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New diesel unveiled

"Continental is aiming for a price premium only slighter higher than its avgas engines"

I'm sure this means an additional $20k.

I would love to have a diesel, just wish it was more affordable, then again, I suppose I wish all engines were more affordable. Glad to see the development of diesel has not died, it seems news about it has decreased over the past couple years.
 
Diesel engines belong in big boats, monster road building equipment and farm tractors. Not airplanes.

The Germans used them in WWII and nothing ever came of it. Zoch engines have been "under development" for at least 30 years. No one seems to be able to make them work in an airplane.

If one wants to burn jet fuel, maybe a jet engine is the answer. I like jets, they run forever. We had 2 of 4 JT3D's on a 707 at TWA that were never removed from the airplane since new until it was retired to the bone yard after some 36,000 hours of flight time. And then the engines went to the Air Force to upgrade a KC135 to fans.

We will never seen a diesel engine in this market because they make no $$$ sense and never have. Sorry.
 
David-aviator said:
Diesel engines belong in big boats, monster road building equipment and farm tractors. Not airplanes.

The Germans used them in WWII and nothing ever came of it. Zoch engines have been "under development" for at least 30 years. No one seems to be able to make them work in an airplane.

If one wants to burn jet fuel, maybe a jet engine is the answer. I like jets, they run forever. We had 2 of 4 JT3D's on a 707 at TWA that were never removed from the airplane since new until it was retired to the bone yard after some 36,000 hours of flight time. And then the engines went to the Air Force to upgrade a KC135 to fans.

We will never seen a diesel engine in this market because they make no $$$ sense and never have. Sorry.
Click to expand...

Diesels have been flying in Europe for years. The Germans also didn't have the technology of today. Think how far diesels have come in cars over the past 10 years. Gone are the clunky, smokey, dirty things we all grew up with that no one wanted to drive. Diesel BMW's, VW, etc carry a premium because they're so sought after. The simple physics of it allows them to run longer and more efficiently than gasoline. Plus jet fuel is cheaper in 95% of places and more readily available. In the last 5 years FADEC systems have progressed lightyears than in the 25 years prior, and once they crack the CRD nut on aircraft engines, you'll see them explode (market wise, not literally). Give them another couple of years, especially as leaded avgas goes away, you'll see them more and more.

If I can get a diesel for 3-5 grand over a comparable gasoline engine, I can recoup that cost in as little as 500 hours.
 
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I agree, the company that developes the affordable lightweight Diesel for aviation will make a lot of money. Especially if it fits into the light sport category.

Remember, Rotax makes the engines in all those new drone aircraft. I am sure the military would love to have something that uses Jet.
 
FresnoR said:
I agree, the company that developes the affordable lightweight Diesel for aviation will make a lot of money. Especially if it fits into the light sport category.

Remember, Rotax makes the engines in all those new drone aircraft. I am sure the military would love to have something that uses Jet.
Click to expand...

The fuel costs for the Predator are so miniscule they don't even keep track. They purchase MOGAS locally.

The only other UAV's used in large numbers are all jet fuel users.

I think if TCM doesn this right they could produce a cheap experiemental engine (i.e. non-certified) in the 320-360 category that could completely change homebuilts. I predict that will be their first market and money maker. It's going to take some time to smooth things out first. AVGAS is going away, the shift has to be made. Looks like they're poising themselves to be ready when it happens.
 
Sig600 said:
The fuel costs for the Predator are so miniscule they don't even keep track. They purchase MOGAS locally.
Click to expand...

Oh I know, heck, the $25k for the rotax is nothing on a $4 million drone anyway. I was thinking more along the lines of availability and mobility, with the majority of military vehicles being diesel.

It's a moot point, I was just brainstorming.
 
Maybe

The demand for a RELIABLE aero diesel is unquestionably there especially in Europe where it makes huge economic sense however the Thielert engine was a complete disaster as it wasn't reliable at all. Hopefully the aviation press will be more objective this time around- the Thielert was billed as the second coming even 2 years after widespread reliability problems became known.

Second, the published SFC for the SMA is barely better than a Conti 550 LOP in cruise although I suspect overall mission fuel burn will be around 15-20% less with the taxi, takeoff and climb factored in. JET A availability at smaller airports is a factor in North America as well.

The big question remains price and reliability. There are not enough flight hours on the small SMA fleet to draw any conclusions at this point IMO. Personally I'm doubtful that the published 3000 hour TBO will be a reality. How many engines have made it there? Any?

The very high boost pressures (80 in. hg. Ab) run in these engines puts high gas loading on rings and pistons. These factors proved too much for the Thielert at least in the real world with many lasting less than 300 hours before removal. Many people blindly think that terrestrial diesel longevity will translate directly to lightweight aviation applications. I believe the SMA is limited to 12,500 feet because the turbo is working up against its rotational limit at that altitude so that could be a drawback for some applications.

