Supermarine Sea Lion III

The Supermarine Sea Lion III was a British racing flying boat built by the Supermarine Aviation Works. Designed by Reginald Mitchell as a modification of the Sea Lion II, it was powered by a 550 horsepower Napier Lion engine, and Mitchell reduced drag by changing the hull, giving it two bay wings and a larger rudder area. He expected speeds above 160 miles per hour. It was entered for the 1923 Schneider Trophy contest at Cowes, where Supermarine test pilot Henry Biard flew it to third place at 151.16 miles per hour. The Sea Lion II had won the 1922 race at 145.7 miles per hour, the first post-First World War British success in an international competition, and the Sea Lion III was that aircraft re-engined and renamed. Its performance led Supermarine to design racing seaplanes rather than flying boats.