Alternative Fuels Are Not The Future

Cpt_Kirk

Cpt_Kirk

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Ted Striker
Turboprop > Any piston

I saw an interview displaying a new, smaller turboprop on an RV-10 for GA aircraft. Says they plan on giving it away for $100K with a potential TBO of 3,000 hours. Gas is cheaper. Engines are more reliable, smoother, and easier to operate. We paid $2.32/gallon here in RDU after using a discount card. I think we filled up in FLL for something around $3.30/gallon.

I think it's time to leave piston-powered engines for lawnmowers and move onto something better.

The video link: http://youtu.be/SVpljYHot1o
 
Hopefully this engine will be able to deliver. I'd love to ditch my 520s for turboprops, but fuel consumption must be similar to make it worthwhile. At $100k/pop, it'll be a challenge to convince people to shell out the cash for STCs to convert the legacy fleet outside of the real high-dollar planes.

But I'm very glad to see this.
 
Well, that will turn into minimum a $250k engine when certified, will they continue to have a $110k uncertified one? Even at $110k, that's over 5 times what 250hp costs in a recip. For an experimental recip, for $110k I can build a 350hp Diesel installation and beat his fuel specifics. That's one thing I didn't see addressed was fuel specifics. That is what has always been to primary operational issue with turbines in small planes, you get range limited by fuel.
 
Cpt_Kirk said:
I think it's time to leave piston-powered engines for lawnmowers and move onto something better.
Click to expand...

Couldn't agree more. I was myself so sick of piston engine management, service etc it prompted my switch to a turbine. Just had enough of the rattle and constant babying you have to do.

I hope they succeed to get it certified. It would be a game changer at that price.
 
Henning said:
Well, that will turn into minimum a $250k engine when certified, will they continue to have a $110k uncertified one? Even at $110k, that's over 5 times what 250hp costs in a recip. For an experimental recip, for $110k I can build a 350hp Diesel installation and beat his fuel specifics. That's one thing I didn't see addressed was fuel specifics. That is what has always been to primary operational issue with turbines in small planes, you get range limited by fuel.
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over 5 times?

Factory new Lycoming IO-540's from Vans are $50k a pop. For most guys building RV-10s, another $50k for a turbine is not a big leap.

You're right about the fuel consumption issue, however.
 
Turningfinal said:
over 5 times?

Factory new Lycoming IO-540's from Vans are $50k a pop. For most guys building RV-10s, another $50k for a turbine is not a big leap.

You're right about the fuel consumption issue, however.
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That's certified, I am not restricted to that. I can build and install an aluminum LS Chevy engine in an experimental, and I can buy an Audi TDI with a phenolic block and 600hp as a bobtail for under $20k.

If you want an aircraft engine, look what the 240hp offerings from the aftermarket like ECI cost for their 'Experimental' series engines.
 
And the cost to insure is? If you thought certification was a tech killer wait until we have mandatory GA insurance...:lol:
 
GeorgeC said:
Only 18-36 gph!
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Ok, let's perform a really rough $/hour estimate. Compare that with a current piston out there now with a similar power output.

Jet A w/ Prist- ($4.00 avg (no discount card))
@SL $144/hour
@Cruise $72

You guys can feel free to argue about the final pennies, but I'm not going to get into it. I didn't expect this engine to be a home run right off of the bat, but it sure is a start and a venture I was to see continued.

I probably wouldn't feel so strongly about this if I didn't switch between a PT-6, O-360, IO-360, IO-550, TIO-540 for work. They don't even compare.
 
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Also, think about prop noise and ground pounders around the airport.

PT6-67B/P spins at 1,700 for takeoff.
TP100 spins at 2,150 (I'm assuming at takeoff).

IO-360 on the SkyTrasher was 2,800 on takeoff.
Everything else I use is 2,700.

That in itself is a big improvement.
 
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I'll be interested to see what the price is certified. Is it the same factory in Czech that builds the Walters?
 
looking quickly, the dry weight of the TP100 is 156lbs. A Lyc io540 is about 400lbs or more depending on which version you need. If this is true, thats a lot of weight not on the nose gear.
 
charheep said:
looking quickly, the dry weight of the TP100 is 156lbs. A Lyc io540 is about 400lbs or more depending on which version you need. If this is true, thats a lot of weight not on the nose gear.
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That's also a lot of ballast you have to carry to be able to load the plane in CG, otherwise you have to move the engine forward a few feet to increase its arm.
 
Henning said:
That's also a lot of ballast you have to carry to be able to load the plane in CG, otherwise you have to move the engine forward a few feet to increase its arm.
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Looks pretty good on an RV-10.
 
