Fred,
See my other post to Paul.
I agree about the Warp Drive Blades. Even in the longer blade lengths
it is not the best blade for altitude. I find them very good in the
7500 to 9500 foot range for our aircraft using 100 Hp engines. It is
not a perfect world. The Kiev blades appear too long also. Ergo, my
fear is the blade will be less efficient when trimmed for our plane
unless those pesky Russians remake the blades for us as you normally
can't whack a hollow blade prop to length.
Maybe VDM will make a smaller version of the Me109 blade for our use.
Anybody know them?
I never thought of myself as skeptical, just cautiously
optimistic...(Sarcastic humor through years of training though.) Bottom
line testing will tell. I'm excited about the near future, but patient.
Bud
----- Original Message -----
From: Fred Klein<mailto:fklein@orcasonline.com>
To: europa-list@matronics.com<mailto:europa-list@matronics.com>
Sent: Friday, March 20, 2009 9:12 PM
Subject: Re: Europa-List: Constant Speed Props, etc.
<fklein@orcasonline.com<mailto:fklein@orcasonline.com>>
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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