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Fall on Rock, Top-Rope Anchor Pulled Out, Wyoming, Blacktail Butte

FALL ON ROCK, TOP-ROPE ANCHOR PULLED OUT

Wyoming, Blacktail Butte

On July 5, 1986, Chuck Blackwell (27) was attempting a 5.11 move on Blacktail Butte when he fell about a meter. His partner, Chris Lloyd (24), was belaying from below—the rope being anchored on top. The anchor came away, and Blackwell, the rope, and anchor rigging fell nine to 12 meters onto a narrow rock ledge. He continued to tumble the rest of the way down into a tree and bushes. He was evacuated to St. John’s Hospital, where his injuries were reported as fractures of the pelvis, ankle, and ribs, and a pneumothorax. (Source: Joel Ellis, Ranger, Grand Teton National Park)

Analysis

I investigated the top-rope anchor that failed on July 5, 1986, at Blacktail Butte that resulted in the injury of Chuck Blackwell. The anchor was set up by Chris Lloyd, who had climbed at the same place four days previously. At that time, Lloyd’s climbing partner (not Blackwell) set the anchor. Lloyd remembered that the anchor took small nuts, so that was all that he took to set up the anchor.

One of the anchors was a #8 Stopper slung with nylon rope set into the crack between the wall and a detached rock. After the accident, it appeared that the rock had not moved, since the soil at its edge was not disturbed. A 2.5 meter length of 2.5 millimeter nylon webbing was attached to the nut sling by a carabiner. About two meters from the carabiner, a loop was tied in the sling, and a carabiner for the belay rope was attached. The end of the webbing was tied to another piece of webbing that was clipped to twosmall Stoppers that were placed side by side in a horizontal crack about two meters from the #8 Stopper. It was difficult for me to get a good placement for the two small nuts in the horizontal crack. Right next to this placement was a good placement for a #2 Friend, but Lloyd didn’t bring anything that big.

When Blackwell fell, this anchor failed and fell to the ground attached to the belay rope. In reconstructing this anchor, the only way I could get it to fail was to assume that the #8 Stopper loosened and slid deeper into the crack. If it did this, it easily slipped through the crack and fell out the bottom. If this happened, the load would be put on the two small Stoppers. I was able to place them so they seemed secure; but they pulled out when jerked hard.

This accident points out that nuts do wiggle loose unless they are set, or better yet, backed up by other pieces. (Source: Dan Burgette, Ranger, Grand Teton National Park)