If we're going to talk about floatplanes, here's an idea to add to
   the mix.

   Floatplanes need "Beta" props, that is, props that reverse pitch. Not
   only is this really useful when you need to back away from short or
   pier, but it is really the only braking you've got.

   Now, if you look at the rotary engine, how hard would it be to set it up
   to rotate the "wrong" way? Looks like you just need a second starter
   and another couple of plug holes in the right place to support opposite
   rotation.

   It's probably not practical (Beta props aren't all that expensive or
   complex), but an interesting idea anyhow . . .

   Keith

   Unlike a two cycle a rotary will not run in reverse.

   -- Paul Lamar ...No rotor no motor.

   Paul is correct of course in that a rotary can't change direction like a
   2 cycle. By changing manifolding you can change direction of rotation,
   but it is a major undertaking. Everett Hatch had several reverse
   rotation engines. Probably to get correct prop rotation with earlier
   planetaries. The engine then intakes through the "exhaust" port and
   vice-versa. Only practical with a P-port engine. On the Mazda the
   cooling
   would be messed up too. But it can be done,it's just not practical for
   any kind of quick change.
   Bill Jepson


This is probably obvious, but I don't think reversing the direction of
rotation would be a practical means of providing braking.  What would be
entailed is completely stopping the engine and restarting it in
reverse.  At least several seconds transitioning.  Is that what was
being pondered?  With beta, the power lever is adjusted from normal
forward thrust, though essentially flat pitch (which provides quite good
braking at reasonable forward speeds) to a some amount of "negative"
blade pitch.  The nice thing about this is that the braking/reversing
effect can be modulated smoothly and easily.

This is not to say that I'm not interested in backwards rotation rotary
engines.  I think for a twin tractor/pusher airplane having one of the
engines rotate opposite from the other would be worth considering.

I wonder if the best way to make one run backwards is to actually build
mirrored end housings - taking the power from the other side of the
rotors - making the front the back.


Regards,

Matt-



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