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A Little Eggenfellner History

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David-aviator

Well Known Member
Truth is, Dan Horton's thread is locked down because there are mind sets here that have judged the alternative engine effort a failure and the issue is closed. Another way to say it - don't bother with me with facts, my mind is made up. No amount of "hard core technical exchange" will change that situation and yet, there is a continuing request for more information as what has been discussed does not satisfy an appetite that can not be satisfied. Sort of like feeding herring one at a time to a great white shark .

OK, what are some facts in the world of experimental engines and experimental airplanes. Zoch and Delta Hawk have been leading us around the track like dogs at a dog track going on at least 25 years. What is there to show for it - zip, nada - no one is flying behind one beyond their eternal test programs.

Eggenfellner on the other hand has bolted one engine after another on an airplane to see if it will work. His first effort was with a VEZ. It failed. Many frustrating failures along the way and a few successes - the Italian 4 seater, the GlaStar and the RV's. An effort with the Defiant, it failed but is on going - brand new engine burned up when a cooling system failed.

The clamor for more and more technical data is boring. Zoch and Delta Hawk probably have a couple semi trucks full of technical numbers but neither engine is a success in terms of EAA members flying behind one. There are many pilots flying behind a Subaru and satisfied. I am not about to suggest everything here is perfect, but these engines are working reasonable well considering the world we live in.

For those who do not like Subaru, move on to something different. But please do stop whining about the product and others who are trying to make it work resulting in threads being locked down.

We don't all pull our pants on the same way. :)
 
<<Truth is, Dan Horton's thread is locked down because there are mind sets here that have judged the alternative engine effort a failure and the issue is closed.>>

Well Dave, best I know the thread is still open. I've merely quit posting there because it has been dumbed down so badly. And it's not my thread.

Speaking for myself, I have a sincere interest in engines of all kinds. As we speak my shop contains three new engines; a Barrett IO-390, a prototype fixed pitch M14 radial, and a 2.5 Subaru. My last alt-engine aircraft (built from scratch, both airframe and engine conversion) was Suzuki-powered, and the subject of feature articles in both Sport Aviation and Experimenter. For those of you looking for a bias against alt-engines, you're looking in the wrong place. For sure, I'm not anti-anything except mechanical ignorance, and Lord knows, I've tried to remedy that problem.

Jan's packages look nice. I'd love to declare them the best thing since sliced bread. I can't because too many unknowns remain.

Airplanes fly by entirely technical means. Only angels fly on faith.
 
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Thanks Dan

... I'm not anti-anything except mechanical ignorance, and Lord knows, I've tried to remedy that problem.

Airplanes fly by entirely technical means. Only angels fly on faith.

That's the only impression I've ever taken away from your posts, Dan. There must be more folks than just me that appreciate your focus on aviation science, sans emotion. When you started that "technical only" thread I grinned and said to myself, "why isn't that the norm, rather than the exception?". :rolleyes:

Thanks,
T.J.
 
Excuse me?

It is a dangerous precedent to lock down a site because "some minds have judged the alternative engine effort a failure and the issue is closed". In other words, the thread is being blocked because a moderator is unhappy with the way the thread is unfolding, rather than any particular content that is "offside".
I have followed the thread with interest. My mind is not closed, in fact I applaud alternative engine efforts and admire those that try an alternative solution. I used to build (in a very low budget and amateur way), auto race engines and am fascinated with engine technology.
This site is about information exchange. It is of great interest to me what Eggenfellner is offering, what issues and problems he encounters, what he is preapred to share or not. It is useful to me to know what opinions/questions/considerations other builders have.
So why is the thead shut down? No one who does not wish to participate needs to. If there is no interest, it will die a natural death.
Bill Brooks
Ottawa, Canada
RV-6A
 
OK, what are some facts in the world of experimental engines and experimental airplanes. Zoch and Delta Hawk have been leading us around the track like dogs at a dog track going on at least 25 years. What is there to show for it - zip, nada - no one is flying behind one beyond their eternal test programs.

Eggenfellner on the other hand has bolted one engine after another on an airplane to see if it will work. His first effort was with a VEZ. It failed. Many frustrating failures along the way and a few successes - the Italian 4 seater, the GlaStar and the RV's. An effort with the Defiant, it failed but is on going - brand new engine burned up when a cooling system failed.

Apples and oranges. Zocke, Deltahawk, Innodyn and so on clarely (to me at least) is in it for the business opportunity. They have the technology, one or two working prototypes, and hope to be purchased for an insane amount of money when this "new and expanding" market of non-gasoline engines starts to evolve. Regardless of the facts that both Zocke and Deltahawk have some major basic design flaws, Thielert has now punctured all business opportunities. The WAM engine could really be something, but what happened? does anyone really know?

The Egg propeller reduction gear looks to me to be a homemade untested experimental prototype that is made "by heart" more than the brain. The new version may very well work OK, only time will tell, but that is also the problem: Only time will tell, and for us that are more into engineering than the average persons, this is a bit strange to put it mildly. 90% of what engineers do is to make sure that time will not only tell us something, but tell us exactly what we want to hear (with a high degree of certainty).
 
Apples and oranges. Zocke, Deltahawk, Innodyn and so on clarely (to me at least) is in it for the business opportunity. They have the technology, one or two working prototypes, and hope to be purchased for an insane amount of money when this "new and expanding" market of non-gasoline engines starts to evolve. Regardless of the facts that both Zocke and Deltahawk have some major basic design flaws, Thielert has now punctured all business opportunities. The WAM engine could really be something, but what happened? does anyone really know?

The Egg propeller reduction gear looks to me to be a homemade untested experimental prototype that is made "by heart" more than the brain. The new version may very well work OK, only time will tell, but that is also the problem: Only time will tell, and for us that are more into engineering than the average persons, this is a bit strange to put it mildly. 90% of what engineers do is to make sure that time will not only tell us something, but tell us exactly what we want to hear (with a high degree of certainty).

It seems clear that Zoche will never actually offer his engine for aircraft after all this time and if he does, it will be silly expensive. Deltahawk has much to prove as far as longevity and real world numbers go. WAM appears to be locked in a cottage industry loop. Thielert is a good example of a project with top notch, F1 level engineering behind it with considerable validation but not being up to snuff in the real world and really too expensive for experimental aviation. Their reputation is not off to a good start and they are now having to re-design from real world experience to fix some serious problems that the engineers did not get right the first time.

Engineering can help weed out many potential problems in a design but it is NOT a guarantee that this will be so. It will generally save time but maybe not money in the long run.

Read what David wrote. Jan's FF packages are flying quite successfully in relatively large numbers at prices many people can afford. I think many here have NO concept of what it takes to make a project like this a commercial success. Could someone take $2M and design a better FF package than Jan's? Undoubtedly but the unit costs would have to exceed $50K to ever recover the development costs at the quantities produced for this market.

Costs and QC are big factors in using off the shelf gears and shafts as opposed to having these parts custom made in low quantities. RWS does a similar thing successfully. You do an all custom PSRU with complete engineering and testing and you end up with A $12-13K piece like EPI offers. A nice piece but out of the budget for many.

I'll say this again, I'll take flight time on a system over a ton of theory any day but I'd like to see full TV tests done on the finished product as well so one can worry less about spinning things up front.

Jan's doing it. The others are just talking about it. There is a world of difference there.

I'd invite those who criticize Jan's methods to give the market a try for yourself. Better have plenty of financing in place before you start.
 
I'm not one to criticize anyone and I do admire one that ventures into new evolving equipment, but I wonder why people find it necessary to reinvent the engine wheel. Lycoming and Lyclones are certainly not perfect but they do work quit well and are well proving over the long hall. Sure I know there have been recalls, but isn't that what refines the aircraft engines that we use? I know that cost is a factor for new engine but there plenty of quality used engines out there.
When building my -8, I made miner changes to the construction but followed most of what Van engineered, I read many of his thoughts on different engines and decided to use what he designed to work best with that airframe, a Lycoming. The kit is designed to receive a Lycoming,, not because it's better but it works. There is little change to the kit and there are plenty of after market parts to help speed up the build time. For me I didn't want to be a test pilot when it came to the engine, I wanted to to use a engine that has been proving itself for many years, one that was designed for aircraft use.

