A Little Eggenfellner History

[janeggenfellner]

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

[janeggenfellner]

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

[f1rocket]

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.

[Adam]

Originally Posted by janeggenfellner

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

But for how long? Any long term data!

[gmcjetpilot]

Originally Posted by janeggenfellner

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. 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.

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.

[janeggenfellner]

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

[janeggenfellner]

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

[janeggenfellner]

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

[IowaRV9Dreamer]

Originally Posted by f1rocket

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.

[rv6ejguy]

Originally Posted by gmcjetpilot

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...