No. 5 Group RAF effective squadrons of Bomber Command, personified by No 617 Squadron the "Dambusters", formed from 5 Group aircrew in March 1943. Most of the group's main airfields were around Lincoln, including RAF Scampton. By the end of the war the group had grown to 15 squadrons. The group was noted for its high accuracy bombing, being involved the sinking of the "Tirpitz" in November 1944 and the shattering of the strategic Bielefeld railway viaduct in March 1945. The Group introduced new weapons operationally, including Barnes Wallis's "bouncing" and his Tallboy and Grand Slam "earthquake" bombs. The group was disbanded on 15
No. 617 Squadron RAF Vulcan force was held in reserve for nuclear strike duties only. The squadron's Vulcan B2s served mainly in that low-level penetration role until disbandment on 31 December 1981.The Squadron reformed on 1 January 1983 at RAF Marham, re-equipped with twelve Tornado GR1 aircraft and eighteen WE.177 nuclear bombs, and the Squadron's role assigned to SACEUR remained one of support for land forces on the Continent. Its Tornado aircraft were each able to carry two WE.177 bombs and the ratio of weapons to aircraft at full strength increased to 1.5:1, with an allowance now made for attrition in the conventional opening