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Innodyn Turbine Engines
- Thread starter RV_7A
- Start date
Baja_Traveler
Well Known Member
RV_7A said:
Tom Maxwell
Well Known Member
Keep the positive outlook
Jeff, I admire your positive outlook on this possible solution. Where would experimental aviation be if everyone took the position that "it" won't work?
There are a lot of people looking at this and other alternative solutions and I for one hope the solutions pan out as advertised. From what I read about the auto conversions, diesels, and the turbine, I have come to the conclusion that people with more engineering background than I are the most negative about the trubine solution. Even if the reported fuel consumptions are archieved, they still don't match up to the economy of a piston engine. Another thing to consider is that the turbine fuel consumption will be almost the same while sitting on the ground at idle as in cruise flight. Best case, 14 to 15 gallons per hour while sitting on the ground, taxiing, and in flight represents a pretty signifacant cost deficit over piston engines.
The engine is cool, sounds great, and does have many advantages. The cost of operation is still the big question mark and as others have said, the Innodyne web site has been short on hard data and hasn't changed much in the past year.
It will be cool if Innodyne can deliver a cost effective and reliable solution.
Keep your fingers crossed!
Jeff, I admire your positive outlook on this possible solution. Where would experimental aviation be if everyone took the position that "it" won't work?
There are a lot of people looking at this and other alternative solutions and I for one hope the solutions pan out as advertised. From what I read about the auto conversions, diesels, and the turbine, I have come to the conclusion that people with more engineering background than I are the most negative about the trubine solution. Even if the reported fuel consumptions are archieved, they still don't match up to the economy of a piston engine. Another thing to consider is that the turbine fuel consumption will be almost the same while sitting on the ground at idle as in cruise flight. Best case, 14 to 15 gallons per hour while sitting on the ground, taxiing, and in flight represents a pretty signifacant cost deficit over piston engines.
The engine is cool, sounds great, and does have many advantages. The cost of operation is still the big question mark and as others have said, the Innodyne web site has been short on hard data and hasn't changed much in the past year.
It will be cool if Innodyne can deliver a cost effective and reliable solution.
Keep your fingers crossed!
LifeofReiley
Well Known Member
Turbine & Rockets
I feel the fuel burn is equal to and/or could be less than the 540 fuel burn. After all we will not need the FADEC or other aftermarket computers to manage the fuel burn and at 75% will be SMOKING at 20K feet.
I feel the fuel burn is equal to and/or could be less than the 540 fuel burn. After all we will not need the FADEC or other aftermarket computers to manage the fuel burn and at 75% will be SMOKING at 20K feet.
LifeofReiley
Well Known Member
Turbine & Rockets
The truth is the Rocket drivers will not disclose their true fuel burn! I have been around 540's, I know what they burn at full throttle plus they can't do what this turbine can do performance wise! (less travel time less fuel)
The truth is the Rocket drivers will not disclose their true fuel burn! I have been around 540's, I know what they burn at full throttle plus they can't do what this turbine can do performance wise! (less travel time less fuel)
gmcjetpilot
Well Known Member
Innodyn not ready for prime time
Engine: base price for the engine $28,000 (185hp) $29,500 (205hp)
Installation kit: mount, fuel cont'l, ign, exhaust, cowl> $8,000-$12,000 (est*)
Prop: electric c/s required> $9,000-$10,000
Total: approx $50,000
*(Subtract may be $2 grand from the $5 grand Van's finish kit)
Initial Cost: No doubt cool, but not ready for prime time until an installation kit is developed for the RV. I called Innodyn and had a nice long talk with a Gentleman in sales at Innodyn and was told there are two separate companies, independent from Innodyn, developing RV kits for their engines. The previous company that was developing a RV kit dropped out.
I call the company that dropped out of making a RV kit and was told the cost to develop and manufacture a production kit kept rising. The figure I recall was they were up to $12,000 and claimed they still could not even make money at that kit price, so they dropped out. Innodyn claims the new players will have much lower kit price, around $8,000? I believe electrical power is needed to drive the redundant fuel controllers. I do not believe they have mechanical fuel controllers. The igniter is ship powered to start. I would assume it does not req continuous ignition. From the pictures it looks like electrical power is from a little Denso alternator. So dual batteries and other systems may cut into the low basic engine weight.
I was told that it is about 7 gal/hr for every 100 hp (company claim no data). So a 185 hp wide open would be 7 x 185/100 = 13 gal/hr. That is the same as a 180HP Lycoming? (Sounds low for a turbine) However, in theory where it really should shine is flying at Flight Levels (FL). However at FL250 OAT is -30C (-54F), and you will be sucking O2 to stay coherent (alive). You would need to contend with cabin temp, frosted canopy, IFR clearance above FL180 and DME above FL240. Not my idea for fun. You are still limited by Vne.
I am guessing the Turbine may not be flat rated (derated) at take off and will be altitude limited. They don't give much real data on HP vs Altitude and what temp limits it has and typically operates at.
Also how would the turbine & electric prop combo work for formation flying with other RV's (piston power) and aerobatics? Don?t know how that would go over (pun intended).
Cheers George
Engine: base price for the engine $28,000 (185hp) $29,500 (205hp)
Installation kit: mount, fuel cont'l, ign, exhaust, cowl> $8,000-$12,000 (est*)
Prop: electric c/s required> $9,000-$10,000
Total: approx $50,000
*(Subtract may be $2 grand from the $5 grand Van's finish kit)
Initial Cost: No doubt cool, but not ready for prime time until an installation kit is developed for the RV. I called Innodyn and had a nice long talk with a Gentleman in sales at Innodyn and was told there are two separate companies, independent from Innodyn, developing RV kits for their engines. The previous company that was developing a RV kit dropped out.
