Driving the piston engined, wheel driven Railton Special he broke the Land Speed Record at Bonneville on August 23 1939 at a speed of . Without this being beaten he raised the record to in 1947. The record was unbeaten until 1963 when it was narrowly surpassed by Craig Breedlove in the jet powered Spirit of America.
During World War II he served as a pilot in the Royal Air Force and between 1943 and 1945 in the Air Transport Auxiliary. He reached the rank of Group Captain.
He died attempting to improve the water speed record at Loch Ness in the jet speedboat Crusader at a speed in excess of . There is a memorial to him erected by the people of Glenurquhart. He is buried at Christ Church, Esher.
On 27 March 1953 he was awarded the Queen's Commendation for Brave Conduct - John Rhodes Cobb (deceased), Racing Motorist. For services in attempting to break the world's water speed record, and in research into high speed on water, in the course of which he lost his life.