The Corvair Powered Zenair 601XL
May 13, 2004
Here's Our Corvair powered Zenair 601XL taildragger climbing out for its first flight May 12, 2004. If you'd like to
see a short movie, click on the photo above. (Visit QuickTime to download the movie player.)
We first saw this kit at Oshkosh 2003. Grace Ellen and I decided to
buy it shortly thereafter, and Dave Vargesko and I picked it up in the middle of October 2003. Although we made
a little progress on it last year, moving hangars in December and teaching Corvair College #5 in California
Jan. 17-18, 2004, really kept us from digging into the work until the last week in January. The airplane was
done by the first of April (an FAA paperwork glitch kept us on the ground till this week). I really doubt we
have more than 90 working days into building the airplane. Although we're professionals, keep in mind that we
had our regular work to do here, and most of the 90 days was spent developing and building tooling for the
Corvair engine installation for the 601. I firmly believe that any first timer who wanted to build this kit could do so
in six months of part time work. My hat's off to Zenair. This is an excellent kit from a first class company.
Our In-House Test Pilot Kernal Gus Warren flys the pattern, above, during the first flight.
Gus executes a perfect first landing under the watchful eyes of the FlyCorvair.com Hangar Gang in the photo above.
Congratulating Gus on a successful first flight is the entire FlyCorvair.com Crew. From left, standing above,
are Dave "The Bear" Vargesko, Kevin "The Mangler" Fahy, A&P Steve Upson, myself, and happiest to see him, in front,
Gus Warren, getting ready May 13, 2004, for the second flight, above. Steve Upson and I
were installing an optical tachometer to corroborate the tach in the panel. Whobiscat kept attacking the
new bracket from in front of the canopy.
Above is a view of the Prop-Tach successfully installed.
We reset the prop pitch higher for the second flight, above. But the airplane still exhibited a very sharp
climb rate. It would have easily cleared a 100 foot obstacle by the 800' or 900' foot mark on the runway.
As on the first flight, this is without partial flaps, or any short field technique.
Gus executes a low level pass in the two photos above and the one below. The second flight was about a half
hour. The airplane is just beginning to get tuned in. Straight and level, the plane did 130mph at 23" MAP and
2700rpm. This is a low cruise power setting. Keep in mind, the plane has 6x6 tires, no gear leg
fairings, no wheel pants, etc. This type of speed early on and Gus' very positive comments about the handling qualities of the
plane are very satisfying at the end of the building process.
Two more highlights from the second flight are pictured above and below. Many people do not realize that the XL model
has a slightly forward swept wing, which is also tapered. Its planform is apparent in many of these photos.
At no time during the flights did the CHT exceed 250F. This is really too cool, and I'm going to slightly reduce the
inlet size pending further testing. This demonstrates the excellent cooling of the Corvair engine in a simple
installation. If you follow automotive conversions, you know that many of the smaller, highly stressed engines
have difficulty cooling themselves.
Gus executes another picture perfect landing today, in the photos above and below. Gus' comment on the approach
and touchdown was that the plane was extremely stable on final with half flaps, and it handled the crosswind at
our airport very well. He rated it as docile for a taildragger.
We'll continue to update the 601 Pages of www.FlyCorvair.com as we gather more data, and fly off the test time.
Look for detailed engine installation photos in the April installment, which we'll fill in soon.
If you have any questions, please feel free to call or write.