RV-8 Turbine update

[frankh]

I can't wait to hear some specs on this motor.

All the best,

Frank

[kcameron]

It's been about a month since flight testing was supposed to resume. Has the RV-8 flown again?

[cjensen]

Another bump for this thread...anything new with it???

[cjensen]

Sent two emails this morning to Innodyn. The first was to Charlie Sullivan (I think most of us know this name...), and the second was to the information request address. Both of them came back undeliverable because the mailboxes are full...

[kcameron]

What Innodyn doesn't seem to understand is that if they refuse to provide dyno/flight data and other information then those of us that are trying to figure out what's gong on will have to speculate based on what little information we have. I'd guess that very often, the speculation will paint a picture that looks worse than the truth. Also, Innodyn should try and understand that most of us speculators really hope that they've invented a great new engine. That's why we're bothering to pay attention to them.

Here's my speculation:
1) The RV-8 has flown again
2) The performance with the cheek inlets improved little compared to the naca duct. After all, how bad could it have been?
3) The performance is consistent with the engine producing 130 to 150 HP.
4) The builder has contacted Innodyn
5) He may not have been able to get a response
6) If he got a response, it was an assertion that something else is wrong with the installation.
7) The builder may be working on implimenting Innodyn's new modifications.
8) The builder may be discouraged and weighing his options but hasn't yet given up hope to the point that he's willing to go public with the results.

Innodyn, I hope you're listening. If you don't like my speculation, then please come up with some real info.

[cjensen]

I REALLY hope they are listening too! I'm all over the place with the direction I want to take for an engine. BUT, I'm far enough away from needing to choose, I can afford to be. Speculation is just that. I for one, hope that all eight of your items are wrong, but I know they may very well be true. Although, with no info to base them on, we shouldn't think too much about it. Innodyn has been notoriously late on everything they've said or promised. I'm glad I don't have money riding on one of these yet, but if they turn out to be legit (performance, fuel flow, price), my money would go to them in a heartbeat.

Everytime I fly the King Air at work, all I can think about is how sweet it would be to power my -7 with a turbine engine. I still watch the Innodyn video's once a week or so, dreaming of the day that this would become reality...

JIM, WHERE DID YOU GO??? WE NEED AN UPDATE!!

[gmcjetpilot]

Originally Posted by kcameron

Also, Innodyn should try and understand that most of us speculators really hope that they've invented a great new engine. That's why we're bothering to pay attention to them.

Well I don't think anyone wants anyone to come to harm or loose money or worse. Since this nice Gentalman has posted his pics, we are of course all pulling for him. However I will cop to being interested because I think its a train wreck, in the sense expectation and promises will crash into reality. There is no way its making the 7 gal/100hp. It also looks like engine operations, rpm/power/fuel management may be more difficult than a Lyc.

Originally Posted by cjensen

I REALLY hope they are listening too! <snip> Everytime I fly the King Air at work, all I can think about is how sweet it would be to power my -7 with a turbine engine. JIM, WHERE DID YOU GO??? WE NEED AN UPDATE!!

CJ are you kidding. Do you pay the bills at your company? What are those PT6's costing per hour, inspections, overhaul? Turbine = Nice , Turbine cost to an individual / sport pilot = sell kidney Yea I'm glad every time my RB211's spool-up, but it's hard to beat the suck, squeeze, bang, blow of the Lyc. For a 100-260 hp engine that does not make a living and flys 100-150 hours a year, tops, a piston engine is hard to beat. Heck even Lycs are making a living flying pipe line, freight, charters and small airlines. I'v been involved with piston aircraft fleets of close to 40 and most where Lycs, they do earn their keep.

There is no doubt turbines are sexy, but so is a Ferrari, Lamborghini and that new $400,000 Rolls Royce but its not like you will buy one so the wife can all kids to soccer practice and get groceries. Unless there is a technological breakthrough, a new "Paradigm" if you will, I hate that word but it fits here, than turbines will never be for average pilot/plane owners. Its like getting your own Nuclear reactor for your house, nice idea but not practical. The BEST you can do is find a old Lear, Citation, MU2, King-air, European Fighters/Trainer to get your Turbine jollies off.

