Module -16 Final Practice Exam (Piston Engine 72 Questions 90 Mints)

Module -16 (Piston Engine)

Final Practice Exam Test

  

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1. What is the purpose of the float chamber in a carburetor?
   1.   To maintain a constant fuel level for proper mixture
   2.   To cool the fuel
   3.   To regulate air intake
2. In a four-stroke engine, during which stroke does the intake valve open?
   1.   Intake
   2.   Compression
   3.   Power
3. What does a manifold absolute pressure (MAP) gauge measure?
   1.   The fuel pressure
   2.   The oil pressure
   3.   The pressure in the intake manifold
4. A high oil consumption rate in an engine is most likely due to ?
   1.   A lean fuel setting
   2.   Excess fuel in the mixture
   3.   Worn piston rings or valve guides
5. The expansion ratio of an engine is the ratio between ?
   1.   The volume before and after combustion
   2.   The oil pressure before and after circulation
   3.   The air pressure inside the intake manifold
6. The function of piston rings includes?
   1.   Increasing engine RPM
   2.   Regulating oil pressure
   3.   Sealing the combustion chamber
7. Which type of lubrication system is commonly used in aircraft piston engines?
   
   1.   Two-stroke oil injection
   2.   Gravity-fed lubrication
   3.   Wet sump and dry sump
8. The best mixture setting for takeoff is ?
   1.   Full lean
   2.   Full rich
   3.   70% power
9. What is the primary function of an engine governor?
   1.   To regulate fuel flow
   2.   To control RPM automatically
   3.   To prevent overheating
10. A rich air-fuel mixture means?
    
    1.   Equal amounts of air and fuel
    2.   Excess air compared to fuel
    3.   Excess fuel compared to air
11. What does the term "dead center" refer to in a piston engine?
    1.   The moment fuel ignites
    2.   The position where the piston is at its highest or lowest point
    3.   The maximum fuel pressure point
12. A lean mixture is generally used during ?
    1.   Cruise flight
    2.   Takeoff
    3.   Engine start
13. The purpose of valve springs in an engine is to?
    1.   Keep valves closed when necessary
    2.   Increase engine power
    3.   Maintain pressure in the cylinder
14. What is the primary purpose of an impulse coupling in a magneto?
    1.   To advance the spark timing
    2.   To prevent detonation
    3.   To retard ignition timing for starting
15. If an aircraft piston engine experiences detonation, what corrective action should be taken?
    1.   Reduce oil pressure
    2.   Increase throttle and lean the mixture
    3.   Reduce manifold pressure and enrich the mixture
16. The main advantage of using an opposed-type engine in aircraft is?
    1.   It provides a more compact and balanced design
    2.   It increases engine weight
    3.   It is easier to manufacture
17. The purpose of a piston pin is to?
    1.   Secure the piston to the connecting rod
    2.   Maintain valve timing
    3.   Control oil pressure
18. What is the function of the camshaft in a piston engine?
    1.   To maintain fuel pressure
    2.   To increase power output
    3.   To control the opening and closing of the valves
19. Which component controls the ignition timing in a piston engine?
    1.   Carburetor
    2.   Magneto
    3.   Oil pump
20. The stroke of an engine refers to?
    1.   The rotation of the crankshaft
    2.   The duration of the combustion process
    3.   The distance a piston travels from top dead center (TDC) to bottom dead center (BDC)
21. What is the function of an oil control ring in a piston?
    1.   To prevent excessive oil consumption
    2.   To maintain high compression
    3.   To increase fuel efficiency
22. The purpose of a crankshaft counterweight is to?
    1.   Balance the crankshaft and reduce vibration
    2.   Increase power output
    3.   Lubricate the crankshaft
23. The function of an oil cooler is to ?
    