But that's just my opinion!
 
I closed the technical discussion thread because it had run its course. Without the manufacturer engaging a discussion with the group in a technical way, the thread title could no longer be supported.

For that particular thread which I was specifically asked to moderate to keep it on track with the thread title, I closed it.

after 16 pages, lots of good discussion, it was an interesting thread which I enjoyed reading and moderating.

Id be happy to do another if someone asks. I thought the topic was worth the extra effort.

Best,
 
Airplanes fly by entirely technical means. Only angels fly on faith.
__________________
Dan Horton
RV-8 QB - Alabama

Nothing here is done by faith. We put our lives on the line every time we test a new engine package. But we do it because we believe in real world testing. Once the thing has logged 200 hr on the stand, get out of the chair and fly the thing. When someone ask me how many flight hours we have on the 2008 model 3.6, I know that they have no idea what this is all about. It is about, as safely as possible, use the latest in automotive engine technology, in an airplane.

Jan
 
I wanted to to use a engine that has been proving itself for many years, one that was designed for aircraft use.

But that's just my opinion!

And that makes you happy. We however, could never fly behind such an engine any more. Not with the knowledge of how nice an engine truly can sound, feel and run.

Just a different opinion, that's all

Jan
 
When someone ask me how many flight hours we have on the 2008 model 3.6, I know that they have no idea what this is all about.
Jan

Okay, paint me stupid but this seems like a perfectly valid question to me. Just my opinion, but I think responses like this help to generate some of the negative opinions you are trying to combat.
 
Difference of opinion, historically and subjectively

I wanted to to use a engine (Lycoming) that has been proving itself for many years, one that was designed for aircraft use. But that's just my opinion!
And that makes you happy. We however, could never fly behind such an engine any more. Not with the knowledge of how nice an engine truly can sound, feel and run. Just a different opinion, that's all Jan
That is right just a different opinion. Regardless the Lyc and Subaru are both "boxers" and both use the same thermodynamic "Otto cycle" principle, as it always has been, since discovered 130 years ago.

To be fair, as far as noise or engine sound, I like the lower throaty roar of the Lycoming than the higher frequency of most alternative engines; again just different opinions. :D As far as smooth, I am happy with a well balanced Lyc and prop; it's plenty smooth. I have not flown a RV with an Eggenfellner, but going on Van's comparative test with two RV-9A's, one Lyc one Eggenfellner powered, there was a difference, no better or worse. Van's Aircraft staff acting as the unbiased test pilot, noticed a higher frequency sound and a different kind of vibration, not quieter, louder or vibration free, just different. It was different than than the Lyc. Some vibrations and sound coming from the prop wash, plus exhaust pulse beating on the belly. They both have that.

My pet peeve is objective data verses subjective. It would be nice to put some accelerometers and noise meters in the cockpit. That would probably not do justice to either I suppose. It's like a traditional Harley Davidson, BMW Boxer Motorcycle or earlier Porsche 911's (air-cooled) sports car, verses water cooled super-bikes and sports-cars, the latter are more quite. Some still like the sound of the air cooled engine, hearing the mechanical noise. It's all subjective. I still say a Big-Ol-Radial is the best sounding of any engine, but the RV has a W&B problem with a Pratt & Whitney R-985 Wasp Junior on the nose. And if its not shaking, belching smoke, roaring, while leaking oil, its not running and there's no oil in it. :D

Some alternative engine enthusiast are found of the words "it's modern", when drawing a comparison of engines, which really means nothing. Both the Lycoming and Subaru work on identical principles, the 4-stroke Otto cycle. The design and introduction of the O-360 Lycoming goes back to 1955, O-540 in 1957. The Subaru is not much younger and is an outgrowth of the 1966 1000 Subaru engine design. Both engines draw from the 1936 VW "boxer". If you talk to a rotary engine guy, they might say neither the Lyc or Subaru are "modern". Dr. Wankel invented the rotary Wankel thru the 50's and 60's. The first commercial applications appeared in 1971. Besides being the Johnny-come-lately, the Wankel is a different concept than a reciprocating piston Otto cycle (4-stroke) engine, which was invented in the late 1800's. Regardless the Lyc and Subaru are both "boxers" using the same suck-squeeze-bang-blow cycle.
 
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But for how long? Any long term data!

We do not have long term data. Every year we start on a new engine model. Right now we are building the first 2008 3.6 engines. The core engine keep changing. The parts arouns it to convert it keep improving. Hitgest total time engine is 800 hours.

Jan
 
Quote:
Originally Posted by janeggenfellner
When someone ask me how many flight hours we have on the 2008 model 3.6, I know that they have no idea what this is all about.
Jan

Okay, paint me stupid but this seems like a perfectly valid question to me. Just my opinion, but I think responses like this help to generate some of the negative opinions you are trying to combat.

We are not trying to combat anything or anybody. Everyone can have their opinion on what engine to fly behind. It is however not opinion, but fact, that anyone I have given a ride to, in a Subaru powered airplane, rave about how much nicer and refined the experience was. It is also fact that someone expressing their opinion, without any experience behind a Subaru powered aircraft, are not doing a service to anyone. How could your opinion possibly be of any real value if you have no experience? We are not in the business to "win" customers. They find us all the time. We are in the business of making those that go this way have a good experience.
Jan
 
Some alternative engine enthusiast are found of the words "it's modern", when drawing a comparison of engines, which really means nothing.

But you see, it is the other way around. It means everything. The 2008 3.6 is superior to any air cooled direct drive engine. If you question this then I can not help :)

Jan

Jan
 
Just my opinion, but I think responses like this help to generate some of the negative opinions you are trying to combat.
Randy - I think you've hit it on the head here.

I think maybe I'm kind of a test case here... I'm building a 9A and getting close to the point where I'm going to have to select an engine. I've always thought "Lyc" but am open to alternatives. In fact, Gary Newstead showed me his Egg powered RV back in NH and I was very impressed. I thought it was very complex but smooth running and I really liked the cabin heat! So I'm certainly not predisposed against auto engines, Subaru's, or Egg.

All that being said, and the following is my choice: I don't want to be a test pilot for both an unproven airframe and & engine (but I respect those who do). That doesn't mean that I won't consider an Egg engine. I'm building an experimental plane, after all. It does mean that my first question is likely to be "how many flight hours?" on this engine. In fact, now that I think about it, that's why I chose to build an RV... I wanted to have a stable, well proven airframe. I think the number of RV's flying / flight hours was a major factor in my decision.

So, I've been lurking, reading all the posts & websites and trying to form an opinion. I enjoyed the technical thread, learned some (engineer here), and I respect Jan for both participating and for sharing data. I even respect him for holding it back, if he feels it is his IP.

Point of the post is that I think Randy is right - as a whole I now have a more negative opinion after I read what Jan thinks about builders like me.

That is unfortunate.
 
Yes the design of the Lycoming goes back to the mid 1950's. The Subaru is not much younger and is an outgrowth of the 1966 1000 Subaru engine design. Both engines draw from the 1936 VW "boxer". Regardless the Lyc and Subaru are both "boxers" using the same suck-squeeze-bang-blow cycle.

Other than the configuration of these engines all being horizontally opposed Otto Cycle engines, the similarity ends there. The EZ30 and EZ36 engines are in no other way similar to a 1936 VW engine or a 1966 Fuji design or a Lycoming.

While overhead camshafts and 4 valves per cylinder are not new at all, variable valve timing, variable induction tuning, computer modeled combustion chamber dynamics, coolant flow dynamics, airflow and injector dynamics, vibration and resonance dynamics relating to NVH and FEA employed in the design and validation of these engines do indeed make them more "modern" than the quoted examples. There is no way that any Lycoming engine can approach the smoothness or refinement of an EZ30 for example. It is simply impossible for many technical reasons. Look at the size of the engine mount rubbers used on the two engines- this is a clear indication of how much smoother the EZ is. I'd invite anyone to instrument the two engines and see for yourself.

