V bombers

The term "V bomber" was used for the Royal Air Force (RAF) aircraft during the 1950s and 1960s that composed the United Kingdom's strategic nuclear strike force known officially as the V force or Bomber Command Main Force. The three strategic bombers, whose names all started with the letter "V", and so were known collectively as the V class, were the Vickers Valiant, which first flew 1951, and entered service 1955; the Avro Vulcan, which first flew 1952 and entered service in service 1956; and the Handley Page Victor, which first flew in 1952 and entered in service 1958. The V Bomber force reached its peak in June 1964, with 50 Valiants, 70 Vulcans and 39 Victors in service.

When it became clear that Soviet Union's surface-to-air missiles like the S-75 Dvina could successfully bring down high flying aircraft, the V bomber force changed to low-level attack methods. Additionally, standoff weapons were introduced, starting with the Blue Steel missile. It was then planned to move to the much longer-ranged Skybolt air-launched ballistic missile. When the US cancelled Skybolt the survivability of the V force was highly questionable. This led to the Royal Navy taking over the nuclear deterrent role in the 1970s, using UGM-27 Polaris intercontinental ballistic missiles launched from nuclear submarines. The tactical role passed to smaller aircraft like the SEPECAT Jaguar and Panavia Tornado.

...
Wikipedia