Comments on: Motorcycle Engine Powered Airplanes

By: William Duncan

William Duncan — Wed, 24 Jun 2009 02:48:59 +0000

Well designed car engines will work fine in the GA duty cycle because that is exactly how the Germans drive their cars on the Autobahn. It also corresponds with, of all things, a school bus. Road and transit buses use heavy duty diesels, but school buses (in the US) are built on truck chassis, and before the medium duty diesels became popular, they all had big block V8 gas engines just like muscle cars, pickups, station wagons and boats.

School buses have terrible aerodynamics and on perfectly level ground use 50% or more negine power at high speeds (hence their dismal economy.) Up any hill at all it goes drastically up. I drove a schooly for our church’s music ministry for years with a rebuilt 377 (350 crank, 400 block) Chevy on propane and we would go for 30 to 60 minute intervals at 26-27″ Hg at 2600-2900 rpm in the flat lands of Nebraska and Kansas.

Dave Blanton of Wichita was the most successful engine converter, although his projects did have issues, and much of what he wrote is still true. He believed that torsional vibration was not an issue if one could start and run the engine throughout its RPM range with no propeller attached, and I suspect he was right.

By: Cooper

Cooper — Thu, 04 Jun 2009 23:58:11 +0000

Anybody recall that Porsche produced an aircraft engine in the 80’s? They were available in Mooney’s. And they were a failure. Here’s a critical look at them: http://www.seqair.com/Other/PFM/PorschePFM.html
The Lycoming/Continental designs truly are ancient [dating back to the 1930's], but they’re a known quantity.

By: Jim

Jim — Mon, 18 May 2009 00:37:31 +0000

If using a Mazda wankel in an airplane is anything like a car, the fuel consumption will be awful. Also, I don’t know whether they ever solved the tip seal problem. It’s admittedly anecdotal, but the couple of engines I had didn’t make 50,000 miles before having to be rebuilt due to tip seal leakage, which resulted in a significant compression drop. Figuring an average of 50 miles per hour, that’s 1000 hours of automobile use.

By: carl b.

carl b. — Sun, 05 Apr 2009 23:10:11 +0000

a wankel engine can be modified to be used as a 200 horsepower or split and used as a 100 horsepower engine for sport planes or experimental aircraft. The rotary plates where the rotor rotates and becomes the piston must be taken to a place where the plate can be heated to high temps and fired then cooled slowly, then the plates can be used in a very reliable wankel rotary engine.without upposing cylinders the plane is smooth and very crisp responses. the engine i,m refering to was put in a sauna ray ll and with a g-rating of 4.4 wing load we had to be careful as the engine would perform more than the plane could handle.. carl.

By: mike wolf

mike wolf — Fri, 20 Mar 2009 16:30:53 +0000

WOW, thats really cool. I have a ?. Can you use a ski-do engine on a Trik ultralight 2 seater?