Dan,

The newer IVO's have knurled plates which hold the prop blades
better and I did not notice any aluminum bushings in blades, just
composite hard core stuff. I have over 10 hours and do not have
to retighten after third time. There are successfull higher power
installations of the IVO prop - see
http://www.lavoiegraphics.com/velocityrg/
and http://www.ida.net/biz/arlfrd/

My concern at this time is if the high speed performance is an issue.

(Dan Thomas) wrote in message . com...
The IVO has aluminum bushings in each prop blade for the bolts, and
the plates are supposed to clamp these bushings tightly. We had an IVO
on a Soob conversion and had trouble with blade movement no matter
what torque we used on those bolts. There was fretting evident on the
bushing ends and plates, and the aluminum tape across the blade joints
(which is supposed to betray any movement) did not break. We couldn't
get the prop balanced, either, since the small amount of chordwise
blade swing on the bolts before tightening resulted in a chordwise
imbalance after tightening. We spent time fooling with getting the
blades to sit in the right spots, but it was a waste.
The blades are mostly high-density foam with a carbon-fiber skin.
Therefore, the bushings are buried mostly in foam. The skin is really
thin. I'm amazed that more of these props don't fail.
As you mentioned, the blades are twisted to change pitch, and the
outer half or so is all that changes. Therefore, the inner prop blade
is running at a negative angle of attack at high speeds, contributing
drag instead of thrust.
Surely there are better options.

Dan

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