Cpt_Kirk said:
Looks pretty good on an RV-10.
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What's the load/CG envelope look like? Weight and balance is weight and balance regardless, you have to have weight forward to allow for weight aft, and 27%MAC is what people usually look for.
 
You never saw the Thrushes that got converted from radials?
 
JoseCuervo said:
You never saw the Thrushes that got converted from radials?
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If you're talking to me, hell yes, Ag Cats too, flown both. That engine is way the hell out there, and the load is on CG, not in the luggage compartment.
 
What certified? It's an RV-10. You can strap 10 Briggs engines together and fly that as it's experimental. Unless he's going after the cert GA market, in which case the final price on the engine out the door with prop and governor will be a lot more like $300k. Plane - free, engine - $300k. I didn't read part 33 that he's talking about, is that some restriction on a turbo-shaft/prop engine? I thought the restriction was just on pure jet type?

Glad to see any kind of development in this direction. The price could go down to $100k per if he got an order for 3000 copies. That -- will -- never -- happen -- in -- GA -- market. Nevar....
 
docmirror said:
Glad to see any kind of development in this direction. The price could go down to $100k per if he got an order for 3000 copies. That -- will -- never -- happen -- in -- GA -- market. Nevar....
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Which is unfortunate.
 
docmirror said:
What certified? It's an RV-10. You can strap 10 Briggs engines together and fly that as it's experimental. Unless he's going after the cert GA market, in which case the final price on the engine out the door with prop and governor will be a lot more like $300k. Plane - free, engine - $300k. I didn't read part 33 that he's talking about, is that some restriction on a turbo-shaft/prop engine? I thought the restriction was just on pure jet type?

Glad to see any kind of development in this direction. The price could go down to $100k per if he got an order for 3000 copies. That -- will -- never -- happen -- in -- GA -- market. Nevar....
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If you watch the video, you will hear him state quite clearly that the intended market is certified airplanes. There is a potential in the Cirrus OEM market, especially @350hp if they ever pressurize a cabin.
 
Henning said:
There is a potential in the Cirrus OEM market, especially @350hp if they ever pressurize a cabin.
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That would be awesome, but I doubt they would want to make the SR22 come close to the performance of the Jet they are building.
 
Back 10 or so years ago there was an outfit that was promoting their 200ish HP turbine for the experimental market. Even had one mounted on an RV-8 at Oshkosh that had flown at least once.

A couple of years later, they were nowhere to be found.
 
CJones said:
Back 10 or so years ago there was an outfit that was promoting their 200ish HP turbine for the experimental market. Even had one mounted on an RV-8 at Oshkosh that had flown at least once.

A couple of years later, they were nowhere to be found.
Click to expand...

Uploaded in 2006 and is an RV-4, but was it similar?

http://youtu.be/tsRLFXirq4o
 
Be a nice alternative ,if it works out,depends on the certified price. Think Diesel engines might also work out,jet A is the future.
 
Cpt_Kirk said:
Turboprop > Any piston

I saw an interview displaying a new, smaller turboprop on an RV-10 for GA aircraft. Says they plan on giving it away for $100K with a potential TBO of 3,000 hours. Gas is cheaper. Engines are more reliable, smoother, and easier to operate. We paid $2.32/gallon here in RDU after using a discount card. I think we filled up in FLL for something around $3.30/gallon.

I think it's time to leave piston-powered engines for lawnmowers and move onto something better.

The video link: http://youtu.be/SVpljYHot1o
Click to expand...


I flew just over three hours this weekend with 500 pounds in the cabin and started with 288 pounds of fuel burning roughly 23 gallons of 87 octane ethanol-free gas that was about $2.58 a gallon. I'm slow covering only about 320 miles but still. That's about $0.18 a mile with an engine an prop that only costs about $19k to replace.
 
CJones said:
Back 10 or so years ago there was an outfit that was promoting their 200ish HP turbine for the experimental market. Even had one mounted on an RV-8 at Oshkosh that had flown at least once.

A couple of years later, they were nowhere to be found.
Click to expand...

I reme er that RV-8. One of the reasons I have one. :D

Never did see it again though.
 
Turbines will never make it big in small fixed wing GA, the just aren't optimized for the job. Between initial and fuel costs, it just isn't something that can be justified except in very special circumstances.
 
Henning said:
Turbines will never make it big in small fixed wing GA, the just aren't optimized for the job. Between initial and fuel costs, it just isn't something that can be justified except in very special circumstances.
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Never say never. I'd like to be more optimistic.
 
Cpt_Kirk said:
Never say never. I'd like to be more optimistic.
Click to expand...

Where I see the potential for turbines is in the electromotive source for heavier quad and hex copters, that is where the power to weight ratio really comes in, and with an electromotive drive, the engine can always operate at peak efficiency RPM.

