Project E

Project E was a joint project between the United States and the United Kingdom during the Cold War to provide nuclear weapons to the Royal Air Force (RAF) prior to Britain's own nuclear weapons becoming available. It was expanded to provide similar arrangements for the British Army of the Rhine.

The British nuclear weapons project, High Explosive Research, successfully tested a nuclear weapon in Operation Hurricane in October 1952, but production was slow and Britain had only ten atomic bombs on hand in 1955 and fourteen in 1956. The United States was approached to supply weapons for the V-bomber fleet, the British strategic bombers, until sufficient British ones became available. An agreement was reached in 1957. Under Project E, US personnel had custody of the weapons, and performed all the tasks related to their storage, maintenance and readiness. The bombs were stored in Secure Storage Areas (SSAs) on the same bases as the bombers.

The first bombers equipped with Project E weapons were English Electric Canberra bombers based in Germany and the United Kingdom that were assigned to NATO. These were replaced by Vickers Valiant bombers in 1960 and 1961 as the long-range Avro Vulcan and Handley Page Victor assumed the strategic nuclear weapon delivery role. Project E weapons equipped V-bombers at three bases in the United Kingdom from 1958. Due to operational restrictions imposed by Project E, and the consequential loss of independence of half of the British nuclear deterrent, they were phased out in 1962 when sufficient British megaton weapons became available, but remained in use with the Valiants in the United Kingdom and RAF Germany until 1965.

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