SMA has been at it for over a decade so things should be getting worked out by now. Continental made a good move here I think- hopefully if they sell a lot more, the price will come down a bunch from the roughly $75K SMA has been asking. Kudos for Continental in taking the leap and trying to introduce something new to the market that many people want. SMA I think was also planning to offer their engines for experimentals- maybe an RV10 although 230hp is a bit on the low side. Rumors are a 300hp version is in development.

I'll be watching with interest and hope it works out well.:)

An interesting article I stumbled on: http://www.shell.com/home/content/aviation/aeroshell/technical_talk/techart19.html
 
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FresnoR said:
I agree, the company that developes the affordable lightweight Diesel for aviation will make a lot of money. Especially if it fits into the light sport category.

Remember, Rotax makes the engines in all those new drone aircraft. I am sure the military would love to have something that uses Jet.
Click to expand...

The Predator B uses a turboprop engine. edit- predator b = MQ 9 reaper
 
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Great move for Continental

I just flew my Jet A powered RV9 to California and back this morning, burning 4.8 GPH, averaging 155 mph, with two 190 lb men and full fuel. I've got 148 hours on it so far, with zero problems.

I agree that avgas IS going away, and as I have said before in this forum, in my opinion, the first major engine manufacturer to come up with a viable diesel aircraft engine is going to do well with it.

From what I understand, the US military is using several of the Thielert engines in their UAV's, with good success (there's a copy of a letter from the military on dieselair.com stating they've never had a failure). I agree, Thielert's had a lot of problems, but they're working hard to put them in the past. Their engine/PSRU is a VERY complicated package, compared to my Wilksch with direct drive, no electronics, etc., but the point is they are moving forward, along with many others. Obviously, not all of them will make it, but IMO, we will see some quality diesel aircraft engines become popular in the future.

Everyone's hoping that someone will invent and market a viable alternative to 100LL, but the fact is, the market is relatively small for it. Granted, it is unreasonable to think that the entire avgas-powred fleet should convert to JetA piston engines, but we've got to start somewhere. So I salute those who are doing it.

Kurt
 
Another aerodiesel

Here's another engine that has been in development for some time:
http://www.avionews.com/index.php?corpo=see_news_home.php&news_id=1090710&pagina_chiamante=index.php
Or google "CMD GF56".
It's a flat six, liquid cooled, direct drive, two stroke. 5600cc. 310 hp for take-off. 484 lb.

The weight is similar to the SMA / Continental, but with 80 more HP.

There's a YouTube video of it during a test run.

I like the two-stroke diesel because it gives smooth operation with less weight, and less boost required to make the rated power.

As Ross points out, the fuel economy is not leaps and bounds better than a properly leaned gasoline engine, but it is definitely better. But the real savings comes when I run non-taxed diesel. I'm paying around $2.50 / gal for that. In the winter I run Jet A just to be safe. And it is very nice not to worry about mixture, LOP for cruise, carb heat, etc. I've forgotten all about that stuff.

Probably the best thing about the diesel / Jet A engine for me is the additional margin of safety it provides. We often hear about those who survived (or may have survived) a crash, only to perish in the fire. There is much less risk of this with the diesel.

Kurt
 
Kgood... what are you powering your -9 with?

In response to the military use of the Thielart engines there is one big flaw to the argument. The military has unlimited resources to maintain them, and trained people to do it. If a FADEC box so much as hiccups, they'll replace it and not flinch. $15K for a new one is basically free. Who knows if they're tearing the motor down every 100 hours, replacing parts at intervals below OEM spec, etc. I seriously doubt they are running them the same way a civil operator would in his homebuilt. i.e. regular maint to OEM spec, or less.
 
Sig600 said:
Kgood... what are you powering your -9 with?

In response to the military use of the Thielart engines there is one big flaw to the argument. The military has unlimited resources to maintain them, and trained people to do it. If a FADEC box so much as hiccups, they'll replace it and not flinch. $15K for a new one is basically free. Who knows if they're tearing the motor down every 100 hours, replacing parts at intervals below OEM spec, etc. I seriously doubt they are running them the same way a civil operator would in his homebuilt. i.e. regular maint to OEM spec, or less.
Click to expand...

Um, yep. Pretty sure no Thielert is getting to the 2400 hour TBR advertised. When the oil consumption goes through the roof, the military just plugs a new one in. It is not like too many suffered catastrophic failures, usually slow, predictable death. The clutches are a big PITA but those just get inspected or replaced every 100 hours or so. Burning JET A or diesel is such a huge advantage for the military, I'm sure they'd like to get rid of all the SI engines for that reason alone, despite maintenance costs. The recent letter in Flying Magazine from someone in the Diamond/ Thielert debacle was not too kind.

We will see how the Austro performs in the real world in a year or two. I think the simple direct drive, low boost diesel is a better way. The 2 strokes get the weight quite competitive.

