Supermarine Commercial Amphibian

The Supermarine Commercial Amphibian, first called simply the Supermarine Amphibian and later given the Air Ministry designation N147, was a passenger-carrying flying boat and the first aircraft designed by Reginald Mitchell. It was built at Supermarine's Woolston works in Southampton for the Air Ministry seaplane competition of September 1920 and was based on the Supermarine Channel. A single-engined biplane flying boat with a wooden hull, unequal wingspans and a 350 horsepower Rolls-Royce Eagle engine, it seated the pilot in an open cockpit behind two passengers. It finished second but was judged the best of the three entrants for design and reliability, so its prize of 4,000 pounds was doubled. It crashed in October 1920 and was damaged beyond repair, but its showing led Supermarine to be commissioned to build the Seal II.