How F1 tech could help Ben Ainslie win the America's Cup

BBC News goes on board a high-speed catamaran with Sir Ben Ainslie and his team as they practise for the next leg of the America's Cup - a sailing race Great Britain has never won.

Technology will be key to success, says Martin Whitmarsh, chief executive of Sir Ben's team, Land Rover BAR.

These boats, which have more in common with F1 cars and aeroplanes than traditional yachts, are capable of speeds above 50mph.

Video journalist: Matthew Wall