In January 1947, the British Air Ministry issued Specification B.35/46 for an advanced jet bomber intended to carry nuclear weapons and to fly near the speed of sound at altitudes of . Three firms: A.V. Roe, Handley-Page and Vickers-Armstrongs submitted advanced designs intended to meet the stringent requirements. While Short Brothers submitted a design, by Geoffrey T. R. Hill, that was judged too ambitious, the Air Staff accepted another submission from the company for a separate requirement, B.14/46, as "insurance" in case the advanced B.35/46 effort ran into trouble. Aviation authors Bill Gunston and Peter Gilchrist described Specification B.14/46 as "calling for little more than a traditional aircraft fitted with jet engines" Short submitted a conservative design to meet B.14/46, which became the S.A.4 Sperrin. Two prototypes were completed, the first conducting its maiden flight in 1951, but the Sperrin was ultimately relegated to research and development purposes only.