As someone who has flown a number of alternative powered and traditionally powered aircraft, I can say that on the noise front, there is no difference subjectively between unmuffled auto and traditional engines- both are pretty darn loud and I actually find the auto engine's higher note more offensive. The turbos are much quieter in most cases and with combined exhaust streams, have a pleasant note as well. My personal choice.

While a lot of the newer technology does NOT translate into higher performance in aviation use, many people do like the smooth performance, EFI and low overhaul and parts costs. They will never have to suffer cracked heads, stuck valves, weeping oil or low compression problems nor the sticker shock of traditional aircraft engine parts. Many pilots have not had good experiences with traditional engines in the past and want something different and less expensive.

If you are happy flying your traditional engines, by all means continue- perhaps you are the type of person who still drives a 1980 Impala and thinks it is just great. But if you've never driven a 2008 Lexus, you don't have much to compare it to. Yes, the old Impala gets you to the airport, it just isn't very refined by todays standards.

When Jan mentions modern automotive technology, he is referring to the mindset of auto engine designers where having to take any part of the engine apart these days before 5-8,000 hours is not acceptable. The norm today is only to change oil and replace spark plugs every 2-3000 hours. There is no other maintenance involved typically on the better Japanese designs.

25 years ago 100,000 miles without overhaul or major maintenance was a realistic goal for most car engines, today, that figure is double or even triple. Hp at lower rpms, despite way tougher emission standards have increased substantially in that time as well. We have many direct injection 3.5 liter engines making over 300hp at not too lofty 6500 rpm levels today. Power to weight ratios have improved by 50% in many cases. This is real progress.

Lycomings still have TBO at 2000 hours. Many make it there and longer, some don't. Hp is the same as it ever was. Not much progress there in 25 years and the same issues still afflict them 25 years later because of the way they are designed and that fact that they have had minimal improvements in that time. They are predictable and well understood but they are in no way modern or exceptional engines.

Why should we subject ourselves to this level of mediocre refinement in our aircraft when most of us would not in our cars? That is the question asked by many and the reason why Jan is in business. Doing things the same old way does not interest all of us. It's kinda like saying that all planes should be painted white because it is the best color. Thank goodness we have choices...
 
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Transparency

Nothing here is done by faith. We put our
lives on the line every time we test a new engine package. But we do it
because we believe in real world testing. Once the thing has logged 200
hr on the stand, get out of the chair and fly the thing. When someone
ask me how many flight hours we have on the 2008 model 3.6, I know that
they have no idea what this is all about. It is about, as safely as
possible, use the latest in automotive engine technology, in an airplane.

Jan

I waffled about posting the following comment. Then Jan posted a few more (perhaps unintentionally) disingenuous comments.

Jan, I think Dan was implying that your customers are flying on faith.
You may not do anything on faith, you may have the most wonderful design
and testing in the world. But without published test protocols or design
specifications, your customers must have faith. In the certified world
there are a lot of assurances, the FAA PMA, the ability of any A&P to
send in a service trouble report, the authority of the FAA to issue an
AD to force a fix. In the case of Lycoming, the longevity and relative size of the company is an assurance.

In the experimental world, all we have is the transparency of the
manufacturer. Speaking for myself, the requirement for transparency goes
up in direct proportion to the cost and life safety aspects of the part
in question.

Additionally, most experimental parts are sold as individual components.
The transparency is a given in as much as the buyer is going to assemble
the components. Uniquely, your experimental product is a complicated
assembly, with workings that are not inherently transparent.

It is simply disingenuous to suggest that all your customers need is a demo flight, that there is no need for hard data.
 
Refinement is good...

If you are happy flying your traditional engines, by all means continue- perhaps you are the type of person who still drives a 1980 Impala and thinks it is just great. But if you've never driven a 2008 Lexus, you don't have much to compare it to. Yes, the old Impala gets you to the airport, it just isn't very refined by todays standards.

snip...

Why should we subject ourselves to this level of mediocre refinement in our aircraft when most of us would not in our cars? That is the question asked by many and the reason why Jan is in business.

I would love to have that "Lexus" refinement in my aircraft engine. How much safety do I have to trade for it? How much reliability? Can anyone tell me?
 
Why should we subject ourselves to this level of mediocre refinement in our aircraft when most of us would not in our cars?

To be honest, I don't like the idea of having to use a prop reduction to get high revving auto engines down to efficient prop rpms. I don't like the idea of cramming radiators and hoses in every possible spot, when an air-cooled airplane engine is quite sufficient and much simpler.

I like the idea of hydraulic constant speed props,
versus the slower electric types, including associated wiring & brushes.

As one can see, a "modern" auto engine really needs a lot of makeshift additions, to do what an airplane engine has been doing all along....

L.Adamson -- Chevy diesel Silverado -- no Impala:D
 
I watch these posts from time to time but haven't ever responded to them yet, but I do have a few comments to make. While it is great that Jan & others are attempting to offer alternatives to the pricey Lycomings, the fact is the Lycoming is still the ultimate piston engine design for GA aircraft use for a number of reasons:

1) Lightest weight for the power produced
2) Lack of a head gasket which avoids blown head gaskets when running at high power settings (the very nemesis of early designs & why all air cooled aircraft engines from World War 2 on were designed this way)
3) Air cooled design that minimizes the complexity of a water cooled issues as well as reducing overall weight
4) Price at the current time with the clones is still cheaper than alternative engines bought as a complete package (yes, perhaps someone converting a junkyard engine can do it for less, but it's doubtful that it is as reliable as a Lycoming in my opinion).
5) Much larger in cubic inch capacity and thus much less stressed than the alternative engines (and just think, they are still lighter than alternative engines that are half the cubic inches in size...how are the newer alternatives considered to be better when they can't even match the lighter weight of the Lycoming?).

While the Lycomings weren't designed originally with electronic ignitions and other more modern advancements, most all of that is now available for any Lycoming used in an experimental amateur built aircraft, so they match the Subaru & Rotary engines in that regard and still are more simplistic and more reliable. Also, alot of the previous problem areas have been designed out in the clones such that they are WAY more reliable now than even the older Lycoming engines (one of these major design changes is a redesigned oiling system that feeds more oil down the pushrods to the valves which has now all but eliminated the old valve sticking problems of the original Lycoming designs...even Lycoming has done the same by upping the oil pressure to 100 psig now to get more oil flow to the valves on all their latest new engines).

All in all, until there is HUGE advancement in some new engine design, the current alternative engines are no advancement at all and in fact can't out perform a Lycoming engine installation. That reason alone makes me wonder why anyone would pay so much money to install one...yeah if it were truely half the cost with only a 5% or less loss in performance, then yes it would be worth it! (but that is obviously not the case at this time). The reality is that the Lycoming is an extremely well designed engine for the specific mission it was designed for!! Any auto conversion is NEVER going to be able to out perform it. But, let's assume that someone does manage to match the performance at less cost, well that will only help us all because Lycoming and the clone manufacturers will then just drop their prices to maintain their market!
 
Modern v. Venerable

But you see, it is the other way around. It means everything. The 2008 3.6 is superior to any air cooled direct drive engine. If you question this then I can not help :) Jan Jan
Superior in what (that benefits aircraft use)? I have always said, when any alternative engine in the 180-200hp range, which fits my RV7, goes faster, on the same or less fuel, with a hydraulic prop and lower installed weight, than my Lyc, I'm writing a big check. We can agree to disagree my friend. :) Cheers, keep up the good work!
 
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I watch these posts from time to time but haven't ever responded to them yet, but I do have a few comments to make. While it is great that Jan & others are attempting to offer alternatives to the pricey Lycomings, the fact is the Lycoming is still the ultimate piston engine design for GA aircraft use for a number of reasons:

1) Lightest weight for the power produced
2) Lack of a head gasket which avoids blown head gaskets when running at high power settings (the very nemesis of early designs & why all air cooled aircraft engines from World War 2 on were designed this way)
3) Air cooled design that minimizes the complexity of a water cooled issues as well as reducing overall weight
4) Price at the current time with the clones is still cheaper than alternative engines bought as a complete package (yes, perhaps someone converting a junkyard engine can do it for less, but it's doubtful that it is as reliable as a Lycoming in my opinion).
5) Much larger in cubic inch capacity and thus much less stressed than the alternative engines (and just think, they are still lighter than alternative engines that are half the cubic inches in size...how are the newer alternatives considered to be better when they can't even match the lighter weight of the Lycoming?).

