Questions tagged [turboshaft]
A type of turbine engine that does not (directly) propel an aircraft, but, rather, provides power for other systems.
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questions
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1answer
82 views
Can coaxial rotors be mounted on a piston engine like the Lycoming O-320?
What are the drawbacks of this compared to coaxial configuration with a turboshaft engine?
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3answers
6k views
Why does a turbine helicopter need to spin a tail rotor?
Should not the exhaust of the turbine supply enough byproduct to deflect and maintain yaw with a simple deflector (i.e. rudder/stabs)?
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1answer
7k views
Do the Mt. Everest rescue helicopters have modified engines to operate at high altitudes?
There are so many climbers on Mt. Everest today that there is now a helicopter rescue service there. They operate rescue up to 21,000 + ft. Because this is essentially stationary service it seems that ...
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1answer
766 views
Does a turboshaft's exhaust provide any thrust?
See the below figure. Does the exhaust gas coming out through the nozzle have any force?
If the exhaust gas has force then how is it controlled by the helicopter?
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3answers
358 views
Can a gas turbine be able to switch from torque to thrust?
Can a turbine engine be switched from providing torque (like a helicopter) to the rotor to transfer power to provide exhaust thrust (like a jet plane)?
Related: BV-347 upgrade this way?
3
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0answers
156 views
Is the combustion process in turbofans and turboshafts different?
According to a journal paper, for a Gnome turboshaft engine, fuel-air equivalence ratio decreases as power output increases. However, for a CFM56 turbofan engine, the opposite trend is true, and ...
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3answers
713 views
why are turboprop/turboshaft engines rated only in horsepower and never in ft-lbs of torque like diesel engines or electric motors?
I realize torque and horsepower are essentially the same measurement since horsepower is simply torque over time. But I'm curious as to why diesel engines or electric motors always provide torque ...
3
votes
1answer
363 views
Do Military Turboshaft engines have a distinctly different sound from Civilian ones?
I live in India, and near an airbase so there are a moderate amount of helicopters flying overhead. My friend claims that he can distinguish between a civilian helicopter or a military one based on ...
3
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2answers
384 views
Benefit of a deswirl vane for a turboshaft helicopter engine
I am trying to understand the benefit of deswirl vanes on a turboshaft helicopter engine. For these type of engines, the kinetic energy of the exhaust stream is essentially wasted energy. Also, ...
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1answer
379 views
Where should I find a Pratt & Whitney Canada PT6 operator's manual?
I'm studying the PT6 in detail but the infos I get around the web are sometimes lacking in depth of informations.
I'm pretty much interested in the power curve vs RPM of this engine.
Where should I be ...
2
votes
3answers
386 views
Why is the first turbine in a turboprop (or turboshaft) connected to the compressor?
Typically the first turbine after the combustion chamber drives the compressor as shown in this picture.
(wikimedia.org)
This first turbine spins the fastest and harvests the most energy from the ...
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2answers
6k views
Are there helicopters with vertically mounted turbines?
On the helicopter representation in this answer, the turbine is horizontal, with gear required to drive the vertical-axis propeller.
Are there helicopters where the turbine is vertical and directly ...
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1answer
1k views
Why does it take so much fuel to start a jet engine?
I just watched an Abrams tank documentary and it said something like it takes "1 liter of fuel for every mile but 39 liters for a startup." Is it true of turbine engines in general that they need a ...
