Jerry Hey wrote:

These  Ivo prop blades cracked.  Came of a Tailwind.  This story gets
repeated so often.  How does this company stay in business?  I know a
few rotary guys are interested in Ivo's.  The question is Why?    Jerry

    Jerry,

      What engine was being used by the Tailwind? How many hours on the

    Ivo? Were the blades torqued to proper value?

    Kelly Troyer

This is a failure mode of the IVO I have not seen before. These are either
ground adjustable twist blades or they are from a variable twist configuration.
Usually IVO blades fail when used on large displacement certified aircraft engines 
due to high peak torque pulses. That is not what happened in this case. These 
blades failed from over torque ing the twist mechanism so the blades failed in 
torsion mode. In this case it had nothing to do with the type of engine.

It is not clear whether it was a stock amount of variable twist or somebody 
manually twisted them beyond the design limits.

Paul Lamar
 
 
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