The Short Stirling was a British four-engined heavy bomber of the Second World War. It has the distinction of being the first four-engined bomber to be introduced into service with the Royal Air Force (RAF) during the war (the earlier Handley Page V/1500 being a WWI design that served during the 1920s).
The Stirling was designed during the late 1930s by Short Brothers to conform with the requirements laid out in Air Ministry Specification B.12/36. Prior to this, the RAF had been primarily interested in developing increasingly capable twin-engined bombers, but had been persuaded to investigate a prospective four-engined bomber as a result of promising foreign developments in the field. Out of the submissions made to the specification, Supermarine proposed the Type 317, which was viewed as the favourite, whereas Short's submission, named the S.29, was selected as an alternative. When the preferred Type 317 had to be abandoned, the S.29, which later received the name Stirling, proceeded to production.