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RV-10 with Continental CD-230 Diesel

Kurt, just so others know diesel fuels have paraffins, and at some temperature will gel just like candle wax and become difficult to impossible to pump. It is called cloud point and standardized as part of the on/off highway diesel fuel standards. Typically it is around 8 Deg F for summer fuels. It will plug filters and the engine will reduce power and stop. Some high pressure fuel systems cool with fuel and are inefficient, so return-to-tank temps are elevated and will affect the OAT offset. JP-4 JP8 and Jet A all have quite low cloud points.

So, Kurt, did you do anything special to identify cloud point for cold weather operation? How do you deal with that? Does your RV/Sportsman have a thermocouple in the tank to monitor the temps, or add some additive (like gasoline) to lower the CP?

Thanks for posting, it is good to hear from a person experienced with aero diesels. I was hesitant to mix the non-road fuels here, but the cost effectiveness is excellent at this time.

Bill, you're right about this. I live in the west where I can run diesel most of the year to save a few bucks. But in the cold, you'd have to be careful. I run Jet A mostly, just because I feel safer knowing it comes from a clean source. I would think Mogas users should have the same concern... Jet A doesn't gel until -30C or so, which is never a problem for me. IN colder temps, Prist is added to Jet A to protect it further from gelling. My tanks do have fuel temp sensors, just to make sure the fuel's not too hot or cold (it's mostly the higher temps that Cont is concerned about). The return fuel is pretty warm, but i've never even come close to the hot limits and I'm flying out of Vegas. Just remember you're running the same fuel as the jets and turboprops, and they don't have freezing problems...

I was only making the $$ savings case for non-taxed fuel to provide a valid comparison for the Mogas argument. I still think it's safer to stick with a proven fuel from a proven source.
Kurt
 
Perhaps we could get some informative information.

Kurt, what sort of diesel do you have in your RV-9? What is the empty weight? What is the actual fuel burn at what speed and altitude? Do you have more or less climb performance? What experience have you had with the manufacturer in terms of installation and ongoing support?

Your Sportsman went together under a supervised build program at Glasair. We don't currently have that option with an RV. IF Continental allowed it, how would you rate the installation process, assuming you had to engineer it yourself? Note that the current thinking from the executive suite is that it would be too difficult for general release. Would you agree?

Dan,
My RV9 has a Wilksh WAM 120 in it. This was the first plane I've ever built. Empty weight is just under 1000 lb with paint. Weight without paint was 974 lb. The April 2010 Kitplanes article tells a fairly accurate story about the performance. Ken Krueger and I tested my '9 against the Van's RV9A. It was not apples to apples, but there was no argument that the plane performed just as an o-235 - powered RV9 would. Climb to 11000' was avg just under 800 FPM. Ongoing support from Wilksch has been stellar. I could not ask for better support. They were very supportive during installation 10 years ago as well.

With regard to the Sportsman: I think with a reasonable FWF kit, it would not be too difficult for a builder to install the CD155. I actually did design and fabricate my own FWF for the CD155. I helped Glasair with their first one; I did the FWF part for them, and they helped me with the firewall aft wiring. This was required because initially we were using Cessna 172 retrofit kits and there were adaptations to be made firewall aft. FWF was a new ballgame as the Sportsman has a lot less space to work with. It was a fun project; Glasair was wonderful to work with.

If you recall from the article from Osh, Rhet Ross said that CMI would be offering the air/oil cooled CD230 to EAB first, and then work into the liquid cooled engines. They want to make sure they're doing this right, and I don't blame them.
Kurt
 
I was looking at this a few days ago. It's interesting to compare the 360 Lycoming to the the 155hp diesel in the Glastar:

http://www.glasairaviation.com/sportsman-specs.html

http://www.kitplanes.com/issues/31_11/flight_reports/diesel_sportsman_21111-1.html

Highlights:

Diesel 133 KTAS on 7.3 GPH (48.6 PPH), Empty 1560 lbs.
Lyc O-360 134 KTAS on 8.5 GPH (51 PPH) (@65%) Empty 1350 lbs.

Takeoff and initial climb is better with the Lycoming. Above about 5000 feet the turbo diesel is better.

