American Alpine Jounrna and Accidents in North American Climbing

California, Yosemite Valley

  • Accident Reports
  • Accident Year:
  • Publication Year: 1974

California, Yosemite Valley. On October 17th David Bryan (age 20) and Michael Harrison (24) were attempting a new route on the Glacier Point Apron. Harrison Jumared to the top of a rope he had fixed previously. The rope was attached by one carabiner and an overhand knot to a belay bolt. The bolt was a one- inch Rawl drive expansion type. The hanger was homemade of aluminum angle stock. It had been placed by Harrison the day before. The rope did not run vertically down the face from this belay bolt; ten feet to the left and slightly lower it ran through a carabiner attached to another bolt. As Bryan followed Harrison he reached the lower bolt and unclipped the rope from it. His weight, in addition to Harrison’s, came onto the belay bolt. It failed and both men fell to their deaths. (Sources: Mark Forbes, Mead Hargis.)

Analysis: The exact cause of the failure is not known. The hanger remained attached to the rope. The bolt itself stayed in place and (viewed through field glasses from 100 feet away) appears to have stripped threads and be bent slightly downward. Harrison’s homemade hangers were thicker than commercial hangers. Thus one explanation would be that the nut was not screwed all the way down, so that when the weight of the two climbers came onto the bolt the few threads actually holding the hanger stripped off. Harrison was, however, experienced at bolt placement and ought to have seen this weakness. Another explanation is that rope motion rotated the hanger slightly and gradually unscrewed the nut — Harrison might have been leaning to the right of the bolt, and the rope to Bryan ran to the left and down. Bolt failure is rare, but a completely safe belay system would have two independent anchors. (Sources: Forbes, Hargis.)

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