Saw that happen once. A one ton truck with a flat deck was coming towards me on the highway. 'Something seems odd' I said to myself, eating my chips, 'his outside dual tire is on an angle'. It was attached and everything, but somehow was turning at an angle to the truck.
My brain obviously wasn't turning over too quickly, cause I didn't grasp what was going on. But sure enough, I checked in my rear view mirror as he went by and the outside tire (which must have been only hanging on by a couple studs) came off the truck right after he passed me and went flying across my lane to the opposite ditch. Followed shortly by the inside dual, whereupon the truck's axle fell to the highway in a big shower of sparks.
Kinda wonder what would have happened if that tire would have came off in front of me. Sometimes stuff seems so unreal it's hard to react to it. 1) 'That's odd' 2) tire comes through windshield 3) die