FF cost on the diesel (including prop) $90K. Intro price was $60K.

Note the O-360 has a carb and mags and we know with modern engine controls we can do at least 10% better than this running LOP which would make the cruise fuel consumption nearly a wash.

Ross,
Your information is somewhat outdated. I'm not sure why Glasair has not updated their performance info. Their current info must be based on initial projections. But If you'll look at Kitplanes June 2015 (comparing my Sportsman to a 180 hp Sportsman, by Ken Krueger), the actual test shows the diesel at 130KTAS burning 6.1 gph, and the gas at 129KTAS burning 11.4 gph, with a projected LOP fuel burn of 8.2 gph. Of course, that was only in cruise. In climb, the gas Sportsman burned a LOT more fuel. At lower altitudes, the diesel still burns much less, but the speeds not quite as good because the diesel has less HP. Lucky for me, I don't cruise much below 5000'. To quote Ken Krueger: "The CD155 consumes anywhere from half to three fourths (depending upon leaning technique and altitude) as much fuel as the Lycoming O-360 at the same power output".

The $90K cost point is way out of line. I am not speaking for Glasair or anyone else, but price you show was based on purchasing the 172 kit, which we used initially. From that kit I would say we ended up throwing away $30K worth of parts that wouldn't adapt to the Sportsman. Now Glasair, after producing more Diesel Sportsmans (Sportsmen??), can order just what they need from Continental. You can't fault them for trying to recoup some of their initial development costs, but my guess is, you can negotiate a much better price now. And that should only get better with time. They've also managed to pull a fair amount of weight out of the installation. Also, you need to remember that the cost includes FWF kit, engine, MT CS 3 blade prop, governor, redundant electronics, engine monitoring, etc. On any kit plane, those items add up pretty quickly, especially if they're FAA certified (hey, my Phase 1 was 15 hours shorter; I saved a few bucks there!:))

My son and I just spent a few days flying backcountry strips in Idaho along with other Sportsman owners, and there was no perceptible difference between our plane and theirs, performance-wise, except ours used significantly less fuel. It was not, and never is "nearly a wash".

I just want to make people aware that the diesel thing is coming, and it's much better than a lot of folks imagine. I don't want to be redundant, but the simplicity of operation is incredible. It is SO nice to just start it up like a car, set the power where you want it, and forget about it. No fussing with the mixture as you climb, cruise, descend. No messing with the prop (at least on the CD155), no carb ice worries, no hot-start cold-start issues. No priming. No worries about shock cooling. Its a pretty good gig.
Kurt
 
Kurt, thanks for posting some great real world information. I too dread the usual response to anything "experimental" on here that often follows any new ideas besides the Lycoming option. Not saying that the Turbine Ten is quite economical yet, but it's still cool seeing new things.

I think the option is up to the mission. For long cross country flying like some folks do, the diesel seems to be pretty awesome. I'll certainly stay tuned to the first flying example!
 
Petrol burn or Diesel Bang

My 2p questions.

Wonder what the vibration frequencies, prop frequencies (therefore selection), airframe frequency differences will be once the wheels leave the ground and the dampening mass changes.

Rob
 
Kurt, I just provided the links for people to read themselves and did say that a $30,000 discount was being offered subsequently.

We have many customers flying Lycomings with properly optimized EFI and EI control these days and they are not burning anywhere near what you quote here, especially at altitude running LOP where these things really make a difference over carbs and mags. With zero GAMI spread and being able to advance timing for optimal PCP, these old engines can do amazing things.

As Dave Anders found in flight testing- 6.8GPH at 200 mph TAS at around 16 to 1 AFR. The BSFC is very close to diesel territory here and this case is still not at best AFR for the lowest BSFC which occurs around 18 to 1 where we can now run smoothly with these controls- demonstrated to 200F LOP.

Some are running their Lycomings LOP even in the climb once they are above 5000 MSL or so. The mixture control has become a way to limit % power at or near WOT and people are seeing over 20% reductions in fuel burn from climbing ROP.

It's best to compare to engines with the latest technology (SI EFI/EI to diesel FADECS) using optimized running techniques.

