"Peter Dohm" wrote

As far as the rotaries go, you seem to have missed that whole sequence by
at least ten years.

Other than the obvious poor fuel efficiency, which was probably no worse
than two-cycle engines, I really can't comment--because I never saw an
installation (or plans for one) with properly designed cooling.

There has been one at OSH for all of the 4 or 5 times I was there, that
seemed to get along quite well. Tracy Crook -
http://www.rotaryaviation.com/
--
Jim in NC