Previously I wrote:

George's static RPM:  5000
George's RPM at rotation:  5100
Perry's static RPM:  4800
Perry's RPM at rotation:  5000

In the interest of accuracy just wanted to let you know there is an
error here.  I just got clarification from George, his RPM at rotation
is 4100.  It's interesting the prop has such a wide operating range,
4100 - 6000+ engine RPM.  My fan is 4800 - 5300 with no droops in the
speed range.

--
Perry J. Mick
Mick Duckt N7XR
http://www.ductedfan.com

I think he has way less power than you do Perry. I am sure your stock
Mazda tuned intake EFI system is way better than his log manifold with a two
barrel carb. I think your fan tips are up against the mach # brick wall.

I calculate a vector sum of 909 fps with 5300 rpm and 160 knots in the
fan.
Doesn't seem like the brick wall should start that early.  Maybe it
does.
Isn't mach one around 1100 fps?

--
Perry J. Mick
Mick Duckt N7XR
http://www.ductedfan.com

Depends on a lot of things such as temp and air density not the 
least of which is the airfoil used. What are your tip airfoils
now a days? 

I know you know that but for others that might not.
BTW 600 MPH is 880 fps. 700 MPH is 1027 fps. You are up there.

Paul Lamar
 
The Aircraft Rotary Engine Newsletter.              Powered by Linux.

http://home.earthlink.net/~rotaryeng/            http://www.linux.org