snips...

Correct me if I am wrong but with Butch's LAEV prop the motor uses
juice only when the position is changed right?  I am interested in
the new AeroComposites' C/S prop.  Pricey but light and extremely
well made.  They only make electric drives for their military
contracts unfortunately. I would have to modify  their hub to adapt a
electric motor and worm drive gear.

Doug in Japan

The big advantage to the metal CS prop is the high efficiency. I have
yet to see a composite prop equal it.

Paul Lamar

You should look at the whirlwind props.
http://www.whirlwindpropellers.com/
Marc Wiese

Some of the guys racing tried them. Still not as good as metal.
Hard to beat the big bucks that Hartzel and McCauley put into R & D.
It would be best if some of the carbon fiber guys
copied exactly the the metal prop plan form, airfoil and twist.

Paul Lamar

Paul


Here is a response I got from one of the people at AeroComposites today.

Doug:
Thanks for your email.  The aerodynamic efficiency has nothing to do
with the blade material (composite, metal, wood).  What is important is
the aerodynamic shape where with our extremely strong blades we can be
thinner (less drag, more efficient).  Our customers consistently tell us
that our propellers out perform Hartzell aluminum propellers and MT wood
propellers (always).  I wouldn't recommend your trying to build your own
pitch change mechanism and adapting it to someones hub.
Thanks for your interest,
Harry

Nonsense :) Structure and supersonic (tips) aerodynamics are
interconnected at the neck.

Paul Lamar

You guys look at the Carter Copter propellers?  I think he has some
patents on some interesting designs.  He might be a crackpot, however..
:)  I don't know.

http://www.cartercopters.com/propeller_system.html



Matt-


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