Of course with EFI/EI we also don't have any more issues with carb ice, hot or cold starting, priming etc. Comparing a Lyc. with a carb and mags, using poor technique, doesn't present a level playing field IMO. The days of these devices on experimental aircraft is rapidly drawing to a close.
 
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Kurt, are they many Wilksch diesels flying in North America? Has yours been reliable? It seems like a practical choice for those who want to try a diesel, while Continental seems ****-bent on dictating package installations on some unknown timetable.
 
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Kurt, are they many Wilksch diesels flying in North America? Has yours been reliable? It seems like a practical choice for those who want to try a diesel, while Continental seems ****-bent on dictating package installations on some unknown timetable.

Dan, As far as I know, I'm the only one flying the Wilksch in the US. Indus Aviation had a Thorp with a WAM engine, but I the whole Indus thing is shut down for now. There are 20 or more WAM 120's flying worldwide, and the factory is doing a good job of supporting us. My engine has been perfectly reliable; it has never let me down, never missed a beat in the 509 hours I've flown it.

I agree with you, the WAM might be the best diesel for EAB. It is by far the simplest, and while it's not as simple to install as a Lycoming (Lycomings are not necessarily simple to install, but they are a "known" thing) but they are much less complex than a Continental diesel. The problem is that for now there is just not enough of a market for Wilksch to produce a decent sized batch of Gen II 167 hp 4 cyl engines, or 3 cyl engines. What Wilksch needs is a solid customer to order a decent production run, such as a drone manufacturer. I have stayed in regular contact with the majority owner and they are completely ready to go, but without an "anchor" customer or investor, he's just not willing to invest a sizable sum to manufacture a large batch of engines. As so many in this forum have indicated, the money's here in the States, and there's just not enough interest here, since good old Lycomings are reasonably priced, reliable, and known. Avgas is reasonably priced so there's just not a great incentive to go diesel here. The rest of the world would love it, but the worldwide EAB market is just not that big. Of course, if the WAM were certified, the market potential would be larger, but it cost even more $$$ to certify it. The way I see it, Wilksch is caught between the proverbial rock and hard place. I know they are exploring options, hoping to find a way to get into production. If anyone out there has any ideas, I'd be happy to present them. I would commit to purchasing at least 4-5 engines if they were to become available. I would love to build another Sportsman with the 167 hp 4 cyl engine and see how it stacks up against the CD155 and O-360. I would put another in my RV9. I have friends who would also love to purchase these engines. Any ideas out there? From what I've been told, in order to produce a reasonable batch, the 167 hp engines would need to fetch $40K or so. Not an easy pill to swallow here in the US.

Kurt
 
Kurt

Thanks for posting and glad to hear of your solid success.

I was looking around in Oshkosh this year and there was no sign of the WAM diesel or maybe I just missed it.
Your diesel engine does sound like one I would install despite the elevated cost compared to the gas burners.
A solid customer like Van would help a great deal to get this engine into production and make it available in North America.
 
Clearly there is a perceived market. Both Continental and Superior purchased significant diesel programs, plus there are serious clean sheet start-ups like EPS. Right now, that market isn't North America, unless the players bring prices into line with avgas engines.

If I were the primary investor at Wilksch, I'd try to cut a deal with Lycoming.
 
A solid customer like Van would help a great deal to get this engine into production and make it available in North America.

You might be right but as I alluded to previously, there has to be a significant market to make it happen.
There may be some customers that are willing to pay a high premium for a diesel engine installation, when the payback in reduced fuel burn and cost per gallon will not come close to making up the difference in engine cost, but that number is likely very small. From a business standpoint, that would make a big investment in developing an installation, a bad decision.

Until something happens in the U.S. (avgas fuel prices go through the roof, etc) it just doesn't make sense if a large portion of the market has good access to 100LL (or its future equiv.) at a price that competes with the cost of diesel/jetA and the premium paid for the diesel engine installation.

I realize there are places in the world that diesel fuel is much lower cost than avgas. The problem is it is a very small portion of the overall world market and would not generate enough sales to offset the development costs.
 