While the Lycomings weren't designed originally with electronic ignitions and other more modern advancements, most all of that is now available for any Lycoming used in an experimental amateur built aircraft, so they match the Subaru & Rotary engines in that regard and still are more simplistic and more reliable. Also, alot of the previous problem areas have been designed out in the clones such that they are WAY more reliable now than even the older Lycoming engines (one of these major design changes is a redesigned oiling system that feeds more oil down the pushrods to the valves which has now all but eliminated the old valve sticking problems of the original Lycoming designs...even Lycoming has done the same by upping the oil pressure to 100 psig now to get more oil flow to the valves on all their latest new engines).

All in all, until there is HUGE advancement in some new engine design, the current alternative engines are no advancement at all and in fact can't out perform a Lycoming engine installation. That reason alone makes me wonder why anyone would pay so much money to install one...yeah if it were truely half the cost with only a 5% or less loss in performance, then yes it would be worth it! (but that is obviously not the case at this time). The reality is that the Lycoming is an extremely well designed engine for the specific mission it was designed for!! Any auto conversion is NEVER going to be able to out perform it. But, let's assume that someone does manage to match the performance at less cost, well that will only help us all because Lycoming and the clone manufacturers will then just drop their prices to maintain their market!

Perform is such a broad term and never is so final. In fact, several auto conversions that I'm aware of are faster than the typical Lyconental powered aircraft. I've listed some of these previously. Perhaps you should review your data.

Head gasket failures are not an issue on the popular modern automotive engines like the Phase 2 EJ25s, EJ22, EZ30, EG33, LS-1 through LS7.

Air cooled engines operate at much higher thermal stress levels- hence their issues with cracking heads to this day. Mechanical stresses are similar on both types as has been shown before.

I do agree that the clones are overall better engines today than Lycoming's original design.

I've said before, that no commercially available packages currently match the weight, fuel burn and speed in the 200 hp class compared to Lycomings. This is not the reason people buy alternatives or there would be no market.

Other comments about PSRUs being "makeshift" don't make sense. Again, as previously mentioned, there have been way more gearbox equipped aero engines built and flown than direct drive aero engines. Today, you have your choice of several PSRUs which have hydraulic prop capability should you desire these. Again, there have been hundreds of thousands of electric props built and they work just fine unless you are doing aerobatics.
 
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I wonder if the engineers at Subaru designed there engine to work at full HP for much longer then a few minutes? Most car engines don't see much more 30% power at any time. Porsche tried to make a aircraft engine and they didn't succeed, I'm sure they have the money for R&D. Unforturely, the amount money that it would take to develop a new aircraft engine for the small amount of engines needed don't make it feasible. By the way, I would love a Lexus engine, if it were designed for aircraft!

Just my opinion, nothing more!
 
I wonder if the engineers at Subaru designed there engine to work at full HP for much longer then a few minutes?
Back in 1989, Subaru set a long duration, high speed endurance record with the original Subaru Legacy. Is an average speed of 138 mph (including stops to refuel, change tires, change drivers etc) for 18.5 days good enough for you? Certainly the engine has changed a lot since 1989, but this gives some idea of the robustness of the engine that Subaru designs.

I have little concern about the core Subaru engine. The big questions are on the PSRU, and other systems that must support the engine to allow it to keep running.
 
Well now I see that the claim is again that every engine package is run for 200 hours on a test stand before flight.

But when I asked about the RV-10 package (the old one not the 3.6) the answer was that very little teststand time had been done, but much test flying was done in Dan's (RIP) plane. Unfortunately that comment implied that the in flight testing was a cumulation of trouble free hours. Even that claim was false as everyone familiar with that tragic chain of events knows. How many hours before and after the first turbocharger melted and siezed? Any disclosure on that? What has been done to fix that problem, and how has the fix been tested?

I recieved no answer to the question of how much testing had been performed, on the stand, with each permutation of the package, including the prop. Most of the test stand testing was apparently done with a four blade prop, though I think the flying was done with two blades removed...that is certainly how the airplane arrived at OshKosh.

Maybe I am paranoid from cross examining uncooperative witnesses all day long, but I too found that most of the answers were vague or avoided (artfully) the actual question which was asked.

Smoothness? Great feature. No doubt about it a smooth engine and hot water heat are nice.

Reliable hours? No data. There was a claim that there have only been 2 gearbox failures, but the fleet is grounded, and when other examples of failures where bearings shelled out, or gears stripped, were raised we all learned that such "events" are not calculated in the failure matrix.

Speed? Ross is right that the fastest conversion examples are faster at the top end than average examples of traditional powered planes...but at what fuel burn and weight? If speed is the measure, fuel burn be damned, then we need to factor in the super 8's and others.

Ross is correct that the fuel/speed numbers are a nod to the lycoming. Ross is correct that weight is an often substantial nod to the traditional.

System simplicity also goes that way. It is not just that props are electric it is that the pilot workload to manage the controllers is high, and apparently not intuitive. A beautiful RV was just lost because the experienced pilot builder chose the wrong buttonology for the prop controller, and had insufficient power to go around. We know that Dan struggled to work out the bugs and get systems control over his "ready for prime time" prop controller. Many times making it difficult or impossible for him to get the plane safely on the ground, or to execute a low risk go around.

It is great to get rid of the red knob, but how many knobs, switches and other controls are added in the mix?

It is great to have computer controlled waste gates....but they appear to be operated by a cable hooked to a Ray Allen trim servo???? Is that safe? maybe it is, maybe the rim servos have the ability to react quickly enough to prevent an overboost or underboost scenario. All I know is that no other aircraft installation uses a cockpit mounted trim servo to manage the waste gate or blow off valve. I am not aware of any auto application which does either. Most are mechanical and pressure operated and located immediately with the valve they actuate because speed and responsiveness are critical. Again is this approach safe and reliable? maybe it is, but we have no way of knowing, we have no data to support it, and there are few if any successful flight hours to support it.

I do not object to designing by heart. Historically some of the most successful race teams did this...Collin Chapman is reputed to have removed tubes in the Lotus Seven chasis one at a time until it collapsed on it self, and then added the last tube back before affixing a rigid and structural skin. The car eventually proved reliable and was super light/fast. Many drivers died along the way. When the chasis fails mid corner, there is little one can do to recover.

In an RV, a dead stick is a far more dangerous event than in a Citabria or Cessna. The planes have short wings, and high wing loading, power off they come down like a rock. Yes a profficient pilot should be able to get it on the ground if there is a suitable place to do so, and at least some altitutde. As I get older, it seems prudent to take every step to avoid that situation all together.

It is a strange position that I find myself in because if I think "do I want a smoother, more modern engine that starts like a car, with better heat, and lower pilot workload?" the answer is unquestionably yes. But if I also ask "do I want a controlled package with KNOWN characteristics and predictable behavior" the answer is also yes. Maybe that is the problem. Maybe if a single or perhaps two or three core engines were used for many packages that were all identical, and real transparent data was available so that failures could be predicted and avoided....it would be a more comfortable proposition.

To put it in the perspective of the software world I used to inhabbit....it is fine for a small company supporting a handful of users to constantly install bleeding edge, relatively untested software because ad-hoc support issues are small. But if you run a mission critical enterprise wide application you would be a fool not to control and enforce consistency and a controlled evolutionary approach to development/change.

These are just my opinions and observations. Many will not agree. Ultimately it is a risk management decision we all must make.
 
<<Why should we subject ourselves to this level of mediocre refinement in our aircraft when most of us would not in our cars?>>

If we limit the comparison to just the engines, you're absolutely right.

Question is, when are you going to start demanding the same level of engineering for the rest of the powertrain?

Ross, you're probably the internet's #1 defender of alt-engines. Yet you're personally flying a engine package (Subaru + Marcotte) that shakes the snot out of the whole airframe when it passes through the first resonant period at 1350 RPM. The only reason it lives (so far) is because the gearbox parts are massive. What you have is an unrefined system; it doesn't work very well and weighs far more than an engineered system would require.

