REFLECTOR: IVO Props

[Chuck]

I know Ivo will sell you a prop for Lyc 6's because I have one, and recently 
bought parts for it. I'm not aware of any insurance problem with an IVO prop 
when I've renewed my policy.

He won't sell you parts for a Lyc 4 cylinder because of a V crash several 
years ago. The owner who had lots of "help" building his plane later had a 
problem with the pitch motor, so he dismantled the prop enroute. Instead of 
following the tightening sequence (4 retightenings over a couple hours) 
which is absolutely critical (and well known), he was in a hurry and took 
off with his family onboard. Shortly afterward he started getting a 
vibration and advised the tower that he would see if it would go away 
instead of landing imediately. The blades separated from the hub and all 
perished. There was speculation that the powerful firing pulses every 180 
degrees of the 4 cyl. causes too much load for the clamping strength of the 
IVO, but there are other V's that have successfully used an IVO on their Lyc 
4's for a long time.

An Ivo is a less expensive (< $4K) in-flight adjustable pitch prop that 
works on twisting the carbon fiber reinforced blades to change pitch. Some 
people have said that this is not an efficient way to change pitch, but it 
does work. The blades are very strong and seem to work well in a pusher 
configuration. He has been making props for a long time particularly for 
ultralights.

I'm sure some of the Franklin guys can tell us what they think of their 
IVO's.




> HYTEC45 at aol.com wrote:
>
> ?
> ?
> Ivo had such a problem with the Lyc 4's that he just "gave up", 
> understandable.? However, with the right R&D the Ivo (or Ivo design) could 
> probably work on the Lyc 6's.? The Ivo have worked on the Franklins which 
> are 6 cylinders.?
> I suspect it's an insurance issue.? I raised the question of 6 cyl Lyc and 
> they said would refuse to sell the IVO for any Lyc.
> John