Can You Slide Down a Mountain on Purpose? Yes, and It Kills People
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Sliding down a snow slope under control is a fast and legitimate way to descend, taught alongside the technique for stopping. Most accidents happen because somebody skipped the second part.
What the technique is
The descent involves deliberately sliding down a snow slope, controlling speed and direction rather than simply falling, and it is a standard part of mountaineering technique rather than an improvisation. Three forms are used. Sitting gives the most control and the most contact with the snow and soaks the climber through. Crouching keeps the boots on the snow with the body balanced above, which is faster and harder. Standing is effectively skiing on boots and demands real skill. In all three the ice axe is held ready and dragged as a brake, which is the part that makes it a technique rather than a slide.
When it is appropriate
The conditions have to be right and checking them is the whole decision:
- •Snow soft enough to slow a slide, not hard ice
- •A slope of moderate angle that eases off rather than steepening
- •A clear runout, visible to the bottom, with no rocks or drop
- •No crevasses below, which rules it out on most glaciers
- •Crampons removed, since a point catching will break a leg
- •An ice axe in hand and the ability to use it
Why crampons are the danger
The single most consistent cause of serious injury is descending this way with crampons still fitted, and the mechanism is grimly simple. A sliding boot with steel points on it catches the snow abruptly, the boot stops and the body does not, and the resulting force goes through the ankle and the knee, producing fractures and dislocations at speed on ground where evacuation is difficult. Accident reports from mountain rescue services record this pattern year after year. The instruction to remove crampons before sliding is absolute in every textbook and is ignored because removing them takes time and because the slope looked easy.
The snow that decides it
Judging the snow is the skill that separates a safe descent from a fall, and the assessment is specific rather than general. Softening snow in the afternoon sun gives good braking and is ideal, and the same slope at dawn may be frozen hard and entirely unsuitable. A thin soft layer over hard ice is the worst case, since it looks and feels safe and offers nothing to the axe when the slide accelerates. Old avalanche debris is lumpy and stops a slide violently. Sun-warmed snow over a shaded slope changes character within a few metres. Kicking a heel in and testing the axe before committing is the standard check.
The stop that has to work
The technique is only as safe as the ability to arrest a slide that has become too fast, and that skill is practised separately and deliberately. Self-arrest involves rolling onto the front, driving the pick of the axe into the snow beside the shoulder, keeping the weight over it and lifting the feet clear of the surface, and it must be practised on a safe slope until it is automatic, because there is no time to think about it. It also has limits, since it works poorly on hard ice and not at all above a certain speed. Judging that a slope is suitable before starting is therefore more important than the recovery, because the recovery may not be available.
The takeaway
Sliding down snow in a sitting, crouching or standing position with the ice axe dragged as a brake is a legitimate descent technique, requiring soft snow, a moderate slope, a clear runout visible to the bottom and crampons removed. A crampon point catching stops the boot and not the body, which breaks legs and is the commonest serious injury. Self-arrest has to be automatic and still has limits.