Garrett JFS 100-13A Turboshaft engine in homebuilt aircraft?

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bmcj

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Wait. That's an APU. Are you sure you want to put your life on an APU?
Oft times, the difference between a propulsion engine and an APU engine is only the way it is housed and used. The core may be identical. That said, I cannot say if that is the case for this particular engine/APU. Someone with specific knowledge of this engine will have to answer that.
 

TFF

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All the baby turbine helicopters run on APU engines; they are much safer than the small piston versions. A small turbine is cool, but 12 gallons an hour cruse is not too good for 100 hp when a 0-200 is 5 gal an hour. 12 gal an hour cruse is 200-250 hp certified engine.
 

Aviator168

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Oft times, the difference between a propulsion engine and an APU engine is only the way it is housed and used. The core may be identical. That said, I cannot say if that is the case for this particular engine/APU. Someone with specific knowledge of this engine will have to answer that.
The parts inside an APU is only guaranteed to run at one speed - WOT.
Turbine pros and cons in Homebuilts
 

DefiantSix

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Oft times, the difference between a propulsion engine and an APU engine is only the way it is housed and used. The core may be identical. That said, I cannot say if that is the case for this particular engine/APU. Someone with specific knowledge of this engine will have to answer that.
Reading the article I linked to carefully, it says that the power plant in question isn't an APU - intended for use on the ground, primarily - but a STARTER. The difference is that the JFS-100 was tested at altitudes up to 30,000 feet. The article also describes the choice of the CH-701 as the testbed vehicle for the engine was something of a safety measure, and not intended to be a demonstration of the "best use" application of the engine.

All in all, it sounds as if Scott Enhi is feeling his way through the applicability of the technology as much as the rest of us.
 

TFF

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APUs and Starter/GPUs are generally the same engine units. One mounts in an airplane and one mounts on a cart. We had one GPU/Starter at the airline that had big compressor stalls as it started. Always the new guy got that one to watch him jump.
 

fredoyster

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Reading the article I linked to carefully, it says that the power plant in question isn't an APU - intended for use on the ground, primarily - but a STARTER. The difference is that the JFS-100 was tested at altitudes up to 30,000 feet. The article also describes the choice of the CH-701 as the testbed vehicle for the engine was something of a safety measure, and not intended to be a demonstration of the "best use" application of the engine.

All in all, it sounds as if Scott Enhi is feeling his way through the applicability of the technology as much as the rest of us.
I have had a lot of good talks with Scott. He said that if he couldn't talk me out of doing one of these turbines in a CH750 that he'd help me any way he could. He is both an impeccable craftsman and a gentleman, but he did talk me out of it. The level of analysis and workmanship needed to do this sort of thing successfully is extremely rare in experimental aviation these days, and Scott is up to the task. I'm not, and I doubt that most of us are. But, talk with him and see for yourself.
 

TFF

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These things throttle, but jet engines do not throttle like a piston. You throttle the governor, but the governor is in control. Constant speed is a must because all jets have narrow powerbands. Turboprops really throttle by changing blade pitch and the gov keeps RPM constant.
 

henryk

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All the baby turbine helicopters run on APU engines; they are much safer than the small piston versions. A small turbine is cool, but 12 gallons an hour cruse is not too good for 100 hp when a 0-200 is 5 gal an hour. 12 gal an hour cruse is 200-250 hp certified engine.
Silnik turbinowy z detonacyjn± komora spalania

-DTR-350 with rotating detonation chamber...circa 10% moore economic.
 
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