As some of you know, I have been working on a cowling for the Corvair converted KRs. This new cowling will allow the use of William Wynne's front starter kit and eliminate the need for any prop extention. I would encourage anyone using the Corvair to use this cowling or build your own, or modify the Langford cowl in such a way as to eliminate any prop extension. The accident of Bob Lester's happened because of a broken crankshaft. Against better judgment, he had a 4" prop extension on the hub. When he installed the hub, some loctite was on the surface and caused an out-of-round sitiation of .050 at the hub! This causes a serious wobble to the prop and crank and over time weakened the crank. This is our prognosis so far. To date, no Corvair engine has had a crank failure using the WW prop hub or any other short hub designed since the 1960's. The extra inches exaggerate any problems with prop balance, spinner, or installation those forces are sent to the crank. The Corvair vs. VW crank failure rate is still enviable but as a corvair KR pilot, I will be installing the new cowl and front starter as soon as they leave the mold. I figure I have about 20 hours of flying before then and will be doing so at high altiitude with lots of options. I love the corvair conversion but like any other engine you learn its weak links and the adjust accordingly. Build sensibly and safely.
N41768 175 hours and counting......Flying to Tennessee tomorrow and then maybe on the see Mark Langford. Still having fun. The Gathering is coming! Bill
