This has nothing to do with rotary engines but for all
you RC model fans out there this pictures was taken
about 1952. I found an old collection of negatives
and had them scanned.

It was a field meeting of the District of Columbia RC club of which I
was a 17 year old teenage member. The guy in the pith helmet with his
back to us is Dr. Walter Good the inventor of the radio controlled
airplane pre WW II. The girl facing the camera is
my sister Louise. To the right of her the dorky kid
looking on is me. I am standing in front of my Nash Rambler
convertible. The receivers were one or two tube super regen. Usually
rudder only control.
-----------------------------

After all that build up then I forgot to attach the damn pic.
Sheesss.

Paul Lamar ...No rotor no motor.

WOW Paul !!! That is fantastic !! Would you believe your sister's smile
was the first thing I noticed ??  It is a striking photo of her. She was
quite the looker then :-))  They planes were of course the second thing
I noticed..  Single channel rudder only ? Was it analog proportional
control ?
-dave

In some case it was pulse width modulation as I recall. The hot
ticket in those days. 50/50 stright ahead. 60/40 one
way or the other. If you slowed the modulation rate the air plane
would wag its tail as it flew around. No end of entertainment
when that happened :) we were just talking about proportional
control in those days. Very advanced and on the distant horizon.