Kurt, you're active in the WAM diesel community, so can you save some search time for me? Two questions.

I recall the loss of Steve's RV-9...

https://assets.publishing.service.gov.uk/media/5422eea0e5274a1314000213/Vans_RV-9A__G-CDCD_04-14.pdf

..in which the accident report acknowledges two possible causes, fuel contamination and sheared camshaft bolts. Wilksch picked fuel, despite bent valves indicating that the engine was rotating when the bolts sheared. The pilot also reported the engine windmilling during the descent, which says there was no compression, further indicating that the valves were bent long before the prop contacted the ground. Was there more information later?

I also seem to recall someone's engine going back to Wilksch with cylinder issues. If it wasn't yours, whose was it?
 
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Kurt, you're active in the WAM diesel community, so can you save some search time for me? Two questions.

I recall the loss of Steve's RV-9...

https://assets.publishing.service.gov.uk/media/5422eea0e5274a1314000213/Vans_RV-9A__G-CDCD_04-14.pdf

..in which the accident report acknowledges two possible causes, fuel contamination and sheared camshaft bolts. Wilksch picked fuel, despite bent valves indicating that the engine was rotating when the bolts sheared. The pilot also reported the engine windmilling during the descent, which says there was no compression, further indicating that the valves were bent long before the prop contacted the ground. Was there more information later?

I also seem to recall someone's engine going back to Wilksch with cylinder issues. If it wasn't yours, whose was it?

Dan,
I'm familiar with many of the WAM owners, but have not been really active in the past couple of years while I've been focused on the Sportsman. I am familiar with Steve's lost RV9A, and was under the impression that it was a fuel issue, especially since the engine stoppage occurred just after switching tanks. I have inadvertently ran mine out of fuel once, and I can say two things: 1. The engine windmills just fine. 2. It restarts very quickly once the fuel selector is moved to a tank that contains fuel! (BTW, the same is true for the CD155) I had not seen the accident report; that was interesting to read. In 2009, I complied with the timing gear bolt SB, and there is a continuing SB to check the torque on the bolts, which I've done regularly and never seen a problem. It's very easy to do, simply requiring the removal of the alternator, which drives directly from a cush drive on the back of the crank (the timing gear is sandwiched between the drive and the crank).

You'll note that in my posts I've maintained that the WAM engine has performed flawlessly, because it has, but it has not been without issues. As I've mentioned before, there have been a few SB's that require regular attention, the most notable being the pre-combustion chambers, which are replaced at 50 hour intervals with oil changes. It takes me about 2.5 hours to do it. There was another one-time SB, which included new low-pressure fuel lines. The only other two SB's are the continuing inspection of the cam gear (easy, because it is exposed when the oil sump is removed for pre-combustion chamber maintenance), and the checking of the torque on the aforementioned timing gear bolts. I have had zero issues with these items.

The cylinder issue you mention was mine. Over the past year it seemed like the engine was getting harder to start. Once running, it ran exactly as it had since it was new; no significant oil consumption, same MAP, same fuel burn, etc. So a friend and I checked the compressions and cylinders 2 and 3 were low. So, after flying it 20-30 hours with no issues other than longer starts, I had some time, so I sent the engine back to the factory and they found scored liners in those two cylinders, along with stuck rings. They replaced them, and now it starts perfectly and runs as good as ever. None of the other engines have had this problem. We went over all engine logger data and could find no reason for it. I had never overheated it; oil pressure has always been good. Anyway, since the WAM is a sleeved rebuildable engine, it was just a matter of installing new rings, sleeves. Now my son is flying the plane and it seems even smoother than before.

The only other issue I've had was the front crankshaft seal leaking (my own fault for trying to tie the crankcase breather into the exhaust). Interestingly, it's one of the only "traditional" parts on the engine; it's a Lycoming-style seal. I replaced it the same way as anyone would, with a new one from Aircraft Spruce, and it has not leaked since.

With the Gen II engines, the issues mentioned above have reportedly been corrected, along with some changes to simplify production.

Hopefully this info is helpful.

Kurt
 
I had not seen the accident report; that was interesting to read.

