1/7/26, 4:43 AM ASA Powerplant Oral Study Guide (All Questions) Most Recent exam COMPLETE (2026) EXAM Questions and Answers (Verified A…
ASA Powerplant Oral Study Guide (All Questions)
Most Recent exam COMPLETE (2026) EXAM
Questions and Answers (Verified Answers) (Latest
Update 2026) UPDATE!!
Save
Terms in this set (259)
What is the main advantage of a The horizontally opposed engine has a much
horizontally opposed engine over a smaller frontal area and is easier to streamline than
radial engine for powering modern a radial engine.
aircraft?
How many throws are there in the Six.
crankshaft of a six-cylinder
horizontally opposed engine?
What kind of connecting rod A master rod connects the single throw of the
arrangement is used in a radial crankshaft with a piston. All of the other pistons are
engine? connected to the master rod with link rods.
Of what material are most piston Gray cast iron.
rings made?
What is the reason for using Hydraulic valve lifters keep all of the clearance out
hydraulic valve lifters in an aircraft of the valve operating mechanism. This decreases
engine? the wear of the valve train components.
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,1/7/26, 4:43 AM ASA Powerplant Oral Study Guide (All Questions) Most Recent exam COMPLETE (2026) EXAM Questions and Answers (Verified A…
At what speed does the camshaft The camshaft turns at one half of the crankshaft
turn, relative to the crankshaft speed speed.
in a horizontally opposed engine?
What kind of main bearings are used Steel-backed, lead-alloy bearing inserts.
in a horizontally opposed engine?
On what stroke is the piston of a On the exhaust stroke.
reciprocating engine when the intake
valve begins to open?
On what stroke is the piston of a On the power stroke.
reciprocating engine when the
exhaust valve begins to open?
Why are both the hot and cold valve The hot clearance is given for valve timing
clearances given for most radial purposes. The timing is adjusted with the valves in
engines? cylinder number one, set with the hot clearance.
When the timing is set, all of the valves are
adjusted to their cold clearance.
What is meant by a cam-ground A piston that is not perfectly round. Its dimension
piston? parallel with the wrist pin is several thousandths of
an inch less than its dimension perpendicular to the
wrist pin. When the piston reaches operating
temperature, the metal in the piston pin boss
expands enough that the piston becomes perfectly
round.
Where is the piston in a reciprocating About 30 degrees of crankshaft rotation before the
engine when the ignition spark piston reaches top center on the compression
occurs? stroke.
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,1/7/26, 4:43 AM ASA Powerplant Oral Study Guide (All Questions) Most Recent exam COMPLETE (2026) EXAM Questions and Answers (Verified A…
What is meant by a full-floating wrist A wrist pin that is not clamped in either the piston
pin? or the connecting rod. Full-floating wrist pins are
kept from scoring the cylinder walls by soft metal
plugs in their ends.
Why do most aircraft reciprocating By using more than one spring and having the wire
engines use more than one spring on diameter and pitch of the springs different, valve
each valve? float is minimized. The springs have different
resonant frequencies, so at least one spring will
always be exerting a force on a valve.
Would excessive valve clearance Excessive valve clearance will cause the valve to
cause the valves to open early or open late and close early.
late?
What is the purpose of valve overlap Valve overlap allows the inertia of the exhaust
in a reciprocating engine? gases leaving the cylinder to help the fresh
induction charge start flowing into the cylinder.
What type of piston rings are Compression rings, oil control rings, and oil wiper
installed on the pistons of an aircraft rings.
reciprocating engine?
Why are some exhaust valves The metallic sodium melts at engine operating
partially filled with metallic sodium? temperature and sloshes back and forth inside the
hollow valve. It picks up heat from the valve head
and transfers it into the valve stem, so it can be
transferred to the cylinder head through the valve
guide.
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, 1/7/26, 4:43 AM ASA Powerplant Oral Study Guide (All Questions) Most Recent exam COMPLETE (2026) EXAM Questions and Answers (Verified A…
What causes detonation in an aircraft Excessive heat and pressure in the engine cylinder
engine? causes the fuel-air mixture to reach its critical
pressure and temperature. Under these conditions,
the mixture explodes rather than burns. This
explosion is called detonation.
Why is a compression check A compression check can determine the condition
important for determining the of the seal between the piston rings and the
condition of an aircraft reciprocating cylinder walls, and the seal between the intake and
engine? exhaust valves and their seats.
What is meant by the compression The ratio of the volume of the cylinder with the
ratio of a reciprocating engine? piston at the bottom of its stroke to the volume
with the piston at the top of its stroke.
What are the two basic sections of a The hot section and the cold section.
turbine engine?
What are the two basic types of Axial-flow and centrifugal.
compressors that are used in aircraft
turbine engines?
What is the purpose of the stators in The stators convert some velocity energy into
an axial-flow compressor? pressure energy and change the direction of the air
so it is proper for the next stage of rotors.
What are three types of combustors Can-type, annular-type, and can-annular type.
used on aircraft turbine engines?
How many igniters are there Two.
normally in an aircraft turbine
engine?
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ASA Powerplant Oral Study Guide (All Questions)
Most Recent exam COMPLETE (2026) EXAM
Questions and Answers (Verified Answers) (Latest
Update 2026) UPDATE!!