Now consider the Egg system. Much better by all reports; Jan's approach is fundamentally correct. However, lacking the slightest clue as to actual vibratory shaft loads, his only alternative was to create a third gearbox iteration after the first two didn't turn out to be reliable. The new box is a nice piece, but still classic TLAR design. There's no evidence that shaft loads were predicted at the design stage or measured in test. It is just "beefier", and as a result it weighs 15 more lbs.

Start demanding better and you might get it; free markets work that way. And please, on a personal note, don't shoot the messenger. I didn't spend all the time to learn "useless technical stuff" just I could could knock alt-engines. I'm one of you.....and I see how good it could be.
 
Well now I see that the claim is again that every engine package is run for 200 hours on a test stand before flight.

But when I asked about the RV-10 package .....snip

These types of posts would carry a lot more weight (at least with me) if the poster would sign their name. Or at least fill out their profile where their name can be viewed.

Best,

Doug Reeves
 
Are we still experimenters?

In the certified world there are a lot of assurances...

And yet you are building/flying an "experimental" aircraft. Hmmmm. I guess you want to build/fly an experimental, but not TOO experimental. ;)

It is simply disingenuous to suggest that all your customers need is a demo flight, that there is no need for hard data.

I didn't interpret Jan's comment in that fashion, rather in the fashion my comment above was offered; slightly tongue in cheek. Besides, Jan IS offering hard data, just not the kind of data many of the engineers on the list are clamoring for.

I very strongly doubt any VERBAL argument will create converts in the CERTIFIED vs AUTO ENGINE debate. Is there anyone here who honestly believes if Jan provided ALL the engineering data everyone is demanding it would convince any staunch Lycontinental proponents to switch camps? Perhaps Jan's suggestion for the open-minded to take a ride in an Egg-equipped aircraft isn't so disingenuous...

I suspect (as I'm sure many have already concluded on their own) that lacking an engineering education, engineering background and access to sophisticated test rigs (or the capitol to hire testing out), it's unlikely Jan will collect the kind of detailed engineering data he is being asked to share. I also suspect -- contrary to the many learned opinions here -- he doesn't believe that level of testing is necessary. C'mon guys, he's not selling a CERTIFIED product, why would he try to meet those testing standards?

What he CAN do is point to the many flying examples of his products, share his beliefs about what his customers value in them and continually demonstrate his commitment to upgrade sub-systems deemed inferior as a result of REAL WORLD use.

If that means I'll be "flying on faith," so be it. Each of us has to make a choice at the level of "experimentation" they are comfortable with. If you cannot be comfortable unless your experimental aircraft has a certified engine turning the prop, that's fine -- for you. The rest of the experimental community (at least my part of it) may not make the same choice.


Regards,

Mark Sletten
 
After two dead stick landings, two failed gearboxes, (I call a bearing failure in which the airplane is grounded a FAILURE), and having to correct way too many problems that came from the Egg factory, I am still exited to have my Subaru STI engine.

Hopefully Jan's engine packages have improved since the botched batch that I bought into. As for my engine package, I have made enough changes to it to call it mine. The only attitude that keeps me happy abut the situation is one in which I consider what I purchased to have been a "starter kit".

I could write a long list of items that had to be corrected, many of them were due to plain sloppy quality and lack of attention to detail, like the mating surface of the intake manifold that could not possibly seal for one of the latest instances discovered.

My point here is this. I am still excited and love having my engine. It has been very expensive and frustrating, but I have also enjoyed the challenge of correcting the problems and getting the engine running as best it can. This is the kind of attitude that is needed for the kind of package I purchased from Jan. Hopefully things are better now.

When it comes to doing business with alternative engine package sellers I offer this advice. Don't trust but verify. If you are not a very mechanical minded person and have a burning desire to learn and understand all about your engine and what it takes to keep it reliable in an airframe, you might be better off staying with a certified airframe and power plant.

If you are into experimenting to a lesser extent, then maybe a Lycoming or clone of one is the right engine for you. I really don't understand all the judging about one being better than the other. Sometimes it seems like the Lycoming proponents are feeling a bit threatened by the new breed? On the other hand I think some of the Sube proponents are trying too hard to justify the decision they made.

I think the day is coming when alternative engine packages will be available that are truly ready for bolt up to the airframe without any further developement needed buy the purchaser. Are we there yet... Maybe, I don't know.

I think most of the packages coming out of the Egg factory now do not need the kind of corrections that were needed on mine, I have not inspected them so I cannot say and I do not just believe what I hear. If I were buying an engine for a project at this time what would I do? To be honest I would probably either buy a good Lycoming, or make my own package with a Subaru and hopefully purchase a good quality gear reduction drive from Jan or whoever is making the best one at the time. I can say that now because I have learned so much in this process. Remember, that is supposed to be the purpose of experimental aviation, learning.

Randy C
RV7A STI engine
 
Staying a bit more on the subject, I am pretty sure I am a part of Eggenfellner's history that he would like to see go away.

Once a vendor sends a product out the door it is no longer under their control and it will speak volumes about it's quality for all the world to see.

Perhaps we can call this part of the process of natural selection for vendors. It is unfortunate for all of us that there is not more competition in this field.

Randy C
 
I wonder if the engineers at Subaru designed there engine to work at full HP for much longer then a few minutes? Most car engines don't see much more 30% power at any time. Porsche tried to make a aircraft engine and they didn't succeed, I'm sure they have the money for R&D. Unforturely, the amount money that it would take to develop a new aircraft engine for the small amount of engines needed don't make it feasible. By the way, I would love a Lexus engine, if it were designed for aircraft!

Just my opinion, nothing more!

I'd hoped I debunked this common misconception long ago. Most new auto engine designs pass a MINIMUM 200 hour WOT validation test these days which is more than what is required by the FAA for certified engines.

Dan,

I tell it like it is and don't sugar coat what I see. I have serious TV at two rpm points not within my important operational ranges. I may have more ranges that I'm not aware of because it has never been instrumented. Many Lycomings also have two ranges where you don't operate- say 150-200 rpm (wet dog zone) and the yellow arc zone and almost every engine package has a bad TV range somewhere between zero and redline rpm- even highly developed auto drivetrains. It may be acceptable to simply not operate there. Lycoming thinks it is ok.

TV is present to some degree in all packages, it is the intensity that is important and that is where instrumented analysis would be VERY useful. I'm not disputing that and I don't think it is useless. What I am saying is that after someone accumulates several thousand hours on say an engine/ PSRU package without problems, TV testing is probably a moot point as we have real world validation that the system is reliable. Gen 3/ EZ30 packages are rapidly approaching this level.

I dispute the blanket claim that Gen 1 and 2 gearboxes were unreliable. They were actually quite reliable when used with the original EJ25 engines. Some have accumulated well over 500 flight hours now. They were out of their league when applied to the much higher torque STI and EZ30 engines. A stronger box should have been made prior to release of those engines.

TV can be a very hazardous situation but we cannot assume that all PSRUs will fail from this. Absolutely in my case, I'm flying on faith as I have not accumulated several thousand flight hours on my package. I dispute your contention that the Marcotte is grossly overweight and that my package does not work very well. The M-300 weighs 47 lbs which is relatively light compared to other drives in the 300hp class. Most of any excess weight is in the adapter casting. The gearbox part is very light actually. I want beefy when it comes to spinning a big constant speed prop in turbulence. I don't want marginal bearings or castings which might wear out prematurely or crack. I purposely chose the M-300 over the lighter M-200. The Marcotte is done right IMO with a massive tubular shaft and massive Timken tapered roller bearings for the prop shaft support. The M-300 does not have a good damper/ coupler design for all engine/ prop combos. I may be changing that system but the gearbox part is very solid IMO as someone with a lot of gearbox experience.

