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Where is all the Rotary love?

TheLoneGunman

I'm New Here
I used to drive a Mazda RX-8 and fell in love with that powerplant, and when I look back at old posts in forums it seems I'm not alone, or at least I wasn't until about 2008...

Does anyone still do Mazda rotary aircraft conversions, or better yet a complete FWF kit? All the websites I've found look like they have been defunct for years, or have removed any mention of doing aircraft engines. Even RotaryAviation.com, the home of Tracy Crook's famous PSRU, doesn't appear to sell it anymore. What happened?

To be clear, there seems to be a fair bit of info out there on how I myself could do a conversion, but I think that is well beyond the scope of my abilities and would still be a recipe for a decade spent tinkering in a garage. I love the idea of a rotary, but I'd rather fly behind a Lycoming than not fly at all.

Even in terms of non-Mazda rotary engines, Mistral seems to be the only game in town, and I can't find any info on how much something like their G-200 would cost, if it's even available.
 
We have an RV-7A in our RV Builders Group here in North Alabama that has a Mazda rotary engine. I'm not sure which Mazda engine it is. He has run the engine, but he has not finished the airframe yet. Stay tuned. I can't remember his last name. My impression is that he has put a lot of time into his project so far. Will tell you more when I know more.
 
Years ago I purchased a totaled RX8 to get the engine for my project. (I'm in the business). At that time there were several in the rotary camp. After lengthy conversations with Tracy and a few of the converts, I decided to sell the 13B and part the car out. Tracy gave me some great advice in that if you enjoyed to "tinker" constantly on the conversion then do it, but if you were looking for a "turn key" conversion then it wasn't the right time. Seeing that I was building my flying carpet and didn't want to reinvent the wheel, or at least my concern to build and try something unconventional, I opted out. Now this was at the time when all the automotive conversion companies were big. Not real sure if they are even around. I even looked into the Jabiru 3300 at the time seeing they had a conversion kit for the 7. I don't have a problem on experimenting on certain things in aviation but I'm not ready for the auto conversion team just yet.
 
There is an aviation conversion rotary engine site maintained by a gentleman by the name of Paul Lamar at http://www.rotaryeng.net

I believe there is a PSRU that is available in lieu of the Tracy Cook version designed by Randy Kempf according to that site. I have no personal experience, but I pass this info along
 
There's also another email list at
http://www.flyrotary.com/

If you have trouble subscribing, PM me & I'll try to get a message to the administrator.

Not as active as Lamar's list, but more who are actually flying.

Heads up on Lamar's 'new' redrive he's pitching: He freely says it's a copy of the old Ross drive, which had issues forcing Tracy to design his own to get a reliable drive. If you have a lot of experience with the cars, you should be able to sort a lot of the wheat from the chaff.

There are rumors that a couple of other individuals are looking at reproducing Tracy's design, but no one's gone public with an offer yet.

The Flyrotary group tries to get together at least once a year. The last couple of years, here at Slobovia. We're planning on doing another flyin here, probably in early fall.

Feel free to contact me directly if you want more detailed info.

Charlie
Slobovia Outernational (MS71)
edit: Slobovia is just north of Jackson MS, USA
Flying Lyc powered -4
RV-7 Renesis FWF in progress
 
My business partner has a rotary powered -6A and was the second rotary to fly, missing the honor of first to Tracy Crook by a few weeks.

We recently had this same discussion and his theory is twofold, once Mazda announced they were going to stop producing the engine, people stopped looking at them for conversion. Second, Tracy retired and handed over his business to the Cozy Girrrls. My partner mentioned that the Cozy Girrls are not making Tracy?s PRU, so that is a bit of a challenge.

This site may not be your best bet for alternative engines as some of the members have been rather hostile towards them so many who have gone down that path look elsewhere. (Part of that may have to do with the bad reputation a certain Subaru conversion developed.)

As mentioned above, my friend tells everyone who asks about the rotary, ?If you want to fly, put a Lycoming in your plane. If you want to tinker, put in an auto conversion.?
 
Cozy Girls may have retired also, the web site is still up but contact link is missing.

I knew them some years back, their products were excellent.
 
There are a relative handful which have been flying well for years with most issues and bugs worked out over time demonstrating that they can indeed do the job.

There is a rabid following on Paul Lamar's site however many of these people will never complete the aircraft with Wankel power and I often wonder why so many drink the Kool-Aid on that site since Paul has never even flown a Wankel powered aircraft he built after all these years of dissing piston powered aircraft with his unique personality.

I researched about a dozen Wankel powered aircraft last year which first flew years ago and most of them only accumulated less than 100 hours before becoming virtual hangar queens. The initial faith in the concept often seems to be worn down by reality, problems and failures. In many cases, it was hard to find any evidence that these aircraft were still flying at all with Wankels.

Like any auto conversion, they can be made to work well as Tracy Crook demonstrated with many hundreds of hours. People going down this path should follow a proven recipe like his, not the opinions of someone who has zero hours and experience in one.

The Powersport RV8s with professionally developed PSRUs, years back showed good performance when tested at Van's but were unfortunately lost in accidents.

When you are doing your own FF development, every detail has to be right or something may bite you hard. After a few good scares, many people will choose to go down the well trodden path of the Lycoming before they really hurt themselves.
 
Thanks for the replies guys, I really appreciate it. I'm still quite a ways from needing a powerplant yet but I pretty much figured the kind of things that I'm hearing here. For simplicity's sake I'll probably end up just getting a Lycoming. I guess there's just a part of me that loves experimental things, and doing things the hard way ;)

Ross, your signature says you've got a Marcotte PSRU. He's down in my neck of the woods (more or less), I wonder if he's still in business. His website says he does Mazda Rotaries, but it looks like he stopped updating his website in 2013.