    1.   Increase fuel pressure
    2.   Reduce fuel temperature
    3.   Maintain optimum oil temperature
24. A turbocharger increases engine power by ?
    1.   Reducing engine temperature
    2.   Compressing intake air before it enters the cylinders
    3.   Increasing fuel flow
25. What is the purpose of valve overlap in a four-stroke engine?
    1.   To reduce fuel consumption
    2.   To improve volumetric efficiency
    3.   To control exhaust emissions
26. If the fuel-air mixture is too lean, what is a possible consequence?
    1.   Increased engine power
    2.   Reduced fuel consumption
    3.   Engine overheating and possible detonation
27. The international marking for a fire protection pipe line is a series of ?
    1.   circles
    2.   squares
    3.   diamonds
28. The compression ratio of an aircraft piston engine typically ranges between?
    
    1.   6:1 and 9:1
    2.   2:1 and 4:1
    3.   12:1 and 15:1
29. The function of the throttle valve in a carburetor is to?
    1.   Regulate airflow and engine power
    2.   Increase fuel flow
    3.   Control engine temperature
30. What is a main purpose of a choke in a carburetor?
    1.   To increase air intake
    2.   To reduce fuel consumption
    3.   To enrich the fuel mixture for cold starts
31. How does a piston engine convert heat energy into mechanical energy?
    1.   By compressing fuel vapor for ignition
    2.   By burning fuel to create pressure that moves the pistons
    3.   By heating oil to lubricate moving parts
32. The function of a fuel strainer is to?
    1.   Enrich the fuel mixture
    2.   Increase fuel pressure
    3.   Remove water and debris from the fuel
33. A dry sump lubrication system is used to ?
    1.   Increase oil pressure
    2.   Store oil in a separate tank
    3.   Prevent engine overheating
34. The power output of an engine is measured in?
    1.   Torque
    2.   Horsepower
    3.   Pounds per square inch
35. An excessive lean mixture can cause?
    1.   Increased fuel consumption
    2.   Increased power output
    3.   Engine overheating and knocking
36. What is one disadvantage of a radial engine?
    1.   Reduced engine efficiency
    2.   Increased vibration
    3.   Difficult cooling
37. If an engine is running rough at idle but smooths out at higher RPM, what could be the cause??
    1.   A worn-out crankshaft
    2.   Fouled spark plugs
    3.   A clogged fuel filter
38. What is the purpose of the oil sump?
    1.   To mix oil with fuel
    2.   To store and supply oil to the engine
    3.   To cool engine cylinders
39. Which component transfers motion from the camshaft to the valves?
    1.   Pushrods and rocker arms
    2.   Connecting rod
    3.   Crankshaft
40. Which fuel type is commonly used in aircraft piston engines?
    1.   Diesel
    2.   AVGAS
    3.   Kerosene
41. If an engine experiences pre-ignition, what is likely the cause?
    1.   High oil temperature
    2.   Low fuel pressure
    3.   Excessive carbon deposits
42. What is the function of the spark plug in a piston engine?
    1.   To generate electricity
    2.   To ignite the air-fuel mixture
    3.   To control valve timing
43. A weak valve spring can cause?
    1.   Loss of compression and engine misfire
    2.   Increased fuel efficiency
    3.   Higher oil pressure
44. The valve timing in a four-stroke engine is controlled by ?
    1.   The ignition system
    2.   The crankshaft
    3.   The camshaft
45. If an engine is running at a high altitude, the fuel-air mixture should be?
    1.   Enriched
    2.   Leaned
    3.   Kept constant
46. In a horizontally opposed piston engine, the cylinders are arranged ?
    1.   In a V-shape
    2.   On opposite sides of the crankshaft
    3.   In a single row
47. In a direct-drive engine, the propeller is connected to ?
    1.   The crankshaft
    2.   The camshaft
    3.   The accessory gearbox
48. The function of a carburetor is to?
    1.   Mix fuel and air in the correct ratio
    2.   Control engine timing
    3.   Regulate oil flow
49. The camshaft is driven byThe camshaft is driven by?
    1.   The starter motor
    2.   The magneto
    3.   The crankshaft
50. What is the function of a crankcase breather?
    1.   To regulate fuel flow
    2.   To remove excess air-fuel mixture
    3.   To release pressure and prevent oil leaks
51. Which factor determines the octane rating of aviation fuel?
    1.   Its boiling point
    2.   Its resistance to detonation
    3.   Its weight
52. The four strokes of a piston engine occur in the following order ?
    1.   Intake, Power, Exhaust, Compression
    2.   Intake, Compression, Power, Exhaust
    3.   Compression, Intake, Exhaust, Power
53. Which of the following is a symptom of valve clearance being too tight?
    1.   Poor compression and valve damage
    2.   High oil pressure
    3.   Increased fuel efficiency
54. If a piston engine’s oil pressure is too low, it may indicate ?
    1.   Higher power output
    2.   Better fuel economy
    3.   Oil pump failure or excessive wear
55. An excessive valve clearance will cause?
    1.   Increased valve noise and poor performance
    2.   Engine overheating
    3.   Higher oil pressure
56. Which material is commonly used for aircraft piston engine cylinders?
    1.   Steel alloy
    2.   Nickel alloy
    3.   Aluminum alloy
57. If a piston ring breaks, what is a likely symptom?
    1.   Increased oil consumption and loss of compression
    2.   Higher fuel pressure
    3.   Reduced spark plug wear
58. The function of a tappet (lifter) in an engine is to?
    1.   Regulate oil pressure
    2.   Control air-fuel mixture
    3.   Transfer camshaft motion to the valves
59. The ignition timing in a piston engine is based on?
    1.   Fuel pressure
    2.   Manifold pressure
    3.   Crankshaft position
60. The main function of an engine baffling system is to?
    1.   Improve engine lubrication
    2.   Increase exhaust pressure
    3.   Direct cooling airflow over the cylinders
61. What is detonation in a piston engine?
    1.   The sudden and uncontrolled explosion of fuel in the cylinder
    2.   The premature burning of fuel before the spark plug fires
    3.   The normal combustion process
62. How is an engine’s power output increased?
    1.   Increasing fuel density
    2.   Increasing engine RPM and fuel-air mixture
    3.   Decreasing compression ratio
63. Which component maintains engine timing and synchronization?
    1.   The ignition switch
    2.   The crankshaft and camshaft
    3.   The magneto
64. What is the purpose of a magneto in a piston engine?
    
