Just think of the fun flying and be able to do about any type of slow or fast maneuvers with a 20cc DLE and usea plane like the ones show in photos below.A bigger 30ccc engine could be put on a profile like the complete home-made airplane show. Or just use any bigger profile with the same (inverted) engine install. Any way you do it...it should be cheap to run & fun to fly! Capt,n