There seems to be some misconceptions about the IVO
prop. Since I own an IVO Magnum three blade prop(72"
dia. in flight adjustable from 45" to 105")I can tell
you that in the "relaxed position" the blades are in
the center of their travel at about 75". They can be
twisted both positive and negative about 30" from this
position. While their early versions did have a
tendency for the blades to shift position in the hub,
IVO has modified the hub by knurling the surfaces for
a better grip on the blades. This has apparently
solved this problem. IVO now sells an electronic
governor for $300 to convert the in flight adjustable
to a true constant speed prop.
Although my project is not quite flyable yet I have
run the engine/prop on the ground and am impressed
with its smoothness. Hope to be flying this spring.
I chose the IVO based on Dave Atkins' recommendation
(he has been flying with his for about 8 years now)and
the number of other aircraft at Oshkosh using the IVO.
I will update when I get airborne.
Jim Maher
13B/Dyke Delta JD-2 project

--- Original Message ---
From: Rick Girard <fly.ez@verizon.net>
To: "Rotary motors in aircraft"
<flyrotary@lancaironline.net>
Subject: [FlyRotary] Re: props

>Just MHO but Ivo should have made their prop so that
it twisted to
>flatten the pitch for take off and relaxed into the
cruise position. The
>rotary has enough power for most of the airframes
builders talk about
>installing it in, that a minor degradation of in
takeoff and climb could
>be offset. Let's face it, cruise performance is where
the rotary can
>make up for its high BSFC. I'd much rather go from
1000 fpm to 800 fpm
>climb than lose that 10 knots at cruise. If I do get
the cruise lose I'd
>rather it came from my hand on the throttle. I save
lots of money by
>using 65% power, our club charges by tach time.
>
>Rick Girard
>
>
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