"Corky Scott" wrote in message
...
On Wed, 31 Mar 2004 19:51:59 GMT, "x" wrote:

Anyone care to comment on using one of MT's composite blade props with
electric pitch control?

Eggenfellner seems to really want you to use this prop with his Subaru
setup.

I'm a bit concerned both with a composite prop and an electric pitch
control.


I don't think there's anything wrong with a properly made composite
prop, and MT is one of better known prop manufacturers. They make
LOTS of props, many of them for certified airplanes.

What's your specific concern?

Corky Scott

I don't know anything about using composite construction for a propeller. I
do know a little about fiberglass and carbon fiber composite, just from an
"educated layman" point of view. So bearing that in mind, I would be
worried about:

1) Would continual flex/unflex cause fatigue and how would you detect it if
it's internal? (I think in the research environment they basically CAT scan
parts to look for internal fatigue?)
2) How could you tell a trivial rock ding from a potentially disastrous one
(again, hard to see what's inside)?

Again, I'm not all all claiming these things happen, I just am asking if
people know of any gotchas. Of course, there are lots of testimonials that
basically say "I've had mine for X years and it hasn't broken yet", but
that's not really data.

Secondly, does the electric system work automatically (so that you don't do
anything), or is there a control that works like manifold pressure (i.e.
"governed" so that changes in RPM cause automatic changes in blade pitch),
or is there just a blade pitch control? Why would it be better/worse than
hydraulic?

Does anyone out there have one who can ring in on this?