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Engine Cooling Systems Questions and
Answers (Expert Solutions)
Q: Excessive heat is always undesirable in both reciprocating and turbine aircraft
engines. If means were not available for its control or elimination, major damage or
_________ would occur, 🗹🗹: Complete engine failure
Q: The vast majority of reciprocating engines are _____ cooled, 🗹🗹: Air
Q: In a liquid-cooled engine, around the cylinder are __________, in which liquid coolant is
circulated and the coolant takes away the excess heat., 🗹🗹: Water Jackets
Q: In a liquid-cooled engine, excess heat is normally dissipated by a ____________ or ________
using air flow, 🗹🗹: Heat Exchanger, Radiator
Q: An internal-combustion engine is a heat machine that converts _________ energy in the
fuel into _______ energy at the crankshaft, 🗹🗹: Chemical, Mechanical
Q: Even the most efficient aircraft engines may waste ____ to ____ percent of the original
energy in the fuel., 🗹🗹: 60, 70
Q: Excessive Heat is undesirable in any internal combustion engine for three principle
reasons:
a_______
b_______
c_______, 🗹🗹: -Affects the behavior of the fuel/air charge
-Weakens and shortens the life of engine parts
-Impairs Lubrication
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Q: If the temperature inside the engine cylinder is too great, the fuel-air mixture is
preheated, and combustion occurs __________ the desired time, 🗹🗹: before
Q: Premature combustion causes ________, _________, and other undesirable conditions,
there must be a way to eliminate heat before it causes damage., 🗹🗹: Detonation,
Knocking
Q: A cylinder on a large engine is roughly the size of a gallon jug. Its outer surface,
however, is _________ by the use of ______________ so that it presents a barrel sized exterior
to the cooling fins, 🗹🗹: Increased, Cooling Fins
Q: If too much of the cooling fin area is broken off, the cylinder cannot cool properly,
and a _________ develops, 🗹🗹: Hotspot
Q: ______ and ______ are designed to force air over the cylinder, 🗹🗹: Cowling, Baffles
Q: The baffles direct the air close around the cylinders and prevent it from forming hot
pools of ________ air while the main streams rush by unused. An engine can have an
operating temperature that is too low. For the same reasons that an engine is warmed
up before takeoff, it is __________ during flight, 🗹🗹: Stagnant, Kept Warm
Q: The most common means of controlling cooling is the use of _______., 🗹🗹: Cowl
Flaps
Q: Cowl flaps are opened and closed by:
a.______
b_______
c_______, 🗹🗹: - Electric Motor-Driven jackscrews
- Hydraulic Actuators
- Manually
Q: When _______ for increased cooling, the cowl flaps produce _____ and sacrifice
streamlining for the added cooling, 🗹🗹: Extended, drag
Engine Cooling Systems Questions and
Answers (Expert Solutions)
Q: Excessive heat is always undesirable in both reciprocating and turbine aircraft
engines. If means were not available for its control or elimination, major damage or
_________ would occur, 🗹🗹: Complete engine failure
Q: The vast majority of reciprocating engines are _____ cooled, 🗹🗹: Air
Q: In a liquid-cooled engine, around the cylinder are __________, in which liquid coolant is
circulated and the coolant takes away the excess heat., 🗹🗹: Water Jackets
Q: In a liquid-cooled engine, excess heat is normally dissipated by a ____________ or ________
using air flow, 🗹🗹: Heat Exchanger, Radiator
Q: An internal-combustion engine is a heat machine that converts _________ energy in the
fuel into _______ energy at the crankshaft, 🗹🗹: Chemical, Mechanical
Q: Even the most efficient aircraft engines may waste ____ to ____ percent of the original
energy in the fuel., 🗹🗹: 60, 70
Q: Excessive Heat is undesirable in any internal combustion engine for three principle
reasons:
a_______
b_______
c_______, 🗹🗹: -Affects the behavior of the fuel/air charge
-Weakens and shortens the life of engine parts
-Impairs Lubrication
, Page | 2
Q: If the temperature inside the engine cylinder is too great, the fuel-air mixture is
preheated, and combustion occurs __________ the desired time, 🗹🗹: before
Q: Premature combustion causes ________, _________, and other undesirable conditions,
there must be a way to eliminate heat before it causes damage., 🗹🗹: Detonation,
Knocking
Q: A cylinder on a large engine is roughly the size of a gallon jug. Its outer surface,
however, is _________ by the use of ______________ so that it presents a barrel sized exterior
to the cooling fins, 🗹🗹: Increased, Cooling Fins
Q: If too much of the cooling fin area is broken off, the cylinder cannot cool properly,
and a _________ develops, 🗹🗹: Hotspot
Q: ______ and ______ are designed to force air over the cylinder, 🗹🗹: Cowling, Baffles
Q: The baffles direct the air close around the cylinders and prevent it from forming hot
pools of ________ air while the main streams rush by unused. An engine can have an
operating temperature that is too low. For the same reasons that an engine is warmed
up before takeoff, it is __________ during flight, 🗹🗹: Stagnant, Kept Warm
Q: The most common means of controlling cooling is the use of _______., 🗹🗹: Cowl
Flaps
Q: Cowl flaps are opened and closed by:
a.______
b_______
c_______, 🗹🗹: - Electric Motor-Driven jackscrews
- Hydraulic Actuators
- Manually
Q: When _______ for increased cooling, the cowl flaps produce _____ and sacrifice
streamlining for the added cooling, 🗹🗹: Extended, drag
