M15.16 Flashcards
What speed do turboprop engines operate at?
300 - 450mph
What height can turboprop engines operate at?
20,000ft
How much total power does the turbo prop engine extract?
95%
The core engine is also known as what?
Gas generator or gas producer
What does the core engine do?
Produce high velocity gasses
How is the gas coupled/ free power turbine engines designed?
So there’s no mechanical connection between the gas generator and free power turbine
What are the advantages of a free power turbine engine?
Vibration not directly transmitted
Engine easier to start
Propeller brake
What is the purpose of the propeller brake?
Prevents the propel at from moving when engines shut down
Direct couple turbines are mechanically connected to what?
Compressor and reduction gearbox
Why would you adjust the pitch of the propeller?
For the power requirements of the engine
Why is a integrated propeller control system needed on direct coupled turbines?
Because propeller is driven directly by the engine
On the direct coupled turbine the propeller and engine speed are what?
Kept constant
What sort of environments do turbo prop a/c operate in?
Hostile environments
Why is the viscosity of the oil high on reduction gear?
Because of the heavy loads put on the gears
Turbo prop engines have a higher reduction ratio then what engines?
Piston engines
Disadvantages of spur gear?
Bulked and noisy
Spur gears are only suitable on what?
Piston engines
Helical cut gears do what?
Reduce noise and vibration
What does a high speed gear train consist of?
A high speed pinion
What does a low speed gear train consist of?
Helical gears
What is the 2 stage spur reduction gearbox housed in?
A triple housing
Engine power is dependant on what?
Mass and temp of gas flow
How is the mass of gas flow controlled?
By varying engine speed through a variable pitch propeller
What does the power leaver do in a twin leaver control system?
Gives control for engine power output
What does the prop conditioning leaver do?
Sets the prop rpm and operates engine hp shut off valve
How do over speed safety devices work?
By corening the blade angle or reducing engine power
