Glacier ski touring crevasse rescue is a fundamental skill when ski and splitboard touring on a snow covered glacier, an un-roped crevasse fall results in potentially the most challenging technical rescue situation that is likely to be encountered in the mountains.
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Glacier Ski Touring Crevasse Rescue
Building an Anchor
The first stage in responding to an un-roped crevasse fall, the team members on the surface will have first build an anchor so that they can safely approach the edge of the crevasse to assess the situation. During the winter and spring seasons, ski and splitboard tourers are likely to encounter soft snow on the surface of the glacier. In mid winter and immediately after fresh snowfall it may be dry snow. Later in the spring season, particularly after rain or a number of melt-freeze cycles , the snow will likely be wet.
In soft snow, the strongest possible anchors are created by placing an object with the biggest surface area as possible, as deep as possible and pulling from the middle. In this context, it is likely to be skis. Two skis should be placed with bases facing each other or using skins or some other padding to protect the sling from getting damaged on the edges if using one ski and with a sling hitched around the midpoint of the ski for an attachment. Other options include burying backpacks, stuff sacks filled with snow.
Preparing the lip
Whenever approaching the edge, the rescuer should be attached to the anchor and protected from falling into the crevasse. Attach the end of the rope to the anchor, place a prusik around the anchor rope, extend it if required using a personal anchor system, and keep it tight as the edge is approached. Once at the edge, the rescuer will be able to re-establish communication with their partner and assess the situation.
If the victim is not injured, the rescuer should be able to drop an end of rope down so that they can climb out on belay or self-rescue by prusiking up the rope. If the victim is incapacitated to the extent that they can’t clip themselves onto the rescue rope, the rescuer will have to first abseil down, attach the victim, and then climb or prusik back.
If the victim is unable to climb out themselves, the rescuer will have to construct a hauling system on the surface. It is first worthwhile preparing the lip by removing any soft snow, building a step and providing support under the rescue rope so it doesn’t dig into the soft snow surface. Whatever you use for this, an ice axe or backpack, make sure it is secured so it can’t be dislodged and fall into the crevasse.
2:1 Assisted Haul
The simplest hauling system, if the victim is able to help, is a direct 2:1 haul with a Microtraxion® or similar progress capture device on the victim. The victim can assist by pulling on the rope moving towards them. The rescuer can stand protected on the edge and pull directly up on the rescue rope. Although there is not much mechanical advantage, friction is minimised as there are no moving ropes running over the edge, and the inefficiency of rope stretch is minimised.
With more than one rescuer or without a Microtraxion® available, a simple progress capture prusik can be placed on the rescue rope and allows for multiple rescuers to pull on the rescue rope away from the edge.
3:1 – Z Pulley
If the victim is unable to help or there are a number of able rescuers on the surface, the 3:1 ‘Z-Pulley’ is the next solution. If limited rescue rope is available, this is an efficient use of rope. There is only one strand of loaded rope moving over the edge and rescuers can pull away from the edge using strong legs.
With all hauling systems, it pays to minimise friction by making sure efficient equipment is used as much as possible and ensuring that snow is dug out from under moving parts of the system.
Compound pulley systems
For a simple pulley system, increasing the theoretical mechanical advantage beyond 4 or 5:1 tends not to increase the practical advantage due to increasing friction and inefficiencies of the equipment. If simple systems are not working, then a bigger mechanical advantage can be achieved by combining two simple systems into a compound system.
For more information and to sign up for expert instruction from certified mountain and ski guides, check out Wānaka Mountain Guides’: short local Glacier Travel and Crevasse Rescue Courses or multi-day, high alpine-based Glacier Ski and Splitboard Touring Courses or Ski Mountaineering Courses.