Harry Gaydon was the son of a wealthy Kingston-upon-Thames watchmaker and jeweller who, like his son, was a long-time member of the Royal Burnham Yacht Club. Graydon junior made an impression racing dinghies at Burnham in the early 1920s and, in Y Wurry, was the overall winner of the International Cup at the Burnham International Dingy Week in 1921. He was second the following year but won it again in 1923 and 1924, latterly with the dinghy Iwunda. Gaydon was elected onto the committee of the Yacht Racing Association in 1927 and the following year competed at the Amsterdam Olympics where he finished eighth in the one person dingy class. Gaydon continued racing into his fifties, and at the age of 58 enjoyed successes in the Dragon Class with Andromeda.
Great Britain