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Price-point for SMA 305 or Continental 230

jeffwhip

Well Known Member
I thought I'd start a thread and generate a discussion here regarding the diesel engines being produced by SMA and Continental.

I'm cheering for Scott F. to finish his fly-off so we can get some more RV-10 performance information with a diesel engine, but I suspect either of these engines are going to cost more than what I can get an IO540 through Vans ($47,400).

At what price-point do you think it would make sense to buy either of these engines? How much would you be willing to spend to get one with the added benefits?
 
I know many may not agree with me, but the price for the diesel would need to match a Lycoming TIO540 if you want an apples-to-apples comparison. I have no idea what a new Turbo 540 costs, but I imagine it will be pushing $80-90k? Anyone out there know?

I would be willing to pay $60-75K for a 230-260 hp turbodiesel for my next project. Again, I know most folks think I'm nuts, but I have now flown over 900 hours in two diesel EAB aircraft, and I really enjoy the benefits of Jet-A piston power. I've outlined those benefits elsewhere on VAF for years...

Kurt Goodfellow
RV9 WAM diesel 560 hrs
Sportsman CD155 diesel 384 hrs.
 
I thought I'd start a thread and generate a discussion here regarding the diesel engines being produced by SMA and Continental.

I'm cheering for Scott F. to finish his fly-off so we can get some more RV-10 performance information with a diesel engine, but I suspect either of these engines are going to cost more than what I can get an IO540 through Vans ($47,400).

At what price-point do you think it would make sense to buy either of these engines? How much would you be willing to spend to get one with the added benefits?

It's good to see Conti and Scott take the leap into the diesel / Experimental market together.

I wouldn't assume just yet however that the SMA/ Conti diesel is ready for prime time and will go to TBO with minimal maintenance. They've had a long and chequered past to date. Why not wait a few years until a bunch prove they can go the distance first?

A slightly warmed over atmo 540 will make 280ish hp and motivate an RV10 quite well for quite a bit less than this engine is likely to sell for. Running LOP with modern EFI and EI, the fuel flow difference isn't that much and unleaded avgas looks to be just around the corner now which will allow a bit more fuel efficiency still.

At current fuel prices and realistic fuel flows, you're going to save something like $16/hr. A $25K initial cost difference would take 1500 hours to pay back through fuel cost savings (not including the cost of that initial outlay which could be invested). Resale value may not be enhanced either.

If Conti can get the price down to $55-$60K or so, it starts to look a lot more promising, assuming the old problems are solved and it lasts as expected.

As Kurt says though, it does not boil down to straight $ for everyone. Some people just want it/ like it and that's reason enough for many to do it. I have no problem with that. People should build and fly what they want.
 
I am trying to think through this right now. The best comparable engine right now to compare it to is the new Lycoming ie2 which is a twin turbo 350 HP variant that lists for $115,000.

I'm going to have to run some numbers but if I could get an engine that was basically a FADEC with no fuel mixture and save $1/gal as well as burn about 3 gal/hr less...at what point would it be worth it? My best guess is that I would save $15/hr in fuel costs alone.

Of course I'd have to factor in all of the additional costs to make it work in the RV-10. And I wonder how much would it cost to rebuild this engine in the future?
 
Price is only part of the story

There will be other differences to consider, petrol burns diesel bangs, airframe engine propeller combinations. Extra engineering time during build = a lot of extra effort.
I'm not knocking it just pointing out, would love to see a viable diesel alternative.

Rob
 
I am trying to think through this right now. The best comparable engine right now to compare it to is the new Lycoming ie2 which is a twin turbo 350 HP variant that lists for $115,000.

I'm going to have to run some numbers but if I could get an engine that was basically a FADEC with no fuel mixture and save $1/gal as well as burn about 3 gal/hr less...at what point would it be worth it? My best guess is that I would save $15/hr in fuel costs alone.

Of course I'd have to factor in all of the additional costs to make it work in the RV-10. And I wonder how much would it cost to rebuild this engine in the future?

