i've had two... and i have given up! i fixed both no less than 3 times each, and have reached the conclusion that if you are going to build a plane then they should at least be able to fly with out torquing so much they fall from the sky! you shoulda seen my extra! i built the thing straight as an arrow with epoxy so it would be strong, a nd i took off and the stupid thing was all twisted after about 30 secs in the air! god!