Save
Terms in this set (259)
What is the main advantage of a The horizontally opposed engine has a much
horizontally opposed engine over a smaller frontal area and is easier to streamline than
radial engine for powering modern a radial engine.
aircraft?
How many throws are there in the Six.
crankshaft of a six-cylinder
horizontally opposed engine?
What kind of connecting rod A master rod connects the single throw of the
arrangement is used in a radial crankshaft with a piston. All of the other pistons are
engine? connected to the master rod with link rods.
Of what material are most piston Gray cast iron.
rings made?
What is the reason for using Hydraulic valve lifters keep all of the clearance out
hydraulic valve lifters in an aircraft of the valve operating mechanism. This decreases
engine? the wear of the valve train components.
https://quizlet.com/1127857791/asa-powerplant-oral-study-guide-all-questions-most-recent-exam-complete-2026-exam-questions-and-answers-verifi… 1/37
,1/7/26, 4:43 AM ASA Powerplant Oral Study Guide (All Questions) Most Recent exam COMPLETE (2026) EXAM Questions and Answers (Verified A…
At what speed does the camshaft The camshaft turns at one half of the crankshaft
turn, relative to the crankshaft speed speed.
in a horizontally opposed engine?
What kind of main bearings are used Steel-backed, lead-alloy bearing inserts.
in a horizontally opposed engine?
On what stroke is the piston of a On the exhaust stroke.
reciprocating engine when the intake
valve begins to open?
On what stroke is the piston of a On the power stroke.
reciprocating engine when the
exhaust valve begins to open?
Why are both the hot and cold valve The hot clearance is given for valve timing
clearances given for most radial purposes. The timing is adjusted with the valves in
engines? cylinder number one, set with the hot clearance.
When the timing is set, all of the valves are
adjusted to their cold clearance.
What is meant by a cam-ground A piston that is not perfectly round. Its dimension
piston? parallel with the wrist pin is several thousandths of
an inch less than its dimension perpendicular to the
wrist pin. When the piston reaches operating
temperature, the metal in the piston pin boss
expands enough that the piston becomes perfectly
round.
Where is the piston in a reciprocating About 30 degrees of crankshaft rotation before the
engine when the ignition spark piston reaches top center on the compression
occurs? stroke.
https://quizlet.com/1127857791/asa-powerplant-oral-study-guide-all-questions-most-recent-exam-complete-2026-exam-questions-and-answers-verifi… 2/37
,1/7/26, 4:43 AM ASA Powerplant Oral Study Guide (All Questions) Most Recent exam COMPLETE (2026) EXAM Questions and Answers (Verified A…
What is meant by a full-floating wrist A wrist pin that is not clamped in either the piston
pin? or the connecting rod. Full-floating wrist pins are
kept from scoring the cylinder walls by soft metal
plugs in their ends.
Why do most aircraft reciprocating By using more than one spring and having the wire
engines use more than one spring on diameter and pitch of the springs different, valve
each valve? float is minimized. The springs have different
resonant frequencies, so at least one spring will
always be exerting a force on a valve.
Would excessive valve clearance Excessive valve clearance will cause the valve to
cause the valves to open early or open late and close early.
late?
What is the purpose of valve overlap Valve overlap allows the inertia of the exhaust
in a reciprocating engine? gases leaving the cylinder to help the fresh
induction charge start flowing into the cylinder.
What type of piston rings are Compression rings, oil control rings, and oil wiper
installed on the pistons of an aircraft rings.
reciprocating engine?
Why are some exhaust valves The metallic sodium melts at engine operating
partially filled with metallic sodium? temperature and sloshes back and forth inside the
hollow valve. It picks up heat from the valve head
and transfers it into the valve stem, so it can be
transferred to the cylinder head through the valve
guide.
https://quizlet.com/1127857791/asa-powerplant-oral-study-guide-all-questions-most-recent-exam-complete-2026-exam-questions-and-answers-verifi… 3/37
, 1/7/26, 4:43 AM ASA Powerplant Oral Study Guide (All Questions) Most Recent exam COMPLETE (2026) EXAM Questions and Answers (Verified A…
What causes detonation in an aircraft Excessive heat and pressure in the engine cylinder
engine? causes the fuel-air mixture to reach its critical
pressure and temperature. Under these conditions,
the mixture explodes rather than burns. This
explosion is called detonation.
Why is a compression check A compression check can determine the condition
important for determining the of the seal between the piston rings and the
condition of an aircraft reciprocating cylinder walls, and the seal between the intake and
engine? exhaust valves and their seats.
What is meant by the compression The ratio of the volume of the cylinder with the
ratio of a reciprocating engine? piston at the bottom of its stroke to the volume
with the piston at the top of its stroke.
What are the two basic sections of a The hot section and the cold section.
turbine engine?
What are the two basic types of Axial-flow and centrifugal.
compressors that are used in aircraft
turbine engines?
What is the purpose of the stators in The stators convert some velocity energy into
an axial-flow compressor? pressure energy and change the direction of the air
so it is proper for the next stage of rotors.
What are three types of combustors Can-type, annular-type, and can-annular type.
used on aircraft turbine engines?
How many igniters are there Two.
normally in an aircraft turbine
engine?
https://quizlet.com/1127857791/asa-powerplant-oral-study-guide-all-questions-most-recent-exam-complete-2026-exam-questions-and-answers-verifi… 4/37
