How do snow groomers keep slopes ski-ready?

After snowboarders and skiers have packed up their kit and started to head home, it’s time for the staff of a snow sport resort to start their daily maintenance. One of the most important tasks is snow grooming; the smoothing of the pistes that is diligently carried out every night. To do this a tractor or truck is normally used to carry specialist towing equipment. They operate by moving, flattening or compacting the snow to improve the condition of the surface, removing accumulated snow piles and redistributing them to cover icy patches or areas that have started to become bare. They also play an important role in maintaining the slopes by keeping snow depth even in high- traffic areas, constructing courses and creating terrain for tougher trails.

The machine runs on two large tracks made from rubber and steel that disperse the weight of the vehicle evenly across the surface. Fitted to the rear is a power tiller that churns the snow before a heavy comb or smoother pulls across the surface. This tiller is responsible for leaving behind the distinctive striped patterns of a groomed slope.

When you see the pistes before hundreds of skiers and snowboarders have taken to the slopes, you will notice lots of thin, uniform lines in the snow. These have been left behind by a snow groomer after the small cogs inside the vehicle have broken up the surface. The combing of the slopes of resorts in this way ensures a safe surface for users every day of the skiing season

Creating pristine pistes

How do these vehicles pick up clumps, smooth out bumps and spit out smooth snow?

Illustration by Adrian Mann (Click to expand)

This article was originally published in How It Works issue 119, written by Charlie Evans 

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