Donald Sherman wrote:

You haven't spent enough time considering the stress levels in the
eccentric shaft and reaction gears carrying 900 hp @ 7500 rpm.  And you're
dead wrong about the weight.  My guess is Jim's engine would be twice your
estimate.  A problem is the heavy iron content.  Rotors and end plates are
still made of ferrous metal.
Who will be making all these wankel engines for general aviation???  The
junk yard supply won't last forever.  DS

Did you look at the engine in the dyno room? It had alloy end housings.

Sheesss Don your powers of observation are waning. Maybe you need 
a glasses prescription update :-)

The bare two rotor with cast iron housings weighs just under 200 pounds.
I am being pessimistic when I add 100 pounds to that for the three rotor
(with cast iron center and end housings I might add). Of course that
does not include the weight of the turbocharger.

There is a guy out in Riverside Able Ibarra getting 730 HP out of
a two rotor and he has many drag racing runs on it. Nobody has ever
broken an eccentric shaft as they are made from forged 4340 and the
stresses
are way less than they are on a comparable piston engine crankshaft.
The four rotor engine that won Leman had the same diameter eccentric
shaft so the stresses in a 900 HP three rotor are less than that.

The gears are not a problem if you cruise it below 8500 RPM.
I have just about all the SAE papers and both version of Yamamoto's
books
on the Mazda rotary engine. 1969 and 1981 versions.

I somehow get the impression i am writing an article for you :-).

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

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