The snow patrol drones saving skiiers from an icy death

Being buried alive is a scenario most of us thankfully only experience in nightmares. But for off-piste skiing fans, lured by the thrill of carving their own tracks through fresh powder snow, it's an ever-present risk. More than 150 people - mostly skiers, snowboarders and snowmobilers - are killed in avalanches every year, according to National Geographic statistics. This month alone, there have been deaths in Switzerland, Italy, Canada and North America. Drone manufacturers claim UAVs (unmanned aerial vehicles) could slash the toll by finding victims faster, and allowing ski patrollers to clear snow on high-risk slopes using explosives - without endangering themselves.