Terrific image! Thanks so much.
One thing we are taught in racing school is that your helmet is no good if it doesn't remain on your head. The way to ensure that it does is to fasten your chin strap.
It seems he did not fasten his chin strap.
Too bad. So sad. Good pix, though.
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Although it is possible to die from blunt force injury to the body even if the head is spared, the brain is by far the easiest organ to smash.