Crevasse Rescue
On Denali there is an everpresent danger of falling into a crevasse, so climbers should never travel unroped. When a climber falls into a crevasse, his/her partners must immediately move into self-arrest positions to prevent the climber from falling any deeper into the crevasse.
While the rescuer farthest from the fallen climber remains in self-arrest, the rescuer closer by immediately sets up an anchor on the rope. This is done by hammering a picket or deadman into the snow. (An ice axe won't work.) The rescuer then attaches a sling to the rope with a tension knot, and the sling is attached to the anchor via a locking carabiner.
The knot should then be slid down the rope toward the fallen climber so as to take up tension on the rope. Meanwhile, the end rescuer can ease the load off him-/herself. For safety reasons, a second backup anchor should be placed and attached to the carabiner on the end of the knot. When the rope is secured, the rescuers should assess the condition of the fallen climber. If the climber is uninjured, he/she can then begin to climb out of the crevasse under his/her own power, using jumar ascenders or tension knots.
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