1 | Page
AMS 274 Turbines Final Exam Questions and
Answers
If the anti-ice air valve is open what happens to EGT?
Ans: EGT increases (tachometer and EPR also shift)
How do you calculate EPR?
Ans: Turbine discharge/Compressor inlet pressure
What are the most common type of thermocouples used?
Ans: Chromel/Alumel (CA)
What do the older style APUs have in them?
Ans: Governors
What is the typical gear down ratio for pneumatic starters?
Ans: 25:1
What is the starting sequence for turbine engines?
Ans: Starter --> Ignition --> Fuel
you hear a clicking noise from the pneumatic starter it indicates:
Ans: The pawls re-engaging (normal)
Typical air flow in a pneumatic starter:
Ans: Air flows into the starter --> Stator vanes (designed to choke in
order to prevent overspeed) --> Turbine
What was Whittle famous for?
© 2025 All rights reserved
, 2 | Page
Ans: Invented the jet engine
What are the 4 types of gas turbines and typical aircraft they are
found on:
Ans: 1. Turbojet (supersonic)
2. Turbofan (large commercial)
3. Turboprop (larger GA)
4. Turboshaft (helicopters)
What is the Brayton Cyle?
Ans: thermodynamic cycle that explains how gas turbine engines run
Bernoulli's principle:
Ans: As the velocity of a fluid increases, the pressure exerted by the
fluid decreases (convergent ducts: velocity increases and pressure
decreases/divergent ducts: velocity decreases and pressure increases)
What company produced the first gas turbine engine in the U.S.?
Ans: General Electric
In a split-spool/dual-spool/twin-spool turbine, what drives what?
Ans: The low-speed turbine drives the first compressor
The high speed turbine drives the second compressor
What is typically found in a turboshaft engine?
Ans: A power turbine
What is the low bypass, medium bypass, and high bypass general
engine ratios?
© 2025 All rights reserved
AMS 274 Turbines Final Exam Questions and
Answers
If the anti-ice air valve is open what happens to EGT?
Ans: EGT increases (tachometer and EPR also shift)
How do you calculate EPR?
Ans: Turbine discharge/Compressor inlet pressure
What are the most common type of thermocouples used?
Ans: Chromel/Alumel (CA)
What do the older style APUs have in them?
Ans: Governors
What is the typical gear down ratio for pneumatic starters?
Ans: 25:1
What is the starting sequence for turbine engines?
Ans: Starter --> Ignition --> Fuel
you hear a clicking noise from the pneumatic starter it indicates:
Ans: The pawls re-engaging (normal)
Typical air flow in a pneumatic starter:
Ans: Air flows into the starter --> Stator vanes (designed to choke in
order to prevent overspeed) --> Turbine
What was Whittle famous for?
© 2025 All rights reserved
, 2 | Page
Ans: Invented the jet engine
What are the 4 types of gas turbines and typical aircraft they are
found on:
Ans: 1. Turbojet (supersonic)
2. Turbofan (large commercial)
3. Turboprop (larger GA)
4. Turboshaft (helicopters)
What is the Brayton Cyle?
Ans: thermodynamic cycle that explains how gas turbine engines run
Bernoulli's principle:
Ans: As the velocity of a fluid increases, the pressure exerted by the
fluid decreases (convergent ducts: velocity increases and pressure
decreases/divergent ducts: velocity decreases and pressure increases)
What company produced the first gas turbine engine in the U.S.?
Ans: General Electric
In a split-spool/dual-spool/twin-spool turbine, what drives what?
Ans: The low-speed turbine drives the first compressor
The high speed turbine drives the second compressor
What is typically found in a turboshaft engine?
Ans: A power turbine
What is the low bypass, medium bypass, and high bypass general
engine ratios?
© 2025 All rights reserved