JASON Walker of Uffculme, together with friends Mervyn and Susie Rice from Bratton Clovelly, are taking part in a triathlon challenge, in order to raise funds for the Devon Air Ambulance Trust.  The team event involves a 1500m open water swim, followed by a 40km (25 mile) cycle and finally a 10 km (6 mile) run, with each team member undertaking one discipline.  Susie said: 'I wanted to take part in some kind of challenge in 2008, in order to celebrate reaching 50, and came up with the team triathlon event with my husband Mervyn.  'We were short of a cyclist and knowing that our friend Jason was a keen cyclist in his youth, asked if he would be interested in joining in.' Susie said they chose to support the air ambulance after the service rescued a friend after a riding accident on Dartmoor. The remaining triathlon dates are July 20 at the Mountbatten Centre in Plymouth and August 9 at the Excel Centre in the Docklands, London.  To support or sponsor the triathlon challenge contact Mervyn or Susie on 01837 871216.