Sorry to hear about your friend. We had a similar accident this weekend. Our 3rd rider in line went around a corner and hit a 6" maple tree with his body leaning off of the machine. Broke 4 ribs, punctured 1 lung, separated and torn shoulder, broken collarbone and a severely bruised left knee. No alcohol was involved. He rode the sled for another 5 miles before we called the ambulance and hauled him to ER. There were 4 other people in the ER from snowmobile crashes that night alone. Not a good way to end a ride..