I was examining the plans again today, and I noticed it calls for 1/8" ply for all of the fuse formers. Wondering if that isn't a bit overkill, and 1/16" would work just as well and cut some weight too. And in regards to the thrust tube, the plan has the fan unit right at the back of the fuse, so to append a 3-4" thrust tube it seems you would have to fabricate a support for it dropping down from the tail boom. Actually, it looks like there would be enough room in the fuse forward the fan that you might could move the fan forward and keep the thrust tube internal. But who am I to think about re-engineering a Ziroli plan. Besides, I've seen it fly and it seems fast enough for my old eyeballs and reflexes. What I don't recall seeing on the plan is the small central fin on the lower front of the fuse that Nick used to bungee launch the plane. CC