I call the company that dropped out of making a RV kit and was told the cost to develop and manufacture a production kit kept rising. The figure I recall was they were up to $12,000 and claimed they still could not even make money at that kit price, so they dropped out. Innodyn claims the new players will have much lower kit price, around $8,000? I believe electrical power is needed to drive the redundant fuel controllers. I do not believe they have mechanical fuel controllers. The igniter is ship powered to start. I would assume it does not req continuous ignition. From the pictures it looks like electrical power is from a little Denso alternator. So dual batteries and other systems may cut into the low basic engine weight.
I was told that it is about 7 gal/hr for every 100 hp (company claim no data). So a 185 hp wide open would be 7 x 185/100 = 13 gal/hr. That is the same as a 180HP Lycoming? (Sounds low for a turbine) However, in theory where it really should shine is flying at Flight Levels (FL). However at FL250 OAT is -30C (-54F), and you will be sucking O2 to stay coherent (alive). You would need to contend with cabin temp, frosted canopy, IFR clearance above FL180 and DME above FL240. Not my idea for fun. You are still limited by Vne.
I am guessing the Turbine may not be flat rated (derated) at take off and will be altitude limited. They don't give much real data on HP vs Altitude and what temp limits it has and typically operates at.
Also how would the turbine & electric prop combo work for formation flying with other RV's (piston power) and aerobatics? Don?t know how that would go over (pun intended).
Cheers George
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I would be suspicious of the fuel burn figures. When I did my engineering course I remember some figures being talked about. They were that a Piston engine is approx 95% mechanically efficient I.E it takes about 5% of the power it produces to keep itself running. A turbine is about 33% efficient so it takes 66% of the power it produces to keep itself running. This basically means it will have a higher fuel burn for the same power output compared to a piston engine. The advantage is that a turbine can make heaps and heaps of power out of a small engine.
f1rocket
Well Known Member
I don't really appreciate being called a liar on this forum. All of the Rocket guys will be glad to share their fuel burn data with you. I'll even send you the fuel burn table out of the Lycoming manual if you'd like.LifeofReiley said:
I've been told, but I'm not an engine expert, that the fuel burn for the turbine is more like 10 gals per hour per 100 HP, and as someone else pointed out, that's on the ground as well as in the air. We don't run at full throttle very often in these airplanes. Yea, it will gulp 17 to 19 GPH at full throttle down low, but your eyes will be pulled to the back of your head. There's no need to go full throttle with this engine in this airframe. We operate very happily in the 60% to 70% power range with fabulous economy.
You may know 540's but I suspect not when it's in a Rocket airframe. However, with all that being said, I still think the turbine is a cool engine and IF they can get the fuel economy that they claim, I think they are a real viable engine. Heads turn when that turbine spools up.
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Highflight
Well Known Member
RV_7A said:
I think the problem for most people is that it's going to take a LOT of other advantages to get over that "fuel thing".
Lest you think I'm some kind of Lycoming "groupie", I will tell you that I tried really, really hard to talk myself into one of the other engine alternatives before realizing that the Lycoming is the only engine that makes sense if you want to actually FLY the aircraft sometime in the next decade.
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Rick of Austin
Well Known Member
Real IO-520 Fuel burns
As a data point last week I flew 1.5 hours in a Bellanca at 2400rpm and 24 inches and the fuel burn was 15.5-16 gph according to the fuel flow meter. This was at 3500 feet leaned 50 degrees rich of peak.
Lets see at San Antonio international prices that is $70.00 per hour in fuel!!!
As a data point last week I flew 1.5 hours in a Bellanca at 2400rpm and 24 inches and the fuel burn was 15.5-16 gph according to the fuel flow meter. This was at 3500 feet leaned 50 degrees rich of peak.
Lets see at San Antonio international prices that is $70.00 per hour in fuel!!!
LifeofReiley
Well Known Member
Oops
Must have pushed a button for F1Rocket...
I apologize if anyone was affended.
I stand corrected...
Most large engine... high performance RV and Rocket owners, to include most high performance general aviation aircraft owners do not like talking about their fuel burn. It can give them heartburn or maybe indigestion.
Must have pushed a button for F1Rocket...
I apologize if anyone was affended.
I stand corrected...
Most large engine... high performance RV and Rocket owners, to include most high performance general aviation aircraft owners do not like talking about their fuel burn. It can give them heartburn or maybe indigestion.
high speed flutter
I wanted a turbine too but I think that getting alot more speed at higher altitudes may not work as well as some might think. I would be worried that I could go alot faster and that flutter might become an issue. The indicated speed might not be that much but keep in mind what alt. you are at. If I recall smokeyray experienced some flutter in his -4 at around 10k in a shallow dive...
Just something to think about...I would love the sound and smell of the thing though!
I wanted a turbine too but I think that getting alot more speed at higher altitudes may not work as well as some might think. I would be worried that I could go alot faster and that flutter might become an issue. The indicated speed might not be that much but keep in mind what alt. you are at. If I recall smokeyray experienced some flutter in his -4 at around 10k in a shallow dive...
