Mistral Rotary Moves Closer to Certification

A step forward in what has been viewed as a stop-start development program for the Mistral rotary aircraft engine was announced today. The company says preparations are underway to begin flying the three-rotor engine on a Maule MX-7 testbed in Florida.

"We are extremely pleased with the progress that our engineering and development team has made in recent months on the G-300 engine,” said Philippe Durr, CEO of Mistral Engines. “We have the engine mounted on a Maule MX-7 flight test aircraft and it is currently undergoing ground power tests at our U.S. base in DeLand, Florida.”

In addition, the company says that alongside the flight-test program that "the engineering team is about to successfully finish the structural testing in the U.S." Engine endurance tests are also scheduled to begin in the third quarter of this year.

The relative sizes of the Mistral G-300 and the Lycoming IO-540.

“Because of our confidence that we will receive FAA type certification for the G-300 within the year, we will be accepting advanced delivery preorders for the experimental version of both the G-200 and G-300 engines beginning at AERO Friedrichshafen,” Durr said. “We are already in active talks with a number of world-class aircraft overhaul facilities about obtaining FAA Supplemental Type Certificates (STCs) for our engines on popular general aviation aircraft.”

The Mistral G-300 is a normally aspirated three-rotor, liquid-cooled engine with proprietary FADEC (full-authority digital engine control) and a gear-type prop reduction drive. The last time we had a firm price for the engine was in 2006, and that was $35,900 for the 230-hp turbocharged, two-rotor G-230TS and $31,500 for the 190-hp normally aspirated G-190 two-rotor.

For more information, visit Mistral's website.

KITPLANES Editor at Large Marc Cook has been in aviation journalism for 23 years and in magazine work for more than 25. He is a 4500-hour instrument-rated, multi-engine pilot with experience in nearly 150 types. He’s completed two kit aircraft, an Aero Designs Pulsar XP and a Glastar Sportsman 2+2.

11 Replies to “Mistral Rotary Moves Closer to Certification”

  1. Burns more fuel, is unproven, and costs almost double what a conventional engine does. These alternative engine companies need to really re-think their price structure.

  2. lOOKS LIKE 35900.00 GOOD REASONs TO get an electric motor like Raser Tech.'s and some new nano lithium batteries and really get something for your investment

  3. Actually, this engine is full FADEC, multi fuel capable and has far fewer parts than a conventional piston engine. It's lighter, quieter, and has a hell of a lot less vibration. Of course it's new. But if you compare it to the new Lycoming IE2 which is their upgrade to FADEC, I think it's going to be less expensive. I am personally sick of dealing with carburetors, magnetos, etc. from 40 years ago. I hope that this company succeeds. I looked at the engine at Oshkosh and it is really beautifully built, and you can see its Swiss roots.

  4. "Burns more fuel, is unproven, and costs almost double what a conventional engine does. These alternative engine companies need to really re-think their price structure." - WELL SAID! I would add that the price wont be "almost" a double but MORE than a double (of Lyco' equivalent..)!

    "...and has far fewer parts than a conventional piston engine. It’s lighter, quieter, and has a hell of a lot less vibration." -

    Hmmmmm..? Fewer parts? Do you know the number and complexity of electronic parts involved? One FADEC has ... approx. (say) few hundred parts (2 FADECs needed) + all the sensors and cabling, a high tech' nightmare! If you count the parts (comparing to actual Lycoming& Continentals..) you have to count ALL the parts!

    Good (sub) question: are they going to use certified aircraft quality sensors? CHECK!

    Lighter? NOPE.. The G300 is actually slightly lighter (or equivalent), compared to Lyco540 and G200 is slightly heavier than Lyco'360 or opposite (have to check?). In any case, they are not lighter!

    Smaller? NOPE! On all marketing pictures they never show the (sizy..) necessary radiators and tubing for liquid cooling. Finally all that stuff will (completely) fill the usual engine cowl of equivalent Lycoming, with a big difference: a nightmare of tubing, sensors, cabling etc.

    Quieter? NOPE! Rotary engine at 7000 rpm makes a high frequency whine very comparable to variable pitch propeler sound (set at low pitch - take off setting)

    More fuel efficient? NEGATIVE! Same fuel consumption as old Lycoming in best case. By the way, a new FADEC equiped Lycoming should beat everyone easily.

    Less vibrations? YESSSS! But well balanced Lycoming is rather smooth running engine? Is this so important?

    So where is the advantage? Multi fuel? How many small airports are equiped with car fuel pumps (<10% in Europe)? Or you plan to bring yourself, in your car, the fuel for your aircraft ? 🙁

  5. The Mistral engine is nothing more than a glorified mazda engine. The engine is not well suited to aircraft since it is heavy and longer than a conventional piston engine. This thing has been in development for over 10 years and they haven't got it going yet?