Yes, the ability to burn mogas or road diesel for those willing to haul it is significant. I save $2 gallon here using mogas now over 100LL. My fuel costs are around $27 hr.- pretty insignificant for the fun I get out of it. I spend more on insurance every year for it...
 
rv6ejguy said:
Um, yep. Pretty sure no Thielert is getting to the 2400 hour TBR advertised. When the oil consumption goes through the roof, the military just plugs a new one in. It is not like too many suffered catastrophic failures, usually slow, predictable death. The clutches are a big PITA but those just get inspected or replaced every 100 hours or so. Burning JET A or diesel is such a huge advantage for the military, I'm sure they'd like to get rid of all the SI engines for that reason alone, despite maintenance costs. The recent letter in Flying Magazine from someone in the Diamond/ Thielert debacle was not too kind.

We will see how the Austro performs in the real world in a year or two. I think the simple direct drive, low boost diesel is a better way. The 2 strokes get the weight quite competitive.

Yes, the ability to burn mogas or road diesel for those willing to haul it is significant. I save $2 gallon here using mogas now over 100LL. My fuel costs are around $27 hr.- pretty insignificant for the fun I get out of it. I spend more on insurance every year for it...
Click to expand...

Your insurnace goes up for MOGAS useage?
 
No, I meant I spend more on the annual insurance bill than I do on fuel in a year of flying. Flying has been very cheap since I built the 6A with the Subaru- compared to the days of renting wet at $90-100/ hr. say 6-7 years ago. That assumes you don't count the cost of the airplane of course but that cost has been mostly written off through my company now as it is used for product testing and advertising. I am very fortunate and think about that every time I open the hangar door to go for a zip.

Using mostly mogas saves about $11-12/ hr. over straight 100LL.
 
Sig600 said:
Kgood... what are you powering your -9 with?

In response to the military use of the Thielart engines there is one big flaw to the argument. The military has unlimited resources to maintain them, and trained people to do it. If a FADEC box so much as hiccups, they'll replace it and not flinch. $15K for a new one is basically free. Who knows if they're tearing the motor down every 100 hours, replacing parts at intervals below OEM spec, etc. I seriously doubt they are running them the same way a civil operator would in his homebuilt. i.e. regular maint to OEM spec, or less.
Click to expand...

You are 100% right about that! I know that folks with the Diamond TwinStars could not be too happy with the required maintenance. I once had a look at one apart at a college in Utah, and I was amazed at the complexity of the installation of the Thielert. I'm sure the Austro is similar. For me, it was a big turn-off. But the up-side is that the technology is evolving.

Mine is a Wilksch WAM 120. The April 2010 Kitplanes magazine had an article about my plane. http://www.vansairforce.net/delete_eventually/0410-0817.pdf. Marc Cook of Kitplanes send a PDF of the article to VAF when it came out. It's VERY old news, but you can still find it here:)

I've been pleasantly surprised at how well the engine has worked out so far. It's just like every other diesel I own - just get in, drive it, and enjoy the savings. The part I enjoyed most was developing the installation.

Now that I've got a few hours on it, I have found that there are a few things I can do to reduce cooling drag and make it even more efficient, but I'm having too much fun flying it! I do, however, intend to get started soon.

Kurt
 
Very cool article and plane. I love it.

Ironically I was just over Bishop today coming up a low level route at 500'/480kts. I have a feeling you use less Jet A :D
 
kgood said:
You are 100% right about that! I know that folks with the Diamond TwinStars could not be too happy with the required maintenance. I once had a look at one apart at a college in Utah, and I was amazed at the complexity of the installation of the Thielert. I'm sure the Austro is similar. For me, it was a big turn-off. But the up-side is that the technology is evolving.

Mine is a Wilksch WAM 120. The April 2010 Kitplanes magazine had an article about my plane. http://www.vansairforce.net/delete_eventually/0410-0817.pdf. Marc Cook of Kitplanes send a PDF of the article to VAF when it came out. It's VERY old news, but you can still find it here:)

I've been pleasantly surprised at how well the engine has worked out so far. It's just like every other diesel I own - just get in, drive it, and enjoy the savings. The part I enjoyed most was developing the installation.

Now that I've got a few hours on it, I have found that there are a few things I can do to reduce cooling drag and make it even more efficient, but I'm having too much fun flying it! I do, however, intend to get started soon.
Kurt
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That was my problem and I was having way too much fun with it to modify the cowl.
 
500' 480kt!?

Sig600 said:
Very cool article and plane. I love it.

Ironically I was just over Bishop today coming up a low level route at 500'/480kts. I have a feeling you use less Jet A :D
Click to expand...

