.then why in the world put a 15CC's weight in the airplane?
Because I haven't seen a 10CC or 5 CC gasser? In my original post, I suggested that I am doing a special covering scheme and do not want to get a lot of exhaust oil on it. I would like the sound of an glow or gas engine over an electric.
I'm sure there are lots of ideas about directing the exhaust away from the plane, but there will still get to be some on it. I would like to keep it as clean as possible. Having said that, has anyone seen 5 or 10 cc gas engines?