ACS Powerplant Systems & Engine Overhaul 1 — Questions and Answers
Question 1: What is the main purpose of the carburetor in an aircraft engine?
- Lubricate engine parts
- Mix air and fuel (Correct answer)
- Increase engine temperature
- Control exhaust gases
Correct answer: Mix air and fuel
The carburetor mixes air and fuel in the correct ratio for combustion.
Question 2: What component cools the cylinders of an air-cooled engine?
- Cooling fins (Correct answer)
- Turbocharger
- Radiator
- Compressor
Correct answer: Cooling fins
Cooling fins attached to the cylinders dissipate heat.
Question 3: What type of oil system is most common in aircraft engines?
- Wet sump
- Dry sump (Correct answer)
- Splash system
- Hydraulic system
Correct answer: Dry sump
Aircraft engines typically use a dry sump oil system to maintain consistent lubrication.
Question 4: During an overhaul, how are engine cylinders typically cleaned?
- High-pressure water jet
- Bead blasting (Correct answer)
- Chemical wash
- Sandpaper
Correct answer: Bead blasting
Cylinders are usually cleaned by bead blasting to remove carbon and debris.
Question 5: Which tool measures cylinder wear in an engine?
- Feeler gauge
- Micrometer
- Cylinder bore gauge (Correct answer)
- Dial indicator
Correct answer: Cylinder bore gauge
A cylinder bore gauge measures wear inside the engine cylinders.
Question 6: What part regulates the speed of a propeller?
- Tachometer
- Governor (Correct answer)
- Throttle
- Mixture control
Correct answer: Governor
A governor adjusts the propeller blade angle to control RPM.
Question 7: What is used to check crankshaft runout?
- Feeler gauge
- Dial indicator (Correct answer)
- Micrometer
- Torque wrench
Correct answer: Dial indicator
A dial indicator measures crankshaft runout during overhaul.
Question 8: What causes detonation in a reciprocating engine?
- Incorrect oil pressure
- Low cylinder head temperature
- Excessive airspeed
- Premature explosion of the fuel/air mixture (Correct answer)
Correct answer: Premature explosion of the fuel/air mixture
Detonation occurs when the fuel/air mixture explodes rather than burns smoothly.
Question 9: Which type of inspection checks for internal engine cracks?
- Dye penetrant inspection
- Ultrasonic inspection
- Magnetic particle inspection (Correct answer)
- Visual inspection
Correct answer: Magnetic particle inspection
Magnetic particle inspection detects surface and subsurface cracks in ferrous materials.
ACS Powerplant Systems & Engine Overhaul 1
What is the main purpose of the carburetor in an aircraft engine?