I gotta watch out for people like you when I'm flying over there. Yesterday's flight was from Boulder City to Trona, CA, crossing a couple of MOA's. If someone like you came along, I'd never know what hit me!
Kurt
 
Yes, you need to keep your eyes out around there. The 2508 and surrounding MOA's are used by China Lake, Lemoore, Nellis, El Centro, Miramar, and a few others I'm probably forgetting. It's the wild west out there and there is a LOT of mil activity around there. By a lot I mean a LOT. I've personally been up that valley below 300' at the speed of heat many times. While we try and keep our eyes out and radar up, the terrain causes a lot of false radar hits and it's extremely hard to rely on it to pick out low/slow civil traffic. Throw in anything dynamic involving multiple a/c and forget about keeping eyes out for the little guys.
 
kgood said:
You are 100% right about that! I know that folks with the Diamond TwinStars could not be too happy with the required maintenance. I once had a look at one apart at a college in Utah, and I was amazed at the complexity of the installation of the Thielert. I'm sure the Austro is similar. For me, it was a big turn-off. But the up-side is that the technology is evolving.

Mine is a Wilksch WAM 120. The April 2010 Kitplanes magazine had an article about my plane. http://www.vansairforce.net/delete_eventually/0410-0817.pdf. Marc Cook of Kitplanes send a PDF of the article to VAF when it came out. It's VERY old news, but you can still find it here:)


Kurt
Click to expand...

Thanks Kurt, I spent a half hour last night trying to find this on VAF to re-read. Fascinating. Glad the WAM is working well for you and thanks for having Van's do the test.
 
Van's WAM RV9 test

rv6ejguy said:
Thanks Kurt, I spent a half hour last night trying to find this on VAF to re-read. Fascinating. Glad the WAM is working well for you and thanks for having Van's do the test.
Click to expand...

Thanks Ross,
It was a pleasure to work with Ken Krueger during the testing. He was very careful to explain everything he wanted to do, and then we carried it out. He's a real gentleman. Marc Cook was also really pleasant to fly with.

When Ken and I were landing after our last flight, I made the worst landing of my life!:). I made Ken promise not to tell anyone.

I have put 75 hours on the plane since that day of testing, and have done some more testing of my own, based on the what we did. I did this because I was a bit disappointed with the top speed at 10,000' and 12,000', compared with the o-320. Turns out, I can get more speed by going full throttle and increasing the pitch. Should have tried that! Oh well, live and learn.

It's a shame that Van's didn't have an O-235 RV9 to test against. It would have been more of an apples-to-apples match-up if they did. But with the O-320 loafing along at my slower speeds, the WAM still was more economical. And Ken was right, my cowl flaps do slow me down in the climb. The cowling mods I plan to make will eliminate the upper cowl NACA inlet and associated flap. From my earlier testing, the lower flap does not affect the speed as much as the upper flap does.

Kurt
 
Interesting. Yes, I would have liked to see how performance and fuel burn was compared to the O-235 but not too far behind a 320 speed wise on less fuel and sounds like you could of had a few more knots with the prop setting.
 
The "diesel revolution" in Europe was caused by one single thing, the development of electronically controlled common rail direct diesel injection, causing small diesel engine to have 40-50% more power and use 20% less fuel than the previous generation of turbo charged IDI engines. The previous generation had approximately the same power as gasoline powered (non turbo) engined, but with much less fuel consumption.

The SMA is a previous generation engine, while the Thielert and the Austro are of modern design.

The SMA runs at one RPM all the time, so it is probably very efficient even though it is an old design?, and it will work with a flat battery.
 
SvingenB said:
The "diesel revolution" in Europe was caused by one single thing, the development of electronically controlled common rail direct diesel injection, causing small diesel engine to have 40-50% more power and use 20% less fuel than the previous generation of turbo charged IDI engines. The previous generation had approximately the same power as gasoline powered (non turbo) engined, but with much less fuel consumption.

The SMA is a previous generation engine, while the Thielert and the Austro are of modern design.

The SMA runs at one RPM all the time, so it is probably very efficient even though it is an old design?, and it will work with a flat battery.
Click to expand...

You're right. Electronic common rail DI is a wonderful thing for the diesel world. At the end of the day, I think it will end up in all of the diesel aircraft engines.

I think the reason that SMA and Wilksch have stayed (and I imagine will continue to stay for awhile) with the "old style" injection system is that it is A. Simple, B. Low pressure, C. Requires no battery power to run optimally.

The Thielert and Austro are "modern designs", but they are still automotive engines, needing complicated (not to mention heavy, bulky, and problematic) clutches and gearboxes.

The CMD GF56 has common rail DI, direct drive, two stroke, and is a flat engine. To me, they're getting closer to the "perfect aircraft engine". About all it's missing is air cooling. I'm not sure that's a bad thing; I'm liking the liquid cooling in my WAM.

Kurt
 
Mike S said:
Dont tell that to anyone with an first generation GM/Isuzu DuraMax.
Click to expand...

Yeah, I have one of those ('01). I had to put the new injectors in it at around 130,000 miles and they weren't cheap. It now has over 350,000 miles on it. The new ones are definitely better.

This is why I like the "old style" mechanical injection systems with a rod or cable between my foot (or my hand, in the plane) and the injector pump.

The aircraft engines with mechanical pumps and low pressure injectors will not be quite as efficient or clean burning as the electronic common rail ones, but IMO they'll be more reliable and predictable.

