The type of powerplant used in any particular aircraft is dependent upon what
factors? - ANSWER The type of powerplant used depends upon the mission of
the aircraft and the aircraft's cruising speed.
What can be said regarding the number of cylinders a reciprocating engine has
about its power production? - ANSWER The more cylinders an engine has, the
more power it is capable of producing.
When designing an aircraft engine, which parameter is most important,
performance or reliability? How is this parameter accounted for in engine
design? - ANSWER Reliability; often the engine has redundant parts.
What is a reciprocating engine? - ANSWER This is an engine that utilizes one
or more pistons to convert pressure into a rotating motion.
What are the three types of engines which were designed and used during
WWI? Briefly describe them. - ANSWER -Rotary-Type Radial: In this engine,
the crankshaft is held stationary and cylinders rotate about the crankshaft
-In-Line: The cylinders are arranged in a single row parallel to the crankshaft
-V-type: The cylinders are arranged on the crankcase in two rows forming the
letter V
List the advantages of the in-line engine. - ANSWER Presents a small frontal
area (low-drag nacelle configuration).
When the cylinders are mounted inverted, better pilot visibility and shorter
landing gear is possible.
List the disadvantages of the in-line engine - ANSWER Low horsepower-to-
weight ratio
Requires either a cooling fluid to remove heat or complicated baffles to route
cooling air (the rear-most cylinders receive little airflow)
, What are the three types of engines which were designed and used after WWI?
Briefly describe them. - ANSWER -Radial Engines: the cylinders are arranged
around the crankshaft but the crankshaft rotates, not the cylinders
-Multiple-Row Radial Engines: the largest and most powerful piston-type
engines ever built and used
-Opposed, Flat or O-type Engines: This is an engine in which the cylinders are
double-ended, with a piston at each end and no cylinder-head
What type of reciprocating engine design provides the best power-to-weight
ratio of all the different types of piston engines? - ANSWER The multiple-row
radial engine has the lowest weight-to-horsepower ratio of all the different types
of piston engines
What does the term "displacement" mean when used in reference to a piston
engine? - ANSWER Displacement is the total volume of air/fuel mixture an
engine can draw in during one complete engine cycle.
In a piston engine, displacement is the volume that is swept as the pistons are
moved from top dead center (TDC) to bottom dead center (BDC)
What is a piston and what is its function? - ANSWER - The piston is a plunger
that moves back and forth or up and down within an engine cylinder barrel
- The piston transmits the force of the burning and expanding gases in the
cylinder through the connecting rod to the engine crankshaft
What is the purpose of a piston ring? - ANSWER These are used to ensure a
tight fit between the cylinder walls and the piston skirt. This is necessary to
prevent loss of gases and to minimize friction (these are not rubber, but cast
iron)
There are two types of piston rings. What are they and what is the difference
between them? - ANSWER Compression rings and oil rings. Oil rings are used
to control the quantity of lubricant supplied to the cylinder walls and to prevent
oil from getting into the combustion chamber.
What is considered the main power section of a reciprocating engine? -
ANSWER The cylinder
factors? - ANSWER The type of powerplant used depends upon the mission of
the aircraft and the aircraft's cruising speed.
What can be said regarding the number of cylinders a reciprocating engine has
about its power production? - ANSWER The more cylinders an engine has, the
more power it is capable of producing.
When designing an aircraft engine, which parameter is most important,
performance or reliability? How is this parameter accounted for in engine
design? - ANSWER Reliability; often the engine has redundant parts.
What is a reciprocating engine? - ANSWER This is an engine that utilizes one
or more pistons to convert pressure into a rotating motion.
What are the three types of engines which were designed and used during
WWI? Briefly describe them. - ANSWER -Rotary-Type Radial: In this engine,
the crankshaft is held stationary and cylinders rotate about the crankshaft
-In-Line: The cylinders are arranged in a single row parallel to the crankshaft
-V-type: The cylinders are arranged on the crankcase in two rows forming the
letter V
List the advantages of the in-line engine. - ANSWER Presents a small frontal
area (low-drag nacelle configuration).
When the cylinders are mounted inverted, better pilot visibility and shorter
landing gear is possible.
List the disadvantages of the in-line engine - ANSWER Low horsepower-to-
weight ratio
Requires either a cooling fluid to remove heat or complicated baffles to route
cooling air (the rear-most cylinders receive little airflow)
, What are the three types of engines which were designed and used after WWI?
Briefly describe them. - ANSWER -Radial Engines: the cylinders are arranged
around the crankshaft but the crankshaft rotates, not the cylinders
-Multiple-Row Radial Engines: the largest and most powerful piston-type
engines ever built and used
-Opposed, Flat or O-type Engines: This is an engine in which the cylinders are
double-ended, with a piston at each end and no cylinder-head
What type of reciprocating engine design provides the best power-to-weight
ratio of all the different types of piston engines? - ANSWER The multiple-row
radial engine has the lowest weight-to-horsepower ratio of all the different types
of piston engines
What does the term "displacement" mean when used in reference to a piston
engine? - ANSWER Displacement is the total volume of air/fuel mixture an
engine can draw in during one complete engine cycle.
In a piston engine, displacement is the volume that is swept as the pistons are
moved from top dead center (TDC) to bottom dead center (BDC)
What is a piston and what is its function? - ANSWER - The piston is a plunger
that moves back and forth or up and down within an engine cylinder barrel
- The piston transmits the force of the burning and expanding gases in the
cylinder through the connecting rod to the engine crankshaft
What is the purpose of a piston ring? - ANSWER These are used to ensure a
tight fit between the cylinder walls and the piston skirt. This is necessary to
prevent loss of gases and to minimize friction (these are not rubber, but cast
iron)
There are two types of piston rings. What are they and what is the difference
between them? - ANSWER Compression rings and oil rings. Oil rings are used
to control the quantity of lubricant supplied to the cylinder walls and to prevent
oil from getting into the combustion chamber.
What is considered the main power section of a reciprocating engine? -
ANSWER The cylinder
