Wyoming, Grand Teton National Park, Disappointment Peak—Eric Mendelsohn (20) and Neil H. Drake (19) had completed an ascent of Disappointment Peak and were in the process of descending to Amphitheater Lake when Mendelsohn stepped onto a snowfield where his feet slipped out from under him and he slid about 15 feet into the rock beside the snowfield, hitting the rocks feet-first and then rolling an additional 15 feet through them. In his travel through the rocks he hit his head causing extensive injury around the mouth and head and bruises over the entire body.

Source: Frank R. Oberhansley, superintendent and Doug McLaren, Park Ranger, G.T.N.P.

Analysis: The party was not equipped for snow and they also apparently had not had adequate experience in snow work.