What was it, 10-15 year ago, you could get a Casa Jet, Fuga Magister (V-tailed, tandem, later made into the personal ParisJet), L-29 or one of those Brit trainer/attack jets like the Provosts, for less than a RV cost today. They are still Cheap. I remember the first import L-39's turbofan trainer/attack (looks like a Douglas A-4), they cost less than $100,000. Now insurance, fuel and practicality come into effect, but if I wanted a jet I'd buy one already flying, it would be cheaper and actually do something than a home made turbine that is trying to only be a piston engine replacement.

Jets/Turbines are made to go real fast or haul lots of stuff. The RV airframe is not really suitable match. The best Kit plane/Turbine is the Lancair Prop-Jet with a used Walter (PT6 copy). You are looking at $500,000-$750,000. Now you have a pressurized personal 4 place plane. Makes sense.

I am looking at the VLJ's (very light jets). The Diamond, Maverick, Vantage, Eclipse, Adams and Cirrus jet. We shall see if the reality and dream end up in the ditch again or it takes off. Cheap Turbines are nice idea, but most of the improvement is with the 900-2000 lb thrust turbofan engines. By today's standards, they have to get cheaper, both initial purchase & operation cost, by a factor of 4-10 times before you and I can afford one. I have looked into the little 200-300lb thrust APU/Drone Jet engines and they are too small. I don't want to fly a BD-5 sized plane because frankly they are dangerous. The accident rate speaks for itself.

[cjensen]

Originally Posted by gmcjetpilot

<snip>It also looks like engine operations, rpm/power/fuel management may be more difficult than a Lyc.

WHY?

Originally Posted by gmcjetpilot

CJ are you kidding. Do you pay the bills at your company? What are those PT6 cost per hour? Turbine = Nice , cost to an individual / sport pilot = sell kidney Yea I am glad every time my RB211's spool- up, but it's hard to beat the suck, squeeze, bang, blow of the Lyc.

Well, you sniped out the last part of my post about DREAMING of this happening one day. I hope it does, but fully expect that it wont. BUT comparing operating costs between the 750shp PT6 and the 185hp Innodyn is certainly apples to oranges. Turbines are nice, and I thoroughly enjoy flying them at work...because I DON'T pay the bills. I know that the fuel buen claims from Innodyn are probably far fetched based on what well known turbines burn. The burn is going to be too high to make it work with the small tanks of an RV.

It is nice to DREAM though!

[gmcjetpilot]

I hear you chad. The reason for the power management issue is, as you know you have fuel, prop (torque) control (and fuel control). In a real turbine you have torque reading, hydraulic prop and a fairly complicated fuel controller.

The Innodyn has nothing or very rudimentary controls that don't work together. For example MT I believe does not approve of the application.

>No torque meter
>You have to set the fuel (w/ little or no protection)
>Direct prop - turbine (gear box) connection (not like a PT6)
>No auto ATMO compensation, have watch TIT (turbine inlet temp)
>Slow acting elec "constant speed" prop (rpm not torque control)

My worry is a pilot will be subject to:
>hot start
>over-speed
>"lug" (hung, no acceleration, un-spool)
>high egt and burning it into molten metal.

From what I gather they have constant RPM engine. So its just spooled to near 100% all the time and thrust (torque) is managed with the electric MT prop! Boy if that prop slaps to low pitch or high pitch at the wrong time it could be bad. Like I said MT is not on board. Could be wrong but that is what I heard.

I gather the pilot needs to manipulate the prop and fuel in concert (very carefully). The pilot must add pitch as you add fuel "manually". Well that is cool and takes some lever jocking, but without a real hydraulic prop and fuel controller with feedback/control between prop and fuel it might be a bit touchy.

