The Physics of Getting Stuck
Photo credit: Chris Burandt
Trees
When riding in the backcountry, there are a lot of trees and a lot of hills. When these two things mix the riding becomes extremely fun, yet very technical. When a rider is trying to make it up a steep hill using the side hilling technique, he is fighting gravity to keep his sled from getting pulled downhill. When the snow is deep enough, it is relatively simple because he can give it enough throttle to remain in the snow instead of on the snow. However, when trees are thrown in the mix, it becomes much more challenging. The thick branches of most trees protect the base of the tree from seeing any snow. This means that there can be three or four feet of snow on the hill, but around the base of each tree there is no snow at all. This creates essentially a sink hole. When the rider nears a tree, the snow around it is disturbed, and caves in to fill the empty area by the base of the tree. This can essentially be described as a very small avalanche. A rider can easily be sucked into the hole around the tree, as seen in the photo on the left. When this happens, it becomes incredibly difficult to get your sled out.
When riding in the backcountry, there are a lot of trees and a lot of hills. When these two things mix the riding becomes extremely fun, yet very technical. When a rider is trying to make it up a steep hill using the side hilling technique, he is fighting gravity to keep his sled from getting pulled downhill. When the snow is deep enough, it is relatively simple because he can give it enough throttle to remain in the snow instead of on the snow. However, when trees are thrown in the mix, it becomes much more challenging. The thick branches of most trees protect the base of the tree from seeing any snow. This means that there can be three or four feet of snow on the hill, but around the base of each tree there is no snow at all. This creates essentially a sink hole. When the rider nears a tree, the snow around it is disturbed, and caves in to fill the empty area by the base of the tree. This can essentially be described as a very small avalanche. A rider can easily be sucked into the hole around the tree, as seen in the photo on the left. When this happens, it becomes incredibly difficult to get your sled out.
Photo credit: SnoDrifters.ca
Getting Out
Getting stuck in deep powder can be extremely frustrating. The added weight of the wet snow on your sled, combined with the friction from all sides makes it nearly impossible to get out. The best way to remove a sled when in a situation such as the one shown on the right, is to get a riding buddy to give you a "ski pull." The loops on the tip of each ski are designed specifically for this reason. When a force is applied on the ski in the direction of the red arrow, it is pulling the sled forward and up at the same time. This is shown by breaking down the applied force into its 'x' and 'y' components, as taught in "Physics for Scientists and Engineers," by Randall Knight. While the 'x' component of the force pulls the sled in the forward direction, the 'y' component is pulling the sled up, and on top of the snow. A common mistake made by beginner riders, is to push on the back of the snowmachine. This is nearly useless because the 'y' component of that force is pushing it down into the snow, rather than on top where the sled needs to be.
Getting stuck in deep powder can be extremely frustrating. The added weight of the wet snow on your sled, combined with the friction from all sides makes it nearly impossible to get out. The best way to remove a sled when in a situation such as the one shown on the right, is to get a riding buddy to give you a "ski pull." The loops on the tip of each ski are designed specifically for this reason. When a force is applied on the ski in the direction of the red arrow, it is pulling the sled forward and up at the same time. This is shown by breaking down the applied force into its 'x' and 'y' components, as taught in "Physics for Scientists and Engineers," by Randall Knight. While the 'x' component of the force pulls the sled in the forward direction, the 'y' component is pulling the sled up, and on top of the snow. A common mistake made by beginner riders, is to push on the back of the snowmachine. This is nearly useless because the 'y' component of that force is pushing it down into the snow, rather than on top where the sled needs to be.