Surprise?
Thanks for the kind word of welcome.
I'm surprised, sort of by all the negative stuff in here.
I'm not posting here to defend innodyne and their business practices.
I'm posting here because I like turbines better than recips. They are more reliable. They give better power to weight performance, and perform better at higher altitudes than non super/tubro charged recips.
But for the reasons I've posted In my first post I'm not convienced a Van's is an ideal application for one, nor will innodyne beable to develope one, but I'd like to be convinced.
Tom we are just trying to protect you, and frankly its just honest unvarnished opinions, based on facts. There are a lot of very technical folks here as well as jet jockeys. One cold truth is the economics of owning a small turbine GA plane for personal pleasure flying 100 or 150 hours a year, it's just not practical.
You are flying T-6 Texan II with a real turbine, right, with Pratt & Whitney PT6A-68 turboprop, 1,100 shp (820 kW). Yea I would want a PT6 as well, but comparing the Innodyn to a PT6 is like comparing a kids toy matchbox car to a real Formula race car. One is pushed by a little boys dream and the other is real.
(its a joke and a pretty good one may I say..)
A real Turbine PT6, with prop and all the controllers would cost what...... 1/4 to 1/3 million dollars, just the engine/prop, used? Not many little GA planes can handle 1000 hp. If you want turbine than the best bet right now is Lancair's IVP with a PT6 clone from eastern europe. Apparently you can buy the engines out of old commuter planes, used for $100,000-$150,000. You are looking for about $500,000 to $750,000 to finish a Turbine Lancair IV-Pressurized. Instead of 9 gal/hr for a Lycoming you are looking at 30-40 gal/hr (245 lbs/hr) burn, double for take off? So $200/hr for gas. I'm just not that rich. A RV-10 just can't handle more than approx 260hp, Vne/Mmo wise. What altitude does a T-6 Texan II fly at for X-C, FL250? All RV's are unpressurized and not approved to fly in ice. Are you going to suck O2 from a mask?
Piston engines ROCK in the under 300-350HP range! If you start to need 600-750HP, turbines start to look more attractive, especially if you fly them 2,500 hours a year and are making money with them. Turbines are more reliable. Turbine maintence can be scheduled more accurately, no doubt. Most GA guys fly X-C in the 080 to 120 altitude range, with good efficiency, O2 mask not needed. A turbine would be a gas hog at these altitudes.
It is the economics of scale. There are no (real) turbines that are cheap. It cost almost as much to make a real 250HP aircraft turbo prop engine as a 1000hp one. I don't know your economics, but if you want a real jet than go out and get a used Citation I Jet (can be flown single pilot). Good bargains in Turbo props are the MU-2 Mitsubishi and the Cessna Conquest I, all can be had for less than a million, and you get two turbines.
You like the Texan II? It was originally developed by Pilatus, who also make a great single engine turbo prop for the civilan market, the PC-12. They are fairly new, been around for +15 years and have a very good reputation with the corporate aviation industry. They are like a single engine kingair.
http://en.wikipedia.org/wiki/Pilatus_PC-12
http://www.pilatus-aircraft.com/html/en/products/index_195.asp
(they cost about $4.3 million new and hold value, about min $2.6 mil + for used.)
I'm guessing you are not paying to fly, insurance, hanger, maintenance and fuel right now? Insurance and gas will be way more for a turbine. Tom bottom line these little turbo prop engines are frankly toys, like you would put on a model RC plane, not one carrying humans. There is no fuel control, real RPM control and even torque gauge. It's a jury rig.
RV's are FAST fun planes. Take a fairly inexpensive proven new 160HP or 180HP Lyc, fixed or hyd prop and you will have a fun, high utility plane, with great performance that exceeds most of the GA fleet. Van's philosophy is fun on a budget. You don't need a turbine to have fun. If you want to just fly high and suck oxygen and travel great, but RV's really shine in the sport aviation arena, short fields, sportsman / gentleman's aerobatics and cross country, with great speed, range and payload. RV-10 has shown to be a nice 4 place plane.
The Fact is Innodyn has been around for a long time and has changed names and made endless promises, that they don't keep or are unrealistic. There is a another thread on the topic. At the top of the list is a search drop down menu, search for Innodyn. Look its not negative. In aviation blowing smoke and not realizing limitations of either yourself or equipment can end badly. If you want to be convinced, call Innodyn and talk to a sales person. They will take your money. For fun I wrote Innodyn two weeks ago and nothing. Their web site has not been updated since April 2007. The RV-8T has not flown as far as I know. Beware!
I don't know if you have flown any RV's but if not go out and fly one, any. You will be happy and think the piston engine is pretty cool. You can build an RV two seater for well $80,000 or less. The RV-10 is about $150k? It all depends on what you put into it. You can find used engines, props, rebuild them yourself, etc.. to save some cash, or go all new and gold plate and double the price.
If you are into turbines the Allison (now Rolls Royce) 250 (400hp) and the Garrett TPE31 (600-1100hp) could be good turbines if you could find one. Of course the best is the PT6, but they will cost more than I think you want to spend. Really I am quite serious it will be cheaper to go out and buy the used turbine airplane, even a Cessna Caravan ($2 mil new, $1 mil used), than make one.
Well that settles it:
SFC (lb/hp.hr)
Innodyn 0.65 @ cruise
Diesel 0.36 @ BEP
Rotax 0.48 @ MCP
A Lyc IO-235 or Continental IO-200 with FADEC for a UAV would be in the Rotax range or better 0.45 @ cruise.
The other article was written in 1995, but still has valid points I think we have rehashed here.