I think part of my problem might be that I'm a relatively young man, and when I see a poorly maintained website that says to me "closed for business", when in fact they may just be savvier about planes than they are about web design. If you had asked me if rotaryeng.net was still around I would have said based on the web design and earthlink email address that it had been abandoned sometime in the late 90s...

Bill, I had seen some of SHIPCHIEF's old threads and I was wondering about just that! There seem to be a few guys who had rotaries installed who went back to Lycomings a few years or a couple hundred hours later. That doesn't say great things to me about the whole endeavour. Rotary lovers boast about the great reliability and super cheap maintenance/overhaul costs, but those points are kind of moot if you rip the whole thing out after 200 hours!
 
I believe that the lack of success in *any* alternative engine has more to do with the installer/builder than the engine.

My Theory: The persons most willing to try an alt engine install are typically the least qualified for the task, and the persons most qualified are the least likely to give it a shot. The exceptions are people like Ross, and Tracy Crook; people with engineering training or expertise that also have a strong drive to experiment and the tenacity to work through all the development issues. (Building an RV is an experiment in name only; it's basically metal IKEA, now.) The rest of us don't know enough to really grasp the development difficulties, and when confronted by them, most of us (but not me, yet...) give up and go Lyc.

Ross, there are quite a few rotaries actively flying that have hundreds of hours. You just won't find most of them on Lamar's site, because anyone who disagrees with him gets booted off his list.

Bill, I think that your partner Ed (tell him 'Hi' for me) probably meant that if you want to *only* fly, buy a Lyc. IIRC, he accumulated hundreds of hours in the air in his 6A before medical issues stopped him. There's obviously more 'tinkering' with an alt engine than a Lyc, but that's experimenting. There's more 'tinkering' with an RV than a Cessna, too, if you build it yourself. :)

Charlie
 
I built a turbo rotary power plant for my RV-8 and flew it for 16 hours.
I enjoyed the development, much of what RV6guy and RV7Charlie says are true.
I never was comfortable with it, because this type of project requires continuous inspection. After every flight, the cowl comes off for inspection, at least for more than the 16 hours I flew it.
I actually had very few problems, and no power failures, but there were coolant leaks, exhaust leaks, high exhaust temps, lean running on descent to final approach (stuttering) Turbocharger replacement due to incorrect selection. Later high exhaust temps and incorrect turbo insulation overheated the 2nd turbo's housing.
All of these adventures (and more) reduced the flying availability of the airframe, and limited flight to exercises in engine tuning and testing. This slowed the airframe development portion of the 40 hour Phase 1 test.
I removed the rotary power unit from the stock RV-8 airframe, it's sitting on my hangar floor, complete. I'm not sure what I'll do with it, maybe part out the mount, reduction gear, custom fabricated manifolds, and Real World Solutions engine control computer and engine monitor. The engine I keep. I still think it's great I'll find another job for it.
 
I can?t remember any rotary engine failures that were actually the engine itself. Builder engineered support systems are another story. RWS PSRU?s that are operated within the design range are holding up very well. You have to be very persistent and willing to work through all the small issues or its best not to start. It?s easy to underestimate the effort required. I certainly did but I?m also enjoying the tinkering and making small improvements. That said I?m still loving my Rotary RV10. I?m very fortunate to have two other flying rotary power aircraft here in Austin TX. I have the least number of hours at 223. The Lancair ES should be over 350 and the RV7 should be north of 600.
Ross I?m still working on relocating my heat exchanger to the belly and shamelessly copied your basic design. I hope to have time to do the installation this fall. I?ve been traveling for business so much the last year that I hate to take the plane down when I?m home and have a chance to actually fly.

Bobby Hughes
 
Quinton,
Talk to Dave Leonard ("Rodoc" here on the forums http://www.vansairforce.com/community/member.php?u=8652). He has a Mazda rotary RV-6 that has quite a few hours on it (and had it's share of teething problems, too). He doesn't get on the forums much, so sending him an email might be better than a PM. I can PM you an email address if you need it, but try the email link in his profile first. Dave will shoot straight with you, and has no problem discussing the problems he had...most of which were due to inadequate cooling.

It can be done, but as much as I too love the rotary, the saying is there for a reason....if you want to fly, go Lycoming. If you like to tinker, go with an alternate.
 
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Ross, your signature says you've got a Marcotte PSRU. He's down in my neck of the woods (more or less), I wonder if he's still in business. His website says he does Mazda Rotaries, but it looks like he stopped updating his website in 2013.

Guy Marcotte is semi retired but still doing some work on redrives. His website and customer communication have never been his strong point but he is a savvy and friendly/ passionate fellow if you can talk to him.
 
Ross, there are quite a few rotaries actively flying that have hundreds of hours. You just won't find most of them on Lamar's site, because anyone who disagrees with him gets booted off his list.

Charlie

I've known of Paul Lamar for something like 15 years and exchanged a number of emails with him over the years- or rather he took it upon himself to tell me I didn't know what I was doing usually.

Most people actually flying Wankels have little use for PL and his advice or website. I've helped a number of actual fliers over the years with turbo matching, cooling and injection advice and am pretty aware of the high timers out there but they are a tiny fraction compared to something like the Subaru fliers who number in the thousands worldwide.
 
That's not really that surprising. Rotaries are fringe even in the automotive world. Take a smaller community like aviation and you're left with few enough people you can probably name them all...
 
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