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Another Diesel!

Would be nice to see even a ballpark price estimate. I like the turbonormalizing and FADEC control, though this part was a little concerning:

The weight is equivalent to a typical Lycoming 0-360 engine plus 34 kilos.

That's a 75lb weight hit up front. I can stand to lose a few pounds off my person, but that would be taking it a bit too far.

I wonder how much a non-turbo version would weigh?
 
On the other hand, if you believe the 40-45% fuel savings by volume (and are willing to operate at typical Lyc HP settings), an RV7 with 42 gal capacity (252 lbs avgas) could carry only 25.2 gal of diesel/jet-A at 176 lbs. Pretty close to a wash on weight, it could be a lot faster at altitude (given the right airframe), and farm diesel is a LOT cheaper than avgas.

On another note: Interesting motor mount. I wonder if the mount has to go back with the engine when it goes for overhaul....

Charlie
 
Ross,
Have you followed the sube diesel introduction? I spent some time reading up about the motor when it was first posted here. Found some comentary about teething problems with the crank ( or support of ). Just curious if you had any insight. Conceptually, I like the new sube deisel.
 
Ross,
Have you followed the sube diesel introduction? I spent some time reading up about the motor when it was first posted here. Found some comentary about teething problems with the crank ( or support of ). Just curious if you had any insight. Conceptually, I like the new sube deisel.

The early EE20s had numerous crank failures. Depending on who you believe, Fuji redesigned the crank circa 2010MY and the problems went away- or not. I saw photos of the OE crank and it was completely scary looking for a diesel, thin throws and almost no pin overlap. I don't see how they could fix it without a redesign of the entire engine but what do I know?

In light of this, I seriously doubt if the engine above uses the OE Sube crank since that's a 2L engine and nobody would likely rate a 2L diesel for aircraft use at 240hp for TO if they expected longevity.

I know there were some secret billet aftermarket EJ blocks being produced in Europe and there are already many trick parts produced by people like Cosworth. Maybe this company has taken some of that stuff and put it together into into a diesel design or it could all be clean sheet. I'd speculate that it is maybe a 2.3-2.5L.

There are so many new engines coming out now, especially from Europe. I think people are seeing profit possibilities at the $24K-$35K mark on 100-200hp engines. That seems to be the going price range. With CNC and some OTS parts, you can build an engine in small quantities and turn a profit if done right.

Turbos and superchargers don't make sense on what is likely a relatively low altitude engine, just more weight, cost and complexity IMO. Sounds like they are a ways off from proving it all in flight for any meaningful amount of time.
 
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Don't hold your breath.

Anyone wonder why Textron are sending back all the C182 diesels and retrofitting them with IO540's? I have have a few ideas where and why and not all are limited to the engine.

Turbo-diesel aero engines are really a problem in my mind, their critical altitude and relight issues are something that many do not seem to think about, although the FAA no doubt do.

The extra weight is a major problem and the supposed fuel savings are only minor compared to the cost of the installation.

On the other hand, if you believe the 40-45% fuel savings by volume

I underlined the obvious point. So has anyone seen a light weight turbo diesel with a BSFC of around 0.217 anywhere? Because my IO540 is pretty darned good at just about 0.395 and to get those kind of numbers you must be comparing the diesel which is a LOP machine with a full rich Lycoming. And that is cheating with numbers.

I would not go changing your RV build on the basis of this press release.
 
Don't hold your breath.

Anyone wonder why Textron are sending back all the C182 diesels and retrofitting them with IO540's? I have have a few ideas where and why and not all are limited to the engine.

Turbo-diesel aero engines are really a problem in my mind, their critical altitude and relight issues are something that many do not seem to think about, although the FAA no doubt do.

The extra weight is a major problem and the supposed fuel savings are only minor compared to the cost of the installation.



I underlined the obvious point. So has anyone seen a light weight turbo diesel with a BSFC of around 0.217 anywhere? Because my IO540 is pretty darned good at just about 0.395 and to get those kind of numbers you must be comparing the diesel which is a LOP machine with a full rich Lycoming. And that is cheating with numbers.

I would not go changing your RV build on the basis of this press release.

Couldn't have said it better. Until they prove it in real life, it's only a curiosity.

Makes good sense where Avgas is $8-$12/ Gal or not available, other than that, not so much given the usual high up front price.
 
The early EE20s had numerous crank failures. Depending on who you believe, Fuji redesigned the crank circa 2010MY and the problems went away- or not. I saw photos of the OE crank and it was completely scary looking for a diesel, thin throws and almost no pin overlap. I don't see how they could fix it without a redesign of the entire engine but what do I know?

Agree completely. They were super thin for an SI engine.
 
