Former RAF Faldingworth atomic bomb store: BD Fissile Core Storage Building

Summary

A Type B nuclear fissile core storage hutch dating to the early 1950s and built to the designs of the Air Ministry.

Reasons for Designation

The fissile core store at the former RAF Faldingworth, dating to the early 1950s, is listed at Grade II* for the following principal reasons:

Architectural interest:
* as an exceptionally rare survival of a mid-C20 military structure built for a specific purpose, making use of reinforced construction techniques and materials;
* as key physical evidence for the development of the UK’s first nuclear weapon technology.

Historic interest:
* as an exceptional survival from the very first development programme for atomic weapons in the United Kingdom, including of the earliest attempts to store plutonium bomb cores and the level of technical expertise thereby required.

Group value:
* as part of a group of buildings which collectively have major historic significance.

History

The built and archaeological remains of the Cold War (1946-1989) are the physical manifestation of the global division between capitalism and communism that shaped the history of the late C20. Nuclear weapons were the defining technology of the Cold War, firstly as atomic fission weapons, and later as more powerful hydrogen fusion weapons. Both types are technologically complex, expensive and dangerous products which required specialised, secure storage and handling facilities. These took the form of purpose built storage and maintenance units and special storage areas, on airfields where aircraft cleared to carry nuclear weapons were permanently stationed or might be deployed in time of war.

The evolution of nuclear bomb stores in England illustrates changing deployment strategies throughout the Cold War by the Royal Air Force and the United States Air Force - both by its Strategic Air Command deterrent forces and by its tactical forces committed to NATO. The siting of nuclear bomb stores on airfields, for example, demonstrates NATO's willingness to store nuclear weapons close to the units that would use them. Initial RAF plans to hold atomic bombs at two central stores were quickly overtaken by the need for faster response times, and small atomic bomb stores were instead provided on nine of the ten main V-bomber nuclear strike airfields. These stores were initially supported by other central stores and so were configured to hold no more than twelve bombs. In the first generation of atomic bomb stores there is a close correlation between the physical infrastructure and the bombs they were designed to house, and the technology of early atomic bombs is reflected in the design and size of their stores.

The Blue Danube was the first dedicated British atomic bomb programme, as well as the colloquial name for the bombs themselves. With the increasing tensions of the late 1940s and early 1950s between the USSR and the USA, the decision was taken to instigate and develop the United Kingdom’s own atomic programme. As well as the huge technical challenges that would bring, there were also extensive logistics issues to tackle, not least because the weaponry being dealt with was both entirely unknown and very unpredictable in the early days. As part of the programme therefore, a significant expansion of existing airfields was required in the early years of the 1950s, in order to both store safely, and if required to deploy the new weaponry.

In the early days of the UK atomic programme there was a great deal of learning by trial and error as there was no precedent for handling weapons of this type or magnitude. From the 1950s sites were selected to be the dedicated storage and maintenance facilities for the new weapons. The first of these was the former RAF Faldingworth in Lincolnshire. A second central storage facility was established at RAF Barnham in Suffolk. Further supplementary storage facilities were established at Wittering, Coningbsy, Waddington, Scrampton, Honington and Cottesmore.

RAF Faldingworth had been established in 1936 as part of the airfield expansion programme in the years before the Second World War. Initially a decoy airfield it became a weapons store following the war, prior to being selected as one of the central stores for Britain’s nuclear arsenal. It was also the operational storage base for nearby RAF Scrampton where there was insufficient space to establish a storage facility there. Faldingworth was under the operational control of No 2 Maintenance Unit. Both Faldingworth and Barnham have similar layouts, with the inner compound being a five sided space protected by an outer metal fence and an inner concrete panel fence, both topped with razor wire. The outer compound contained ancillary and support buildings. These were mainly occupied by the RAF Police, who were the only permanent presence on the storage sites. Dogs were allowed to run free within the inner compound, which was also guarded by observation towers.

The first British Nuclear weapons were free fall bombs, produced to Air Ministry operational requirement OR.1001; the original issue date was August 1946. The very first bombs used a type of fissile core comprising Plutonium with a Polonium initiator. For safety reasons they were stored separately from the other bomb components. This led to the creation of dedicated ‘hutches’ to store the fissile cores which can be found surviving at the central and early airfield bomb stores. At Faldingworth two of the hutches survive. These are ‘Type B’ which means they were built to house two cores in each hutch. The compound has areas of tree planting, which helped to conceal the core stores. The remaining components were stored in large storage bays also within the inner compound which were designated as DD. As the weaponry developed the handling became more assured and the facilities were developed and adapted as required to take account of the changes. On other bases such as Coningsby this involved the construction of new storage bays designated respectively as D2 followed by D3. The central storage bays at Faldingworth continued in use during the 1950s and 1960s.

In the late 1960s the UK changed its strategic nuclear deterrent from bombs to ballistic missiles. This made the storage facilities at Faldingworth redundant. The base was closed by the RAF in 1972. Following its disposal by the MoD the site was taken over by BMARC (British Manufacture and Research Company) and latterly BAE Systems and became a munitions factory. The production buildings, testing and storage facilities were constructed at this time, including a series of reinforced concrete magazines to the north east of the site and a large testing range.

Details

A Type B nuclear fissile core storage hutch dating to the early 1950s and built to the designs of the Air Ministry.

MATERIALS: the hutches are built of reinforced concrete walls standing on a brick plinth, with an asphalt covered roof. The door is composed of metal-plated timber boards.

PLAN: the hutch is rectangular on plan.

DESCRIPTION: the hutch is a small single-storey structure with an overhanging flat roof. It is near square, being 3 metres by 2.5 metres. The single leaf metal-plated door is located in the north elevation and is reached by a low concrete rampway which joins to the remains of a concrete pathway which interconnected the hutches. The walls are rendered internally with gritless plaster, with four small ventilators inset at the sides and to the rear. The doors are of wood protected externally by a steel sheet, and are secured by a combination lock and internal, vertical locking bar operated by an external handle. The cores themselves were stored in two key-hole shaped holes in the ground which have since been filled in with concrete, but are still discernible. There is a radiator against the rear wall. Electrical fittings, including the automatic door lock which allowed opening and closing from the control, remain in situ but are not functional.

Sources

Books and journals
Cocroft, WD, Thomas, RJC, Cold War: Building for Nuclear Confrontation 1946-1989, (2003)

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