Just something to think about...I would love the sound and smell of the thing though!
mlw450802
Well Known Member
I'm with you on the smell and the sounnnnnnnnnnnd! I'm not brave enough (read flush enough) to try the innodyn for reasons of anticipated operating costs but then operating costs (anticipated) are one of the main criteria for my building in the first place.
However, I am not going to try to talk anyone out of trying this engine. I would welcome the experimentation from anyone who is going into it with eyes wide open. The data gathered would be invaluable and would help to cement the decisions for all the rest of us. As long as Innodyn is forthright with their claims (a huge "Caveat Emptor") then go for it.
Good luck to anyone who chooses to go this route and be sure to wave to us as you whistle past.
-Mike
Oh Yeah. I found a solution to achieve the Jet-A smell: Just stand near your grill when you have lit off the charcoal lighter fluid!
However, I am not going to try to talk anyone out of trying this engine. I would welcome the experimentation from anyone who is going into it with eyes wide open. The data gathered would be invaluable and would help to cement the decisions for all the rest of us. As long as Innodyn is forthright with their claims (a huge "Caveat Emptor") then go for it.
Good luck to anyone who chooses to go this route and be sure to wave to us as you whistle past.
-Mike
Oh Yeah. I found a solution to achieve the Jet-A smell: Just stand near your grill when you have lit off the charcoal lighter fluid!
rvpilot
Well Known Member
Flight Testing
Well, when presented with this opportunity, why did the powers to be at Innodyn turn down the offer?!!? After all, the plane was already fitted with the computer, flow system, mount, cowl, everything needed to almost immediately start testing! Seems kinda strange to me!
While this may prove to be a very successful venture in the distant future, I think everyone needs to proceed very cautiously for the moment!
Bill Waters
You've hit on an interesting point here. It seems if the opportunity presented itself, Innodyn would welcome the chance to gather valuable flight data from an RV flying with one of thier turbines. After all, this information could be used to settle a lot of the debate that has been plaguing them of late.
Well, when presented with this opportunity, why did the powers to be at Innodyn turn down the offer?!!? After all, the plane was already fitted with the computer, flow system, mount, cowl, everything needed to almost immediately start testing! Seems kinda strange to me!
While this may prove to be a very successful venture in the distant future, I think everyone needs to proceed very cautiously for the moment!
Bill Waters
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Thanks everyone. It's nice to see a few optimistic folks out there in the "experimental" world. Any many thanks to Burt Rutan and his venture into unchartered territory. If it wasn't for people like him and Mr. Van himself, we would still be gluing sticks together and laying cloth. (no offense to anyone building a bird nest please) I hope that anyone that has positive news pertaining to these Turbines will post it here. I'll do the same as I learn. Keep in mind I haven?t lost hope of having a Superior XP 360 plus I my plane but I've always admired new technology and encourage anyone involved in projects like these. It what makes this hobby so interesting.
atreff
Well Known Member
Innodyne visit at SnF
I spent some time in the Innodyne booth at SnF and was disturbed by the lack of information, and the confusion among the team in the booth. The white haired gent could not adequately tell me how the turbine was operated by the pilot, nor the theory of operation, and he was the director of business development. I talked to the test pilot, who complained that he seemed to be the only staff member who knows how to operate the engine. I asked both gents about who engineered the metallurgy of the turbine and burner cans. Who engineered the bearing seals, what kind of seals, and were they cooled or pressurized by bleed air. How was the shaft balanced? What was it made of? Neither the business guy nor the test pilot guy could answer that either. Broad platitudes were thrown around like,
"We hired the best in the business," 'It's the best thing out there.'
I also asked what the difference was between the 160 HP and the 200HP model. Same everything was the answer-turbine, bearings, cans, shaft. So, I asked how are they getting to the higher HP number, running hotter? No was the answer. Running faster? No, same speed was the answer. TBO the same? Yes. Hmmm...160 same temp and speed, just using less fuel than the 200HP with the same TBO and temps. I probably don't know much about turbines, but this seemed funny to me. Ya can't get something for nothing.
The also said that the prop and governor controlled the speed. When I asked about what happens if the governor failed, no one really had an answer as to how the pilot would control the turbine. I must have gotten them on a bad day or something, because the procedure was not clear between Innodyne's business dept and their flight testing dept. I'm sure they must have this worked out.
They may have the best product out there, but since I am a sales professional in real life, I walked from their tent wondering how they're ever going to get to market if they cannot express themselves to their customers.
I asked why the RV-4 test bed was absent, and the reply was nebulous as well. Innodyne has been at this show for (I think) 3 years now and they still seem to be where they were when I first laid eyes on them. I wish them well, but I've got to see some accelerated life tests, more than one or two flying, it's a great deal of money and time to invest in something so unknown.
I spent some time in the Innodyne booth at SnF and was disturbed by the lack of information, and the confusion among the team in the booth. The white haired gent could not adequately tell me how the turbine was operated by the pilot, nor the theory of operation, and he was the director of business development. I talked to the test pilot, who complained that he seemed to be the only staff member who knows how to operate the engine. I asked both gents about who engineered the metallurgy of the turbine and burner cans. Who engineered the bearing seals, what kind of seals, and were they cooled or pressurized by bleed air. How was the shaft balanced? What was it made of? Neither the business guy nor the test pilot guy could answer that either. Broad platitudes were thrown around like,
"We hired the best in the business," 'It's the best thing out there.'