I'm not understanding why you would be comparing a 350hp engine to a 230hp one? You can fit an existing 540 with 9 to 1 pistons and EFI/EI for around $56K, make 280+hp and have mostly automatic mixture control with fuel burn running LOP, within 8-10% of a diesel. This engine will outperform the SMA to about 7000 feet. It will fit with no mods in the aircraft and you have many propeller choices.
 
Brand me as one of those guys who would LOVE to fly behind a diesel. I switched my tractors from gas to diesel and have never looked back. I just like diesels.

BUT... Ross's pragmatic statements above really bear close scrutiny. One has to really want a diesel in order to sway the decision in favor of engines which don't have a very strong track record. Ross's experience with alternative engines has earned him a reputation as a cautious experimenter who doesn't throw his weight behind a design until it works very well indeed. As such I really appreciate his taking the time to share his wisdom here.

I have read many of Kurt's posts on both his WAM diesel RV and his CD155-powered Sportsman. As a Sportsman builder I have watched his posts with enthusiasm and I'm very glad to see he has racked up nearly 400 hours on that aircraft. Still, I would have real difficulty schmoozing the CD155 past my wife as I just don't think I could make a strong enough case for the numbers. The only saving grace might be better fuel availability in the far north. So far she hasn't caught northern fever so I don't think I could make much hay with that. I guess I'll be living with our O-360 Lyc for a while yet...
 
I'm not understanding why you would be comparing a 350hp engine to a 230hp one? You can fit an existing 540 with 9 to 1 pistons and EFI/EI for around $56K, make 280+hp and have mostly automatic mixture control with fuel burn running LOP, within 8-10% of a diesel. This engine will outperform the SMA to about 7000 feet. It will fit with no mods in the aircraft and you have many propeller choices.

Ross,
It sounds as though you are well respected here so I'd love to hear from you further. The only reason why was comparing SMA's diesel to the new Lycoming is because they are similar technology. To be specific, I'm referring to SMA' s new engine they just announced will be on the Diamond 5 seat a/c next year...SMA SR305-260E. This is the 260 HP version.

Obviously the SMA engine puts out 260 HP and has one turbo while the new Lycoming puts out 350 HP and comes with two turbos. Perhaps a better comparison would be to a TIO-540. Does anyone know how much those cost?
 
Another engine option is to have a Barrett or Aerosport build you one from a core. Should work out about 10% cheaper on a apples to apples basis, plus you can have it built the way you want it and get (arguably) a better engine and better warranty to boot.

A couple of cautions that I would have with any engine choice and the RV10 are looking at too much horsepower and too much heat to dissipate.
The airplane has gobs of power as it is. Lightly loaded the airplane can already cruise near the yellow band which makes descent planning touchy to bring the thing down without inefficiently pulling the power way back to stay at a safe speed.
I would also be concerned about heat management with a turbo. Having flown through two Arizona summers, heat management is already a handful and could be much worse with a turbo residing in the cowl. Engine cowl design melds competing/conflicting sciences of trying to be aerodynamic and yet properly dissipating heat. I'm not an engineer but I imagine that the sweet spot is pretty narrow and squeezing the balloon on one side will expand it on the other.
There used to be a factory in Brazil that was building complete RV10's equipped with Turbos. It would be interesting to know how that worked out for them.
 
I don't see a big need for an angle valve or turbo 540 in most RV10s to compare to a 230 or 260hp SMA/ Conti. You're already into the yellow arc with a stock 260hp 540.

As I said, 9 to 1 pistons, a little port matching and good induction system with decent sized throttle body and proper exhaust system will give you at least 280hp on a PV 540. That gives you very good TO, ROC and cruise already. Why add the weight, complexity and cost of a turbo/AV engine? The comments about cooling are very valid with added hp and especially turbos at altitude- likely to need additional cowling mods to do it right.

The diesel needs to be turbocharged because they would be pathetic in the hp department without one. The SMA runs massive manifold pressures to make 230hp already- I believe something like 90 inches for TO power.

In the end though, I believe the show stopper will be the price for most folks who are thinking diesel.
 
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But...

Barrett built my engine. Dual EFII, Cold air induction, 9:1, Superior cylinders, EFII billet rocker covers, Reiff preheat, B&C starter, alternator, standby alternator.

