A&P Powerplant Oral and Practical Exam - Practice Questions & Verified Answers
What is the purpose of dynamics dampers on crankshafts? They reduce engine vibration.
What types of bearings are generally found in reciprocating Plain, Ball and Roller bearings.
engines?
Are the connecting rods used in each cylinder of a radial No, radial engines use master and articulating rod assemblies.
engine the same?
Name the different types of piston rings. Oil control, Compression, and Oil Scrapper.
Where should piston rings gaps be installed relative to Compression ring gaps should be staggered to prevent excessive blow-by.
each other, and why?
What could result from incorrectly installed piston rings? Excessive oil consumption.
What purpose do oil control rings serve? They regulate the thickness of the oil film on the cylinder walls.
What is used to help prevent valve surge or floating in an Two or more springs are used on each valve.
aircraft engine?
On engines equipped with hydraulic valve lifters, what Zero.
should the running valve clearance be?
What is the purpose of valve overlap? It allows better volumetric efficiency and lowers cylinder operating temperatures.
When troubleshooting a running engine malfunction, what No combustion in that cylinder.
does a cold cylinder indicate?
Name at least one part of an inspection that should be Inspect the engine mounts, crankcase, and nose section for damage.
made after a propeller strike.
Stuvia 2026-2027
, A&P Powerplant Oral and Practical Exam - Practice Questions & Verified Answers
What is the fuel pressure range on Float-Type 3 to 5 PSI.
carburetors?
What publication is used to check an engine for normal The manufacturer's maintenance manual.
operation?
What should be done to repair a loose stud in an engine Remove the loose stud, inspect the hole, and possibly use an oversize stud or Heli-
crankcase? Coil insert.
What is an indication that a primer is leaking or is open The engine will not idle properly.
during engine operation?
What procedure should be followed when valve blow-by is Perform a cylinder compression test to identify the faulty cylinder.
indicated by a hissing sound?
What factors about the condition of an engine can be The results determine if the valves, piston rings, and pistons are adequately sealing.
learned by studying the results of a compression test?
What is meant when it is said that an engine part is within A part that can be used in an engine without likely causing failure before the next
'serviceable limits'? TBO interval.
When an engine is overhauled, how is its total time The total time must be continued and the time since major overhaul is logged.
affected?
When an engine is rebuilt, how is its operating history It is granted a zero-time status and considered to have no previous operating
affected? history.
Name some of the precautions that should be performed Disconnect the battery, turn off fuel valves, chock the wheels, and install a tail stand
prior to engine replacement. if necessary.
When inspecting a piston, where are cracks most likely to Highly stressed areas, base of piston bosses, and inside at the junction of the bore
be found? and walls.
How is a cylinder barrel inspected for out of roundness? Measure with a cylinder bore gauge or micrometer, taking readings at 90° to each
other.
Is the aircraft electrical system required to power a cylinder No, a thermocouple is used as the electrical source.
head temperature gauge?
Stuvia 2026-2027
, A&P Powerplant Oral and Practical Exam - Practice Questions & Verified Answers
What are the possible indications of an oil pressure A severe drop in oil pressure while oil temperature remains normal and oil supply is
transmitter or indicator malfunction? full.
What are some indications of induction system leakage? Low power and uneven running.
Explain the main difference and advantage of turbofan A turbofan uses a fan to bypass air around the engine core, providing additional
over turbojet engines. thrust without increasing fuel flow.
Name the major components in a gas turbine engine. Air Inlet, Compression Section, Combustion Section, Turbine Section, Exhaust
Section, Gearbox, and Accessory Section.
What determines the amount of airflow through a turbine The forward speed of the aircraft, compressor speed, and air density.
engine?
Name two types of compressors commonly used in turbine Axial and Centrifugal.
engines.
What is a split compressor system? Also called dual or twin spool compressors, connected to the turbine section, one
inside the other.
What prevents the combustion chambers from burning? Cooling air along the inside of the liner.
What is the purpose of interconnect tubes between can- Flame propagation during start.
type combustion chambers?
What are carbon seals used for in turbine engines? They are used as oil seals for the rotor shaft bearings.
What are the different types of combustion chambers used Can, annular, can-annular, and reverse flow annular.
in turbine engines?
What functions do axial flow turbine nozzles perform? They direct the mass airflow to drive the turbine rotor at a specific angle.
How is thermal stress relieved on a turbine disc? By directing bleed air onto the face of the disk or by grooves being cut in the disk.
