Al Gietzen wrote:

Paul;

If you use this prop on a high speed airplane as is you will run into a
brick wall somewhere around 180 to 190 MPH.

Of course you're right about the pitch distribution on the IVO, but you may
have overstated a little.  From Lancair and Glassair drivers I have talked
to; I think the 'brick wall' is probably more like 180 to 190 Knots (a
Glassair reported 220-230 MPH).  The higher velocity at the tip helps
overcome some of that negative angle of attack on the inside.

Twisting the blades on this prop does little or no good<

Also, users find that twisting the blade does quite a lot of good in
reducing takeoff roll over fixed pitch, and as good as variable pitch.

Al Gietzen

Al, Please call the guy up with the Glassair and tell him to get on down to
Sun & Fun and enter the Sun 100 cross country race.  If he goes over 210 MPH 
in the Sun 100 with an IVO prop I will personally give him a check for $100. 
If he enters the race and doesn't go over 210 MPH he must give me a check for 
$100. :-) I will check all the race planes and see if anyone is running
an IVO prop. When the flag drops the BS stops!

Paul Lamar
 
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