Supermarine Napier S.5 monoplane, late 1920s

"The Supermarine S.5 was a 1920s British single-engined single-seat racing seaplane built by Supermarine. Designed specifically for the Schneider Trophy competition, the S.5 was the progenitor of a line of racing aircraft that ultimately led to the Supermarine Spitfire."

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