I'm still trying to figure out how he got pinned under a tree as he cut it. I have felled a few trees in my time, starting with 12" or so pines when I was too small to swing an axe, I cut 'em down with an old rig axe (or half hatchet as some call them). I can see getting smacked in the face with the butt of the tree as it kicks back, but not pinned under. Maybe the thing was down and he was limbing it. It could then roll and get you, if you were silly enough to be on the downhill side...