Stuvia 2026-2027
What is the purpose of dynamics dampers on crankshafts? They reduce engine vibration.
What types of bearings are generally found in reciprocating Plain, Ball and Roller bearings.
engines?
Are the connecting rods used in each cylinder of a radial No, radial engines use master and articulating rod assemblies.
engine the same?
Name the different types of piston rings. Oil control, Compression, and Oil Scrapper.
Where should piston rings gaps be installed relative to Compression ring gaps should be staggered to prevent excessive blow-by.
each other, and why?
What could result from incorrectly installed piston rings? Excessive oil consumption.
What purpose do oil control rings serve? They regulate the thickness of the oil film on the cylinder walls.
What is used to help prevent valve surge or floating in an Two or more springs are used on each valve.
aircraft engine?
On engines equipped with hydraulic valve lifters, what Zero.
should the running valve clearance be?
What is the purpose of valve overlap? It allows better volumetric efficiency and lowers cylinder operating temperatures.
When troubleshooting a running engine malfunction, what No combustion in that cylinder.
does a cold cylinder indicate?
Name at least one part of an inspection that should be Inspect the engine mounts, crankcase, and nose section for damage.
made after a propeller strike.
Stuvia 2026-2027
, A&P Powerplant Oral and Practical Exam - Practice Questions & Verified Answers
What is the fuel pressure range on Float-Type 3 to 5 PSI.
carburetors?
What publication is used to check an engine for normal The manufacturer's maintenance manual.
operation?
What should be done to repair a loose stud in an engine Remove the loose stud, inspect the hole, and possibly use an oversize stud or Heli-
crankcase? Coil insert.
What is an indication that a primer is leaking or is open The engine will not idle properly.
during engine operation?
What procedure should be followed when valve blow-by is Perform a cylinder compression test to identify the faulty cylinder.
indicated by a hissing sound?
What factors about the condition of an engine can be The results determine if the valves, piston rings, and pistons are adequately sealing.
learned by studying the results of a compression test?
What is meant when it is said that an engine part is within A part that can be used in an engine without likely causing failure before the next
'serviceable limits'? TBO interval.
When an engine is overhauled, how is its total time The total time must be continued and the time since major overhaul is logged.
affected?
When an engine is rebuilt, how is its operating history It is granted a zero-time status and considered to have no previous operating
affected? history.
Name some of the precautions that should be performed Disconnect the battery, turn off fuel valves, chock the wheels, and install a tail stand
prior to engine replacement. if necessary.
When inspecting a piston, where are cracks most likely to Highly stressed areas, base of piston bosses, and inside at the junction of the bore
be found? and walls.
How is a cylinder barrel inspected for out of roundness? Measure with a cylinder bore gauge or micrometer, taking readings at 90° to each
other.
Is the aircraft electrical system required to power a cylinder No, a thermocouple is used as the electrical source.
head temperature gauge?
Stuvia 2026-2027
, A&P Powerplant Oral and Practical Exam - Practice Questions & Verified Answers
What are the possible indications of an oil pressure A severe drop in oil pressure while oil temperature remains normal and oil supply is
transmitter or indicator malfunction? full.
What are some indications of induction system leakage? Low power and uneven running.
Explain the main difference and advantage of turbofan A turbofan uses a fan to bypass air around the engine core, providing additional
over turbojet engines. thrust without increasing fuel flow.
Name the major components in a gas turbine engine. Air Inlet, Compression Section, Combustion Section, Turbine Section, Exhaust
Section, Gearbox, and Accessory Section.
What determines the amount of airflow through a turbine The forward speed of the aircraft, compressor speed, and air density.
engine?
Name two types of compressors commonly used in turbine Axial and Centrifugal.
engines.
What is a split compressor system? Also called dual or twin spool compressors, connected to the turbine section, one
inside the other.
What prevents the combustion chambers from burning? Cooling air along the inside of the liner.
What is the purpose of interconnect tubes between can- Flame propagation during start.
type combustion chambers?
What are carbon seals used for in turbine engines? They are used as oil seals for the rotor shaft bearings.
What are the different types of combustion chambers used Can, annular, can-annular, and reverse flow annular.
in turbine engines?
What functions do axial flow turbine nozzles perform? They direct the mass airflow to drive the turbine rotor at a specific angle.
How is thermal stress relieved on a turbine disc? By directing bleed air onto the face of the disk or by grooves being cut in the disk.
Stuvia 2026-2027
