Max has been using herself as a weapon against Thomas lately. He'll just be minding his own business, and she'll suddenly fly into him at full speed. Last night, she hit into his head so hard he was worried she may have injured herself.
This was not the case, as she did it again this morning. He said it was kind of a blur, but he remembers her feet heading toward him "like a raptor!" Then the collision; finally, pain on the side of his head. When he looked up, Max was on her stand, preening herself as if nothing had happened.
Max is a very good flyer, so this is clearly intentional. I suspect it's hormonally-driven. He's promised to be more alert so he can duck.