New Aussie Turboprop engine (200 HP) introduced at Sun 'n Fun

[Garfly]

 

 

 

[Thruster88]

I hope they can achieve success with a 200hp turbine. Others have tried, the Diemech / PBS TP100 actually flew in an RV10 in 2015 but has seemingly disappeared.

 

https://www.kitplanes.com/turbine-powered-rv-10/

 

https://en.wikipedia.org/wiki/Diemech_TP_100

[Garfly]

Yeah, there's an interesting discussion along those lines in the YouTube comments.

[Bruce Tuncks]

It looks great! If the range is not reduced too much and the engine is remotely affordable, I for one would be looking to buy for my Jab 230

 

[Thruster88]

Unfortunately it will cost twice as much as a 200hp lycoming  and use twice as much fuel.

[kgwilson]

Fuel consumption compared with performance has always been the bugbear of all small turbines & I don't think that issue has really been addressed.

[Kenlsa]

Let’s just support one of our forum members.

Ken

[Garfly]

 

 

 

[onetrack]

Producing a new small turboprop engine for light aircraft right about now, is the equivalent of producing a new and improved hot air balloon in 1919, as an alternative to powered flight.

 

Now, if it was a 200HP electric motor with a new lightweight battery propelling it to sustained high speeds, then I think the general aviation audience would then have their eyes properly open, and be all ears.

[pmccarthy]

We will not have the mineral raw materials to build electric aircraft, or cars, in the numbers required. This is a fundamental blockage, not something that can be overcome by more spending. For example, even if exploration and development of copper mines is accelerated to the maximum, we will have a deficit of one million tonnes of raw copper per year for the next twenty years. And other minerals are similar or worse.

[APenNameAndThatA]

On 7/4/2022 at 8:46 PM, onetrack said:

Producing a new small turboprop engine for light aircraft right about now, is the equivalent of producing a new and improved hot air balloon in 1919, as an alternative to powered flight.

 

Now, if it was a 200HP electric motor with a new lightweight battery propelling it to sustained high speeds, then I think the general aviation audience would then have their eyes properly open, and be all ears.

I admire the engineering, but can’t work out why anyone would want one. In a low-inertia aircraft like an LSA, the decrease in safety from the slower throttle response would cause more danger than the increased reliability would provide, IMHO. Disclaimer: I know nothing about turboprop aircraft. 

 

It would make more sense in a C172, but what’s the point in an exotic C172?  

Edited April 8, 2022 by APenNameAndThatA

[Thruster88]

This is an article about the development of the Allison 250 engine in the late 50's. This engine started out with 250hp. New price now about 300k usd. It would be seem to be an ideal candidate for a recuperator since the compressed air passes by the exhaust area in external tubes. Why haven't the engineers done this if it gives 10-20 improvement in fuel efficiency? 

https://verticalmag.com/features/thelittleenginethatdid/

 

[Geoff_H]

On 07/04/2022 at 5:50 PM, kgwilson said:

Fuel consumption compared with performance has always been the bugbear of all small turbines & I don't think that issue has really been addressed.

I worked in Florida on the design of 185MW gas turbine.  The efficiency of a gas turbine depends heavily on the maximum turbine first row of blade temperature. To get high temperatures you need very exotic blade materials, as a rule of thumb the more you pay the better the efficiency. These people are getting better efficiency by using heat from the exhaust to increase the volume of compressed air so not so much fuel is used to get to maximum temperature.  It is used by a company called micro turbines, small medium efficiency turbine manufacturer.

I hope the guys are a great success.

[Geoff_H]

4 hours ago, Thruster88 said:

This is an article about the development of the Allison 250 engine in the late 50's. This engine started out with 250hp. New price now about 300k usd. It would be seem to be an ideal candidate for a recuperator since the compressed air passes by the exhaust area in external tubes. Why haven't the engineers done this if it gives 10-20 improvement in fuel efficiency? 

https://verticalmag.com/features/thelittleenginethatdid/

 

Recupetators weigh!  Stationary engines of larger size don't use them because of pressure losses in exhaust gas, pressure loses affect turbine output.  