Indeed. As you know, it wasn't the first crank bolt failure; this one had the updated ARP bolts from the third SB on the problem. Even so, the report states "They were recovered and sent for metallurgical examination, which found that all the fractures bore the characteristics of high-cycle fatigue cracks."

The fatigue failure theory is compelling, in particular when viewed in the light of an SB dated August 2012, which required replacing the "crank centre", a part sandwiched between the gear and the crank, and stoning away the fretting damage on the crank stub.

http://wilksch.net/images/Crank Gear Centre Replacement.pdf

The 50 hr inspection of the cam gear is related; they're mandating it because, as stated in that SB, they suspect torsional issues in the geartrain.

The contaminated fuel was taken from the fuel filter/separator, not the injection pump or high pressure lines. We can drain water and grunge from every diesel filter/separator on earth. That's what they do, remove water and dirt before it can reach (and ruin) the injection pump.

As I've mentioned before, there have been a few SB's that require regular attention, the most notable being the pre-combustion chambers, which are replaced at 50 hour intervals with oil changes. It takes me about 2.5 hours to do it.

What does each new chamber cost? How much for the tool kit?

SB here:

http://wilksch.net/images/Pre-Chamber removal & installation guide19.7.10.pdf

The cylinder issue you mention was mine....I sent the engine back to the factory and they found scored liners in those two cylinders, along with stuck rings....since the WAM is a sleeved rebuildable engine, it was just a matter of installing new rings, sleeves.

But it wasn't a problem.

Hopefully this info is helpful.

It is, because now we're discussing reality. With only 20 or so engines out there, it would be a miracle of engineering if they were problem free. "100% wonderful" just doesn't pass the smell test.
 
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Dan,

At my last purchase, the pre-chambers cost 555 British pounds, up from 448 earlier (for the set). I do not remember what the tool kit cost. This is why we WAM owners have been so anxiously awaiting the new Gen II engine. The cost of the chambers is killing us.

I don't recall ever saying that the WAM has been "100% wonderful". I have said that it has run very well, which it has. It has never missed a beat. This forum has not been a friendly place to share info about alternative engines, but I have PM'd all the gritty details to anyone who has cared enough to ask.

As Ive said before, I like the way Wilksch has treated me and others. They've never made outrageous claims about performance, weight, etc. They've been conservative and honest about everything they've done as far as I'm concerned.

Kurt
 
It's interesting how the aviation press has treated the aero diesel introductions- SMA, Thielert, WAM. Glowing reviews of low fuel burn and how they will change aviation. Never any scrutiny about how many test/ flight hours on them before release or even a review of reliability after a couple years in general service.

In all 3 cases above, each development team had extensive backgrounds in the racing engine world right up to Formula 1. You'd have thought that designing and perfecting a low output aero diesel would be childs play.

Turns out, it wasn't. SMA had serious issues with crankcase fretting and most early engines had to be removed at the 200-400 hour mark to be replaced.

Thielert had issues with the pistons and rings going south at 300-500 hours, the engines having to be removed after the oil consumption exceeded the allowed spec. They also had serious issues with the reduction gear clutches, eventually requiring costly removal and inspection every 300 hours. https://www.bea.aero/etudes/thielert.tae125.engines/thielert.tae125.engines.pdf

Now with Kurt's info on the WAM, we see similar, relatively high cost maintenance procedures having to be applied due to design issues.

All these companies had access to test cells and with their racing engine experience one would think they would test these engines to death (literally) before production release as is common with all auto OEMs today. Renault Sport developing the SMA surely had massive technical capabilities at their disposal. One wonders what kind of testing they did not to uncover some of the later problems. 150 hour minimum FAA test?

As a minimum, each should have had one engine on the test cell running every day from idle to max rpm to uncover any TV issues and another running at MCP right to projected TBO.

In each case, it took 5-15 years after release to get most of the bugs worked out while customers were left holding the bag. There were never any true cost savings on a per hour basis as the manufacturers postulated and the aviation press continued to put forth, especially considering the higher initial costs of the SMA and Thielert.