    1.   To regulate fuel flow
    2.   To generate electrical power for the aircraft
    3.   To provide high-voltage current for spark plugs
65. The term "bottom dead center" (BDC) refers to?
    1.   The highest point in the compression stroke
    2.   The moment the fuel ignites
    3.   The lowest position of the piston in the cylinder
66. TThe clearance volume in a cylinder is the volume?
    1.   Above the piston at bottom dead center
    2.   Between the cylinder head and piston at top dead center
    3.   Displaced by the piston during one revolution
67. The term "stoichiometric ratio" refers to?
    1.   The highest power-producing fuel mixture
    2.   The ideal fuel-to-air mixture for complete combustion
    3.   The lowest fuel consumption ratio
68. What is the effect of a clogged fuel injector in a fuel-injected engine?
    1.   Increase in fuel flow
    2.   Rough engine operation and power loss
    3.   Higher oil temperature
69. The function of a crankshaft is to?
    
    1.   Maintain the correct air-fuel ratio
    2.   Open and close the engine valves
    3.   Convert reciprocating motion into rotary motion
70. What is the primary function of a piston in an internal combustion engine?
    
    1.   To regulate the intake and exhaust valves
    2.   To convert heat energy into mechanical motion
    3.   To control the fuel-air mixture
71. What can cause engine knocking (detonation)?
    1.   Running a rich mixture
    2.   Increasing oil viscosity
    3.   Using a lower-than-required octane fuel
72. If the ignition timing is too advanced, what symptom may occur?
    1.   Engine knocking (detonation)
    2.   Lower cylinder head temperature
    3.   Increased manifold pressure