Lets face it, a Lyc is a single lever engine. Leave the prop (if you have it) and mixture full forward and move the back knob and fly all day. At worst run at 2,700 rpm and burn way to much fuel. The penalty of doing some wacky-dos with the throttle or prop on the Innodyn may be bad? (loss of engine / power)

Look I'll cop to being a Lycoming fan. I am also use to jets w/ automatic engine management, auto start, over temp and over speed protection. Jets are easier to manage than props, but with the old Garrett's TPE331, they where fairly mature engines and had to be watched. Like the Innodyn they are direct drive engines. The PT6 is the easiest, most forgiving turbine you can fly. That is why they are so popular and successful.

Look at early jets that seemed to crash. The pilots did not understand the lag time to spool the old jet engine for a go around or arrest high sink rate close to the ground. The Innodyn is an "early jet" and seems they have done it on the cheap. They also are relying on a electric prop that is not designed or intended to be used like this. Elect props are slow to react and this as I worry. It may cause a problem. Hope I am wrong.

[cjensen]

Good post George. I agree with everything but one thing...according to Innodyn's website, the fuel is fully computer controlled. Here's the words from that page-

Piloting/Controls

Innodyn Turbines: An IntroductionFlying an Innodyn Turbine is much simpler than you
might think.

There are 2 basic controls to Innodyn Turbines ? the propeller RPM throttle and the propeller pitch. The computer manages the amount of fuel the Turbine draws, and alerts the pilot with a warning light if too much power is being requested. The computer control will not let the Turbine over-heat, and it will not let the Turbine over-speed.

Start
To start the Turbine, simply put the propeller to zero pitch and turn the starter key. The computer completes the start sequence, gradually spinning the propeller, adding fuel and turning on the igniter.

Once the Turbine is started, set the RPM lever and add propeller pitch to generate power. Instead of flying with the throttle, we recommend that you initially use only propeller pitch. The computer will handle fuel control and the Turbine?s operation. Because the Turbine is directly spooled, there is no noticeable lag in changing propeller RPM and the aircraft is quite responsive.

Taxi/Takeoff
To taxi, add a modest amount of pitch to the propeller to maintain a safe ground maneuvering speed. To take off, line up on the center line, and add propeller pitch. The propellers we recommend are able add pitch quite quickly, and the airplane will rapidly gain takeoff speed. After takeoff, simply maintain safe airspeeds. If you want to slow your climb rate, take a little bit of pitch out.

It will not be possible to accidentally enter a negative pitch into the propeller while airborne, as this would be a very alarming development.

The pilot should quickly have the ability to manage their takeoff roll, and their rate of climb.

Cruise
The Innodyn Turbine will cruise comfortably at 100% of power, and so it is not necessary to decrease either propeller RPM or pitch. Our Turbines actually operate most efficiently at full power, so there isn?t a compelling economic reason to decrease the power either. Obviously, you should not exceed Vne for your aircraft. Another important benefit of Innodyn Turbines is that they continue to produce power very effectively at higher altitudes.

Landing/Go-around
The landing process is relatively straightforward, and allows the pilot good control over approach speeds, landing speed, and rollout. Approaching the airport one gradually decreases propeller pitch to obtain the desired pattern speed, and likewise manages pattern and approach speed by making modest adjustments in propeller pitch. Innodyn?s pilots report that they have relatively quickly learned how to dial in a desired speed. On short final the pilot either continues gradually decreasing propeller pitch or adds propeller pitch and executes a go-around. As you fly the approach at a proper margin above stall speed, adding sufficient propeller pitch to produce additional thrust and execute a go-around is quite a quick process.

Because the Innodyn Turbine is directly driven, rather than spooled, there is virtually no lag associated with increasing speed. Likewise, because you want to land with plenty of power available, we don?t advise significantly decreasing propeller RPM during approach.

After landing, the pilot can continue decreasing propeller pitch to slow the landing roll. With experience, a pilot can very effectively shorten the landing roll.

I have not heard that the MT was not intended for this. I thought they had worked with MT to develop the prop...don't know.