Cessna has had some stillborn attempts to introduce diesel power to their line, a fairly recent attempt ended with an engine failure and forced landing back in 2013 and the program was delayed considerably. http://www.flyingmag.com/technique/accidents/engine-failure-deals-setback-diesel-cessna-182-jt

The Austro AE-300 is the only aero diesel which has really gone along well from the start, probably due to the many lessons learned with the Thielert design. This shows it can be done well the first time around with the right team and development/ test program.

15 years after the introduction of some of these engines, they still haven't changed the face of GA powerplants to any significant degree, mainly due to their high costs and less than good real world maintenance costs.

Fuel burn is an important consideration but so is initial cost, reliability and maintenance costs per hour of operation. The first is meaningless if you are going inside the engine every 50-300 hours to screw around with stuff which should have been designed right in the first place. This is 2016 and we don't expect to have to do that on engines costing many tens of thousands of dollars.

While some might consider this unfriendly in some way, it's really just fact if you look at things objectively. Reality bites sometimes. Yes, the newer versions have been improved but they are still much more expensive than legacy SI engines and have some other disadvantages as well.

The lesson here is it may not be the best idea to be the first adopter of any new aero diesel engine. Why not wait a couple years to see what the real world experience is before you put down your money?
 
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Can I laugh now?

I guess I had that coming. Knew that when I posted. Foolish to fly behind something other than a Lycoming.

I wouldn't expect any of you to understand, but the Wilksch thing truly has been a positive experience for me. There's a certain satisfaction associated with pursuing your passion and being a part of pioneering something new and - one would hope - better. Yes, it costs to do that, and I'm grateful that I can afford it.

Kurt
 
Kurt,

I'm glad that you're satisfied with your choice, and I'm glad that there are guys like you who are willing to take a chance to advance the state of the art. You obviously went in with your eyes wide open and have no regrets.

There's "experimental", and then there's experimental. I remember reading posts from a guy who is running another powerplant -- I think it's a Subaru. If I'm remembering right, he's had more than one in-flight engine failures resulting in off-airport landings. He doesn't consider it a big deal; apparently he lives and flies where it's not a great inconvenience to land in a pasture and call for a ride. You've got a Diesel that has a service history that, frankly, would have a Lycoming or Rotax owner jumping up and down with smoke coming out of his ears - but you're happy with it, because it's doing what you want and you feel you're contributing to the cause.

Some people place a very high premium on rock solid reliability and safety. For others the overarching concern is cost; for others it's getting onto the leading edge of technology in one area or the other. I can understand all of those attitudes, and there's something to be learned from each.

Obviously the manufacturers of these alternative engines (Thielert, Eggenfeller, SMA, Wilksch and many others) thought they had a viable and competitive product. Proving or disproving that is done by guys flying behind them in real life; if perfecting the design could be done in a lab we wouldn't have very interesting auto races. I wouldn't be willing to spend a lot of money to be someone's test pilot, but I'm really glad that there are people who are. It's rare that I am tempted to call anyone else's choice "foolish", even if some don't turn out in a way that I'd be happy.
 
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I guess I had that coming. Knew that when I posted. Foolish to fly behind something other than a Lycoming.

I wouldn't expect any of you to understand, but the Wilksch thing truly has been a positive experience for me. There's a certain satisfaction associated with pursuing your passion and being a part of pioneering something new and - one would hope - better. Yes, it costs to do that, and I'm grateful that I can afford it.

Kurt

Nope, not foolish to fly behind something other than Lycoming Kurt. You are flying behind what you like- very important to us gearheads. I think everyone here respects you for your experimental spirit, all your work with aero diesel installations and your race accomplishments. Nobody else here has that kind of experience. You've stated many times it's not about the cost, it's about the experience and people who've simply bolted up a Lycoming to the existing Van's mount will never be able to fully understand that experience. Your mission is not the same as many others here.

I am reasonably happy with my Subaru conversion ($9500 complete FF including the prop)- except for the part where the oil consumption crept up too far and I had to take it apart at 359 hours. I did post the full teardown experience on VAF and my website to show people what I found. Before that, the internals had never been touched, the valve covers had never been off. The rebuild cost $1000 and I am back for a second round to see how things last this time on a Mogas diet instead of 100LL. All this being said, I have no illusions that everybody should fly a Subaru. Most people don't have the skill or patience to go through what I did and the Lycoming is the best choice for them.