In fixed wing GA applications, the cost structrure vs. typical incomes just won't allow for it. Cheap turbines are not efficient, efficient turbines are not cheap. It's the nature of the physics that they will not be as thermally efficient as a recip, and then when you have the engine that is priced more than the same plane flying with a recip, your market of potential buyers becomes seriously restricted.

This isn't a new concept, people have been sticking small APU turbines in small planes for decades, you can get and support them cheap, and it never seems to work out, because the reality of the GA market is it is already in general operating at the very peak of it's financial capability. Look what happened to the market in the last collapse. The entire market dropped, even old fully depreciated planes. Old 172s always sold around $40k before 2007 all the way back to when I started flying in the beginning of the 90s, same for the old Cherokee 140s. They were the bench mark planes for the bottom of the GA ownership market, that was the price of entry. Now half the fleet goes for that. $170k Bonanzas now sell below $100k in the same condition.

Typical fixed wing GA will never go to turbine, the value just does not exist no matter how much simpler it makes life.
 
Henning said:
That's certified, I am not restricted to that. I can build and install an aluminum LS Chevy engine in an experimental, and I can buy an Audi TDI with a phenolic block and 600hp as a bobtail for under $20k.

If you want an aircraft engine, look what the 240hp offerings from the aftermarket like ECI cost for their 'Experimental' series engines.
Click to expand...

No, that's not certified. That's a factory new experimental XIO-540.

The ECI/Titan is $45k.

New IO-540s are not cheap.

You can compare Subies or Mazdas or LS-1s or whatever you want, but for 95%+ of RV-10 builders the IO-540 is the engine of choice.
 
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stratobee said:
Couldn't agree more. I was myself so sick of piston engine management, service etc it prompted my switch to a turbine. Just had enough of the rattle and constant babying you have to do.

I hope they succeed to get it certified. It would be a game changer at that price.
Click to expand...

Assuming you bought a Commander as you were discussing, there's also a huge speed bump.
 
Turningfinal said:
No, that's not certified. That's a factory new experimental XIO-540.

The ECI/Titan is $45k.

New IO-540s are not cheap.

You can compare Subies or Mazdas or LS-1s or whatever you want, but for 95%+ of RV-10 builders the IO-540 is the engine of choice.
Click to expand...

How many will double their engine cost and reduce their fuel economy? I bet you find more Chevies than turbines on RV-10s.
 
The other aspect of the cert process has to do with the scale of cost per HP. Lets say there is a min dollar amount to cert any turbo-shaft engine - call it $5 mil as an estimate. So, it doesn't matter what shaft HP you design, your base line starts at $5 mil. Now, double the HP from 240 up to 480 and what is the non-linear added cost to cert the 480HP? Surely it's not $10 mil, so there's a certain amount of scale economy at work. Which I why I think there are no cert small Ga turboshaft engines out there. By the time you get into the cert process, you might as well make it 600-1200SHP and be done with it. Buyers in that market have bucks to spend. The garage guy building his RV-10 or Lancair might balk at a $300k powerplant where a piston for $75k is doable.
 
docmirror said:
The other aspect of the cert process has to do with the scale of cost per HP. Lets say there is a min dollar amount to cert any turbo-shaft engine - call it $5 mil as an estimate. So, it doesn't matter what shaft HP you design, your base line starts at $5 mil. Now, double the HP from 240 up to 480 and what is the non-linear added cost to cert the 480HP? Surely it's not $10 mil, so there's a certain amount of scale economy at work. Which I why I think there are no cert small Ga turboshaft engines out there. By the time you get into the cert process, you might as well make it 600-1200SHP and be done with it. Buyers in that market have bucks to spend. The garage guy building his RV-10 or Lancair might balk at a $300k powerplant where a piston for $75k is doable.
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Exactly, turbines are most definitely "economy of scale" engines, the larger/higher out put, the more efficient it becomes. Small outputs are just not economical.
 
Aren't there barriers to entry for the market other than just the cost?

As I understand it, the altitude 'sweet spot' for smaller turbines is in the mid-upper teens. Most GA aircraft that are designed to use the 250-350hp engines aren't operating an airframe designed to operate at those altitudes - lack of pressurization, cabin heating systems, speed limitations on the airframe design (flutter), etc.. So even if the price point for a 250-350hp turbine got down to comparable to a piston single, would the market adopt the new engine if they aren't able to realize the true benefits of efficiency of the turbine?
 
stratobee said:
Couldn't agree more. I was myself so sick of piston engine management, service etc it prompted my switch to a turbine. Just had enough of the rattle and constant babying you have to do.

I hope they succeed to get it certified. It would be a game changer at that price.
Click to expand...