I also asked what the difference was between the 160 HP and the 200HP model. Same everything was the answer-turbine, bearings, cans, shaft. So, I asked how are they getting to the higher HP number, running hotter? No was the answer. Running faster? No, same speed was the answer. TBO the same? Yes. Hmmm...160 same temp and speed, just using less fuel than the 200HP with the same TBO and temps. I probably don't know much about turbines, but this seemed funny to me. Ya can't get something for nothing.
The also said that the prop and governor controlled the speed. When I asked about what happens if the governor failed, no one really had an answer as to how the pilot would control the turbine. I must have gotten them on a bad day or something, because the procedure was not clear between Innodyne's business dept and their flight testing dept. I'm sure they must have this worked out.
They may have the best product out there, but since I am a sales professional in real life, I walked from their tent wondering how they're ever going to get to market if they cannot express themselves to their customers.
I asked why the RV-4 test bed was absent, and the reply was nebulous as well. Innodyne has been at this show for (I think) 3 years now and they still seem to be where they were when I first laid eyes on them. I wish them well, but I've got to see some accelerated life tests, more than one or two flying, it's a great deal of money and time to invest in something so unknown.
Tandem46
Well Known Member
Unimpressed
I too visited the Innodyne tent at S&F and came away very unimpressed. Something about their display/presentation just looked amature (I got the impression that they grabbed a couple of their turbines, two card tables, and some folding chairs and just showed up). I'm very happy with my Aerosport IO-360, but for JetA burning powerplants I think Deltahawk would be the "safer" bet. They seem to be making some real progress, albeit slow. And the Honda engine is still out there some where. I talked to the guy at the TCM tent at S&F and he said Honda is still working on that engine. Their test bed in Mobile AL is a Cessna 337 and he said the last time he saw it, it still had the Honda engine up front. Plus Japan recently opened up a new piston engine development center over there.
On another note.......
It's too bad that a multi-million dollar company like Williams can't take the engine that was originally designed for the Eclipse 500 and develop it into a turboprop for the light single engine market. It's also too bad that the Government can't or won't sue TCM and Williams and get the millions of dollars of taxpayers money back that they paid them for the GAP(general aviation propulsion) program of 1998, of which neither delivered.
Tobin
I too visited the Innodyne tent at S&F and came away very unimpressed. Something about their display/presentation just looked amature (I got the impression that they grabbed a couple of their turbines, two card tables, and some folding chairs and just showed up). I'm very happy with my Aerosport IO-360, but for JetA burning powerplants I think Deltahawk would be the "safer" bet. They seem to be making some real progress, albeit slow. And the Honda engine is still out there some where. I talked to the guy at the TCM tent at S&F and he said Honda is still working on that engine. Their test bed in Mobile AL is a Cessna 337 and he said the last time he saw it, it still had the Honda engine up front. Plus Japan recently opened up a new piston engine development center over there.
On another note.......
It's too bad that a multi-million dollar company like Williams can't take the engine that was originally designed for the Eclipse 500 and develop it into a turboprop for the light single engine market. It's also too bad that the Government can't or won't sue TCM and Williams and get the millions of dollars of taxpayers money back that they paid them for the GAP(general aviation propulsion) program of 1998, of which neither delivered.
Tobin
Jconard
Well Known Member
Quote:
"It's also too bad that the Government can't or won't sue TCM and Williams and get the millions of dollars of taxpayers money back that they paid them for the GAP(general aviation propulsion) program of 1998, of which neither delivered."
I normally don't respond to such, but I must in this case. There are enough lawsuits. Government contractors who do their best, but fail, in a contract for development, have not done anything wrong, and should hence not be sued. You cannot mandate innovation.
This sort of plattitude is dangerous and ignorant...it encourages politically motivated government employees (US Attorneys) to make life miserable for solid aviation companies.
Imgine if a whole fleet of homebuilt and low cost GA planes had turbines. At first it would be great. But after a decade of the typical neglect, and misinformed tinkerings that piston engines endure, the much less forgiving turbines would begin to fail, exposing manufactures to huge liability.
Remember that the airplnes on which those things are so reliable today are fleet maintained using excellent process and practice. Much different from the GA and Experimental market. Remember we had a two week long debate the other month about the necessity of fuel filters!
Then it would be too bad that the government couldn't or wouldn't sue Williams for the defective design of a turbine, which was intolerant of compromised fuel; after all they could have foreseen or anticipated such systems if they sold to the experimental market. Just one example, but it is why Pratt and Williams prefer to supply to sophisticated users.
"It's also too bad that the Government can't or won't sue TCM and Williams and get the millions of dollars of taxpayers money back that they paid them for the GAP(general aviation propulsion) program of 1998, of which neither delivered."
I normally don't respond to such, but I must in this case. There are enough lawsuits. Government contractors who do their best, but fail, in a contract for development, have not done anything wrong, and should hence not be sued. You cannot mandate innovation.
This sort of plattitude is dangerous and ignorant...it encourages politically motivated government employees (US Attorneys) to make life miserable for solid aviation companies.
Imgine if a whole fleet of homebuilt and low cost GA planes had turbines. At first it would be great. But after a decade of the typical neglect, and misinformed tinkerings that piston engines endure, the much less forgiving turbines would begin to fail, exposing manufactures to huge liability.
Remember that the airplnes on which those things are so reliable today are fleet maintained using excellent process and practice. Much different from the GA and Experimental market. Remember we had a two week long debate the other month about the necessity of fuel filters!
