EPS Files For Bankruptcy


Wisconsin-based aviation engine developer Engineered Propulsion Systems (EPS) has filed for Chapter 11 bankruptcy. According to a petition submitted to the Western District of Wisconsin bankruptcy court on July 29, “there are currently no investors willing to continue to support the ongoing operations of the Company outside of a restructuring process” and it is “at imminent risk of running out of cash and ceasing operations.” The company has been developing the general aviation oriented clean-sheet Graflight V-8 engine, which it introduced in 2010.

The 320- to 450-HP Graflight V-8 is a 4.3L flat vee capable of operating on diesel, jet fuel and kerosene. Engine features include an electronic control system and common rail fuel system, one electronic and three mechanical vibration control mechanisms, steel crank case and pistons, and single-lever operation. The Graflight V-8 flew for the first time in May 2014 and EPS debuted the production model at Aero Friedrichshafen in April 2019. As previously reported by AVweb, the company announced last year that it was in the process of conducting environmental and block testing for type certification credit on the engine.

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  1. ok is anyone surprised by this? they introduced it in 2010 and had first flight in 2014. that means they have been in operation for at least 10 years and have been testing for 6 years without any revenue. lets say you have 5 employees at an average salary and benefits of $100,000 which is quite low for engineers that would be $5mil just in salary and my guess is that it is quite a bit more. then you have hardware and equipment purchase cost, office/testing space, testing cost etc. at this point you have spent tens of millions without any revenue in sight for a product that might sell a couple of hundred a year if it is really successful. I can only see anything like this being funded if you are a very rich man wanting a hobby. If you are investing to make money there are far less risky options with far better potential yields.

    • You hit the nail on the head for why aviation companies rarely last. A huge amount of money is required for what is likely little to no return. People invest in aviation companies because they have a love of aviation and want to see it last, not to get rich.

  2. This is sad. I was hopeful that they would succeed. With the EPA and various tree-huggers working hard every day to eliminate 100LL this was my “plan b” power plant replacement for a TU-206. The only other option is $500k. No wonder piston GA is using 1930’s power plant technology.

  3. building a company even with revolutionary technology is a daunting task. just look at Eclipse or Icon. Eclipse could not meet the specs they originally set thus while they built an aircraft it was 1 1/2 times as heavy and finally cost 2.5 million instead of $700,000

    startups of this kind face serious obstacles.

    EPS did a great technical job. the data sheet I saw in OSH in 2012 or so is still valid and the engine they are demonstrating is the same weight, has better fuel economy, and puts out more power. If I get in my aerostar I will go twice as far on the same fuel or go 20 knots faster 1 1/2 times as far on the same fuel a totally different aircraft.

    However it has been much more difficult to get everything done than they planned for and they did not act to make sure they had the relationships with investors so when things did not go right they could not get more $
    They succeeded spectacularly in the technical challenge but the normal business problems resulting from a startup of this type did them in.

    If we can keep the technology from going to China (see some of the other articles on the web) and it gets picked up by a company with deep enough pockets to afford to spend the money to get it into production we will have a dramatic improvement in capability of our heavy single and twin fleet.

  4. It will take deep pockets to get to production. The best estimate I have is that it will take as much money as they already have invested. Thus it will take $60,000,000 or more plus r the purchase price to get into break even (financially) production. Certification will come before that but building a manufacturing capability takes time and money.

    However I think the market for this engine is still viable for about 5000 engines a year at about $150,000 each retail. a really good market. one that will be very profitable as the increase in cost can be easily made up in much of the world in 500 to 1000 hours of fuel cost savings.

  5. William 5000 engines a year for what? total piston certified aircraft sales last year for US manufacturers was 1324 in 2018 it was 1137. turboprops only add another 500-600. for all sizes of aircraft. This engine would have to be the only engine put in every small aircraft manufactured world wide to come close to 5000 and I don’t think you would get there. if you look at sales of aircraft that would fit this engine the numbers would be closer to 200-300 engines a year and that is if you add in retrofits of old aircraft as well. the commercial market has moved on to turboprops and the private aircraft market just can’t afford aircraft with engines this expensive.

  6. $60 million dollar investment including grants backed by the Air Force with the Chinese being a “stalking horse” in the bankruptcy proceedings attempting to be the low bidder, the only bidder. Left unchecked the Chinese are buying $60 million dollars and 12+ years worth of engineering, design, and certification, for pennies on the dollar. Yeah, there is a lot of skulduggery left to be investigated in this story. It appears on the surface as just another failed new-fangle American aviation endeavor. Far more to it than just that!

  7. This was discouraging news. From everything I’ve read and everyone I’ve talked to that’s involved in this project, it sounds like Fuchs and Weinzierl hit the nail squarely on the head from a technology standpoint. But like a lot of engineers, they didn’t realize how the costs would escalate when the bureaucrats took control of the schedule. And while I too am a little skeptical of a market for 5000 engines a year, I also think that this engine would be a good alternative for practically any airframe powered by a TIO 540, or TSIO 520/550. There’s still a lot of TIO 540 and TSIO 520 powered twins out there. Not to mention the R44s, the Tecnam 2012, and whatever the military had in mind. So maybe William’s projection of 5000 engines a year isn’t that far off.
    Ah well. With the 915is, Rotax is only another set of cylinders away from having a 21st century engine that will be able to power over 50% of the single engine fleet. I know, I know, they tried that with the V6 and almost bankrupted themselves. But we need to maintain some hope for the future of GA.