On Mar 20, 2009, at 2:00 PM, Paul McAllister wrote:
> I am not an aerodynamicst, not even an amature one but I was
> wondering why you didn't think the Kiev blades will be much of an
> improvement over the Warp Drive blades.
Bud,
I too was surprised at your apparent skepticism as to whether those
Kiev blades may offer improvement over the current WD blades in the
Airmaster hub.
I had several long emails w/ Martin on the subject...perhaps 2 years
ago...and my recollection is that he was quite candid about the WD
blades being less than optimal given the flight envelope and length
limitations of the blades for the Europa. My understanding is that
the WD blade stock is much longer, and when cut down to length
required, they lose much of their twist...to such an extent I've read
that the inner portions of the blades create negative thrust under
certain conditions. I've speculated that the relative lack of twist
may be a factor in engine cooling...just speculation, I have, of
course, no direct experience.
Assuming that the "432" references a new hub, I hope it's available
with other than a Rotax flange.
Fred
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