Scott there are two thing I did to mine. One I glassed the center of the wing after I joined it. Some of the early ARFs folded the wing in flight. It didn't add much weight and was good piece of mind. Two, the top of the firewall would flex down when I revved up the engine. (ST3250) So I drilled three holes through the firewall and into the bulkhead with a 1/4" bit. Then epoxied dowel rods in place. I also added a better block with blind nuts to hold down the hatch in the same area. The wood screw vibrated loose. It flew great until I stripped out the AILE servos and lost it. It will be rebuilt the winter.

David