Performance wise, my 6A easily out climbs an O-360 FP combo and is on par with an O-320 C/S at typical RV altitudes. It outperforms an O-360 C/S above 12,000 feet in both ROC and speed- all running very conservatively, despite being heavier and as now refined, on similar amounts of fuel. VZX may be the first auto powered RV to accomplish this and I'm proud of the results of my first attempt with only 134 cubic inches and less than $10K FF including prop.

Some of my conversion is a mess after many modifications and will be cleaned up once the -10 is done- making it lighter and faster. There were many lessons learned along the way and I'm still learning.

I'm not shooting the messenger and have learned a lot in our discussions. Please continue your good work which I hope to apply in future to both my aircraft.

BTW, we all fly on faith in single engined aircraft and some of us are bitten from time to time.
 
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So why don't you do it yourself?

Staying a bit more on the subject, I am pretty sure I am a part of Eggenfellner's history that he would like to see go away.

Once a vendor sends a product out the door it is no longer under their control and it will speak volumes about it's quality for all the world to see.

Perhaps we can call this part of the process of natural selection for vendors. It is unfortunate for all of us that there is not more competition in this field.

Randy C

Hey Randy, I'm sure that you are one of the VERY FEW having a legitimate problem with a Egg product. (Save the gearbox comments you guys, it is a minor problem that has been corrected like the Lyc crank problems.) Randy you now call the product "your own" so why don't you start producing a competitive package? Why don't all the naysayers become the competition? Because it is DIFFICULT to produce a successful package that's why. Randy, who has some legitimate gripes aside, this forum is a bunch of uninformed closed minded traditionalists who would like to cause the failure of anybody that doesn't do it "their" way. The arguements presented by many, but not all, of the posters rarely get beyond the, "My dad can beat up your dad!" level. Many of the posters are technically savy, but have never built anything themselves. By that I mean started from scratch and built something for sale as a finished product. It is a incredibly difficult process. Dan H made some progress by starting a "technical only" thread, but even there it was shown that few people could be satisfied. I found it interesting enough that I started doing some posting again. Sadly once that thread was closed and this one started to show an actual customers good will the same old arguements were made. Auto engines can't run 100% etc... "Of course that is only my OPINION." I have seen precisely 3 posters on the alternative engines forum that ever even wanted to see conversions succeed. Excluding Jan himself, who has shown a great deal of paticence by even posting here. Reduction drives can't work, they do in every helecopter ever flown, but they can't work. Gear drives can't work, of course they do in some of the most revered aircraft engines ever created. Water cooling can't work, that is just stupid. If I showed half the resistance in my engineering work and anywhere near the level of the "not invented here" attitude I would have been justifiably fired ages ago. Sorry guys if the early aircraft industry had any of the forums general attitude we would all be traveling by train now.
BFN
Bill Jepson
(properly SIGNED as mentioned by Dan)
 
Hmmmm indeed

And yet you are building/flying an "experimental" aircraft. Hmmmm. I guess you want to build/fly an experimental, but not TOO experimental. ;)

Regards,

Mark Sletten

Mark, I know a little bit about experimentation. Buying a turn-key Eggenfellner engine doesn't make more you more of an experimenter, it makes you more of a risk taker. Jan is the experimenter. :rolleyes:

A theme I see again and again is comments claiming that "no amount of data" would convince the anti auto engine people. This may be true for a very small subset of people on these threads, but most of the VAF denizens are are practical, mechanically minded people. I want as much as the next guy a cheap auto engine conversion I can fly off into the sunset with. I'm not an anti auto engine guy, heck, I've rebuilt and hot-rodded over a dozen of them, everything from Nissan 2L to Chev V8s. However, neither my considerable TLAR mechanical engineering skills nor my formal electronics engineering education would have warned me about the unique problems that can arise with PSRUs. I owe a debt to Dan H. for patiently illustrating the issues that can arise with PSRU design.

Given what I now know, I still think about putting together a RWS rotary system. I've got the skills to do it, including strain gage torsion testing if I feel its needed. As Dan has shown, it isn't that difficult or expensive. It would be a big time sink, no getting around that. The dollars saved(?) and the education that would be gained does tempt me. And Mark, this would be experimentation. :D

The Eggenfellner package may be a good value. It's just hard to tell. If I'm going to pay Lycoming prices, I'd need some assurance that I was getting near equivalent reliability, safety, TBO etc, etc. Smoothness and quick starting is not worth much sacrifice in those areas, in my opinion.
 
I think it is important to hear all sides about problems and reliability- plus the good experiences. There HAVE been a number of problems but as Bill states, these are being or have been addressed for the most part.

Randy is modifying his package to suit his needs and address things he has not had good experiences with- nothing wrong with that and I'm looking forward to hearing how it works. I was happy to advise him on some questions he had and am glad he is still pursuing Subaru power.
 
Getting Back to Eggenfellner history? (is like Lyc history?)

Air cooled engines operate at higher thermal stress levels and heads operate in a permanently annealed condition- hence their issues with cracking heads to this day. Mechanical stresses are similar on both types as has been shown before.
Ross I have to call you on that my friend. With all due respect CHT of 400F or even 500F is no where near annealing aluminum. I agree, with a CHT of 500F, red line, aluminum starts to lose strength. However most RV's keep their CHT below 400F unless under hot heavy duty. Even HOT RV's stay below 425F. I agree if you're running CHT's of 490F, you will not make TBO, no doubt about it. The oil cooks in the valve guides, leaves deposits and you get valve issues. To get back to Eggenfellner or Subaru's, water cooling is good for the engine, but adds weight, complexity and sadly with a RV tractor configuration, probably a little more cooling drag (but improvements are being made all the time in this area).

PS: The Lyc is not only air cooled it's liquid cooled, i.e., oil cooled. Oil runs around the heads and valve guides, especially the exhaust valve guides, carrying heat away, as it drains back into the crankcase. Your indicated oil temp is actually about 20F to 25F higher in the head, where oil temp is highest.

You might say, "But George the combustion gases are at 4000F?" That is true, but because of the carbon coating on the metal, built up from combustion and intentional air swirling, the metal does not really see the full temp of the gas, which is held away from the metal. The combustion process is also not continuous. It's like running your hand through a candle flame fast, no damage. Even the "burner cans" in a jet engine don't see the full temp of combustion; "air jets" are used to corral or channel the REAL hot gas in the middle of the burner away from the side walls. That is partly why jets get "spooled" up to a min RPM before the fuel is added. If you bring in fuel too soon before you have enough air, the fuel can cause a "HOT START" and actually melt the engine. Of course jets operate at much higher temps and continuously! They use exotic metals to handle this as well.

I do agree that the clones are overall better engines today than Lycoming's original design.
This is myth based on clever marketing propaganda. When Superior and ECI came out with their cylinder assemblies each was WAY better than Lyc, better still than the other. Lycoming is the onlymanufacture of the roller cam, which is the state-O-art, by the way.

Clone's are made to the exact specs as the Lyc parts! So what is better? Some clones argue they have better manufacturing or finishes. OK I'll bite there are differences there, but better? Different, yes.

Superior claims or implies they have a better steel forging process for their crankshaft. Well that is not really true, different yes but not better. They use an electric remelt process for environmental manufacturing issues, i.e., less pollution. The way Lyc forges its steel is still as good (really better), but it does pollute a little more, giving off more gases. We know there was a few years where the Lyc process fell apart and bad cranks got out. It was a few years in a +50 year production run. Stuff happens. Not good but what can you say, problem solved.

Reading sales propaganda during the early "Jug wars", they all said their jugs where better. The last joke, smooth cast v. the rougher sand cast heads. Yes some casting methods are prettier to look at but not better. In fact the pretty heads years later ended up having some services issues. The rough ones, like the OEM Lycoming jugs, where fine as always. Lyc even came up with their own "sales pitch", the rough surface was better for heat transfer and air flow. They my be right? My opinion, it does not matter, go with price AND service. They are all pretty close in price. The legacy Lyc parts are a little more, but thanks to the clones they have to be price competitive. I'm critical of one thing, casting flash left over after manufacturing, blocking critical areas of the head, causing high CHT's. Who made them and sold them this way? I don't recall, but it's unacceptable and can easly be noticed and corrected before the customer gets it.

