saw this pic in an article about NSM model engines.

makes you want to say hhhmmmmmmmmmmm.................

Carl

Brett

call it a senior moment  LOL

Carl

  A glow plug will really screw into the thread in the crankcase.

    Brett

  And the prop is spinning with the help of compressed air, I'm reckoning.. Back in the days of American Aircraft Modeler, there was an article on the "Zero Stroke Engine"  that was really quite well written. And in Model builder one year, there was an article of 'Helispheres", microballoons that were filled with helium to actually make your model lighter after application! It was very well written also.
  Type at you later,
   Dan McEntee

I believe that is, indeed, a zero stroke engine.  It's too bad that the powers that be refused to make a competition class for them.

They are legal in 1/2A.