Ran 290 HP on the dyno.

Cost was slightly more than a box stock engine from Van's, which seems to be the best price around...

Just a data point.
 
I don't see a big need for an angle valve or turbo 540 in most RV10s to compare to a 230 or 260hp SMA/ Conti. You're already into the yellow arc with a stock 260hp 540.

As I said, 9 to 1 pistons, a little port matching and good induction system with decent sized throttle body and proper exhaust system will give you at least 280hp on a PV 540. That gives you very good TO, ROC and cruise already. Why add the weight, complexity and cost of a turbo/AV engine? The comments about cooling are very valid with added hp and especially turbos at altitude- likely to need additional cowling mods to do it right.

The diesel needs to be turbocharged because they would be pathetic in the hp department without one. The SMA runs massive manifold pressures to make 230hp already- I believe something like 70+ inches for TO power.

In the end though, I believe the show stopper will be the price for most folks who are thinking diesel.

Ross,
The draw to me is the ability to burn Jet A and not 100LL and we all know that Jet A is much less flammable.

The SMA engine produces an incredible amount of torque, making a 3 blade prop a necessity. It seems to me this aircraft would have a great climb rate all the way up to 12,500 MSL and then power the engine back to 55% power (143 HP) and enjoy the fuel savings.

I'm at the stage in my build where I need to decide on an engine pretty soon so that I know how to finish building it out. I've never owned an RV-10 so I'm trying to educate myself and ask a lot of questions. I have a tremendous amount of respect for anyone who has already build an RV-10 and I'm here to learn from you all.

I agree with you that the IO540 is the proven path. If I go that route, I'll probably have Barrett build my engine also. However, if our society only stayed on the proven path, we'd still be flying bi-planes.

I'm very interested in either Continental's engine or the SMA but will only take the plunge if the risks are manageable and the price is right. As always, I appreciate everyone's feedback.
 
Good discussion. However, if you are getting relatively close to engine purchase time you need to honest with yourself on a couple of points:

1. Do you want to be an early adopter and live with all of the potential birthing pains? IOW do you want to fly or spend your time as an experimenter troubleshooting issues?
2. How important is country-wide AOG maintenance to you?
3. Does your desire to burn JetA outweigh the price premium for this engine?

There are no right or wrong answers, just please go in with your eyes open and any emotion checked at the door.
 
I'm following this with great interest. While lurking, and doing paper evaluations on a number of things I was quite interested in putting a diesel engine in my airplane. As I continue to read and see how things are progressing, I'm not 100% sure what I'm going to do when I get to the point of installing my engine. I also have a lot to learn about all the different options (even if going with a 540!).


If there is a decision to change to use a different engine, realistically when does that decision need to be made? I'm sure you need to have this in mind before you do the FWF and possibly as you are working on the Fuselage.
Does the choice of engine require you to make changes to the Wings or Empennage?
(Sorry if this is a dumb question)
 
Ross,
The draw to me is the ability to burn Jet A and not 100LL and we all know that Jet A is much less flammable.

The SMA engine produces an incredible amount of torque, making a 3 blade prop a necessity. It seems to me this aircraft would have a great climb rate all the way up to 12,500 MSL and then power the engine back to 55% power (143 HP) and enjoy the fuel savings.

I'm at the stage in my build where I need to decide on an engine pretty soon so that I know how to finish building it out. I've never owned an RV-10 so I'm trying to educate myself and ask a lot of questions. I have a tremendous amount of respect for anyone who has already build an RV-10 and I'm here to learn from you all.

I agree with you that the IO540 is the proven path. If I go that route, I'll probably have Barrett build my engine also. However, if our society only stayed on the proven path, we'd still be flying bi-planes.

I'm very interested in either Continental's engine or the SMA but will only take the plunge if the risks are manageable and the price is right. As always, I appreciate everyone's feedback.

Certainly burning Jet fuel is attractive to a number of people, just remember that lots of small airports don't have it.

The flammability part, true it's lower than avgas but if you get a line rupture in a crash at thousands of psi on a red hot turbo, it's gonna burn for sure. Jet airplanes burn very well as we've all seen before.