[BrendAn]

Turboprop thruster 😁

[facthunter]

I've flown quite a few Turboprops and complex props are usually part of the Package. Starting  is usually the time when you can overheat them, otherwise the engines are multiple times more reliable than  Pistons. and lighter. IF they fail and you can't feather them the drag is high and you have to have good overspeed protection.  Nev

Edited April 9, 2022 by facthunter

[onetrack]

No-one has yet mentioned the big bugbear with turbine engines - their dreadful thirst. If you're going to develop a successful new fossil fuel engine today, it will at least have to have a serious, measurable improvement in fuel economy over a piston engine.

Pumping more air through a simple piston engine is a proven method of developing more power and efficiency - and todays automotive petrol engines are now coming out with twin turbos to extract the important fuel economy and power gains.

 

The new Stellantis GME T6 engine is a 3.0L twin-turbo petrol in-line 6, and it produces up to 425HP. The "standard" Jeep cast-iron block/alloy head 6.4L V8 only produces 470HP, even with variable valve timing.

The GME T6 engine is reportedly going to be offered as an "upgrade" to the 6.4L V8 in the Chrysler automotive products line.

We'll be seeing a lot more smaller piston petrol engines producing more power than superseded engines in the near future.

 

https://moparinsiders.com/our-first-look-at-the-all-new-twin-turbo-3-0-liter-gme-t6-inline-six-engine/

[walrus]

However that type of engine Stellantis T6 is of no use for aviation because of the duty cycle. An aircraft engine operates at greater than, say, 55% power continuously. An automotive engine does not and won't.

 

I can already get 700hp out of a subaru - for a few minutes. There are auto conversions but they are bought for cost considerations and they are heavy.

 

Fuel efficiency is function of compression ratio. Turbines can't match piston engines. however a turbine and airframe system together can produce a cheaper cost of ownership.

 

[kgwilson]

11 hours ago, onetrack said:

No-one has yet mentioned the big bugbear with turbine engines - their dreadful thirst.

That was the first & only thing I mentioned in my first post.

[Geoff_H]

A high quality turbine is more efficient than an aircraft piston engine.  I think that the turbines usually develop so much more power and capable of higher speeds that have an exponential power demand.  The Rolls Royce Trent engine that was powering a generator was around 40% efficiency.  GTs are very dependants upon air density so they somewhat in efficiency, from day to day.

[Geoff_H]

A quality GT will have a compressor discharge pressure circa 250psi.  That is 16:1.  

[Bruce Tuncks]

Is that 40% comparable with the 25% figure for an IC engine? But if this is so, why are turbines such gas guzzlers?

 

[Bruce Tuncks]

PMC, is not copper recyclable? I reckon the same goes for lithium and lead....  battery stuff which seems not to be recycled as it should be.

[Bruce Tuncks]

Last time I bought a new auto start battery, it was more than $100!

I asked the guy, and he said "world price of lead mate".

So I said that my old battery weighed the same, so I reckon I hadn't used any lead. The recycling center offered $2 for the old battery.

[Geoff_H]

4 minutes ago, Bruce Tuncks said:

Is that 40% comparable with the 25% figure for an IC engine? But if this is so, why are turbines such gas guzzlers?

 

They are bigger and power big aircraft demanding large power.  Low temperature inlet turbines will have significantly less efficiency.  

We know of no material that can take the temperature of stoichiometric combustion.  They would simply melt.  So we must cool the gas out of the stoichiometric burners with air that bypasses the burners.  A GT compressor must compress much more air that doesn't contribute to power, just cooling.  This means that the efficiency drops with lower allowed turbine inlet temperature.  High temperature blading is expensive, single crystal, and usually with small holes to the leading edge of the blade to provide a cooling blanket to the blade.  Expensive.