American Flyer wrote:

Has anyone explored the possibility of using a prop with say
four blades (or possibly even more) of say 35" diameter with direct
drive at 6000RPM instead of a PSRU? I know very little about the
aerodynamics of props, but I assume that at least one problem is
the fact that more of the airflow would be blocked by the engine
cowling. I notice that ducted fans have far more blades, but of
course have to be ducted, making them impractical for a conventional airframe.

Harrison Young

You must be new to the list Harrison, I've been flying one for over 4
years and 425 hours.

--
Perry Mick

-American Flyer wrote:

Perry,

Yes, I am new to the group. I've had an interest in rotaries
for some time, and am trying to decide just what I want to do about it.

Your airplane looks interesting, but it uses a ducted fan.
I'm specifically curious about a more conventional prop optimized for
high RPM use. I want to have two rotaries making 400HP each,
probably on a more conventional airframe than the EZ.

I will spend some time on your website. It looks like you
have a lot of interesting info there. Thanks,

Harrison Young

I haven't had the guts to fly my plane "ductless" yet.  I know the
static/low speed thrust is terrible without the duct and I loose ground
cooling ability. Theoretically it would be faster in level flight
without the duct, but I'm not sure it would climb worth a darn. One of
these days when I run out of other things to do on the plane I may take
it out on the runway without the duct and see how it feels on a high
speed taxi test.

--
Perry Mick
Custom Composite Props
mick@bridgingworlds.com
http://www.ductedfan.com

 
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