1
Avia 91 Midterm 1 Practice test Questions with Answers
(100% Correct Answers)
Thrust produced has an approximately linear relationship with engine
rpm— Answer: False
Operation in high humidity can dramatically reduce the thrust
produced by a turbine engine— Answer: False
The engine driven fuel pump is designed to deliver the exact amount
of fuel to meet the engine needs— Answer: False
Fuel boost pumps are usually of the positive displacement type—
Answer: False
Which one of these is not a type of combuster?— Answer: Centripetal
What temperature typically limits the thrust output of a gas turbine
engine?— Answer: Turbine Inlet Temperature (TIT) limits the thrust
output of a gas turbine engine
What is TSFC and what are the units of TSFC? i.e., if the TSFC is stated
as 0.7, what does the "0.7" represent?— Answer: Amount of fuel in
pounds required to produce 1 pound of thrust for 1 hour
© 2025 All rights reserved
, 2
What is the purpose of the diffuser section on a gas turbine engine?
Moreover, under what principle does the diffuser operate?— Answer:
The diffuser is a divergent duct that reduces airspeed velocity and
increases static pressure before the air is moved to combustion section.
Manifold distributes smooth air to combustion section
Name three advantages of an axial flow compressor versus a radial
flow compressor— Answer: Greater compression ratio due to multiple
compressors, smaller frontal area of engine, and higher fuel efficiency
What are some disadvantages of an axial flow compressor?— Answer:
Higher cost, high weight, difficult to manufacture
What is the overall result of the compressor section?— Answer:
Increased air pressure and relatively constant air velocity from
compressor inlet to outlet
What are two methods of controlling a compressor stall?— Answer: 1.
Reduce speed, lower angle of attack, and maintain idle RPM.
2. Inlet Guide Vanes and Stator Vanes vary in pitch by allowing
airflow into the compressor
© 2025 All rights reserved
Avia 91 Midterm 1 Practice test Questions with Answers
(100% Correct Answers)
Thrust produced has an approximately linear relationship with engine
rpm— Answer: False
Operation in high humidity can dramatically reduce the thrust
produced by a turbine engine— Answer: False
The engine driven fuel pump is designed to deliver the exact amount
of fuel to meet the engine needs— Answer: False
Fuel boost pumps are usually of the positive displacement type—
Answer: False
Which one of these is not a type of combuster?— Answer: Centripetal
What temperature typically limits the thrust output of a gas turbine
engine?— Answer: Turbine Inlet Temperature (TIT) limits the thrust
output of a gas turbine engine
What is TSFC and what are the units of TSFC? i.e., if the TSFC is stated
as 0.7, what does the "0.7" represent?— Answer: Amount of fuel in
pounds required to produce 1 pound of thrust for 1 hour
© 2025 All rights reserved
, 2
What is the purpose of the diffuser section on a gas turbine engine?
Moreover, under what principle does the diffuser operate?— Answer:
The diffuser is a divergent duct that reduces airspeed velocity and
increases static pressure before the air is moved to combustion section.
Manifold distributes smooth air to combustion section
Name three advantages of an axial flow compressor versus a radial
flow compressor— Answer: Greater compression ratio due to multiple
compressors, smaller frontal area of engine, and higher fuel efficiency
What are some disadvantages of an axial flow compressor?— Answer:
Higher cost, high weight, difficult to manufacture
What is the overall result of the compressor section?— Answer:
Increased air pressure and relatively constant air velocity from
compressor inlet to outlet
What are two methods of controlling a compressor stall?— Answer: 1.
Reduce speed, lower angle of attack, and maintain idle RPM.
2. Inlet Guide Vanes and Stator Vanes vary in pitch by allowing
airflow into the compressor
© 2025 All rights reserved
