • Question: What is the advantage of fine-wire spark plugs over massive electrode spark plugs?

  • Answer: Fine-wire spark plugs have a firing end that is more open than that of a massive electrode spark plug. The open firing end allows the gases that contain lead to be purged from the spark plug so they will not form solid lead contaminates. 29

30. Code: AM.III.H.K2 (Ignition and Starting Systems)

  • Question: Why is it important that the spark plugs be kept in numbered holes in a tray when they are removed from an engine?

  • Answer: Spark plugs tell a good deal about the internal condition of the cylinders from which they were taken. By knowing the cylinder from which each spark plug came, the mechanic can take the proper action when a spark plug indicates such conditions as detonation or overheating. 30

31. Code: AM.III.H.K2 (Ignition and Starting Systems)

  • Question: Why is it important that a torque wrench always be used when installing spark plugs in an aircraft engine?

  • Answer: If the spark plugs are not put in tight enough, there is the possibility of a poor seal; if they are put in too tight, there is danger of cracking the insulation or damaging the threads on the spark plug or the cylinder. 31

32. Code: AM.III.H.K2 (Ignition and Starting Systems)

  • Question: What kind of gauge should be used to measure the electrode gap in aircraft spark plugs?

  • Answer: A round wire gauge. 32

33. Code: AM.III.H.K7 (Ignition and Starting Systems)

  • Question: What kind of electric starting system is used on many of the smaller turbine engines?

  • Answer: A starter-generator. 33

34. Code: AM.III.H.K7 (Ignition and Starting Systems)

  • Question: Why are air-turbine starters superior to electric starters for large turbine engines?

  • Answer: They are light weight for the torque they produce. 34

35. Code: AM.III.H.K7 (Ignition and Starting Systems)

  • Question: Where does an air-turbine starter get its air for starting the engines on a jet transport airplane?

  • Answer: From an APU, GPU, or from a running engine. 35

36. Code: AM.III.H.K7 (Ignition and Starting Systems)

  • Question: What prevents too high an air pressure from overspeeding an air-turbine starter?

  • Answer: The air shutoff and regulating valve. 36

37. Code: AM.III.H.K7 (Ignition and Starting Systems)

  • Question: Where does an air-turbine starter get its lubricating oil?

  • Answer: It has a self-contained lubrication system with the oil held in the starter housing. 37

38. Code: AM.III.H.K7 (Ignition and Starting Systems)

  • Question: What device in an air-turbine starter warns an aviation mechanic if there are any metal chips or particles in the oil?

  • Answer: Magnetic chip detectors warn of any metal contamination in the oil. 38

39. Code: AM.III.K.K8 (Turbine Engine Air Systems)

  • Question: How is ice prevented from forming on the nose cowl, nose dome, and inlet guide vanes of a turbine engine?

  • Answer: Hot compressor bleed air flows through passages in these components to elevate the surface temperatures sufficiently to prevent ice from forming. 39

40. Code: AM.III.L.K3 (Engine Exhaust and Reverser Systems)

  • Question: What is the purpose of an augmentor on a reciprocating engine exhaust system?

  • Answer: The augmentors are designed to produce a venturi effect to draw an increased airflow over the engine to augment engine cooling. 40

41. Code: AM.III.L.K3 (Engine Exhaust and Reverser Systems)

  • Question: How does a reciprocating engine muffler decrease engine noise?

  • Answer: Exhaust gases from the cylinders are combined into a common manifold that contains a section of the exhaust where the volume increases (expansion chamber), slowing the gases down, diffusing the flow through internal baffles, and reducing the noise. 41

42. Code: AM.III.L.K3 (Engine Exhaust and Reverser Systems)

  • Question: What is a jet aircraft hush kit?

  • Answer: A hush kit is an aerodynamic device that defuses the flow of exhaust from older turbojet engines, by reducing the noise caused by high-velocity jet exhaust. 42

43. Code: AM.III.M.K4 (Propellers)

  • Question: What does the pilot do to change the RPM of an engine equipped with a constant-speed propeller when it is operating within the constant-speed range?

  • Answer: The pilot moves the propeller pitch control. This changes the compression on the speeder spring inside the governor which moves the pilot valve. The pilot valve directs oil into or out of the propeller to change the pitch of the blades. The change in pitch changes the air load on the propeller which changes the RPM. 43

44. Code: AM.III.M.K4 (Propellers)

  • Question: What is the difference between a controllable propeller and a constant-speed propeller?

