<VV> Re: engines for airplanes

[Rad Davis]

Mark's engine, as he would probably agree, was a great experiment.  It 
turned out that he went a little too far for the structural limits of the 
parts combination he was using.  They call them experimental aircraft for a 
reason.  He did a masterful job of dealing with the inflight engine failure.

He was running a 3100 CC setup with the VW type 4 jugs.  And he was running 
it right at the torque peak.  Turned out that the increased torque, in 
combination with having a 50" + diameter propeller hanging where the 
flywheel goes, an unknown prop hub indexing situation, and unknown harmonic 
issues, was more than the late crank could handle.

Mark has since put together an engine very close to  The William Wynne 
default specs and is putting lots of hours on the airplane with no drama at 
all.  William put a truly silly number of hours on his Pietenpol AirCamper 
with a Corvair engine in it and did a great job of proving that it was a 
simple, durable engine quite capable of making 100 HP as long as you might 
want.  The current crop of new Corvaircrafters (as they seem to be known) 
seem to have more people who want to fly fast composite airplanes, and want 
more power to do it with.  They're finding structural limits that William 
didn't with his low and slow 100 HP combination.

He has responded by building a Zenith 601 aircraft, which is an aluminum 
sportplane.  It's a much better testbed for the "fast glass" crowd.

Mark's a meticulous experimenter.  It's actually really good for everybody 
else that the crank failure happened to him, instead of J. Random 
Flybynight, because he documented everything carefully.


At 09:12 AM 3/25/2006 -0600, Roger Gault wrote:
>If you guys want to see what kind of work some of these folks do, look at
>the engine work sections of Mark Langford's site
>http://home.hiwaay.net/~langford/corvair/index.html
>
>Don't miss the "Broken Crank" section - very interesting (and exciting for
>us ex-pilots).
>
>Roger
>

__________________________________________________________________________
Rad Davis:                                        rad.davis at comcast.net
Corvairs--65, 66 Corsa coupes, '65 'brier Deluxe   http://www.corvair.org/
Keeper of the Forward Control Corvair Primer: 
http://www.mindspring.com/~corvair/fc1.html
"We did Nebraska in seven minutes today. I think that's probably the best 
way to do Nebraska."                            --Brian Shul, _Sled Driver_