Summary
An Anti-Aircraft Operations Room built c1951 for the Ministry of Defence to a design drawn up by the Ministry of Works.
Reasons for Designation
The Former Anti-Aircraft Operations Rooms at Frodsham, Cheshire, completed in 1951, is listed at Grade II for the following principal reasons:
* Intactness: a substantially intact early 1950s anti-aircraft operations room which has experienced only minor alteration since being built, with good survival of original internal fittings and fixtures.
* Historic interest: it represents the early transition of Cold War British defence policy developing from Second World War practices but taking into account the use of jet aircraft and atomic bombs. The later use of the structure reflects the different phases of civil defence and emergency planning during the Cold War;
* Architectural interest: a building which expresses through its monumental and robust form the threat posed by the atomic bomb and the necessary measures to protect its occupants from the effects of nuclear attack. The plan illustrates the needs and functions of the tactical command of radar controlled anti-aircraft defences, as envisaged during the late 1940s. The structure is representative of design thinking before the introduction of the Hydrogen Bomb in the mid-1950s;
* Rarity: one of only four Anti-Aircraft Operations Rooms surviving in England that were built on the surface, but protected from blast, heat and the initial radiation burst by being set back into the slope of a hill.
History
Anti-Aircraft Operations Rooms (AAOR) formed an integral part of the United Kingdom's anti-aircraft defences during the early 1950s and are a physical representation of early Cold War defence based upon the command and control experience gained during the Second World War. Thirty-two gun defended areas (GDA) were established in the United Kingdom, of which 23 were in England. Each GDA was commanded by an anti-aircraft operations room that controlled the automated gun sites built around the periphery of major conurbations, ports, and centres of armament production. It was an integrated defence system designed to counter the threat posed by manned Soviet bombers carrying free-fall atomic bombs. By the mid-1950s, advancing technology and the threat of long-range ballistic missiles, rendered the system obsolete. Government policy shifted from one of ‘point-defence’ to one of nuclear deterrent, and following the publication of the 1956 Defence White Paper that announced the change in policy, Anti-Aircraft Command was abolished.
The former Anti-Aircraft Operations Room (AAOR) at Beacon Hill, Frodsham was one of twenty-eight purpose-built examples constructed for the Royal Artillery between 1950 and 1951. It was under the command of 4 Group, 79 Brigade and controlled the gun sites in the Mersey Gun Defended Area. The operations room received long-range radar reports of the approach of hostile aircraft from the RAF’s Master Radar Stations. A trial Yellow Yeoman (Type 82) tactical control radar associated with the AAOR would then pick up and track the targets before they were allocated to the automated gun sites within their GDA.
Their role was short lived, and following the abolition of Anti-Aircraft Command in 1956, the bunker was acquired by Cheshire County Council in 1961 which converted it into a Civil Defence Training Centre. This new use was also short lived as the Civil Defence Corps was disbanded seven years later in 1968. Having stood empty for some time, the building was refurbished in 1986/87 and became the Cheshire County Standby Emergency Centre and the Cheshire Fire Brigade County Standby Control Centre; the main control being at Winsford.
Details
An Anti-Aircraft Operations Room built c1951 for the Ministry of Defence to a design drawn up by the Ministry of Works.
MATERIALS: it is built of reinforced concrete, fitted with steel blast doors and ventilators.
PLAN: it is square in plan and comprises a two-storey semi-sunken reinforced concrete structure with a central operations/plotting room surrounded on both floors by a circulating corridor, with control cabins, offices, communications rooms, plant rooms, latrines and dormitories.
EXTERIOR: since the building was designed to resist the effects of a nuclear explosion, there are no windows and the only openings in the structure are the two entrances, ventilator grilles, the stand-by generator exhaust and a protruding ventilation flue on the roof above the plant rooms. The main entrance situated centrally in the south-east elevation is at ground level, while a second entrance in the north-west elevation is at the upper-floor level and is approached by a flight of concrete steps set into the slope of the hill. The two entrances have double steel blast-doors that are protected by open-sided concrete blast wall porches. Three round, steel ventilator grilles protected by plain projecting concrete drip moulds are situated to either side of the entrance in the north-west elevation.
INTERIOR: it is entered at the lower-floor level in the south-east elevation and the entrance leads into a lobby that functioned as the reception/security room. A dog-leg circulatory corridor gives access to a number of rooms built around the centrally positioned full height former operations room. All of these rooms bar the boiler, air conditioning, and generator rooms have been given different functions over time; their original functions included the tactical radar control room, radio-telephony room, telephone-frame room, Other Ranks (OR) and Women’s Royal Army Corps (WRAC) rest rooms. The well of the operations room is entered from the circulatory corridor by two doorways on opposing sides of the room. It is overlooked by viewing galleries at first floor level, supported on plain tubular steel columns. The galleries are accessed from the upper floor, and on the northern and southern sides are occupied by cabins which retain their curving anti-reflection Perspex windows. The blank south-eastern wall would originally have had situation tote and map boards displayed on it.
The upper floor corridor is accessed externally from the north-west entrance, doorway and internally from the lower floor by a total of five stairways protected by painted galvanised tube and steel mesh balustrades. As with the lower-floor, a series of rooms surround the operations room; including latrines, rest rooms, a NAFFI, civil servants’ room, switchboard, and various offices. Some of the original partition walls have subsequently been removed and an open dining area occupies most of the south-western side of the upper floor, while the former WRAC latrines have been converted to a kitchen. The original positions of walls are visible as witness marks on the Marley-tiled concrete floors. Most of the rooms on both floors retain their original plain wooden doors; the original box ducting for the ventilation system remains intact throughout. The original air conditioning plant and filtration system is intact, although the boiler and the stand-by generator have both been replaced by modern equipment.
