1. What is the primary function of the crankshaft in a piston engine?
A) Convert reciprocating motion into rotary motion
B) Control the fuel-air mixture
C) Operate the cooling system
Answer: A) Convert reciprocating motion into rotary motion
2. What type of bearings are commonly used for the crankshaft main journals?
A) Ball bearings
B) Plain bearings
C) Roller bearings
Answer: B) Plain bearings
3. What is the purpose of the camshaft in a piston engine?
A) Rotate the propeller
B) Open and close the valves
C) Increase engine power
Answer: B) Open and close the valves
4. Which component ensures proper lubrication in a piston engine?
A) Carburetor
B) Oil pump
C) Magneto
Answer: B) Oil pump
5. What is the purpose of piston rings?
A) Seal the combustion chamber
B) Lubricate the cylinder
C) Reduce the weight of the piston
Answer: A) Seal the combustion chamber
6. Which of the following is NOT a common method of cooling an aircraft piston engine?
A) Air cooling
B) Water cooling
C) Fuel cooling
Answer: C) Fuel cooling
7. What type of ignition system is used in most aircraft piston engines?
A) Battery ignition system
B) Magneto ignition system
C) Distributor ignition system
Answer: B) Magneto ignition system
8. What is the function of the carburetor in a piston engine?
A) Mix air and fuel
B) Compress the air
C) Increase oil pressure
Answer: A) Mix air and fuel
9. What does a supercharger do in a piston engine?
A) Decreases fuel consumption
B) Increases power by compressing intake air
C) Cools the engine
Answer: B) Increases power by compressing intake air
10. What is detonation in a piston engine?
A) Pre-ignition of fuel before the spark
B) Uncontrolled explosion of fuel-air mixture
C) A normal combustion process
Answer: B) Uncontrolled explosion of fuel-air mixture
11. What is the purpose of an intake valve?
A) Allow fuel-air mixture into the cylinder
B) Release exhaust gases
C) Control oil flow
Answer: A) Allow fuel-air mixture into the cylinder
12. What type of propeller system is commonly used with piston engines?
A) Fixed pitch
B) Variable pitch
C) Both A and B
Answer: C) Both A and B
13. What is the purpose of an oil filter in a piston engine?
A) Cool the engine
B) Remove contaminants from the oil
C) Increase fuel efficiency
Answer: B) Remove contaminants from the oil
14. What is the function of the exhaust valve?
A) Allow fresh fuel-air mixture to enter
B) Release burnt gases
C) Control engine speed
Answer: B) Release burnt gases
15. What happens when the fuel-air mixture is too rich?
A) Engine runs hotter
B) Engine may produce black smoke
C) Engine power increases significantly
Answer: B) Engine may produce black smoke
16. What is the purpose of a turbocharger in a piston engine?
A) Increase power by using exhaust gases to compress intake air
B) Reduce fuel consumption
C) Improve engine cooling
Answer: A) Increase power by using exhaust gases to compress intake air
17. What is the compression ratio in a piston engine?
A) Ratio of exhaust to intake volume
B) Ratio of total cylinder volume to combustion chamber volume
C) Ratio of fuel to air
Answer: B) Ratio of total cylinder volume to combustion chamber volume
18. Which component converts reciprocating motion into rotational motion?
A) Piston
B) Crankshaft
C) Camshaft
Answer: B) Crankshaft
19. What is the function of a primer in a piston engine?
A) To start the engine in cold conditions
B) To increase engine RPM
C) To prevent engine overheating
Answer: A) To start the engine in cold conditions
20. What type of fuel is commonly used in aircraft piston engines?
A) Jet A1
B) Avgas 100LL
C) Diesel
Answer: B) Avgas 100LL