I put the 550 in last week, because of a boom strike. here is the damage. It was the result of a boom strike, because I had allowed the anti rotation pin to become loose. One of the main blades hit the boom, and when it bent, it bent in such a way that allowed the tail blades to strike the boom as well.

Total damage: Main blades broken, main shaft bent, one tail blade broken, tail shaft bent, tail boom and torque tube bent, tail struts broken, main gear stripped, main shaft bent. The front tail drive gears wear also stripped, and both pitch links were missing and never found.

It was up and flying again a few hours after the crash, and I flew it the next day. :)