It wouldn't be a game changer at that price because that price is at least double what a piston engine costs. Well that and this...

Henning said:
Well, that will turn into minimum a $250k engine when certified, will they continue to have a $110k uncertified one? Even at $110k, that's over 5 times what 250hp costs in a recip. For an experimental recip, for $110k I can build a 350hp Diesel installation and beat his fuel specifics. That's one thing I didn't see addressed was fuel specifics. That is what has always been to primary operational issue with turbines in small planes, you get range limited by fuel.
Click to expand...

I once knew a guy, back in about 1998, who was building a two-seat turboprop with (IIRC) about 150 to 200 hp. He was building it at Hearne Municipal Airport in Hearne, TX. At the time I ceased basing at that airport he had successfully high-speed taxied it.

This is just more aviation pie-in-the-sky hype that will soon come crashing down to FAA cert reality.

I think diesel engines may be the next thing in piston airplane engines. But even those are far more complex than the 1930s technology we fly now.
 
CJones said:
Aren't there barriers to entry for the market other than just the cost?

As I understand it, the altitude 'sweet spot' for smaller turbines is in the mid-upper teens. Most GA aircraft that are designed to use the 250-350hp engines aren't operating an airframe designed to operate at those altitudes - lack of pressurization, cabin heating systems, speed limitations on the airframe design (flutter), etc.. So even if the price point for a 250-350hp turbine got down to comparable to a piston single, would the market adopt the new engine if they aren't able to realize the true benefits of efficiency of the turbine?
Click to expand...

That is most certainly a factor. The Bull Thrush with an 1820 used a lot less fuel than it's 1200hp turbine counterpart.
 
Cpt_Kirk said:
Turboprop > Any piston

I saw an interview displaying a new, smaller turboprop on an RV-10 for GA aircraft. Says they plan on giving it away for $100K with a potential TBO of 3,000 hours. Gas is cheaper. Engines are more reliable, smoother, and easier to operate. We paid $2.32/gallon here in RDU after using a discount card. I think we filled up in FLL for something around $3.30/gallon.
Click to expand...

Right now, I have 280hp and burn 12gph at cruise. Where I buy fuel, I currently get it for $3.99/gal so about $48/hour in fuel costs in cruise. I can also taxi out, climb to altitude, and fly for 7 hours to dry tanks.

Same field, I could buy Jet-A for $2.99/gal. That's $54/hr at the low end, and I'd lose 2.4 hours worth of endurance.

My IO-550 is turbine-smooth at climb and cruise power.

Where's the upside again? I'd love it if they could succeed, but I just don't see it happening. Hell, the diesel conversions aren't selling particularly well and they offer improved fuel economy.

Sadly, this market is shrinking every year and I just don't see a lot of new engine developments succeeding due to the costs of certification.
 
Cpt_Kirk said:
Also, think about prop noise and ground pounders around the airport.

PT6-67B/P spins at 1,700 for takeoff.
TP100 spins at 2,150 (I'm assuming at takeoff).

IO-360 on the SkyTrasher was 2,800 on takeoff.
Everything else I use is 2,700.

That in itself is a big improvement.
Click to expand...

You're missing part of the equation: The radius of the prop. Larger props have to turn at lower RPMS to keep from going transonic, and it's really the tip speed that's causing prop noise, not the RPM. For example, if you took that same PT6-67B/P and spun it at 2700 RPM, it'd sound like you were tearing the sky apart even though it's running at the exact same RPM as many light GA singles. If you took an IO-360 and spun it at 1700 RPM it'd be significantly quieter than the PT6.
 
flyingcheesehead said:
Right now, I have 280hp and burn 12gph at cruise. Where I buy fuel, I currently get it for $3.99/gal so about $48/hour in fuel costs in cruise. I can also taxi out, climb to altitude, and fly for 7 hours to dry tanks.

Same field, I could buy Jet-A for $2.99/gal. That's $54/hr at the low end, and I'd lose 2.4 hours worth of endurance.

My IO-550 is turbine-smooth at climb and cruise power.

Where's the upside again? I'd love it if they could succeed, but I just don't see it happening. Hell, the diesel conversions aren't selling particularly well and they offer improved fuel economy.

Sadly, this market is shrinking every year and I just don't see a lot of new engine developments succeeding due to the costs of certification.
Click to expand...

That is the advantage to recip at low altitude. At cruise you aren't making 280hp on 12gph, you are making 200hp, this is where the advantage to recips comes in. They are just hunky dorey operating at reduced power, turbines aren't, so you can't reduce power to match aerodynamic efficiency for the altitude. If you want to get to an efficient TAS, you have to climb to where the airframe efficiency matches the power output.
 
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