America's Cup bosses have promised a full investigation into the accident in which British Olympic gold medal winner Andrew Simpson died. Simpson (36) was sailing with the Swedish Artemis team in San Francisco Bay when his catamaran capsized today, trapping him underneath.

The sailor, a gold medallist at the 2008 Olympics affectionately known as “Bart”, was one of 11 crew members aboard the 72ft vessel which flipped over at about 12.30pm local time.

He was trapped underwater by the AC72 catamaran’s platform for about 10 minutes, his team said, and doctors both in the water and on the shore could not revive him after he was freed from the wreckage.