 Fairchild designed the aircraft in response to a Pan American Airways request for a small flying boat to operate on their river routes along the Amazon and Yangtze.The result was a conventional high-wing cantilever monoplane with its radial engine mounted above the wing in a streamlined nacelle.Before construction of the prototype was complete, however, Pan American no longer required the aircraft to operate in China, and Fairchild modified the design to optimise it for the tropical conditions of Brazil.