Intro

[Cliff Cordy]

I have been asked to write an introduction about my airplane experience. I learned to fly in the mid 70s, age approaching 40. This is too old, and I never became really comfortable flitting around in a little plane. Once I get above about 1000 feet AGL, I feel ok, but I like straight and level and smooth.

I built a Q2 from about 1982 to 1989. It was a huge job. I figured I had 2500 hours in it at first flight. During this same period, I worked full time and did the course work for my PhD. Time management is essential. First flight lasted maybe 10 seconds before the engine died. It was another 500 man hours before I cured all the reasons for that. The engine was marginal. The carb was marginal. The fuel system was marginal. It was mathematically impossible for them to work together. At full throttle, it was far too lean. I had cracked cylinders and burned heads. This happened during high speed taxi tests and 7 short hops (about 5 seconds, that revealed no problems in the fuel system). Revmaster said the engine was 9.5:1 compression ratio and accused me of modifying their engine, which was patently false. They sold me new heads, 8.5:1 compression, which turned to plastic before I resolved the fuel problem (or may have been plastic before Revmaster sent them to me).

I made a bunch of needles for the carb with more, much more, and hugely more, slope. The last one worked right. Then I bought two brand new VW heads and machined them myself. The engine hasn't missed a stroke since.

The airframe design has problems. I'm a good engineer and cured all the obvious weak spots in the design as I built the plane. The wheel fairings were obviously bad, but at that time, I didn't know how to do them right, so I built them to spec. The engine cooling is terrible, very high drag. At that time, I didn't even understand cooling drag, so I built it to spec.

I'm a good craftsman and made a smoother plane than I have seen elsewhere. I figure the engine is putting out 60 HP (2050 cc, 7.8:1 compression). I do 185 mph near sea level and 170 true at 8000 feet. Empty weight is 585 pounds, plus about 25 pounds of lead in the tail for balance. Flying alone, I (150 pounds) can typically climb about 930 ft/min near sea level. I've been to 10,000 feet, still climbing 300 ft/min. I'm convinced that if I did nothing other than make good wheel fairings and engine cooling, I could go over 200 mph. The aerodynamics of the air frame are obviously very good.

The head tank had a microscopic leak somewhere. This caused a puddle of gasoline between the main tank and the canard. My transponder antenna sticks down into the canard. Gasoline got in and disolved all the polystyrene foam in the canard. I cut into the end of the canard and filled it with polyurethane foam, that won't dissolve in gasoline. Huge job. I also removed all the fittings from the gas tank and sloshed in a glob of epoxy all over the bottom part of the head tank. That cured the leak.

About 5 years ago, I noticed the fuselage over the head tank had turned to rubber. It is hard to imagine fiberglass feeling like rubber, but it did. Gas fumes had seeped thru the fuselage skin and expanded the polyurethane foam in the glass-foam-glass sandwich. This broke all the epoxy pedestals that maintain the separation in the sandwich, which destroys most of the strength. It also turned both layers of glass to rubber, which eliminates any residual strength. Quickie didn't use the right kind of epoxy when they made the kit. I fixed that, but soon noticed the main tank was doing the same thing. I haven't fixed that.

In the last 5 years, I've put all my effort into designing my new plane. I'll probably never fix the Q2. Fabrication will start in early 2007. Conceivably, first flight could be fall 2008, but I really expect spring 2009.

That is about all of my story except to note that 1 month before the maiden flight of my Q2 (with me as pilot), I went for a ride with a friend in his Piper Pacer. He flew into the side of Mt. Hamilton, San Jose, CA, catastrophic crash, seemingly no chance for either of us to survive, and neither of us were seriously hurt. Seeing the prop stop 30 feet up on the maiden flight was seriously disturbing.

[Jon Matcho]

Glad to have you here Cliff (and still with the living) -- that's some background you have there. Too bad about your Q2, but it does seem best to move on. I'm sure you could fix it, but it would be a lot of work.

 

What kind of design are you working on?