The Lycoming produces pretty much the same amount of torque and more hp. Hp quantifies the amount of work an engine can do, not torque.

I'd look carefully at the cold weather/altitude limitations on relight and general operation. I know that they have improved those on this engine since it came out, but before, this was a warm climate only engine.

I agree, if nobody takes the step to try something different, we'll still be flying the same stuff in a few years as today.

When will Continental make the engine available to other builders if the RV10 install and flight testing is successful? Price? I doubt if anybody knows right now.
 
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I don't have a -10 but I do have a certified plane with a similar-sized engine, and I'm building an RV-3B with a Lycoming O-320. I worked my way through college by building a BD-5 for a fellow which never, thankfully, got its engine, thus sparing its owner's life.

My take on it is that while the specs might sound appealing, they ALWAYS do when a new replacement engine is under development, no matter by who. What really matters, once the basics of weight and power and size and fuel usage are acceptable, is reliability and serviceability. Since the RV-10 is a people-hauler, reliability is a very, very important objective, and frankly, I would not want to be the first kid on the block with a newly-released engine. And I certainly wouldn't want the people I love to fly in something whose reliability hasn't been demonstrated.

Let's not forget that we need more than an engine: we need a fully-developed and tested installation. Without that, it's merely someone's dream.

1. I'd want some actual flight experience by a good number of real builders, not just the factory's people, who have had a chance to report their experiences, including weight and balance, fuel and oil usage as well as reliability,

2. A fully-developed FWF kit, including prop, that real builders have installed and written about that, and that you can cost out and compare to the standard one, including ease of installation,

3. Enough engines that have flown to TBO and been overhauled, with some idea of that impact in terms of downtime and money,

4. A stable-enough company that we feel comfortable with to make spares available and support the inevitable teething issues into the future,

5. And optionally, some people who built and flew the plane with the engine, put several hours on it, and sold the plane and demonstrated market acceptance of it used.

Without these, this is blue sky dreaming and ought to be in the "Alternative Engines" section, in my own opinion. There, we can debate the merits, if any, of the thing.

Dave
 
I'm following this with great interest. While lurking, and doing paper evaluations on a number of things I was quite interested in putting a diesel engine in my airplane. As I continue to read and see how things are progressing, I'm not 100% sure what I'm going to do when I get to the point of installing my engine. I also have a lot to learn about all the different options (even if going with a 540!).


If there is a decision to change to use a different engine, realistically when does that decision need to be made? I'm sure you need to have this in mind before you do the FWF and possibly as you are working on the Fuselage.
Does the choice of engine require you to make changes to the Wings or Empennage?
(Sorry if this is a dumb question)


Brian,
Not a dumb question at all. I have the quickbuild wings so all I need to do is close out the bottom skins after I get everything installed inside the wings. Here is the big picture as I see it. I want to build my RV-10 the right way and I don't want to be out of the CG envelope during certain flight regimes (1, 2, 3 or 4 people with varying fuel weights). Now factor in a diesel engine which is heavier...but by how much exactly?

The engine I choose will dictate which battery I buy and where I ultimately place the battery box. I may need to situate other items in the tail as well to compensate for the CG.

I believe the Continental engine requires the RV-10's fuel system to be a specific way so that means as long as this motor is a possibility, I can't run my fuel lines. I currently have all my control surfaces complete and have the tail cone attached to the fuselage. I'm at that point where I need to get my engine and avionics nailed down so I know how to proceed.

As others have pointed out, we still don't know the exact weight of either of these engines (Continental or SMA) with everything attached nor the price. And since weight is a definite factor, there is a difference in weight between the 2 & 3 blade aluminum and composite props.

My time is valuable, so the last thing I want to do is build it one way and redo my work later. I'm sure some of this is inevitable, but I'd like to get it done right the first time. So, I'm trying to educate myself as much as possible now while I can. I'm also going to Oshkosh this year where I hope to get most of my questions answered. Hope this helps.
 
The OP (Jeff) simply wanted to know what people would be willing to pay for a viable diesel engine for an RV-10. As usual, this has quickly turned into a "forget about a diesel! Lycoming traditional engine is best!" thread.

