40+ years ago I waved the baton for a winch launch, a dual instruction flight in a T31b, while wondering if an instructor, taking a photograph, was in a safe place. As he was an instructor, I assumed he was O.K.
The wing hit him on the forehead, (fortunately between wing ribs)
He survived, with no permanant damage, but it was several days later before he was fully aware of what was going on.