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POWERPLANT ORAL QUESTIONS - ENGINE
FUEL AND FUEL METERING | COMPREHENSIVE
Q&A FOR GUARANTEED SUCCESS 2025
What are the different engine indications used for trimming a turbine engine? -
correct-answer-Either EPR or r.p.m. is used depending on the particular engine
What maintenance adjustments are normally allowed on an installed
hydromechanical fuel control? -correct-answer-Specific gravity for fuel, idle r.p.m.,
and a maximum r.p.m. (or maximum EPR).
What type of pump can vary the amount of fuel discharged regardless of speed? -
correct-answer-A variable displacement pump.
What is used to keep water, sediment, and foreign matter out of the carburetor? -
correct-answer-The main fuel strainer.
What is the purpose of a pressure relief valve in a constant displacement pump? -
correct-answer-It returns excess fuel that is not required by the engine to the inlet
side of the pump.
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What type of engine-driven fuel pump is widely used other than gear or piston
pumps? -correct-answer-A rotary vane type.
What function do fuel boost pumps perform? -correct-answer-They supply
pressurized fuel to the fuel pump, which helps prevent vapor lock and cavitation.
What is a commonly used type of fuel boost pump? -correct-answer-The
centrifugal type.
What causes vapor lock and why is it of concern? -correct-answer-Vapor lock is
caused by insufficient fuel pressure, high fuel temperatures and excessive fuel
turbulence, which may completely block any fuel flow resulting in engine failure.
What function does the engine-driven pump on a turbine engine perform? -
correct-answer-It provides a continuous supply of fuel at the proper pressure
while the engine is running.
POWERPLANT ORAL QUESTIONS - ENGINE
FUEL AND FUEL METERING | COMPREHENSIVE
Q&A FOR GUARANTEED SUCCESS 2025
What are the different engine indications used for trimming a turbine engine? -
correct-answer-Either EPR or r.p.m. is used depending on the particular engine
What maintenance adjustments are normally allowed on an installed
hydromechanical fuel control? -correct-answer-Specific gravity for fuel, idle r.p.m.,
and a maximum r.p.m. (or maximum EPR).
What type of pump can vary the amount of fuel discharged regardless of speed? -
correct-answer-A variable displacement pump.
What is used to keep water, sediment, and foreign matter out of the carburetor? -
correct-answer-The main fuel strainer.
What is the purpose of a pressure relief valve in a constant displacement pump? -
correct-answer-It returns excess fuel that is not required by the engine to the inlet
side of the pump.
, 2|Page
What type of engine-driven fuel pump is widely used other than gear or piston
pumps? -correct-answer-A rotary vane type.
What function do fuel boost pumps perform? -correct-answer-They supply
pressurized fuel to the fuel pump, which helps prevent vapor lock and cavitation.
What is a commonly used type of fuel boost pump? -correct-answer-The
centrifugal type.
What causes vapor lock and why is it of concern? -correct-answer-Vapor lock is
caused by insufficient fuel pressure, high fuel temperatures and excessive fuel
turbulence, which may completely block any fuel flow resulting in engine failure.
What function does the engine-driven pump on a turbine engine perform? -
correct-answer-It provides a continuous supply of fuel at the proper pressure
while the engine is running.
