The H.S.T.10 was a low-wing cantilever monoplane powered by two Napier Rapier VI engines. It had a retractable conventional landing gear with an enclosed cabin for two pilots and twelve passengers. It was fitted with a single-spar all-metal wing, known as the Duncanson wing, that had previously been tested on a Blackburn Segrave. The prototype used test serialB-9. In 1937, the project was abandoned, and B-9 was given to Loughborough College as an instructional airframe.