I"m very happy with the WAM fuel consumption, and I'm told that the factory and others are working on ways to gain more efficiency with the current basic design. I'll be ok with that until LOTS of testing has been done with the electronic systems.
Kurt
 
Deltahawk

The Deltahawk looks like a good engine to me. It has many of the right characteristics: direct drive, mechanical fuel system, very low parts count, liquid cooling, hyd. prop governor. It is a "scavenged loop" engine, meaning it has no valves or valve train. It is ported for both intake and exhaust. The WAM and CMD two-strokes are "uniflow" designs, with ports for intake and valves for exhaust.

Detroit Diesel made "scavenged loop" engines in the 50's with decent success; many are still running today in boats and trucks. They switched to the "uniflow" design after that.

The big problem with Deltahawk, however, is that (and this has been discussed many times in this forum) they can't seem to get the darned thing to market. If they could just get a few of them in the air with happy customers and build some time.....

Yes, they are pricey, but when you consider that the cost includes the prop and some accessories, and that you get a Jet A engine with turbo and all, I think that would not necessarily be a deal-breaker for a lot of people. And, of course, as the engines become popular the price should go down.

It's a bit heavier than a Lycoming too. But I've seen quite a few gasoline auto engine conversions in RV's that are quite a bit heavier, so I suppose it's a challenge that could be overcome.

I sure hope they're successful. They've put a lot of time and effort into it.

Kurt
 
It's my understanding that common rail electronic injection gives minimal gain in fuel economy at constant high power settings over the old mechanical injection (assuming it is properly set up). Common rail was mainly developed for changing throttle conditions, noise, vibration and emissions for ground based applications.

Maybe this is a case where simple, mechanical systems are not a bad idea on aero diesels.

I must say I was impressed driving behind a 2010 Dodge BlueTec last week. This is the first diesel I could not smell at all and zero smoke through the whole load range. Meets latest emissions without urea injection too. I guess the clean diesel has truly arrived.
 
rv6ejguy said:
I must say I was impressed driving behind a 2010 Dodge BlueTec last week. This is the first diesel I could not smell at all and zero smoke through the whole load range. Meets latest emissions without urea injection too. I guess the clean diesel has truly arrived.
Click to expand...

My previous 2004 Chevy Silverado diesel, as well as my current 2008 model have had zero smoke, no smell, and are quiet in the cab. They've been impressive and powerful engines. Quite a difference from the old days!

L.Adamson --- RV6A
 
I gotta say that picture of Kgoods plane on take off, belching out smoke like an F-350 under full throttle, makes me smile. Awesome. Just need a big Peterbuilt smoke stack.

Kgood, question for you, is there a fab'd installation coming out for the WAM application? Particularly for the RV-7? I love the way yours looks, and it sounds like once the cooling issues are resovled sans cowl flaps it'll pick up some more speed. However I'm not talented enough (or motivated) to fab up a one-off design to make it work. I just want to bolt on and go. Any insight?

Overall, it looks like it's safe to assume the marginally more expensive engine (over a 320/360) will make up for itself quickly in fuel savings, any thoughts on that as well?

Last thing, any of these WAM setups running around here or in Europe with 1500 hours or more on them? I'm curious to see where they're TBOing at, and the cost associated.

BTW, nice job completely thread jacking this thread! 7700, ident.
 
L.Adamson said:
My previous 2004 Chevy Silverado diesel, as well as my current 2008 model have had zero smoke, no smell, and are quiet in the cab. They've been impressive and powerful engines. Quite a difference from the old days!

L.Adamson --- RV6A
Click to expand...

Isuzu makes a nice diesel, don't they?
;)
 
L.Adamson said:
My previous 2004 Chevy Silverado diesel, as well as my current 2008 model have had zero smoke, no smell, and are quiet in the cab. They've been impressive and powerful engines. Quite a difference from the old days!

L.Adamson --- RV6A
Click to expand...

This was the first diesel I've driven behind where I could not see or smell ANY sign it was a diesel. Previous Chevy diesels, yep , I can still smell them. My nose is tuned for 1 ppb diesel. The stuff gives me a headache in big doses.

People were saying many years ago now that the new VW diesels were smoke and smell free- hmmm. Not even close to my nose but compared to a 1980 diesel rabbit which would obscure the entire landscape around it at WOT- yes, WAAAAY cleaner. Things have come a long way in the last 7-8 years all right.

Question Kurt, why is the WAM pump not set up better? Lots of smoke means lots of waste? Do they have a boost reference on the pump like some old Toyota diesels? How close is the higher hp WAM to release?
 
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rv6ejguy said:
People were saying many years ago now that the new VW diesels were smoke and smell free- hmmm. Not even close to my nose but compared to a 1980 diesel rabbit which would obscure the entire landscape around it at WOT- yes, WAAAAY cleaner. Things have come a long way in the last 7-8 years all right.
Click to expand...