The bottom line is that for the masses here, they cannot do what you've done and don't have the skills or patience to do what you are doing now. Additionally, the numbers just don't add up on the balance sheet here in North America at present. With a change in engine and fuel pricing in the future, that may well change.
 
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I guess I had that coming. Knew that when I posted. Foolish to fly behind something other than a Lycoming.

Spare us that nonsense, please. Ross is a dedicated Subaru guy. I have a gold Lindy on the shelf for a Suzuki conversion, and I'd love to have a reliable, cost effective diesel. You're not getting squeezed by Lycoming people. You're getting squeezed by alt-engine fans because you've been sugar coating your diesel experience. We want ALL the information, not just the wonderful stuff. And no, it's not acceptable to restrict the downside to some secret handshake "only-the-worthy" system of distribution.

Everybody here would agree you have the right to experiment with whatever you want, and many of us admire you for it, including me. But brother, please, tell all or tell nothing.
 
Kurt, keep the info coming!!

I guess I had that coming. Knew that when I posted. Foolish to fly behind something other than a Lycoming.

I wouldn't expect any of you to understand, but the Wilksch thing truly has been a positive experience for me. There's a certain satisfaction associated with pursuing your passion and being a part of pioneering something new and - one would hope - better. Yes, it costs to do that, and I'm grateful that I can afford it.

Kurt

Actually, I did not see anything funny. Your experience is supremely valuable, as we all learn "how the sausage is made" in the aero diesel world. The companies that undertaken designs have a huge learning curve. Performance of the aero diesel is 15% of the challenge, if that. Keep the factual information coming, Kurt, and don't worry about the chuckles. I get that from my neighbors about building in my basement! It is not personal, others like me really want to hear about the real world results as opposed to the paper claims. Paper is cheap.

I have been a diesel guy for decades, and in my short stint at Conti, the chief engineer and I spent many hour after work at the chalk board outlining what would have to happen to have a flying diesel. He designed the first (gov contract) diesel with the fork and blade rods. A grand experiment that was pitifully underfunded. To Ross's comments, some of the technology might not be new, but the unseen experience and knowledge of the (mundane to most) development process to validate a diesel design is not widely possessed. If Cat or Cummings undertook the project, they would need to be taught the aero world and although they have experienced staff of thousands of engineers, the outcome might be compromised due to that. What is new is new, and this application is new.

Ross, a simple hydraulic pulsator test would have revealed the case fretting. It is a standard lab validation test for diesel designs. It tests fretting, fatigue, head gaskets and more. This is the first test that should be run to dial in the engineering design and analysis factors.

In case it is not known Cat and Cummins trade off for the most diesel and gas (natural) HP shipped worldwide each year.
 
Wilksch Engines

As I was planning my RV-9A back in 2002 I surveyed the engine scene and of the alternative (to Lyclones) engines the Wilksch WAM series made the most sense. Mark Wilksch's background in aviation and racing and his innovative design skills led to the design of a remarkable family of engines, the 120 hp 3 cylinder WAM 120 and the 160 hp 4 cylinder WAM 160. It was fully integrated with a forward mounted coolant radiator, had low fuel burn, and even back then it seemed like 100LL avgas had a questionable future. I had also followed the Curtis-Wright developments of their diesel aviation Wankel engine which I thought was a perfect airplane engine, but they had abandoned the field some time before.

After I started building in 2004, I contacted Wilksch in early 2005 about their 160 hp four cylinder and was advised "availability of the WAM 160 is planned for the end of 2005". Well here we are 11 years later, Mark Wilksch is no longer with the company he founded, and the WAM 160 is still not available. For me, the Superior IO-320 that's sitting in my living room waiting for installation is the perfect choice. It's readily available, cost effective, and bolts up to the airframe. It's also a great conversation piece while it's in my living room;)

I think the entire discussion of alternative engines (auto derived and/or purpose designed diesel) really underscores the difficulty and engineering required to bring to market a satisfactory and reliable aircraft powerplant. It's obvious that the small size of the aviation market makes a complete test program extremely difficult.

