The S-30 design for a light transport and mail aircraft was not built. The five-seat S-31, with a 200hp Wright J-4 Whirlwind engine, was used by the Fairchild Company for aerial photo-mapping work in South America. Up to four passengers, or photographic equipment, could be carried in the semi-closed centre cabin. During flight testing, the S-31 climbed to 4680m in 47 minutes with a pilot, two passengers and fuel for four hours of flying.