The new common rail VW diesels with diesel particulate filters (2009-2010)would defiinitely surprise you. The inside of the exhaust is white glove clean after 10,000 miles. No soot at all, ever.
 
engineerorange said:
The new common rail VW diesels with diesel particulate filters (2009-2010)would defiinitely surprise you. The inside of the exhaust is white glove clean after 10,000 miles. No soot at all, ever.
Click to expand...

I was riding my bike behind a new TDI VW last week and yes, no smoke and I could barely smell it. I used to cringe any time I heard diesel clatter coming by me on the bike, knowing I was about to be gassed and sooted out.:mad:

With the new stuff, I hardly notice.:) Not that this is a big concern in aviation diesels (trying to get back on topic) but it is nice to see some evolving technology being applied to diesels and nice to see some successful installations on experimentals. As you know, I find anything other than a Lycoming interesting in an RV!

Kurt and other WAM users, please keep us up to date on your experiences and new developments.

BTW, I'd be interested in any info from VAF members who have long term experience with the SMA diesel in any certified aircraft too.
 
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Peterbilt smoke stack? Good idea!

Sig600 said:
I gotta say that picture of Kgoods plane on take off, belching out smoke like an F-350 under full throttle, makes me smile. Awesome. Just need a big Peterbuilt smoke stack.

Kgood, question for you, is there a fab'd installation coming out for the WAM application? Particularly for the RV-7? I love the way yours looks, and it sounds like once the cooling issues are resovled sans cowl flaps it'll pick up some more speed. However I'm not talented enough (or motivated) to fab up a one-off design to make it work. I just want to bolt on and go. Any insight?

Overall, it looks like it's safe to assume the marginally more expensive engine (over a 320/360) will make up for itself quickly in fuel savings, any thoughts on that as well?

Last thing, any of these WAM setups running around here or in Europe with 1500 hours or more on them? I'm curious to see where they're TBOing at, and the cost associated.

BTW, nice job completely thread jacking this thread! 7700, ident.
Click to expand...

I'll try to answer a few of your questions:
Best as I can tell, for the time being, there's no "plug and play" FWF package. But - with VERY little work, one could be had for the RV9 or '9A. There are now six of them flying in the UK, and one of the builder groups (the one with the most flying hours, around 350) has just developed a new cowling that utilizes the "stock" WAM cooling package that puts the intercooler and radiator in front of the engine. It's a good looking cowling, IMHO, along the same lines as the RV12, and from what I hear one of the guys is getting 140KT cruise straight and level. Not bad. And Wilksch has the mounts available; the instrumentation comes with the engine. So, really not much extra work to mount one than it would be for a LYC, as long as you're ok with using the stock cooling package.

The WAM 120 would be too small for the RV7, so I'm afraid you're out of luck for now. The WAM 160 4cyl would be perfect, but I'm pretty sure they won't be producing it for some time. When they do, I would love to have one. I was visiting with Mark Wilkch a while back, and he said that was a big regret, not doing the 160 first. I don't think he realized just how much work and time it would take to get the 120 to market. Heck, they're still working on getting it "just right", which brings me to the next subject:

To answer your question, Ross, the smoke is not a big issue for me, because it only smokes on take off. Once I back off the power, it cleans right up. But it's a concern in Europe, so that's one of the things they're working on. It has to do with the combustion chamber, and, as you say, the fuel pump set-up. I don't think aerodiesels will ever be as clean as the automobiles because of the extra weight (just like Avgas engines) required to clean them up, but there are ways to get them pretty clean. They'll get there.

As far as cooling drag goes, you've got to remember that OAT at my home airport gets to over 120 degrees in the summertime. I've designed my cooling system to work in that kind of heat. The UK WAM RV9 guys don't need cowl flaps. But as far as I'm concerned, the flaps are good, since I can close them in cruise and thereby gain speed when the cooling demand is low. I have a very simple system, and it works with a simple toggle switch.

As for cost, my engine did not cost much more than a LYC O-235 would. The prop was expensive, though. They've raised the price of the engine a little now, but depending on the exchange rate, it's not a deal-killer. At the end of the day, I'm not sure how many hours of flying it would take to offset the extra cost, as that's not why I did it. But eventually, it should pay off.

Now the Peterbilt smoke stack: there's a WAM owner in Brazil with a high wing Conquest 180, he posted a picture on another forum with smoke stack sticking out of the oil door in his upper cowling, as a joke. It was great! Of course, around my office there have been lots of the same kind of talk!

Sorry about hi-jacking the thread, but, as you can tell, I get excited when the subject of aero-diesels comes up.

