Long-EZ Bird Strike

I am working off dim memories here, but ISTR that Klaus had vibration
problems with an experimental (in the deepest sense of the word)
3-bladed prop and that he recommended 2-blades only for the EZ series
aircraft.

Many pushers now use 3 bladed composite props. The most popular for the
180 HP and up crowd is the Catto Prop, maple laminate core with 25 to 36
layers of fiberglass over the wood with a 1/2" aluminum mounting plate
embedded on one side. He makes them for 100 to 600 HP engines. They
are known to be bullet proof.

The lower power pushers use 2 blades because they can get away with it
and they are much cheaper than 3 bladed fixed pitch props. The higher
the engine HP the more blade you need. A two bladed prop on a 200 HP
engine is just to long for a pusher, so 3 blades are required.

Scott

The prop in question is an old style Performance Prop. It does have
many laminations. About 24 I think, I have one hanging from the roof of
my study. Its safest there. They no longer wrap the out portion of the
blade as it has caused problems. If its gonna break it will right there.

Scott

Corky Scott wrote:
On Tue, 28 Jun 2005 18:52:56 -0700, Ron Wanttaja
wrote:


Hi Ron, I wonder what the evidence is that it was a bird strike? I don't
see any blood and guts anywhere.

I noticed that, too. Something else could have gone through the blade, but I
don't know if a bolt or nut would do this kind of damage. The guy may have
cleaned it off already....

Ron Wanttaja


Here's another couple of data points: The prop appears to be made
from a solid blank, not laminated from numerous strips.

I read a long time ago that the props on the EZ type aircraft run in
such turbulence that it's recommended they use wooden props only. The
turbulence is unavoidable in that it's the result of the prop passing
through the lift created by the trailing edge of the wing. There also
may be exhaust pulses to whap through as well. That's why the EZ's
have that characteristic buzz when they fly by. In fact all pushers
seem to sound that way.

Wooden props are supposed to **DAMPEN** vibration.

Interestingly, the only part of the information suggesting a bird
strike is the title. Nothing in the storyline claims that or suggests
it. It certainly isn't impossible for birds to be at 9,500, just a
lot less likely than closer to the ground. It isn't migration time...

Corky Scott

Corky

The pusher prop/engine on the 0-2/337 didn't have any problems that I
was ever aware of. Nothing in Pilots Handbook. Aluminum props on both
front and rear engines.

Rear prop was in wing turblance, exhaust, etc.

Biggest problem was on gravel strips and nicks.

Big John
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On Wed, 29 Jun 2005 10:50:48 -0400, Corky Scott
wrote:

On Tue, 28 Jun 2005 18:52:56 -0700, Ron Wanttaja
wrote:

Hi Ron, I wonder what the evidence is that it was a bird strike? I don't
see any blood and guts anywhere.

I noticed that, too. Something else could have gone through the blade, but I
don't know if a bolt or nut would do this kind of damage. The guy may have
cleaned it off already....

Ron Wanttaja

Here's another couple of data points: The prop appears to be made
from a solid blank, not laminated from numerous strips.

I read a long time ago that the props on the EZ type aircraft run in
such turbulence that it's recommended they use wooden props only. The
turbulence is unavoidable in that it's the result of the prop passing
through the lift created by the trailing edge of the wing. There also
may be exhaust pulses to whap through as well. That's why the EZ's
have that characteristic buzz when they fly by. In fact all pushers
seem to sound that way.

Wooden props are supposed to **DAMPEN** vibration.

Interestingly, the only part of the information suggesting a bird
strike is the title. Nothing in the storyline claims that or suggests
it. It certainly isn't impossible for birds to be at 9,500, just a
lot less likely than closer to the ground. It isn't migration time...

Corky Scott