I admire Mark Wilksch and his designs, and Kurt for being an early customer. I look forward to reports on the RV-10 with the Continental CD-230 with anticipation.
 
I guess I had that coming. Knew that when I posted. Foolish to fly behind something other than a Lycoming.

I wouldn't expect any of you to understand, but the Wilksch thing truly has been a positive experience for me. There's a certain satisfaction associated with pursuing your passion and being a part of pioneering something new and - one would hope - better. Yes, it costs to do that, and I'm grateful that I can afford it.

Kurt

Kurt, I hope you have a change of heart....
I don't think anyone means to criticize your decision process. It is experimental after all, so we are all free to do what we want.

The criticism, and the cause of most of the hard feelings between adopters of new technology (whether it be an alternative engine, ignition system, or what ever) an people in forums like VAF, is the glowing reports while hiding anything that might be considered less than ideal.

There is nothing wrong with you being 100% satisfied with the experience you have had with the Wilksch engine. I imagine that is because as you said your self, you enjoy being a pioneer, and working through the technical challenges that come along.

The problem is (and this one point is the primary reason some people have the perception that "Van's" hates alternative engines) that the majority of kit plane builders want to spend their money on a proven, reliable power plant that once they finish building the airplane all they will have to do is turn the key and fly it. That doesn't mean that a lot of them aren't also interested in innovation and new technology. And there in lays the problem.
People are regularly fooled in to believing that they can have both, when the reality is, it is rarely the case. In fact I am not aware of any alternative power plant for installation in RV's that have yet met that standard. In fact even some of the hybrid Lycoming style engines built by others have gone through some development challenges.

Hopefully this explains what sometimes comes across an cynicism from Van's or others here in the forums, is actually the voice of realism and a desire to hear the whole story.
People literally make purchase decisions in the realm of tens of thousands of dollars based on what other say (or don't say) about particular products.

Hopefully some of these discussions help prevent people from making a decision that even though it was right for someone else, would not be right for them.

Side note: Everyone at Van's would love to see a viable alternative to a Lycoming power plant emerge on the market.
It would be a win - win for everyone (except maybe the people that produce the engines we currently use).

What makes an engine a viable alternative? It needs to be better than the engines we currently use in at least one of three areas, without sacrificing in any of the others.

Installed cost

Performance

Reliability


The first two are somewhat easy to define, though there are companies in business right now who are not entirely truthful but eventually word gets around (unfortunately that sometimes requires a lot of people loosing a lot of money before that happens).

The last one is more difficult. And unfortunately because of the small market that exists within the kit plane industry, the early adopters end up being the ones the prove or disprove whether it meets the current standard.

BTW, exceeding one or two of the standards but missing the mark on a third (particularly if it is reliability) does not make an engine a good alternative in my opinion.
 
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Most of us will be happy to see a viable alternative to the Lycoming, but we need real data. Some of us are extremely jaded when it comes to the performance claims of the various alternative engines, and believe me, many of us can pick out when the comparison data has been cherry picked to put the Lycoming in an unfavorable light. I recognize that some still believe that even a common practice like LOP with a Lycoming is akin to witchcraft, but come on, it is not 1960 anymore. There have been some significant advances in ignition and fuel injection which makes the basic Lycoming architecture an impressively efficient means to convert fuel into thrust.

By all means, continue to experiment, but please provide relevant data... Hard data is the most effective sales pitch, after all.
 
Kurt, that wasn't at YOU. It was at the manufacturers. You got lied to. There are other choices than lyclone, just not for most people. For me, reliability/predictability is so high on the list that the rest is kind of a distraction. I just don't want to die because I tried to get ahead of the pack. If I wanted to tinker and takes laps around the patch it'd be different. When I leave the pattern I want to feel good, not scared.
 
Search RV-10TDI, several threads on the engine which is still being tested. I don't think any price has been finalized yet.
 
Correct. And when it reaches the market, it will be a CD-265. Continental considers the 230 to be a development mule.

See "Jet A For The Rest Of Us", in Kitplanes.
 
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