| SA.4 Sperrin | |
|---|---|
 Short Sperrin Gyron test bed (lower port engine) at Farnborough September 1955 | |
| General information | |
| Type | Experimental aircraft |
| Manufacturer | Short Brothers and Harland, Belfast |
| Status | Retired from experimental service |
| Primary user | Royal Air Force (intended) |
| Number built | 2 |
| History | |
| First flight | First prototype: 10 August 1951 Second prototype: 12 August 1952 |
| Retired | First prototype: 1958 Second prototype: 1957 |
The Short SA.4 Sperrin (named after the Sperrin Mountains) was a British jet bomber design of the early 1950s, built by Short Brothers and Harland of Belfast. It first flew in 1951. From the onset, the design had been viewed as a fall-back option in case the more advanced strategic bomber aircraft, then in development to equip the Royal Air Force's nuclear-armed V bomber force, experienced delays; the Sperrin was not put into production because these swept-wing designs, such as the Vickers Valiant, were by then available.
As their usefulness as an interim bomber aircraft did not emerge, a pair of flying prototypes were instead used to gather research data on large jet aircraft and to support the development of other technologies, such as several models of jet engines. The two aircraft completed were retired in the late 1950s and scrapped sometime thereafter.