Then it would be too bad that the government couldn't or wouldn't sue Williams for the defective design of a turbine, which was intolerant of compromised fuel; after all they could have foreseen or anticipated such systems if they sold to the experimental market. Just one example, but it is why Pratt and Williams prefer to supply to sophisticated users.
Tandem46
Well Known Member
Jconard,
You seem to be making two points, one about the feasibilty of turbines in general aviation, and the other about sueing. I'll conceed that there are far too many lawsuits and I'll maybe even concede your point about the compatibilty of turbines in general aviation. But the fact is our money, US taxpayer money was given to TCM and Williams and they have nothing to show for it. Those two companies took that money knowing full well what it meant and what their part of the deal entailed. (I won't go into the details fo the GAP program here, but there is plenty of it archived on the internet) There would be nothing wrong with the government, on behalf of the US taxpayer, telling them to deliver or give the money back. This wasn't free money for them to do with as they will. TCM really dropped the ball. They won't take their engine to production because they feel there isn't a big enough market. They can't tell me they didn't know that at the time. Companies as large as TCM shouldn't need government incentive money to develop a new engine anyway. They should do it one their own because they want to and because they want to improve their product like every other segment of industry out there but they've been too happy with the status quo for too long. (Lycoming is guilty of this too). You hear a lot of complaints about how aviation piston technology hasn't progressed much in the last fifty years. So if we taxpayers give them millions and nothing changes, then we have every right to demand the money back.
Tobin
You seem to be making two points, one about the feasibilty of turbines in general aviation, and the other about sueing. I'll conceed that there are far too many lawsuits and I'll maybe even concede your point about the compatibilty of turbines in general aviation. But the fact is our money, US taxpayer money was given to TCM and Williams and they have nothing to show for it. Those two companies took that money knowing full well what it meant and what their part of the deal entailed. (I won't go into the details fo the GAP program here, but there is plenty of it archived on the internet) There would be nothing wrong with the government, on behalf of the US taxpayer, telling them to deliver or give the money back. This wasn't free money for them to do with as they will. TCM really dropped the ball. They won't take their engine to production because they feel there isn't a big enough market. They can't tell me they didn't know that at the time. Companies as large as TCM shouldn't need government incentive money to develop a new engine anyway. They should do it one their own because they want to and because they want to improve their product like every other segment of industry out there but they've been too happy with the status quo for too long. (Lycoming is guilty of this too). You hear a lot of complaints about how aviation piston technology hasn't progressed much in the last fifty years. So if we taxpayers give them millions and nothing changes, then we have every right to demand the money back.
Tobin
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I did some research a while back on the Innodyn engine, and I wasn't pleased with what I found.
Innodyn was previously known as Affordable Turbine Power (ATP). It would appear their reputation was somewhat less than spotless.
That alone was enough to put me off buying one, but I was still curious about the technology of the engine itself, so I kept looking.
Apparently the engine is based on the Solar T-62 APU, which was designed for use in a couple of military helicopters and never offered to the general public on the commercial market.
Some information on the T-62 can be found here. In summary, it's an APU designed to operate between sea level and 15,000', run at ~56,000 rpm and produce about 70 SHP.
How they intend to ramp that up to over 200 HP is both beyond me and something I find somewhat scary, to be honest.
Finally, there's a good write up about using APUs as primary propulsion units here. This covers my thoughts on converting APUs pretty well, based on what I learned about them in the classes I took relating to the history, design and operation of gas turbine engines.
Important bits quoted below:
After finding out all of the above, I decided that I not only wouldn't use an Innodyn engine in any project I built, I also wouldn't set foot in any aircraft powered by one. I'm open to experimental concepts and alternate powerplants, but an old surplus military helicopter APU that is probably being run significantly out of design spec is a bit too "out there" for me.
If any of the information above is inaccurate, I welcome corrections. I had to do a bit of digging to find all of this out, and if I can save others from having to do the same or keep them from finding out "the hard way", I think that's a good thing.
Ultimately it's a matter of deciding what best suits your needs, but I'd strongly suggest staying far away from any converted APUs. They just weren't designed with that kind of operation in mind, and no amount of creative engineering is going to change the fact that the engine core was purpose built for a very specific (and different) kind of operation in mind.
Innodyn was previously known as Affordable Turbine Power (ATP). It would appear their reputation was somewhat less than spotless.
That alone was enough to put me off buying one, but I was still curious about the technology of the engine itself, so I kept looking.
Apparently the engine is based on the Solar T-62 APU, which was designed for use in a couple of military helicopters and never offered to the general public on the commercial market.
Some information on the T-62 can be found here. In summary, it's an APU designed to operate between sea level and 15,000', run at ~56,000 rpm and produce about 70 SHP.
How they intend to ramp that up to over 200 HP is both beyond me and something I find somewhat scary, to be honest.
Finally, there's a good write up about using APUs as primary propulsion units here. This covers my thoughts on converting APUs pretty well, based on what I learned about them in the classes I took relating to the history, design and operation of gas turbine engines.
Important bits quoted below:
After finding out all of the above, I decided that I not only wouldn't use an Innodyn engine in any project I built, I also wouldn't set foot in any aircraft powered by one. I'm open to experimental concepts and alternate powerplants, but an old surplus military helicopter APU that is probably being run significantly out of design spec is a bit too "out there" for me.
If any of the information above is inaccurate, I welcome corrections. I had to do a bit of digging to find all of this out, and if I can save others from having to do the same or keep them from finding out "the hard way", I think that's a good thing.