Kurt
 
Two more answers

Ross and Sig600,
I forgot to answer a couple of questions:
1. As far as I know, there are no WAM's near the 1500 hour mark. Last I heard, the factory's Thorpe had 450-500 hours on it. As I said in another post, there's an RV9A owned by a group in the UK with around 350 hours on it. The recommended TBO for now, If I remember right, is 1000 hours, to be safe, just about like any new engine.
2. The higher hp WAM (140 hp) "big bore" version is in endurance testing now, so I'm told, but I have not heard a release date. I have, however, been told that I'll be one of the first to get one:), so I'll be sure to let ya'll know. It is the same basic engine, with some changes to the combustion design and pistons, so it will bolt right in. And I'm pretty sure my cooling system will handle the extra HP.

Kurt
 
Has anyone heard anything about this company?
http://ppdgemini.com/
I saw them at KOSH 08 and they were supposedly about ready to start selling the 100HP version for LSAs then work on the 200HP version. Sounded like a promising alternative, but they haven't updated their web site for a couple of years.
 
kgood said:
Ross and Sig600,
I forgot to answer a couple of questions:
1. As far as I know, there are no WAM's near the 1500 hour mark. Last I heard, the factory's Thorpe had 450-500 hours on it. As I said in another post, there's an RV9A owned by a group in the UK with around 350 hours on it. The recommended TBO for now, If I remember right, is 1000 hours, to be safe, just about like any new engine.
2. The higher hp WAM (140 hp) "big bore" version is in endurance testing now, so I'm told, but I have not heard a release date. I have, however, been told that I'll be one of the first to get one:), so I'll be sure to let ya'll know. It is the same basic engine, with some changes to the combustion design and pistons, so it will bolt right in. And I'm pretty sure my cooling system will handle the extra HP.

Kurt
Click to expand...
140 hp hmm, this could work on a 4 :)

Do you have any more info on the 140 HP version?
 
Last edited:
flytoboat said:
Has anyone heard anything about this company?
http://ppdgemini.com/
I saw them at KOSH 08 and they were supposedly about ready to start selling the 100HP version for LSAs then work on the 200HP version. Sounded like a promising alternative, but they haven't updated their web site for a couple of years.
Click to expand...

I believe their engine is a spin-off (or rip-off) of these two companies:

http://www.dair.co.uk/
http://www.dieseltech.cc/ (using dair's design under license, if at all)

dair's site dates back to at least 1999.

Like Zoche, lots of promise and no deliver.
 
What Kurt and the gang in the UK has done is outstanding. What is even more impressive is the low empty weight Kurt was able to achieve. IIRC, it was 940 pounds empty, a full 50 pounds lighter than my -9 w/ the O-290 up front.

Think about that for a minute, that leaves Kurt with a 810 pound useful load! (The RV-9's recommended GW is 1750 pounds.) You just can't put that much "stuff" in a two seat RV.

kgood said:
... It's a good looking cowling, IMHO, along the same lines as the RV12, and from what I hear one of the guys is getting 140KT cruise straight and level. Not bad.
...
Kurt
Click to expand...

To put this in perspective. My 135 hp O-290-D2 with a climb prop would cruise at 140 knots while burning around 6.5 GPH of 100LL. Because of the climb prop, I would be on the redline at 65% power. That was at an empty weight of 990 pounds, forty heavier than Kurt's.

Kurt, keep the updates coming. As an old boss of mine used to say, "You can spot the pioneers by looking for the people with the arrows in their butts."
 
I"m slow building a -10. No clear answer when I'll be done as I want an IFR platfrom with Glass and I simply don't have the jack to get what I want so I'll wait until I do.

The availability of 100LL has me thinking I need to consider options. MoGas isn't really viable as it simply isn't available at enough places for serious consideration as a cross-country traveling machine.

With recent moves by EPA the handwriting is on the wall. 100LL is going away sooner rather tha later.

Jet A seems obvious choice. So I'll be watching this space and development.

Haven't really followed what Lycoming is doing but I'm sure they are not keeping their head too far in the sand.

Of course I drooled at the baby turbos that Rolls Royce was showing at Oshkosh but at optimum altitudes of 17K or so to get fuel burn down and resulting TAS well beyond safe operating range for RV-10 (flame suit on as yes I'm purely speculating) not to mention the fact I wasn't brave enough to ask the price of one I'm thinking piston diesel is the powerplant from the past for the future.

Other option is a near run out O-540 I can nurse for a coulple of years but I hate cowlings and don't want to do it but once....r
 
Sig600 said:
Kgood,
Thanks for all the info. You taking your 9 to Oshkosh this year?
Click to expand...

I'm thinking about it. We're all kinds of busy this summer doing things with the kids, but I'm going to see if I can get one of my sons to go.

Bill, my actual empty weight when I first flew was 974 lb, without paint, wheel pants, gear leg fairings. I also added 5-6 lbs with my cowl flap system. So I suppose that now it weighs closer to 1000 lb. Still not bad for a diesel airplane.

Kurt
 
kgood said:
I'm thinking about it. We're all kinds of busy this summer doing things with the kids, but I'm going to see if I can get one of my sons to go.