Yes, it might be best to move this thread to Alternative Engines, but we're talking about certified aircraft engines, made by well-known aircraft engine manufacturers (especially in the case of Continental), many thousand of flight hours (the SMA), and millions of flight hours (other Continental diesels).

If we all sit around and wait for someone else to fly these engines to TBO or TBR, how are we ever going to enjoy better technology and greater safety and fuel savings? There are those who are willing to take a reasonable, informed risk in order to be pioneers, and there are some (probably most) who are perfectly content to let "the other guys" prove the technology. I believe this thread is aimed at the pioneer group. I don't think we need to hear over and over again how much better a Lycoming is. I think we already know about that.

Kurt Goodfellow
 
The OP (Jeff) simply wanted to know what people would be willing to pay for a viable diesel engine for an RV-10. As usual, this has quickly turned into a "forget about a diesel! Lycoming traditional engine is best!" thread.

Yes, it might be best to move this thread to Alternative Engines, but we're talking about certified aircraft engines, made by well-known aircraft engine manufacturers (especially in the case of Continental), many thousand of flight hours (the SMA), and millions of flight hours (other Continental diesels).

If we all sit around and wait for someone else to fly these engines to TBO or TBR, how are we ever going to enjoy better technology and greater safety and fuel savings? There are those who are willing to take a reasonable, informed risk in order to be pioneers, and there are some (probably most) who are perfectly content to let "the other guys" prove the technology. I believe this thread is aimed at the pioneer group. I don't think we need to hear over and over again how much better a Lycoming is. I think we already know about that.

Kurt Goodfellow

People should know the story, history, good points, bad points before making a decision. It comes down what you the buyer, is willing to pay and whether you are willing to accept the potential further financial and possible reliability risks of a relatively unproven engine package. This engine does not have anywhere near the flight time the Conti 155 diesel does plus it's an entirely different design so no parallels for reliability should be drawn there.

Historically, light diesel aero engines have had a poor reliability/ cost record on introduction, even the certified ones. It took many years to work out a lot of these issues on most of them. The exception has been the Austro AE-300.

As of 2008 (10 years after introduction) SMA had only about 50 engines in service, mostly on STC'd Cessna 182s (engine cost $75K), most in Europe and Africa where avgas was expensive or hard to find. Initially, most users were happy but then reports started to trickle in that there were systemic crankcase fretting issues and engines were often being removed and returned with as little as 400 hours on them. One fellow flying these in Africa for a Missionary Group told me they were nice to fly but the engines didn't last long before leaking oil and making metal. One at our airport was a hangar queen, having had at least 2 engine changes that I know of with hardly any hours on it.

In 2009, an AD was issued on SMA 182s to change the intercooler and more closely inspect clamps and induction hose connections after several failures. (remember this engine runs 90 inches MAP for takeoff). This has been a problem area on other aero diesels as well. High induction temps at the intercooler inlet and high pressures mean things have to be done right here. Lose an induction hose and you lose as much as 75% power.

I think the "E" model was introduced in 2009ish and certified in 2011 to address various problems but it was one of these which suffered a turbocharger failure and a forced landing on a factory 182 test article in 2013. Cessna was on/off /on/off with the 182 diesel project and pulled the plug in 2015. There were other similar occurrences which were not well publicized. SMA was never very transparent with issues. Remember, this basic engine had already been certified for 15 years. The following article covers some of the story and mystery about the lack information:

https://generalaviationnews.com/2015/08/30/tracking-down-answers-at-oshkosh/

The latest engines require a turbocharger replacement at 1200 hours, halfway to TBO last I heard. The turbos are working very hard at these pressure ratios (around 3-3.5) so their longevity may not be so good.

Apparently some propellers are also not so happy with the power pulses of this engine which is another concern with the entire package. I'd hope that Continental has directed a lot of testing at that aspect too.

I am guessing that Continental has devoted considerable time and technical resources to fixing all known issues with this engine in the last few years but considering the very limited number flying, they were still having issues as little as 2 years ago. Maybe all is well now in 2017 but I think we lack enough flight hours so far on the latest iteration to have a good confidence level.

