I was transferred to Andrews AFB MD in 1981 working on CH-3E and UH-1N helicopters and had my Sonerai done by 1984. I flew it for about 12 years, learning all the limitations of the VW engine. I kept remembering how much I liked the construction of the Corvair engine from my dune buggy days, and bought William Wynne’s manual on converting the Corvair engine for aircraft use.
Story and photos by Fletcher Burns My name is Fletcher Burns. I grew up in Fresno CA. After graduating High School in 1975, I got into hang gliding in the Pismo Beach area. I built several VW based dune buggies, with my older brother Forrest, to haul the hang glider up to the top of the dunes. That is when I started to get interested in the Corvair engine. You could hear the Corvair powered dune buggies going down the beach, they had a sound all their own. All the rich guys had Corvairs, I was stuck with 40 hp VW engines. I finally bought a 145 cu in Corvair engine from a wrecking yard and rebuilt it. I never installed it in a dune buggy, but I did run it on the garage floor with open exhaust just to hear the sound.
Marriage and kids came along and another transfer to Edwards AFB back to my home state of CA. I was in hog heaven at Edwards! I bought a Quicksilver MX with a friend of mine and actually flew it out of my backyard in a town just north of the base. My friend had a Quickie and asked me if I’d build him a ½ VW engine for it with a set of plans he had from Morry Hummel. I built the engine for him but he sold the plane before he flew it. The engine ran nice, but shuffled a little mid range, and we never quite got it to quit leaking oil. I also built a “William Wynne’” engine while at Edwards, and that’s when the idea of a 2 cylinder Corvair engine popped in my head.
THE PLANNING As usual, I started reading what I could find about it, and all I could find was that it couldn’t be done. The problems were you would loose the oil pump, pressure relief valve, distributor, and thrust bearing. It was also believed that the case was too thin to bolt a back cover on. For several years I would think and sketch possible solutions to the problems. One solution would usually cause 2 or 3 other problems, but one by one they all eventually went away.
While I was hang gliding I also took flying lessons and got my pilot’s license in 1977. I started dreaming of building my own airplane. I read a lot of books and articles on the subject and realized I didn’t have enough knowledge, so, I went to see an Air Force recruiter and read the descriptions of all the possible career fields I could choose from. I chose aircraft sheet metal mechanic because I thought I already knew enough about VW engines from my Fletcher’s 2 cylinder engine, made from 1/3 of a 6 cylinder Corvair. dune buggies. I joined the USAF in 1978 and went to basic training in Texas, then tech. school in Illinois, where I soaked in all I could about aircraft construction. I was all set to get to my first duty station and start building something, but the Air Force in their infinite wisdom sent me to Germany for 3 years working on F-4 Phantoms. While I was in Germany I rebuilt a lot of VW engines for myself and other G.I.s. I also decided to build a Sonerai IIL when I got back to the states.
There was usually more than one solution to a problem, so I would pick the lightest way or the simplest way. I would have parts laying on towels in the living room for weeks at a time, glancing at them until an idea would pop in my head. My wife tolerated it OK. I figured out where the best place was to cut the block and a way to get 8 screws in the back of the engine to secure the back cover, then a way to bolt a VW oil pump to the back cover and get it plumbed into the main oil galleys.
ACCESSORIES The oil pump would be driven off a slot milled into the cut off end of the camshaft. The pump turns the opposite
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