SIG SU-31 structural failure
I have one with a BME 50cc engine. The plane wieghs 16.0 lbs complete. Use good servos and hardware. Make sure the ailerons and elevator fit well with no gaps before you epoxy them in place. I found much of the assembly time for me was getting all the hinges to fit well.
I heard many second hand horror stories about the wing but it seams very strong to me. There are only a few first hand reports of wing failures.
It does take 2-2.5 dgrees of right thrust and its not built in and it takes 20 degrees of up elevator mixed in to get a good knife edge.
But it does real well in the pattern work and looks real nice.
I get lots of compliments about it out at the field.
Joe Brannon