I built a ME-163 that has a 82 inch span. I built the plug, mold and the fuse out of fiberglass. I also built the take off dolly, works good. I also built a 50 inch version out of glass. The small one screamed with a front rotor rear exhaust OS40. The big one moves along great with a Jett 90 rear exhaust. On both the tuned pipes are enclosed in the fuse. There was a picture of the big one in a old "Flying Models". Mike Krizan [email protected]