Ultimately it's a matter of deciding what best suits your needs, but I'd strongly suggest staying far away from any converted APUs. They just weren't designed with that kind of operation in mind, and no amount of creative engineering is going to change the fact that the engine core was purpose built for a very specific (and different) kind of operation in mind.
I'm not a turbine expert by any stretch, but as a DAR I try to find out as much information as possible and have talked with several very experienced turbine mechanics. They all seem to agree with what you are saying. I have no problem with experimentation, after all that's what we are about. But let's all do a lot of homework in the direction of our experiment.
Mel...DAR
Mel...DAR
MarkEsterhuizen
Member
F1 Rocket C-GKRE 22/22 = 190 KIAS, 10.7 GPH. (55% Power)
Hi Everyone
I read through this topic and there is a lot of information here. I thought I would just add that a friend of mine, just delivered a RV10 airframe to these people that they intend to install one of their turbine engines in and use as a demonstrator. He made sure he was paid for the work before he delivered the airframe.
Joe Hine
C-FYTQ
I read through this topic and there is a lot of information here. I thought I would just add that a friend of mine, just delivered a RV10 airframe to these people that they intend to install one of their turbine engines in and use as a demonstrator. He made sure he was paid for the work before he delivered the airframe.
Joe Hine
C-FYTQ
Well its a good thing he is having them do the install because after I received the manual I realized I would have had to be an aeronautical engineer to decipher the installation instructions and apply them to an RV. Until they create a clear installation manual specific to the installation of their engine on an RV along with pictures and details I feel it will be a long time till the RV community warms up to this option.
Give em a break
I have watched the Innodyn thread with a lot of interest and I have read a lot of negativity. I hope that this soon changes. The engine is new and they will go through a learning curve. I don't think that Lycoming just came out of the box without some setbacks.
I have found that the people that typically build and fly RV's are good positive people that like to help others. This thread needs to change so that the people of Innodyn can use it to better their product and get support, only if it is moral support.
In my opinion it has the potential to be a wonderful engine and so far, it is the best product for our market that I have seen. At least they are giving an effort in order to provide our category of expirimental aircraft a turbine solution.
Please remember that they are not Lycoming and they never will be. They do have an interesting product that is unlike any other out there. If you are not interested in burning more fuel or using a turbine then just get off of ther backs or show us a better solution.
Lets get off of their case and give them some support. I know that some have had negative experiences with Innodyn but what is not mentioned in the forum is what steps have been taken to help the company improve.
I talked with them and they were very pleasant. If given the chance I would install one of their units in a heartbeat. they are familiar with this forum and they are trying to be a company that will have you knocking down the doors.
I have watched the Innodyn thread with a lot of interest and I have read a lot of negativity. I hope that this soon changes. The engine is new and they will go through a learning curve. I don't think that Lycoming just came out of the box without some setbacks.
I have found that the people that typically build and fly RV's are good positive people that like to help others. This thread needs to change so that the people of Innodyn can use it to better their product and get support, only if it is moral support.
In my opinion it has the potential to be a wonderful engine and so far, it is the best product for our market that I have seen. At least they are giving an effort in order to provide our category of expirimental aircraft a turbine solution.
Please remember that they are not Lycoming and they never will be. They do have an interesting product that is unlike any other out there. If you are not interested in burning more fuel or using a turbine then just get off of ther backs or show us a better solution.
Lets get off of their case and give them some support. I know that some have had negative experiences with Innodyn but what is not mentioned in the forum is what steps have been taken to help the company improve.
I talked with them and they were very pleasant. If given the chance I would install one of their units in a heartbeat. they are familiar with this forum and they are trying to be a company that will have you knocking down the doors.
Innodyne does have an interesting engine and I agree with the idea of your post however many people in experimental aviation have been burned by engine suppliers promising more than can deliver. Engines are high dollar items so understandably, people are wary.
My advice to anyone trying to sell engines, engine hardware, propellers etc. is:
1. Get an RV airframe and put your product on it. Fly it, develop it and prove it. THEN market it.
2. Don't use deposit money for product R&D. Keep it in the bank in case the customer wants a refund.
3. Keep your promises for delivery and performance. Any BS claims will be quickly thrashed on the 'net and you will lose credibility. Phone people back when you said you will.
4. If there are problems with delivery or hardware/ software, phone the customer and come clean. Any secrets in this industry will quickly surface and you will have ruined any chance of business success. A few bad stories on the 'net and everyone knows that they don't want to deal with you.
Ever wonder why Van's has been so successful? They follow every rule here.
I wish Innodyne every success. Wanna generate interest and get free advertising- fly a turbine powered RV to Aurora for a head to head against Van's demonstrators. They'll have instant credibility if it compares well.
My advice to anyone trying to sell engines, engine hardware, propellers etc. is:
1. Get an RV airframe and put your product on it. Fly it, develop it and prove it. THEN market it.
2. Don't use deposit money for product R&D. Keep it in the bank in case the customer wants a refund.
3. Keep your promises for delivery and performance. Any BS claims will be quickly thrashed on the 'net and you will lose credibility. Phone people back when you said you will.
4. If there are problems with delivery or hardware/ software, phone the customer and come clean. Any secrets in this industry will quickly surface and you will have ruined any chance of business success. A few bad stories on the 'net and everyone knows that they don't want to deal with you.
Ever wonder why Van's has been so successful? They follow every rule here.