They all (Lyc, ECI, Superior) make good products. The real issue is price (the clones have a small advantage) and customer support. Since Superior had their AD issue and they were bought by a German company, I have some small (very small) loss of confidence. To be honest never dealt with Superior. I have worked with both Lyc and ECI folks. They know what they are doing and you can get them on the phone for help and support, especially Lycoming, world wide 24/7.

Other "better stuff" like composite sumps? Nice but that was a problem; to the companies credit, they handled it as well as you can expect. Another clone says they do some "special porting" or add ridges to their sump that makes it better? OK, prove it.

Getting back to Subaru engines, they have excellent, pretty manufacturing. They can cast a 1000 blocks a day, and they all are in spec and pretty. That does not mean the Lyc is crude or out of tolerance, just low production. In fact some "Lyc" tolerances, fit and flatness requirements are as tight as you can get. Of course piston to cylinder wall, valve to guide clearances are intentionally looser, to account for higher expansions with air-cooling. Water cooling is technically better (yes Ross I wrote that). :D In fact most motorcycles, including racing dirt bikes have gone to water cooling, but in airplanes minimizing weight and aerodynamic drag are at a premium. It's that water cooling and the less mechanical "clacking" sound, pistons, valves and gears make in a water cooled engine is what makes people think its of higher quality or smoothness.

Encasing the whole engine in a water jacket no doubts dampens noise and vibrations.

Fewer motor vehicles (bikes, cars, jet ski, snowmobile), are air-cooled today. This is mostly due to pollution standards and noise standards. Water cooling allows a tighter top end, with less blow-by. The water jacket also makes the engine quieter. That is why your cars oil does not get dirty as fast as your Lycoming. Porsche finally went to water cooling for their venerable 911 in the late 90's. BMW and Harley Davidson motorcycles both made famous with their air cooled twins, both have a water cooled line of bikes as well.

Water cooling is COOL! :rolleyes: One problem is working water radiators/heat exchangers into the plane, while not causing extra drag and weight. Air frames have been optimized for air cooled engines. Also planes have plenty of air to cool usually, so any lack of efficiency is not super critical. However applications like jump plane or tow plane, water cooling I think wins in that application. Reliability of water cooling should be excellent with high quality parts and preventive maintence. Air cooling does have the advantage of not needing pumps, radiators and hoses. If they are not there, they can't fail, ever.

"If it ain't broke, don't fix it"

Again, there have been hundreds of thousands of electric props built and they work just fine unless you are doing aerobatics.
Yea I like doing aerobatics.

Like I said a Subaru 3.6 liter is like a Lycoming 6 liter except for cooling, one water the other air. They both are piston engines in the "boxer" configuration. If you strip away the electronic fuel injection and the water jacket, the Subaru is a baby Lyc in many ways. If you took all the water jackets off a Subaru and added big air cooling fins it would sound like a Lycoming.
 
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It seems clear that Zoche will never actually offer his engine for aircraft after all this time and if he does, it will be silly expensive. Deltahawk has much to prove as far as longevity and real world numbers go. WAM appears to be locked in a cottage industry loop. Thielert is a good example of a project with top notch, F1 level engineering behind it with considerable validation but not being up to snuff in the real world and really too expensive for experimental aviation. Their reputation is not off to a good start and they are now having to re-design from real world experience to fix some serious problems that the engineers did not get right the first time.

Engineering can help weed out many potential problems in a design but it is NOT a guarantee that this will be so. It will generally save time but maybe not money in the long run.

Read what David wrote. Jan's FF packages are flying quite successfully in relatively large numbers at prices many people can afford. I think many here have NO concept of what it takes to make a project like this a commercial success. Could someone take $2M and design a better FF package than Jan's? Undoubtedly but the unit costs would have to exceed $50K to ever recover the development costs at the quantities produced for this market.

Costs and QC are big factors in using off the shelf gears and shafts as opposed to having these parts custom made in low quantities. RWS does a similar thing successfully. You do an all custom PSRU with complete engineering and testing and you end up with A $12-13K piece like EPI offers. A nice piece but out of the budget for many.

I'll say this again, I'll take flight time on a system over a ton of theory any day but I'd like to see full TV tests done on the finished product as well so one can worry less about spinning things up front.

Jan's doing it. The others are just talking about it. There is a world of difference there.

I'd invite those who criticize Jan's methods to give the market a try for yourself. Better have plenty of financing in place before you start.

What are you talking about? The thielert engine is a huge success. 1500 1.7 have been sold, and more than 1200 2.0 are now produced. The 1.7 has accumulated more than 350,000 flight hours in the last 4 years. This is an average of 233 hours per engine and most of these were sold from 2006. You have to keep in mind that the engine is brand new. Neither mechanics nor pilots are used to them, so some tuning is only natural. In Europe the efficiency of the engine and fuel prices means that for each 1000 flight hours with a Thielert vs O-320, the reduced total fuel cost of the Thielert represents the value of one brand new Thielert. Flight schools simply cannot afford not using them. This is a certified aircraft engine, a modern computer-controlled turbo-diesel, a first of it's kind in aviation and simply not something that can be made without real engineering effort on all levels. Besides, good engineering is not only theory, and is not only done by people with a degree from the university.

Anyway, by reading the posts in this forum, I get the impression that Jan's engines are not really an alternative to Lycomings. They are more like a completely different product alltogether made for those specially interested in engines in general and Subaru engines especially. It seems to me that the "because we can" (get a smooth ride in a Subaru) principle is the only important point, and you really cannot argue with that :) I mean, isn't that why we all are building our airplanes in the first place? :)
 
George I stand corrected on the annealing temp. What I meant to say was that aluminum alloys lose half their tensile strength at 400-450F. OK , I looked up the actual figures in my materials handbook for 6063T6

Tensile @ temp

35ksi 68F
9ksi 400F
4.5ksi 500F
4ksi 600F

Common casting material 356T6 is also around 4ksi at 600F and these materials are hot forged at temps as low as 500F! I was wrong, at 400F you have 1/4 the tensile strength, not one half. I'll keep my heads liquid cooled.

Their is no comparison in the pressure die cast blocks produced by Fuji and a sand cast block. The Fuji parts are absolute jewels. Liquid cooled engines cannot have porosity due to exchange of oil and glycol. This has been a big problem on Porsche Boxter and GM LS engines initially to name just a few. Poor sand castings are not acceptable here. Fuji dodged that bullet and went for low pressure die castings from the start. GM had to switch vendors (to Canada) to have proper castings done.

I'd also add that some running clearances in Subarus can be as low .0004 inches- which demands very precise machining indeed. If you are off 1 or 2 tenths, the thing blows up.
 
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Jewels, have to agree

George I stand corrected on the annealing temp. What I meant to say was that aluminum alloys lose half their tensile strength at 400-450F.

Their is no comparison in the pressure die cast blocks produced by Fuji and a sand cast block. The Fuji parts are absolute jewels. Liquid cooled engines cannot have porosity due to exchange of oil and glycol. This is a has been a big problem on Porsche and GM LS engines initially. Poor sand castings are not acceptable here. Fuji dodged that bullet and went for low pressure die castings from the start.
"...half their tensile strength at 400-450F?"

Just does not sound right, but at red line, 500F yes you are half way to melting and have lost substantial strength.

I agree you should not be above 450F for long periods, per AvWeb article Pelican's Perch #18. The article features an old P&W chart of CHT verses aluminum yield tensile strength. The chart shows no issue up to 450F. Between 450-500F only allowed for short periods. This jives with Lycomings recommendation to keep CHT at or below 400F for make engine life. The notes are:

"The higher limiting temperature (500° F) is for a restricted period of time, and is confined to take-off, to maximum performance in climb and level flight, and emergencies. The temperature limit for restricted operations should, therefore, be used for the shortest possible time only, and must never be exceeded. (Lyc does not allow any +500F ops)

"The lower limiting temperature (450° F) is the maximum for continuous operation. It should never be exceeded except under the restricted operating conditions mentioned in the previous paragraph. It is sound practice to hold the cylinder head temperature 50° F (30° C) below this limit to keep the cylinder head materials at high operating strength." (The 450-50 = 400F as Lyc suggest.)

