RAPPEL FAILURE/ERROR–NO BACK-UP BELAY AND NO KNOTS ON ENDS OF ROPES
Wyoming, Devils Tower National Monument
On May 17, Jacqueline Weimer (27) sustained fatal injuries after falling approximately 100 meters while rappelling adjacent to the popular El Cracko Diablo climbing route on Devils Tower.
Weimer and her climbing partner had just completed the Soler (5.9) and rejoined three friends in the Meadows, a large ledge system high on the south face of Devils Tower. The group of five decided to rappel together and rigged a double-rope rappel through fixed anchors using 60 meter ropes. A newer, smaller-diameter rope was threaded through the anchors and tied to an older, larger-diameter rope using a Flemish bend. The first person to rappel descended 59 meters—past two sets of intermediate anchors—to a narrow ledge with anchors. Using a different rope, he rigged a single-rope rappel at these anchors and continued down the remaining ten meters to a large ledge. The group planned to descend singly down the double-rope rappel, switching rappels at the small ledge, and then continue down the single-rope rappel, ultimately regrouping at the large ledge. (Although still high-up, this ledge forms the base of Soler and other routes and it is accessed by third class terrain from below.)
While waiting turns to descend the double-rope rappel, each climber observed that the joining knot traveled slightly away from the anchors. Each readjusted the knot before descending. Weimer was the fifth and last person to rappel. At this time her partners were changing shoes and eating lunch at the large ledge below. Weimer reached the intermediate rappel anchors. However, instead of immediately clipping in, she remained in a rappel stance on the two ropes. She then leaned briefly to her right in order to look up and consider how the ropes would pull. At this point her partners watched her fall backward, hit the large ledge, tumble, and continue to fall out of sight. Weimer was found with approximately three meters of excess rope—of the thicker, older rope—running through her rappel device. Presumably, she lost control of the other rope and it slipped through her rappel device.
Several factors contributed to this accident, including the extreme length of the rappel, the absence of blocking knots tied at free rope ends, and uneven rope lengths on the double-rope rappel. The compound effect of these factors resulted in a tragic accident.
Choosing to skip two sets of intermediate anchors forced the climbers to rappel dangerously close to the ends of their ropes. Only one to two meters of excess rope are generally available when this same narrow ledge is reached on a double-rope rappel using two standard 60 meter ropes. Nevertheless, many climbers prefer to avoid the hanging stances found at the intermediate sets of anchors and choose to rappel to this same narrow ledge. Although recognizing the length of the rappel, Weimer and her partners still made the conscious decision not to tie blocking knots at the free ends of their ropes because they were concerned that these knots might hang up when the ropes were tossed. Tying, or tossing and then retying, blocking knots can effectively eliminate the risk of rappelling off of rope-ends.
The group intentionally threaded a newer, smaller-diameter (10.2 mm) rope through the anchors and then tied in an older, larger-diameter (10.5 mm) rope, because they felt that doing so would allow for easier rope retrieval. However, this rigging allows the joining knot to travel through— instead of jamming against—the anchors if, on a double-rope rappel, the thinner rope passes through a rappel device slightly faster than the thicker rope. Indeed, while waiting turns to descend the double-rope rappel, each climber observed the joining knot traveling (about 1/2 meter) away from the anchors. Thinner, less worn ropes tend to travel through rappel devices slightly faster than thicker, more worn ropes because slightly less friction is applied to them by the rappel device. This effect can be eliminated if the rappel is rigged in reverse. Larger diameter (or more worn) ropes should be threaded through the anchors and then tied to smaller diameter (or less worn) ropes. In this scenario, instead of traveling, the joining knot will simply jam against the anchor, thereby maintaining even rope lengths.
It is significant that the rope diameters involved in this accident were fairly similar (10.2 vs. 10.5 mm). In this instance it is possible that the differences in sheath wear between the older rope and the brand new rope exaggerated the slight difference in diameter between the two ropes. It is unclear whether the JAWS descending device used by Weimer further exaggerated the situation because of the greater stopping power/friction that this device provides in comparison to other rappel devices. (Source: Chuck Lindsay, Climbing Ranger)
(Editor's Note: Things have changed since 1959, when my partners Carl and Jean Love and I were the 68th-10th to ascend the tower by the only known route. Now there are 6,000-8,000 climbers a year attempting one of the 220 named routes. On this day, there were 82 people on the various routes. Considering that more than 80,000 climbers have visited the monument, the accident rate is low and there have been very few fatalities, most of them, due to rappel errors.)