I wish Innodyne every success. Wanna generate interest and get free advertising- fly a turbine powered RV to Aurora for a head to head against Van's demonstrators. They'll have instant credibility if it compares well.
hevansrv7a
Well Known Member
Piston Fuel Burn
Excuse the joke, but piston fuel burn is not rocket science. A lyc or similar will burn approx. 0.45 pounds per hp per hour of avgas. At 6 pounds per gallon, that is 7.5 gallons per hour for 100 horsepower. That is consistent with the approx. 8 gph in a C-150 at full rich, full throttle. The best you ever see in a piston engine is about 0.42 p/hp/hr for electronic controls, ideal conditions. Of course, at less than full throttle or richer than best mixture, the gph increases.
As to the efficiency of piston engines, only about 1/3 of the energy in the avgas is converted to mechanical power. Just look up the BTU's in gas and do the math yourself.
I don't know anything about turbines, let alone Innodyn's. I just want to get the terms of the dialogue on a solid footing.
h
Excuse the joke, but piston fuel burn is not rocket science. A lyc or similar will burn approx. 0.45 pounds per hp per hour of avgas. At 6 pounds per gallon, that is 7.5 gallons per hour for 100 horsepower. That is consistent with the approx. 8 gph in a C-150 at full rich, full throttle. The best you ever see in a piston engine is about 0.42 p/hp/hr for electronic controls, ideal conditions. Of course, at less than full throttle or richer than best mixture, the gph increases.
As to the efficiency of piston engines, only about 1/3 of the energy in the avgas is converted to mechanical power. Just look up the BTU's in gas and do the math yourself.
I don't know anything about turbines, let alone Innodyn's. I just want to get the terms of the dialogue on a solid footing.
h
gmcjetpilot
Well Known Member
Here is a real small turbine, and fuel burn.
http://www.cs-ent.ca/6334.jpg
http://www.cs-ent.ca/6334.htm
Fuel burn for a Allison 250-B15G is 0.697 to 0.706, which works out to be about 10 gal/hr. So on takeoff you are burning about 30 gal an hour. The sales ad says 20 gph, which sounds like a good average. So why turbines. Well it weighs 180 lbs and makes 317 hp. Similar later models weigh about 200 lbs make 420 HP! Nuff said. BUT there's more.
Also the turbine has altitude capability. It looses less HP with altitude and is effect by the cooler temps to a great degree. So the above SM 1019 (Basically a Cessna Bird Dog Liaison plane) has a FL250 service ceiling. That is the Joy of the turbine, not fuel burn. The joy is also reliability. Once you start getting into the 350-400 hp range turbines, they start to look good. What does a 450 HP Pistons engine look like. Joe private pilot in the lower HP ranges, say below 300 HP, is best served by the good old piston. That is why you don't see commercial small turbines for aircraft propullsion.
Lycoming makes 400-450 HP engines like the TIGO541, IO720 and IGSO540. They get pretty complicated and heavy, so the turbine premium $$ starts to pay its way onto aircraft commercial aircraft. After 450 HP forget it, piston engines are starting to get large, expensive and rare. I know some one will chime in about some aluminum block V8 or falconer V12 experimental engines. True, love'em but not cheap or small or light. Why don't we see the sky filled with V8's?
Cost: Turbine parts can cost $xx,xxx for one turbine stage? If you do a hot section and have a turbine or burner problem, its going to hurt. The good news is parts should go 6000 hours. TBO of the compressor, burner, gear box, fuel controller (HMU) and governor is either on condition or 2000-3500 hours. Hot section inspection is 1750 hours. Some turbine parts are life limited at 3000-6000 hours. So its not maintenance free. You can imagine what component inspections and an overhaul might cost.
Innodyn claims some amazing maintenance periods. Here is a large company like Allison, which has about 167 million hours on 29,000 units of the Allison 250 engines from 317hp to 650hp, talking about 3000 hour TBO's and Life limited parts of 6000 hours. Innodyn claims 5000 hours TBO, about 2000 better than the Allison.
This is a real turbine and about as small as you will find in a plane from the factory. Turbines really start to make sense when you get in to 600 to 1000 hp.
Than with the new turbo fans, cost and fuel burn are even less. With out the mess of a prop, the jet is the way to go. Anyone want to make a jet RV? Kidding,
George
Turbines are going to burn more per hp. I was just looking at an Allison 250-B15G 330 H.P in a 1976 SIAI MARCHETTI SM 1019:hevansrv7a said:
http://www.cs-ent.ca/6334.jpg
http://www.cs-ent.ca/6334.htm
Fuel burn for a Allison 250-B15G is 0.697 to 0.706, which works out to be about 10 gal/hr. So on takeoff you are burning about 30 gal an hour. The sales ad says 20 gph, which sounds like a good average. So why turbines. Well it weighs 180 lbs and makes 317 hp. Similar later models weigh about 200 lbs make 420 HP! Nuff said. BUT there's more.
Also the turbine has altitude capability. It looses less HP with altitude and is effect by the cooler temps to a great degree. So the above SM 1019 (Basically a Cessna Bird Dog Liaison plane) has a FL250 service ceiling. That is the Joy of the turbine, not fuel burn. The joy is also reliability. Once you start getting into the 350-400 hp range turbines, they start to look good. What does a 450 HP Pistons engine look like. Joe private pilot in the lower HP ranges, say below 300 HP, is best served by the good old piston. That is why you don't see commercial small turbines for aircraft propullsion.
