TURBOSHAFT Flashcards
What are turboshaft engines primarily used for?
Produce shaft horsepower (shp)
Why are some extra turbine stages added to turboshaft engines?
Extract maximum energy from exhaust gas flow.
Why is the output shaft of turboshaft engines connected to a reduction gearbox?
Engines operate with very high rotational speeds.
What are the 2 arrangements for turboshaft engines?
Direct coupled
Free turbine (more popular)
What is another application of turboshaft engines?
Use of auxiliary power unit (APU)
What do turboshaft engines require?
Relatively high mass airflow
Prone to ingesting FOD
On what principle do the most simple particle separators work?
Centrifugal force.
What is the purpose of drive systems fitted to turbo-shaft engines?
Transfer the power produced within the engine to drive components.
During the event of an auto-rotation, what will the freewheel units do?
Both units will disengage preventing the main rotors from driving the engines.
What will the freewheel units do if both engines are running at the same rpm?
Engage.
If an engine shuts down or looses power, what will the respective freewheel unit do?
Disengage
What kind of joint will ensure shaft alignment between the engine and the main rotor gearbox?
Universal joint (Absorb low amplitude oscillations produced in flight and opposing engine torques)
On helicopter installations, what are hydraulic pumps generally driven by?
Transmission gearbox
Main rotor gearbox or main gearbox, ensure hydraulic power in event of compete engine failure
What utilities can the utility pump provide power to?
Rescue winch
How can helicopters generate electrical power?
- generator mounted to accessory gear box
- generators mounted onto the main rotor gear box