  • Answer: Basically, it is the control system. A controllable-pitch propeller uses a manually operated oil valve to control the pitch, and a constant-speed propeller uses a governor to control the valve. 44

45. Code: AM.III.M.K4 (Propellers)

  • Question: When making a magneto check on an engine equipped with a constant-speed propeller, should the propeller control be in the low-pitch or the high-pitch position?

  • Answer: It should be in the low-pitch, high RPM position. 45

46. Code: AM.III.M.K6 (Propellers)

  • Question: Where do you find a list of the lubricants that are approved for use in a constant speed propeller?

  • Answer: In the maintenance manual for the propeller. 46

47. Code: AM.III.M.K6 (Propellers)

  • Question: What is the extent of the repairs a mechanic with a Powerplant rating can make to a propeller?

  • Answer: Only minor repairs or minor alterations. 47

48. Code: AM.III.M.K6 (Propellers)

  • Question: Where can examples of acceptable repairs to aluminum alloy propeller blades be found?

  • Answer: In AC 43.13-1B, Chapter 8, Section 4, and in the propeller manufacturer’s service manuals. 48

49. Code: AM.III.M.K6 (Propellers)

  • Question: Is it permissible to cold straighten a damaged aluminum alloy propeller blade to facilitate shipping it to a repair station?

  • Answer: No, this could cause hidden damage that may render the blade nonrepairable. 49

50. Code: AM.III.M.K6 (Propellers)

  • Question: What would be the classification of maintenance for shortening a propeller blade?

  • Answer: Major repair. 50

51. Code: AM.III.M.K6 (Propellers)

  • Question: May transverse cracks in a metal propeller blade be repaired?

  • Answer: No, a transverse crack of any size is reason for rejecting the blade. 51

52. Code: AM.III.M.K6 (Propellers)

  • Question: What damage to an aluminum alloy propeller blade can be repaired by a mechanic holding a Powerplant rating?

  • Answer: Small roughness, nicks, and scratches in the leading edge of the blades. 52

53. Code: AM.III.M.K6 (Propellers)

  • Question: How are small nicks removed from the leading edge of a propeller blade?

  • Answer: File them out with a fine file or stone, leaving a smooth contour. 53

54. Code: AM.III.M.K6 (Propellers)

  • Question: How can you determine that a surface scratch in an aluminum alloy propeller blade is not actually a crack?

  • Answer: Clean the damage out to a saucer-shaped depression and spray the area with a dye penetrant liquid. Allow it time to seep into a crack if one is present, then wipe all of the liquid off the surface. Spray the area with a developer. If the damage is actually a crack, the developer will pull the penetrant out and it will form a visible line. 54

55. Code: AM.III.M.K6 (Propellers)

  • Question: Who, or what facility, is authorized to perform major repairs to a propeller?

  • Answer: An FAA-approved propeller repair station that is authorized for the specific propeller. 55

56. Code: AM.III.M.K6 (Propellers)

  • Question: What checks and maintenance is a mechanic with a Powerplant rating allowed to make on a propeller?

  • Answer:

    • Check the track of the propeller blades.

    • Remove small nicks and scratches from the blades.

    • Check the dynamic balance of a propeller.

    • Lubricate the propeller. 56

57. Code: AM.III.M.K6 (Propellers)

  • Question: What adjustment can a mechanic with a Powerplant rating make to a propeller governor?

  • Answer: Adjust the maximum RPM stop. 57

58. Code: AM.III.M.K6 (Propellers)

  • Question: What instrument is used to measure the blade angle of a propeller?

  • Answer: A universal propeller protractor. 58

59. Code: AM.III.M.K6 (Propellers)

  • Question: Where is the propeller protractor placed to measure the propeller blade angle?

  • Answer: At a distance from the center of the propeller hub. This distance is specified in the propeller maintenance manual in terms of propeller blade stations. 59

60. Code: AM.III.M.K7 (Propellers)

  • Question: What are the basic steps for removing a typical propeller?

  • Answer:

    1. Remove the spinner and remove safety wire from the mounting bolts.

    2. Support the propeller with a sling and mark the alignment between the propeller hub and the engine flange with a felt-tipped pen.

    3. Unscrew the mounting nuts and protect the threads of the mounting studs or bolts as the propeller is removed.

    4. Place the propeller on a cart for transport. 60

61. Code: AM.III.M.K7 (Propellers)

  • Question: What alignment method is used to align a propeller to the engine in a position that reduces operating vibrations?

  • Answer: Special studs or dowel pins align the propeller to the engine in the proper orientation. 61