Lycoming makes 400-450 HP engines like the TIGO541, IO720 and IGSO540. They get pretty complicated and heavy, so the turbine premium $$ starts to pay its way onto aircraft commercial aircraft. After 450 HP forget it, piston engines are starting to get large, expensive and rare. I know some one will chime in about some aluminum block V8 or falconer V12 experimental engines. True, love'em but not cheap or small or light. Why don't we see the sky filled with V8's?
Cost: Turbine parts can cost $xx,xxx for one turbine stage? If you do a hot section and have a turbine or burner problem, its going to hurt. The good news is parts should go 6000 hours. TBO of the compressor, burner, gear box, fuel controller (HMU) and governor is either on condition or 2000-3500 hours. Hot section inspection is 1750 hours. Some turbine parts are life limited at 3000-6000 hours. So its not maintenance free. You can imagine what component inspections and an overhaul might cost.
Innodyn claims some amazing maintenance periods. Here is a large company like Allison, which has about 167 million hours on 29,000 units of the Allison 250 engines from 317hp to 650hp, talking about 3000 hour TBO's and Life limited parts of 6000 hours. Innodyn claims 5000 hours TBO, about 2000 better than the Allison.
This is a real turbine and about as small as you will find in a plane from the factory. Turbines really start to make sense when you get in to 600 to 1000 hp.
Than with the new turbo fans, cost and fuel burn are even less. With out the mess of a prop, the jet is the way to go. Anyone want to make a jet RV? Kidding,
George
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gmcjetpilot
Well Known Member
How about under the plane
RV8-J markII
(note: P&W F100-PW-220 @ 23,000 lbs thrust, giving a TWR of 6 to 1, but some airframe beef up might be required. Sustained vertical maneuvers will be possible.)
You could just sling it under the fuselage and extend the gear for ground clearance. The cowl could be turned into a baggage compartment or extra fuel tank which you would need. G (and yes i don't know photo-shop well)rv8ch said:Sure - just hang the pods out there like on a ME262.
RV8-J markII
(note: P&W F100-PW-220 @ 23,000 lbs thrust, giving a TWR of 6 to 1, but some airframe beef up might be required. Sustained vertical maneuvers will be possible.)
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Takeoff checklist for RV8-J markII:
- Increase thrust to brake limit (approx 2%)
- Release brakes
- Set takeoff thrust
- Rotate and climb at Vy or 80 degrees pitch, whichever the plane desires most
- Inhale deeply
- Call 3000 feet
- Call FL100
- Call FL180, entering class A
- Call FL600, leaving class A
- Re-inhale as needed
- Call ballistic
- Declare fuel emergency
Whiskey Charlie
Well Known Member
brianwallis
VAF moderator
Rich of peak
HEY!!!!!! Please run 100 rich of peak...unless you have every cylinder monitered and I would still run 100 degrees rich of peak... unless you like paying for jugs....
I could be wrong...
Brian
Rick of Austin said:
HEY!!!!!! Please run 100 rich of peak...unless you have every cylinder monitered and I would still run 100 degrees rich of peak... unless you like paying for jugs....
I could be wrong...
Brian
Innodyn Fuel Burn
According to Innodyn's FAQ page, fuel burn is 7 gallons per 100 HP. My calculation shows that using a 255 HP turbine X 70% power X 7 gph/100HP = 12.5 gph, less that the IO-540! (255 X .7 X .07 = 12.5)
They also recently announced the arrival of a dyno to test their turbine.
According to Innodyn's FAQ page, fuel burn is 7 gallons per 100 HP. My calculation shows that using a 255 HP turbine X 70% power X 7 gph/100HP = 12.5 gph, less that the IO-540! (255 X .7 X .07 = 12.5)
They also recently announced the arrival of a dyno to test their turbine.
gmcjetpilot
Well Known Member
Hummm Hummm Hummm
Yes that is highly dubious and has been their claim for years. If they could achieve this P&W, GE, RR, manufactures of turbines would be beating a path to their door for partnership if these SFC where true.bob321c said:
I was just trying to give an apples to apples comparison to a IO-540 at 70%. You would more likely cruise at 90% power on the Innodyn turbine with a fuel flow of 16 gph. But at a higher cruise speed than the Lycoming since it can't cruise at 90%. More power equals more fuel with any engine.
cjensen
Well Known Member
I love the Innodyn idea, but the fuel burn claims have yet to be validated. I understand your comparison, but the Innodyn won't run at 70%. It's a direct spooled turbine that is spinning at 60,000rpm or whatever ALL THE TIME. Idleing on the "T", taxiing, takeoff, cruise, landing...The only thing that changes is the prop pitch. 255 horsepower equals about 18gph all the time.
ddurakovich
Well Known Member
I've been under the same impression, so I decided to look at the numbers for a Piper Meridian, and, amazingly, they look to be very close to that 7 GPH per 100 HP!gmcjetpilot said:
Now, that includes a full power climb to FL300, and max cruise thereafter. Looking at some other data on the PT6 family, it looks like fuel consumption goes up 50% when flying at FL200 vs FL300, and I would guess it would increase substantially more at 10,000 feet?
George???
I would absolutely love to see some innovative new technology present itself to the experimental community, and losing 100#'s of engine weight reduces the number I have to lose (OK, in the interest of good health, I should go ahead and lose them anyway!), but I'm afraid there is too little real data, at specified conditions that most of us fly at, to get enthused yet......
Too bad!
