Supermarine S.6B

In the 1920s mihI early 1930s seaplane racers were the fastest aircraft on the planet. Built purely for speed, entrants for the biennial Schneider Trophy contest were at the cutting edge of progress in streamlining, high-performance engines, and high-octane fuels, Britain won the trophy in 1927 and 1929 with sleek Supermarine monoplanes designed by Reginald Mitchell. For the 1931 contest, Supermarine adapted their 1929 winning design, the S.6.
Two S.6Bs were built, with a new version of the Rolls-Royce “R” racing engine and a better cooling system, A special fuel “cocktail” was created to wring the utmost power from the engine. The contest itself was a walkover, as Britain’s competitors, France and Italy, both withdrew before the event. But the S.6Bs still showed their mettle.
On 13 September 1931 Flight Lieutenant John Boothman made a fly-over of the sevenlap course averaging 340.08mph to claim the trophy, while in the second S.6B Flight Lieutenant G.H. Stainforth set a new absolute world speed record of 379.05mph. In another flight two weeks later the S.6B became the first aircraft to break the 400mph barrier, reaching 407mph. Britain was given the
Schneider Trophy for perpetuity, having won the contest on three consecutive occasions.
Supermarine and Mitchell went on to create the famous Spitfire fighter.