Thielert went bankrupt after a great effort to enter the market with certified engines, that about says it all.

Diesel works well in ships, big trucks and some autos but it won't make it in aviation. There are other choices that work quite well and have for some time.

War always spurs technical development and there was an effort to make diesel engines work during WWII but nothing came of it.

The economic climate is not favorable to diesel, never has been, I do not understand why this dead horse is pursued.
 
Thielert went bankrupt after a great effort to enter the market with certified engines, that about says it all.

Diesel works well in ships, big trucks and some autos but it won't make it in aviation. There are other choices that work quite well and have for some time.

War always spurs technical development and there was an effort to make diesel engines work during WWII but nothing came of it.

The economic climate is not favorable to diesel, never has been, I do not understand why this dead horse is pursued.

I think it makes great sense where avgas is expensive or unavailable, like Europe, Africa etc. The initial acquisition costs where fuel prices are similar, usually negates any fuel burn advantages though in the long term if you look a borrowing costs.

The Austro AE300 diesel has been pretty successful and reliable from the get go. The Thielert (now under new name and ownership) is now also reliable by most accounts. The SMA has had many issues for quite some time and it seems they are not all solved yet. BTW, these two engines are looking at BSFC figures of around .33-.35 in cruise.

I think it CAN make sense if you have a good design.

There are some clean sheet designs coming out. Some will make a positive market impact and some won't. I think you'll see more diesels in aircraft in the future but it's been a hard lesson for many developing the technology. It's important to look at the total picture before deciding this is of real benefit for one's mission.
 
dead horse?

Thielert went bankrupt after a great effort to enter the market with certified engines, that about says it all.

Diesel works well in ships, big trucks and some autos but it won't make it in aviation. There are other choices that work quite well and have for some time.

War always spurs technical development and there was an effort to make diesel engines work during WWII but nothing came of it.

The economic climate is not favorable to diesel, never has been, I do not understand why this dead horse is pursued.

This "dead horse" is pursued because diesels actually work really well in airplanes. Have you flown one? I now have almost 700 hours flying diesels (RV9 with Wilksch diesel and a Sportsman with Continental diesel), and both have been pure pleasure to fly. I suggest you fly one before making statements like this. Did you read any of the articles about the Diesel Sportsman? In this month's (June 2015) Kitplanes, there is an article comparing a diesel Sportsman with a 180 hp Lyc. Sportsman. The diesel stacks up pretty well.

Cessna, Piper, Diamond, Mooney, Glasair, Robin, Redhawk, and others all consider the "dead horse" of diesel worth pursuing. I know of at least 3 aircraft that are being designed and certified around the Continental diesel.

I could go on and on (actually I have!) about the advantages of diesels, but until you've flown one, you really won't understand...

Kurt Goodfellow
RV9 WAM diesel 500 hours
Sportsman CD155 180 hours
 
I'm with Kurt on this

Diesel makes too much sense not to try and develop. Just cause the technology isn't there doesn't mean we should just give up on it. It makes way to much sense. My opinion.

Randy
8A
 
Clearly there is interest and a market for aero diesels. One look at all the OEMs starting to offer these options shows there is a future for these powerplants.

The past should be a strong lesson to their developers as I said before, not all diesel designs have been ready for prime time when introduced even after certification.

Cessna has offered or planned to offer diesel powerplants in their products several times now but had to back pedal when things went wrong. It happened again this month: http://www.aopa.org/News-and-Video/All-News/2015/May/14/Cessna-not-accepting-182-JT-A-orders.

This is not an easy task. Altitude performance and relight can be issues along with the higher weight and cost.

The manufacturers will evolve the engines and tackle the performance and reliability issues I believe. When they do, we'll see a lot more flying, especially in places where avgas is expensive or hard to find.

I was thinking of this new design's use of supercharger and turbo, this might be to improve altitude relight performance actually.
 
Diesel makes too much sense not to try and develop. Just cause the technology isn't there doesn't mean we should just give up on it. It makes way to much sense. My opinion.

Randy
8A

The technology is there... The problem is that it takes awhile to build confidence in the marketplace, and the market is relatively small. I think we're starting to see some real strides towards acceptance of diesels, at least with the Continental.

Kurt
 
Clearly there is interest and a market for aero diesels. One look at all the OEMs starting to offer these options shows there is a future for these powerplants.

The past should be a strong lesson to their developers as I said before, not all diesel designs have been ready for prime time when introduced even after certification.

Cessna has offered or planned to offer diesel powerplants in their products several times now but had to back pedal when things went wrong. It happened again this month: http://www.aopa.org/News-and-Video/All-News/2015/May/14/Cessna-not-accepting-182-JT-A-orders.

