15.17 Flashcards
What’s the difference between turbo shaft and turbo jet
Turbo shaft produces shaft power to drive machinery instead of thrust
What turbine does a turbo shaft you
Free turbine in the exhaust stream
What turbo shaft engine output measured in
Shaft horsepower SHP
Two major assemblies of turbo shaft engine
Gas generator and power section
Parts of gas generator
Compressor
Combustion chamber
Ignitor
Fuel nozzles
1+ turbine stages
Power section parts
Turbine stages
Gear reduction system
Shaft output
Where are turbo shaft engines used in aviation
Helicopters and apus
What is the purpose of a turbo shaft engine drive system
Transfer power produced within the engine to the components it must drive
How is engine output rpm reduced
In a reduction gearbox then to a coupling shaft into the main rotor gearbox for further reduction
What’s the purpose of a output shaft
Allow the engine to drive the main rotor gearbox
What’s the purpose of a universal joint
Make sure drive shaft alignment absorbs low amplitude oscillations
Oppose the engines torque reaction
Why do engines have reduction gearing installed within the engine
So output shaft is at a useable speed which can be reduced further to a rotor speed by the main rotor gearbox
How is drive shaft flexibility provided
Coupling made of stainless-steel discs bolted to the shafts to provide a flexible joint
What must the drive shaft not carry
Tension or compression loads
What do modern couplings show
Gradual and visible deterioration
(Fail safe)
