A Thor missile satellite base established at the former World War II airfield of RAF Harrington, constructed in 1959 and operational until 1963. Partially cleared in the late C20.
Reason for Listing
The Thor missile site at former RAF Harrington, Northamptonshire, is designated at Grade II, for the following principal reasons:
* Architecture: Although of a standard design, the Thor structures at Harrington fluently express the functionality and distinctive arrangement of a Thor missile satellite base.
* Intactness: The components and infrastructure of the Thor base survive sufficiently intact for their operational arrangements to be discerned.
* Historic Interest: The Thor missile site has international historic significance because of its association with world events of the Cold War period.
* Rarity: Only 20 Thor sites were established in England, of which the Harrington base is one of the most intact.
* Context: The functional and tactical association with the main Thor missile station at North Luffenham contributes to the special interest of the Harrington base.
Harrington airfield was built as Station 179, between 1942-44, by the 826th and 852nd Engineer Battalions of the US Army, as a Class A airfield intended for flying the B-17 Flying Fortress. In 1943, the airfield was handed over to the RAF as a satellite training station for the 84th Operational Training Unit stationed at Desborough, flying Wellington bombers. In 1944, the station was chosen for the Carpetbagger operations of the 8th USAAF Special Operations Group delivering agents and supplies to Resistance Units in occupied Europe and later to the advancing allied army until the German surrender in May 1945. The American Airforce withdrew from Harrington later in 1945, after which the airfield was held on a care and maintenance programme and used for storage purposes until the late 1940s when much of the airfield was returned to farmland.
RAF Harrington found a new military purpose in 1959, when it became a satellite Thor missile site under the control of RAF North Luffenham in Leicestershire. Thor missiles were the first operational Intermediate-range Ballistic Missile (IRBM) system deployed by the West during the Cold War. With a range of 1,500 nautical miles, Thor missiles were approximately 20m (65ft) long and 2.5m (8ft) in diameter powered by propellant rocket fuel controlled by two motors. Developed by the United States (US) Government between 1955-1959, the proposal to deploy Thor in Britain as well as the US was put before the British Government in 1957. At the time Britain was developing its own IRBM, Blue Streak, which would not be operational for some time. Final agreement to locate Thor in Britain was reached between the Prime Minister, Harold Macmillan, and President Eisenhower at the Bermuda Conference in 1957. The rockets were to be British property, manned by the RAF who would be trained for the task by the USAF, but the nuclear warheads would remain under US control. Macmillan reported to Parliament that the decision to use Thor against the Communist east would be made jointly by the two countries.
A total of 60 missiles were deployed at 20 sites in the East of England from 1958 under the codename 'Project Emily'. There were four main bases located on pre-war permanent airfields; RAF Feltwell, RAF North Luffenham, RAF Hemswell and RAF Driffield. At each base an adapted hangar was used to receive the missiles, store the servicing equipment and conduct inspection and maintenance. Usually located on the opposite side of the airfield, the Thor compounds at the main bases had a Surveillance and Inspection Building and a Classified Storage Building, partly surrounded by earthwork berms, where the warheads were inspected and stored. Every main base had four satellite stations, each with their own Squadron. The launch areas at the main and satellite stations were almost identical, although at the latter a smaller Classified Storage Building and Pyrotechnic Store was placed c 200m away from the nearest emplacement, protected by earthwork banks. The buildings and emplacements lay in an irregularly shaped compound surrounded by a pair of fences. Inside were crew huts, a squadron office and telephone exchange. Close to the main gate was the launch control area, an area of concrete on which the control trailer, generators and an oil tank were placed.
Exact siting of the missiles was essential to ensure the targets were reached. In addition to the precise, fixed location of the launch components each emplacement had a theodolite shed and a separate long-range theodolite set on a concrete pillar surrounded by brass survey points. At the opposite end of the emplacement two short-range theodolites were mounted on a metal platform near to the launcher erector which lay at the centre of each emplacement and was secured to a metal cage set in concrete. Here the missiles, which were stored horizontally on a trailer, were raised to a vertical position. The two fuels which powered the rocket, kerosene and liquid oxygen, were stored in fuel pits on either side of the erector and pumped separately through pipes suspended in concrete conduits. A separate liquid oxygen dump tank was located to the rear of the blast walls in case the fuel needed to be rapidly discharged from the missile. At the far end of each emplacement were two 'L' shaped blast walls.
Thor missiles could be brought to operational readiness in 15 minutes after receiving the authorised and authenticated order to launch. Strict understandings about the operational control of the missile included an agreed British and US launch through a dual key system and a veto for each Government. Although Thor deployment in Britain was an interim measure, their presence played an important part in the Cuban Missile Crisis of October 1962, the most tense period of the Cold War, when fifty nine of the sixty missiles were made ready. Thor was phased out in England between April and August 1963, just short of their anticipated 4 year life-span, North Luffenham being the last site to close.
At Harrington, the buildings, runways and most of the roads and taxiways of the airfield were demolished in 1965, although part of the western perimeter track has been adopted as a bridle path. A memorial to the American servicemen who gave their lives during Operation Carpetbagger was erected on a former aircraft dispersal point in 1987. The Carpetbagger Aviation Museum was founded in 1997, housed in part of the original Operations Building in the former administration area of the airfield. The Thor site in the south-west area of the former airfield is surrounded by farmland. Research and fieldwork conducted as part of the Monuments Protection Programme (MPP) in 1998, aerial photographic evidence and a recent site inspection provide a clear understanding of the survival of the site.
Reinforced concrete bases and structures.
The Thor missile site lies in an isolated position surrounded by farmland, south-east of the former position of the airfield's runway. The three launch emplacements are arranged in an unusual linear configuration along a plateau. The compound is not extant, but can be traced; the concrete pad for the Launch Control cabins lies to the east and the Pyrotechnic Store and Classified Storage Building lie to the west within earthwork bunds.
The southern (no.1) and central (no.2) emplacements retain most of the concrete base, the blast walls, launcher erector mounting, fuel dump pit footings and partially standing theodolite sheds. Part of a theodolite pillar rests against the shed of emplacement no.2. However, the concrete base of the northernmost emplacement (no.3) has been partly removed at the west end, and there has been further loss to the components of the emplacement, including the theodolite shed, although the blast walls and launcher erector mounting bolts survive.
Source: English Heritage
Listed building text is © Crown Copyright. Reproduced under licence.