SMA and Continental of late, should have pounded a bunch of these engines at MCP years ago, both in a test cell and development aircraft to uncover these design issues before market introduction. That in itself is worrying and does little to inspire confidence, along with their reluctance to tell the true story. It's ok to stay quiet in the development stage where failures are expected and part of the process to work out the bugs. But staying quiet after the engine is certified and in service does your reputation no favors.

I am happy to see this RV10 flying with the 230E under the guidance of Continental. It's the first step to more widespread release and use of the engine in Experimentals. There is certainly a market for it as we see a lot of interest in aero diesel threads here and on other forums. I wish them success after the hard road they've negotiated.

Of note also is that Soloy will now be doing STC'd SMA installations on 182s this year so the design seems to be gaining some new traction now.

Power to you if you feel comfortable being a pioneer here but as with any alternative engine you should simply go into the decision making process knowing the history and with eyes wide open. It may not be all roses as some of us have found out the hard way...

Here's a photo inside this engine which may interest gearheads (lower right of page): https://www.smaengines.com/our-product/sr305-230er
 
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Ross,

I appreciate your openness in this thread. IF I go this route, I definitely want to go in informed. Regarding Diamond's recent press release where they pick the 260HP version of the SMA engine, do you think Diamond's engineers would have thoroughly combed through this engine?

It seems to me having SMA's engineers along with Diamond's engineers vetting this engine, is a good thing. In the end weight, reliability and cost will be major factors for me.
 
Ross,

I appreciate your openness in this thread. IF I go this route, I definitely want to go in informed. Regarding Diamond's recent press release where they pick the 260HP version of the SMA engine, do you think Diamond's engineers would have thoroughly combed through this engine?

It seems to me having SMA's engineers along with Diamond's engineers vetting this engine, is a good thing. In the end weight, reliability and cost will be major factors for me.

Yes, after Diamond's debacle with the original Thielert diesel, I believe they'd have learned their lesson this time around and done lots of their own testing. This development plus that of Soloy is probably a sign most of the problems may have been licked. It seems as of late 2016 that the improved version has a new lease on life with these new users-17 years after initial certification...
 
If we all sit around and wait for someone else to fly these engines to TBO or TBR, how are we ever going to enjoy better technology and greater safety and fuel savings? There are those who are willing to take a reasonable, informed risk in order to be pioneers, and there are some (probably most) who are perfectly content to let "the other guys" prove the technology. I believe this thread is aimed at the pioneer group. I don't think we need to hear over and over again how much better a Lycoming is. I think we already know about that.

Kurt Goodfellow

I couldn't say it better. Folks, this is the great thing about experimental aviation. Build the plane you want to fly. Want to tinker and be on the leading edge? Do it! Want to just fly and stick with proven components, fine!

My 10 will be luxurious, probably a little heavy, have no mags, and have A/C! Gasp!!! I don't fault others for no interioir and steam gauges because that's what they want.

I for one am very interested in new engine technologies such as this. If prices stay near or slightly above a very nicely built 540, I'll seriously consider it. I'm thinking $50-75K range.
 
Jeff,

If you say you would be happy at 55% power, with a stock IO540 that would be 9.59USG/hr. How much less burn do you need?

Next is to consider the Cessna 182 drama. They are very tight lipped about it although I do know what the failures were and why......no engineering solution to it as mountains are usually above 1000'. I am curious as to how the CD230 goes. Watching with interest the -10 thread. Long way to go yet.

Then there is weight and cooling drag issues.

Barrett's or Powermasters in Tulsa OK would be worth talking to.
 
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Jeff,
Can and would you share what you know the 'problems were' with the C182 development with respect to the diesel?

I've followed it for a long time but I've heard very little since they cancelled the program when the last C182 landed unintentionally landed someplace they weren't planning on.

Paul
 
The story I pieced together from several sources was this....

Off airport landing because of turbocharger bearing failure- bearing manufacturer failed to follow manufacturing specs.

FAA became very DIFFICULT during remaining certification attempt.

Upper management decided after additional 1.5 yrs of testing to cancel project.

This is the condensed version, but you get the point.
 
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