    Either there is something rediculously complicated about putting a rotary in an aircraft or the company has no plan or idea of what they are doing. After searching their website and talking to their people, it seems that 25 million dollars have been spent (wasted) on attempting to build an engine for certification. Why wouldn't the company start with an experimental line and generate an income source. Perhaps they look on the experimental guys as sub-par aviators.

    This appears to be a mute point since they have run out of money and aren't paying their bills? Any truth to this? Hopefully not.

  6. Just another update. Last year at Oshkosh, when I asked the reps from Mistral about pricing they stated that the G-200 engine was quoted as 48,000 swiss francs and the G-300 was 78 or 79,000 swiss francs. I believe that the article might have a slight marketing slant to it.

    I also heard, but had no way of confirming that the engine has failed several FAA tests.

    And to respond about the FADEC unit. The Mistral system is not truely a FADEC but an engine management system. The Mistral system does not control the propeller. You still need to use a prop lever so it is not a FADEC unit.

    Really, how hard is it to build an engine control system. Mazda has one already. Why not just reverse engineer it and make it comply with all FAA requirements?

  7. FAA requirements alone make introducing a new power plant economically impossible. Reverse engineering isn't so bad in of itself but complying with the certification process eliminates many technologies that would otherwise be quite well suited to aviation. As an A&P mechanic and a car enthusiast I can testify that the rotary engine is an excellent design for aviation. Simple in mechanical design, comparable fuel efficiency when considering engine output (not displacement),and dual ignition that has proven to be Very Reliable. No they're not Fadec yet but if the Feds would allow innovation in aviation at a reasonable time and material cost there would be. One other major advantage is they don't seize up or blow apart. Having a blown seal will generally cause it to loose power but not all. Even 40% power will provide more distance options for a safe landing. There are statistics supporting the rotary engine safety record in the experimental community. But most of all they'll run on mogas or avgas without detonation damage. Blue Skies...

  8. Well, i have flown my glasair 3 with the G300 for a year now, so i guess it's time for my 5 cents worth.
    Weight is about the same as a lycomimg, both equipped, that is. The mistral is longer, but in the case of my glasair it only makes it look A LOT better. I simply lengthened the cowling, no change at all in the center of gravity.
    It simply bolts onto the standard dynafocal engine mount, delivered with the kit.
    Plumbing and wiring nightmare? No sir, the engine comes with wiring and hardware, literally install-plug-play. Cooling needs to be arranged like on any engine, the only difference is that here you use radiators. And it works well, the only difference is that in descents you don't have to look at the temperatures with any fears of cracking a cilynder.
    Fuel burn is a measured 51 liters per hour on my 300 hp engine. I do take two jerrycans in my car, each time i go to the airport, and it's well worth the money saved.
    The engine inspires confidence with the power, smoothness, and there is almost no maintenance to be done especially if you burn car gas only, as that keeps the engine cleaner.
    The noise is an issue. The airplane sounds like a formula 1 car at full revs. Mistral is only starting to adress this problem, but a solution should be found fairly quickly.
    In my experince, the engine operation is easy and very reliable. The only thing mistral needs to change is the way engine data are displayed, not that it's badly displayed, but pilots are a group of creatures of habit, and displaying data in the way pilots are used to seeing it will help in selling the engines.
    Mistral gives a lot of attention to safety, and you can see it in the redundancies in the engine system.
    The thing that realy has me sold on this engine are the people of mistral themselves. Whenever you gave a question, doubt or problem, they are there with honest answers ( even if the answer is not what you had hoped for), and imediate action to help you progress with building or flying.
    Thinking about building an SQ2 now, and there is no doubt, it will be mistral equipped.
    Happy flying
    Paul janssens

  9. Question for Paul Janssens - Do you know the name, email address or phone number of the gentleman in Santa Barbara, California that installed a Mistral engine in a kitplane sometime between 2007 and 2010. Also, do you know what has happened with the Mistral company in Geneva. I found an email address for Philippe Durr, (who is now working for another company), and reached-out to him but he has not replied. Lastly, please reach me on: alex.major@greenflight.org
    Over and out for now,
    Alex Major

  10. I have a 1975 bellanca super viking 17-31a it has a io 540 lycoming and requires a top overhaul (new cylinders,new cam, lifters and mags done and some other parts) .
    I am considering the mazda 20b twin turbo ( factory engine) has anyone tried this engine , mainly because the turbos would help keep power up at higher altitudes ?
    Has anyone used a rotor engine of 300 hp in a viking or similar plane?
    Some of the 20b engines have an aluminum casing as well ,which saves on weight.they also use better apex seals .
    I would appreciate any info?
    I don't know how much is done on FAA approval ?
    If I put this engine (20b rotary) in my plane how would this classify the plane ? I'm looking for research and users.

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