A walker survived an avalanche in the Cairngorms that mountain rescuers described as huge. The Cairngorm Ski Patrol, ranger service and avalanche dog responded to an incident at the head wall of Coire Cas. Initial reports were of someone that had gone through the cornice or had been avalanched. Rescuers were on scene within minutes and found large avalanche debris. After approximately 45 minutes of searching and probing the response was stood down as the missing person was reported safe and well. The 47 year-old walker went through a cornice triggering the avalanche. The man, whose two friends had in…