Bill, my actual empty weight when I first flew was 974 lb, without paint, wheel pants, gear leg fairings. I also added 5-6 lbs with my cowl flap system. So I suppose that now it weighs closer to 1000 lb. Still not bad for a diesel airplane.

Kurt
Click to expand...

Buddy of mine and I are trying to get a section of jets on the road to head there the last weekend. If you're going to be there shoot me a message, I want to see your plane.
 
Back to the Continental licensed SMA 350. I am disappointed that Continental did not choose to pursue their own diesel designed under the NASA AGATE General Aviation Propulsion (GAP) program in 1996. That's 14 years ago! They designed a 4 cylinder two stroke direct drive diesel with a low parts count. So if they had been really interested in this technology they could have developed this let's say over 10 years and have been flying them for the last four or so. Unfortunately, there have been many developments by Continental that never came to market or became mainstream. A couple that come to mind are the Tiara geared engines and the Voyager water cooled series that powered the round the world Voyager. You couldn't ask for better publicity! FADEC is the technology du jour, but what is the market penetration? Lycoming also designed a diesel during this time period but it never came to market. So while I am interested in the Continental engine, I do not see one in my future for many years.

http://www.nasa.gov/centers/glenn/about/fs01grc.html

In the 1980s the Wankel engine was under development by Curtiss Wright as an industrial and aircraft engine. It has a lot going for it: rotary motion instead of reciprocating, therefore smoother, compact frontal area, few moving parts therefore simpler and lighter, multi fuel capability which means it can be made as spark ignition or diesel, and lower octane/cetane tolerant. Much of this development was government funded. The programs led to demonstrator engines that proved the viability as an aero engine. A turbocharged watercooled diesel Wankel engine would have been an ideal solution, but for a variety of reasons, it never came to market.

100LL Avgas is currently under threat because of the recent EPA notice of rulemaking. Eventually tetraethyl lead will be banned in all fuels and then what? I think the most likely outcome is the ASTM 94UL. It is a close relation to premium Mogas. The feedstock is already there in the refinery process in large quantities for automobiles. Some different additives and special handling will result in a price above Mogas. This will satisfy almost all smaller non turbocharged engines. The large turbocharged ones that were certified for 100LL may require some modifications. Or perhaps this is Continental's strategy: to have a 300+hp diesel available to replace these engines which are primarily in commercial service? In other words, replace these engines instead of modify them. There will always be some form of Avgas for the legacy fleet of piston engines, at least in North America. Which means there is little reason to offer a small diesel aero engine in this market. Now in the rest of the world, the distribution and storage costs mean Avgas just may not be available at the airport, but Jet-A will be to serve the turbine powered aircraft. This is a big driver, and is why the first two diesels in the market, SMA and Thielert, were European, not American.

The popularity of diesel cars in Europe, and their development into a refined, powerful (and high torque) engine was driven by the fuel taxation policies of various countries the gave a break to diesel fuel over gasoline. This led to more people buying diesel cars and demanding the same refinement and performance as gasoline cars. Over the last three or four decades the car manufacturers responded and now some of their diesel cars outperform the gasoline equivalents.

I investigated the Wilksh diesel engine for my RV-9A a few years ago. At the time the WAM 160 was about to be introduced and this was the one I was most interested in. Wilksh designed a modular engine with a three cylinder, the WAM 120 (120hp) and a four cylinder WAM 160 (160hp). These are excellent designs, but since the WAM 160 has still not been offered, I have decided to use a Lycoming IO-320. I admire Mark Wilksh's company and the WAM 120, but I think it just underscores the difficulty in bringing any new aero engine, no matter what technology it uses, to market.
 
Great post and I agree with most of your analysis and points. I think there is a good future for reliable, lightweight, reasonably priced aero diesels. WAM has come closest to the hitting the weight, performance and price points. I am really impressed with what WAM has done with a small staff and resources.

One point, my pet peeve if you will, diesels might get better fuel economy than SI engines but they don't outperform them from a hp or torque standpoint per unit displacement or unit manifold pressure nor will they ever. That being said, they are well suited to powering all types of vehicles.

The current SMA is not powerful enough to replace the 350-425 hp large displacement 6 cylinder SI aero engines used in big twins but that is an important niche to fill all right. The time may be finally right to see more new diesel designs make it to the market.
 
Rotary Diesel?

Here's a lift from the past:
Rotary Power International, Inc. ("RPI")(OTCBB:RPIN) is pleased to announce it will be displaying the world's only diesel fueled marine rotary engines at the Fort Lauderdale International Boat Show between October 31, and November 4, 2002.
These were Mazda based turbocharged diesel rotary engines, 200 HP.
They would have been awesome aircraft power (maybe)
Safeboats International offered them in rigid inflatable police boats, but didn't sell well, Honda outboards being used the most.
I like the low parts count of Rotaries, and the loop scavenged 3 & 4 cylinder engines. (inverted inline or boxer type, i wouldn't care) although fuel consumption tends to be higher in ported engines, the light weight and simplicity seem good for aircraft.
 
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