The first thing most people damage are the props. Always good to have a few spares if you can.
Then once you hit a tree, the Phantom usually falls to the ground.
if that ground is hard, and it hits at the wrong angle, the next thing to break is the shell... right by the skinniest part of the arm, you'd get a buckling and the arm would be bent. some people manage to fix it a bit by applying heat. but it usually requires a new shell, which isa bout $50 or so, and takes a few hours to swap out everything.