RE: Viper 500 flight problem
This is where the fuselage breaks at the front edge of the V tail mount. This can happen sooner or later to many of us if you don't take steps to strengthen it as suggested. This was found new in box this way, I think it had a rough trip from China. It's an easy fix. Remove the covering, drip in some thin CA, glass it all around and re-cover.
If this happens in flight, most of us won't have to worry about repairing it. I think this is what happened to my Viper #1 several years ago. Despite the Viper's shortcomings, it's still a great deal if you take the great advice on RCU.