Bottom line you can run a Lyc under some of the time 450F and certainly all of the time under 400F with little fear of the engine melting. To be fair some alternative engines have temp issues as well, no doubt because of the minimization of the radiators to lower cooling drag and weight. Airplanes are a compromise. (Aluminum generically melts at about 1000F and anneals at 775F. There is fancy stuff like thermal creep and yes stress but if you follow the above limits, the Lyc should be fine.)

There is no doubt that Japan has beautiful Aluminum castings and forgings. I have owned two Subaru's and three Acura's. The manufacturing and quality amaze me; not to mention they can crank them out at a high rate with the quality. I still miss my Subaru. I am waiting for the Subaru diesel to make the North American Market, fingers crossed for next year. I don't think anyone questions the quality of Subaru engines, they are pretty and good little motors.
 
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A serious question...

Hello,

The following represents my opinion only, not that of SteinAir or any of it's subsidiaries...

Seriously... why does anybody care what anybody else does engine wise? I have an Aerosport 0-360 in my 7A. Just the engine for me. I can honestly say I don't care what anybody else does... I don't wish harm on anyone, but what makes them happy and feel safe is okey dokey with me. I don't care when someone "disses" my choice. Why should anybody? I'd suspect it is to internally rationalize one's own decision making regarding their purchase. Buy what you want and be happy. I seriously doubt that anyone's mind will be changed by this argument one way or the other... somewhat like a an argument about religon. This is similar to the tipup/slider, nosewheel thing (I'm a nosewheel/slider guy and totally fine with that, my next RV will be a taildragger). I know that that combo is the more maligned choice... do I care?? One thing I have learned in life is that nobody knows how to live my life better than me (except my wife:D) Build, fly, live....
 
What are you talking about? The thielert engine is a huge success. 1500 1.7 have been sold, and more than 1200 2.0 are now produced. The 1.7 has accumulated more than 350,000 flight hours in the last 4 years. This is an average of 233 hours per engine and most of these were sold from 2006. You have to keep in mind that the engine is brand new. Neither mechanics nor pilots are used to them, so some tuning is only natural. In Europe the efficiency of the engine and fuel prices means that for each 1000 flight hours with a Thielert vs O-320, the reduced total fuel cost of the Thielert represents the value of one brand new Thielert. Flight schools simply cannot afford not using them. This is a certified aircraft engine, a modern computer-controlled turbo-diesel, a first of it's kind in aviation and simply not something that can be made without real engineering effort on all levels. Besides, good engineering is not only theory, and is not only done by people with a degree from the university.

I disagree. The 1.7 engines are rarely if ever, making it to TBR and one flight school in the UK is now suing due to the dreadful experiences they've had with their Thielerts. I have a friend who owns a Diamond maintenance facility here 2 blocks from my shop and they also see many problems with these engines. They are hour hogs (good for them, bad for the customer and Thielert). http://www.avweb.com/avwebflash/new...sDiamondOverDiesels_196928-1.html?CMP=OTC-RSS

While the 1.7s are not failing catastrophically in most cases, serious problems with pistons and rings and extreme oil consumption is afflicting many with well under 500 hours on them.

To their credit, Thielert is paying most of the bills and applying lessons learned to the new 2.0 engines yet customers are generally unhappy with these engines. Aviation Consumer had an expose on this Dec. 2007 and you can find plenty of references to problems on the net- just type in Thielert 1.7 problems or similar. You can find other posts from Europe on various forums if you do some digging as well.

An engine which burns 35% less fuel than a Lycoming is no good if you have to fix it all the time or pull it to plug a new one it well before TBR. Some do not consider the performance to date very good for a certified engine, despite it being a new design and having had over $200M invested in the development and certification.
 
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By the way, I would love a Lexus engine, if it were designed for aircraft!

There was one. It was tested on an Aztec by Scaled composites I believe, for Toyota. It was never put into production because of the sertification requirements.

Jan
 
The Pond racer

There was one. It was tested on an Aztec by Scaled composites I believe, for Toyota. It was never put into production because of the certification requirements. Jan
Jan the other scalled composite project was thePond racer:

To power the Rutan designed plane, two 3 liter V-6 engines were chosen. The engines where based on the Nissan/Infinity VG30 automobile engine. The engines were where used in production cars and auto racing. They were turbocharged and est. to produce 1,000 hp. However, fitted to the Pond Racer, the engines only achieve a peak of around 600 hp. The engines drove 4 bladed propellers via propeller speed reduction units (PSRU).

They had a series of technical problems, especially with cooling. It was brought to Reno to race in the unlimited class. It showed promise placing 2nd in the Bronze class. However the following year, in 1993 during qualifying an oil leak developed. The engine failed, causing a crash that sadly killed pilot Rick Brickert. Current unlimited gold class winners are the large air-cooled radials. However to think the pond racer was competitive in 1993 with 6 liters is amazing, since that is the displacement of ONE 360 cu-in Lycoming.

pond.jpg

pond4.jpg
 
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Staying a bit more on the subject, I am pretty sure I am a part of Eggenfellner's history that he would like to see go away.

Once a vendor sends a product out the door it is no longer under their control and it will speak volumes about it's quality for all the world to see.


Randy C

Not at all that way. It is true that the STI engines became very complex and needed many upgrades, including the requirement of a larger gearbox. But this constituted only 25 engines of all the engines ever sold. It was not at all hidden, when the STI engines became available, that this was going to be an experiment of max possible performance. As you know, max performance can quickly turn into complexity and money. The E-6 engines now going out, 5 years later, have no resemblance to the STI 2.5 engines. An STI upgrade program has also been ongoing at the company and we get a few updated each year.

Jan
 
I hope that I didn't offend anyone by my comments. The truth is I love flying, I love flying RV'S, it wouldn't matter to me if people installed rubber bands on the front of there aircraft as long as it as safe as possible. I know, that is what we all want. We as aviators and "experimental" aviators have an up hill battle, a battle of our freedom to fly what we want and when we want to fly it. We need to make sure that what ever we use to power our aircraft is safe whether it is Lycon, Sube, or any other means, safty has to be paramount. Planes falling out of the sky is not good for any of us.
 
It is true that we see more and more specialty applications for the engines. We sell many to very cold climates where the heat from an exhaust muff just won’t do it, we sell to high altitude applications where a reliable liquid cooled turbo and cabin heat is a must, we sell to countries where auto fuel is the norm over 100LL and we sell to those that just can not see why they should adjust the mixture of a 2008 aircraft engine. We sell to modern fighter pilots and airline captains used to having a sophisticated engine management system and we sell to younger pilots, familiar with Japanese car engines.

Jan
 
I'm old and not cool

we sell to those that just can not see why they should adjust the mixture of a 2008 aircraft engine. We sell to modern fighter pilots and airline captains used to having a sophisticated engine management system and we sell to younger pilots, familiar with Japanese car engines. Jan
Gee that makes me feel bad. I'm not cool like a modern fighter pilot. :eek: I'm familiar with japanese engines. I'm only in my 40's and fly modern airliners; I want to be cool, but I still like moving the mixture knob once or twice a flight. It just not a big deal to me. I admit if my engine could run perfect mixture automatically, that would be nice. Is that what the Subaru does in a plane?

Jan, I understand you don't use the O2 sensor. I also recall reading you have dropped the mass-air or throttle position sensor? How do you maintain perfect mixture control with your EFI system?

To be fair Jan, fighters and airliners since the 60's have turbine engines, none have a mixture control. The airliner I'm familiar with has FADEC, and it does add protection and autothrottle control, which is nice. The older jets required the pilot be more careful with the thrust levers. If the work load of a mixture control knob is too much, Aerosance makes a FADEC for the Lyc, about a $8,000 premium on a new Lyc. For the few percent gain in fuel economy, power and slight reduction in work load, you pay a premium in money and complexity. I don't think is worth it, at least for the Lyc IMHO.

It's nice the Eggenfellner has that included. That is a nice selling point. :D

I am not cool; I still think old farm tractor technology, mags and mechanical FI or Carb are still cool in their own way, even if the cool kids don't like it. ha-ha :D
 
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