This guys name is Daren Rahlves.  By skiing down this slope he starts an avalanche.  This video is shot in Alaska .  Because he has an airbag, it saves his life.  An avalanche is a mass of snow, ice and rocks falling rapidly down a mountainside.  As it gets near the bottom, its gains speed and power. This moving snow can go more than 80 mph. Avalanches kill more than 150 people in a year so the airbag really did save this guys life.