This is not an easy task. Altitude performance and relight can be issues along with the higher weight and cost.

The manufacturers will evolve the engines and tackle the performance and reliability issues I believe. When they do, we'll see a lot more flying, especially in places where avgas is expensive or hard to find.

I was thinking of this new design's use of supercharger and turbo, this might be to improve altitude relight performance actually.

It'll be interesting to hear more about the CKT. With it being a 4-stroke, I don't understand the need for a supercharger and turbo, when the Turbo should do the job. Glasair flew their Sportsman to OSH at 17,500' with no problem, and I suspect many Diamond DA42 drivers do the same thing, or even higher... The Continental just has a single turbo.

I really not sure what I'm talking about here, but it seems like the SMA diesels (Cessna 182 JT-A) have been plagued with problems relating to cold temps (STC'd 182's needed winterization kits to help keep the engine warm in winter). The SMA is air cooled, while the rest of the diesels I'm aware of are liquid cooled. There are many Cessna 172's out there with Continental diesels, and Cessna is still moving forward with the Skyhawk JT-A. This leads me to believe that liquid cooling might be the better way to go. I've certainly had no problems with the liquid cooling systems in either of my diesels. I've had absolutely no problems restarting either of my engines when forgetting to switch tanks at altitude. Of course I have not tried it up in the flight levels... That's not where I fly.

This must be very frustrating for Cessna; I'm sure they would not have made such a big push with the C182 JT-A if they did not feel like it was a solid, reliable product. Of course, the FAA often has other ideas...

Kurt
 
It'll be interesting to hear more about the CKT. With it being a 4-stroke, I don't understand the need for a supercharger and turbo, when the Turbo should do the job. Glasair flew their Sportsman to OSH at 17,500' with no problem, and I suspect many Diamond DA42 drivers do the same thing, or even higher... The Continental just has a single turbo.

I really not sure what I'm talking about here, but it seems like the SMA diesels (Cessna 182 JT-A) have been plagued with problems relating to cold temps (STC'd 182's needed winterization kits to help keep the engine warm in winter). The SMA is air cooled, while the rest of the diesels I'm aware of are liquid cooled. There are many Cessna 172's out there with Continental diesels, and Cessna is still moving forward with the Skyhawk JT-A. This leads me to believe that liquid cooling might be the better way to go. I've certainly had no problems with the liquid cooling systems in either of my diesels. I've had absolutely no problems restarting either of my engines when forgetting to switch tanks at altitude. Of course I have not tried it up in the flight levels... That's not where I fly.

This must be very frustrating for Cessna; I'm sure they would not have made such a big push with the C182 JT-A if they did not feel like it was a solid, reliable product. Of course, the FAA often has other ideas...

Kurt

The SMA, when fitted to various Cessnas under an STC had widespread issues with case fretting and many were replaced under warranty.

There were also serious altitude and temperature limits on them originally making them essentially flat land and warm climate engines only. Much of this was to do with the very high boost pressures (80 inches roughly)required to make the power and thus limited by the pressure ratio the turbo could develop up high plus they would not relight above 8 to 10,000 feet reportedly. Other people said the fuel pre-heating was insufficient but not sure how true that was.

Anyway, in service experience was not that great on the original engines.

SMA/ Conti has apparently fixed the altitude issues (new turbo which failed unfortunately leading to a forced landing) and the restarting with new glow plug setups and hopefully the case fretting as well. They will get it all solved eventually I believe, however progress in fixing these rather serious issues was slow under SMA, the engine has been out there for over a decade, not impressive considering the design team pedigree and resources available compared to what WAM did IMO.

The supercharger on this latest design would provide some boost pressure on a windmilling engine, perhaps extending the relight zone upwards, assuming the engine/ prop will windmill with the high CR and the gearbox here. Otherwise it's just a waste IMO. Staged turbos would be lighter and more efficient if they need better altitude performance.
 
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So what do you guys think about the opposed piston two stroke Gemini? This configuration has worked very well for Fairbanks Morse. The small physical dimensions and light weight of a common rail injected two stoke diesel may be a good design for small aircraft.
 
So what do you guys think about the opposed piston two stroke Gemini? This configuration has worked very well for Fairbanks Morse. The small physical dimensions and light weight of a common rail injected two stoke diesel may be a good design for small aircraft.

Concept looks good but the proof will be in the pudding after a few get 1000+ hours of flight time without problems. 2 strokes have a better power to weight ratio than 4 strokes but BSFC figures are rarely much better than legacy SI engines running LOP. Again, the big appeal is using Jet or diesel fuel in place of expensive or unavailable avgas IMO. They have the funding now to see it go forward. Will be interesting to see how it turns out in a couple years.
 
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