M15.17 Turboshaft Engines Flashcards
As well as jet thrust what is a Turboshaft engine optimised to produce?
Shaft power
How can the output shaft of a Turboshaft be arranged?
Can be directly coupled to engine turbine or shaft can be driven by a turbine of its own
A turboshafts engine output is measured in what?
Shaft horsepower (SHP)
Two major assemblies of Turboshaft engines?
Gas generator
Power section
The gas generator assembly in a Turboshaft consists of what?
A compressor
Combustion chambers (with igniters and fuel nozzles)
One or more stages of the turbine
The power section of a Turboshaft engine consists of what?
Additional stages of turbines
Gear reduction system
Shaft output
Turboshafts are commonly used in what applications?
Helicopters
APU
How is reduction performed in Turboshaft engines?
The reduction of rpm is done at the rear of the engine where power turbine drives the reduction gearbox. In turn drives the transmission shaft that connects to main gearbox
Drive systems are fitted to Turboshaft for what reason?
To transfer the power produced by engine to the components it drives such as an electrical generator on an APU
What does an output shaft do?
Universal joint is fitted to it
Ensures the drive shaft alignment between the engine and main rotor gearbox
Absorbs low amplitude oscillations produced in flight
Opposes engines torque reaction allowing only the transmission of the engines drive torque
3 switch modes on medium to large helicopters utilising FADEC engines?
Off- Sends final to engine to shut down
Idle- When selected, the engine runs at idle speed
Flight- when selected, engine runs at full speed. Power requirements managed by FADEC
Can the output shaft be coupled directly to the engine turbine?
Yes
What is the Turboshaft engines output measured in?
Horsepower
Why does the output drive of a Turboshaft engine require some for of reduction gearing?
Because the gas turbine engine rotates at extremely high speeds
