UAV Turbines
 

I came across this article on a 200 hp turboprop in development.
https://www.sae.org/news/2018/03/uav...77&bid=2058339

The company also has 10 hp, 50 hp and 150 hp models
https://www.uavturbines.com/wp-conte...AV-Dossier.pdf

I'm posting this not because I think the company is interested in the homebuilt aircraft market (although they might be), but because I think the technology of using a centrifugal compressor, a radial inflow turbine (basically turbocharger technology) with a thermal recuperator to improve efficiency and thus bsfc is the way forward for small turbines that could be used in homebuilt aircraft. The market for military uavs is pushing the development of heavy fuel/jet A turbines in the 100-200 hp range, we just might benefit from it.

Turbine
 

Terry,

Great concept and exciting for the homebuilt market for sure. BUT- they have a contract with the military so I don't think us homebuilt guys are gonna have the deep pockets the government does. If they come out with a turbine cost comparable to the trusty Lycomings maybe they will have a market.

other turbines?
 

Maaaaaaaaaany moons ago someone developed a turboprop BD-5t, with a little APU from helicopters, I believe it was a Solar.

I see they are still around, with some military uses of course.....this one....
T62T-27 turboshaft - 150 hp (110 kW) @ 61,250 turbine rpm, with 1x 8,000 and 1x 8,216 rpm outputs
...obviously the right gearbox is the thing, as usual......to drive a prop reliably.

could be about the right fit for some RV's?

There is an interesting development in Australia. Small turboprop engine https://www.turb.aero/ta200tp-turboprop looks very promising. Extensive discussion here https://www.recreationalflying.com/t...engine.158904/

Many amateurs are successful at building turboshafts around automotive boosters these days, see here and here for instance. What separates the big boys from these garage efforts is knowing how to run a business. The main hurdle any new GA engine has to overcome is that nobody will touch it for people transport until it has many hours in service. Very few start-ups have the $$$ to survive their way out of the "cool engineering" phase into production. And then they'd have to reckon with Lycoming, who know how to make turbines too!

Myself, I think the game-changer here could be 3D printing of metal recuperators. For example, this company uses a clever trick to print sintered titanium or stainless parts using an inexpensive powder bed process. My copy of Wilson and Korakianitis has dog ears--if there are any bona fide jet designers on this forum what say you we come up with an open source design of a high eff turboprop with off-the-shelf parts? OpenFOAM FTW.

Turbine smooth, really.
 

Terry/Vlad,
The Turbine RV market isn't new.
Many moons ago I was interested in converting my RV4 to Turbine power. Affordable Turbine Power in PA was flying an RV4 package based on the Solar T-64 Turbine widely in use on other applications. They also manufactured an associated gear reduction and fuel control.

https://youtu.be/tsRLFXirq4o
RV4-T

Unfortunately like any other aviation related venture, "to make a small fortune, start with a large one". The company went out of business, quit answering calls in 2004 and the aircraft was sold on BS engine-less.
It would be great to see an affordable Turbine power option for Sport Planes but it hasn't materialized yet. Your link though, shows promise.

I for one think Electric power will be the next big development.
V/R
Smokey

PS: One side note on the RV4-T, it had one of the nicest set of Aluminum Wheel pants and cowling I have seen, ever. English wheel artisanship at it's finest. A gorgeous airplane for sure.:)

And a similar number of moons ago, the Experimental Aircraft community was speculating over low cost jet engines being developed for the early cruise missiles, for example the Tomahawk - in service in the 80's - being available for our homebuilts.

If they were cheap enough it was thought one of two 600 lb thrust units could be used. Unfortunately military grade hardware never really dropped in price.

One that met this idea did go into limited production (7?) was the Caproni jet version of the A21 sailplane with a 200 lb thrust engine.

http://all-aero.com/index.php/contac...9-caproni-a-21

I've flown in a Caproni A21 and it is an impressive, large glider, but it was only the pure sailplane version. :)

In that thrust range there is the Czech engine used for SubSonex, PBS TJ100. Not enough thrust for an RV, and $60k apiece. Perhaps install two of these, and put "INOP" on the fuel burn indicator. :p

The turboprop from the same company based on their TJ100 gasifier is worth watching, but it's not recuperated so the "INOP" joke still applies. :rolleyes:

Velocity Aircraft are building several twin engine aircraft using that turboprop for "an external government." The fuel flow, as you expect, is very high. But, for some applications where light weight and high power are required (mountain ops?) it may fill a niche nicely.

I've been seeing folks hawking "cheap turbines" since the Chrysler Turbine in '62. And, I do truly believe that one day someone will figure out how to make it both cheap and fuel-miserly. Until then, Lycosaurus rules the roost.

Rolls Royce was doing some cost analysis on them---at least that what they told me at OSH, and found that it was not profitable. They had a detuned 450HP that they were playing with, but scraped the idea. Seems to be the same with everyone else too. We have a client with a RV14 with a deposit on a 200hp Turbine, but I havent heard any more about it, or the development in several months. We were going to help develop a FWF package for it, but we'll see.

Tom