the Blue Peacock British Army’s Forgotten Weapon isitors to AWE’s Historical V Collection are often puzzled and intrigued by one of the first exhibits they see in the display devoted to Britain’s nuclear weapons. At first glance the robust drab-green cylinder standing more than two metres high and mounted on massive cart springs seems to have little in common with the sleek exhibits elsewhere in the Collection.

Closer examination, however, reveals it to be one of the most fascinating items on display. Until recently, its very existence was a closely guarded secret. Now, papers released to the Public Record Office allow the story to be told. Known as Blue Peacock, this massive object is, in fact, the prototype of the British Army’s ‘atomic demolition munitions’, a nuclear land mine which was conceived in the early days of David Hawkings kneeling in front of the Blue Peacock exhibit in the AWE Historical Collection. nuclear deterrence.

A War Office specification for an atomic weapons programme had been set up charge makes an atomic mine particularly land mine first surfaced late in 1954. under the codename of High Explosives suitable for use in demolitions. A skilfully Almost immediately, a series of Research. By mid 1955, the Army’s sited atomic mine would not only progress meetings was held at the Engineer in Chief was able to define destroy facilities and installations over Armament Research and Development the operational policy for a novel type a large area, but would deny occupation Establishment at Fort Halstead in Kent, of weapon: “The large scale destruction of the area to an enemy for an a site where, in 1947, Britain’s nuclear caused by the explosion of an atomic appreciable time due to contamination.”

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The policy paper went on to suggest commemorates the men who made it. mid-European winter. Keeping Blue that suitable targets might be irrigation Despite the secrecy surrounding the Peacock warm involved swathing it in and hydroelectric systems, industrial weapon, its size meant that some glass fibre pillows. plants, oil refineries, railway junctions testing had to be done in public places, and canals. The Engineer in Chief pressure testing of the ‘boiler’ being Assuming everything went to plan, the recognised that owing to the shortage carried out in a flooded gravel pit near instruction manual predicted a yield of of fissile material, the Army weapon Sevenoaks. The ‘cover story’ was that 10 kT, producing a crater 375 feet in would be developed from the bombs an insulated container was being diameter from a surface burst, or 640 currently in service. In 1955, that tested, and if a nuclear association was feet if buried 35 feet below the surface. meant the Army’s mine would have to suspected, that it was to house ‘an be based on the Blue Danube free-fall atomic power unit for troops in the By October 1957, the design of Blue bomb then in service with the RAF. field’. The test was of course related Peacock was nearly complete, but at only to the steel casing and no radioactive headquarters, reservations were now Blue Danube was itself based on the material was involved. being voiced. The weapon was too device successfully detonated in large and heavy, and lighter warheads Britain’s first nuclear test, Operation By July 1957, the Army Council had (such as Red Beard) were on the way; Hurricane, in 1952. It was a single-stage decided to acquire ten Blue Peacock the fallout hazard was unacceptable; atom bomb comprising a plutonium mines and to station them with the pre-positioning a nuclear weapon in an core surrounded by a sphere of high British Army of the Rhine in Germany. allied country was politically flawed explosive, with a number of detonators If a Soviet invasion seemed likely, the and the weapon could not be stored in spread evenly across its surface. For weapons would be transported to the peacetime near to where it would be safety reasons, the fissile core was built target area, where they could be needed in war. into a tube assembly and would have deployed either on the surface, buried, been inserted through the explosive or submerged in a river or lake. The writing was on the wall. In into the centre of the weapon before Detonation could be either by wire February 1958 the MoD Weapons the aircraft left the ground. from a command post up to three miles Policy Committee decided that work on away, or by an eight-day clockwork Blue Peacock should cease, but that the This system was to have been at the timer. Anti-handling devices included a two inert prototypes should be heart of Blue Peacock. With an all-up pressure hull and a simple tilt switch. retained. One is thought to have been weight of sixteen thousand pounds If the pressure were lost, for example if tested to destruction; the other, having (over 7 tonnes), it was a massive gunfire pierced the hull, or the weapon languished for many years at an RAF weapon, with the bulky warhead and was moved or filled with water, it station, now has pride of place in twin firing units accommodated in a would detonate in ten seconds. AWE’s Historical Collection, where it protective casing, or ‘boiler’ as the remains as striking testimony to the original drawings described it. Other The whole operational scenario part played by the British Army in the than supplying the specification and appeared somewhat theatrical: the development of our nuclear arsenal. requirements for the warhead, nuclear warhead had to be kept within Aldermaston had little involvement in a specific temperature range, but This article was written by David Hawkings, the design of the weapon: a plate environmental trials suggested it might a regular contributor to Discovery, who inside the door of the device proudly not have survived the rigours of a was the manager of AWE’s Historical Collection until his retirement in 2001.

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