Joshua Tree National Monument—On October 30, 1954, Phillip Martin (17) and a companion joined a scheduled Sierra Club climb at Joshua Tree National Monument. They did not participate with the climbers nor climb under supervision, but climbed near by on their own. After observing the other climbers, they climbed a difficult rock using pitons and then decided to rappel off the rock. The rappel was set up using as a sling a single strand of nylon cord, tensile strength approximately 400 pounds. Martin rappeled and the sling gave away in some fashion; whether it broke or became untied is not known since it could not be found. He fell about 50 feet in two pitches of 15 and 35 feet respectively and suffered a concussion and bruises although he landed on his back.
Source: George Harr, Sierra Club, present at scene of accident; James Bonner.
Analysis: Good judgment would have dictated the use of at least two strands, individually tied, possibly more, for the sling. The sling was tied with a fisherman’s knot but this was not followed by hitches to prevent untying. The single loop was fitted snugly (horizontally) about a horn which greatly increased the stresses in the sling.