Orford Ness: the Black Beacon and associated power house

Summary

The Black Beacon of c.1928 built at Orford Ness to house an experimental rotating radio beacon transmitter, converted into an exhibition space in the late-1990s.

Reasons for Designation

The Black Beacon of 1928, and its associated power house, are listed at Grade II for the following principal reasons:
* Architectural interest: the building is a bespoke, perhaps unique example of an inter-war military experimental structure and little altered;
* Historic interest: national historic interest as a building associated with the inter-war military activity on Orford Ness where innovative, experimental military technologies were developed throughout the C20 and which contributed immeasurably to the nation's history;
* Group value: the Black Beacon has considerable group value with other listed Orford buildings and with the scheduled Atomic Weapons Research Establishment test structures on Orford Beach.

History

Orford Ness is sited on the Suffolk coast; it is the largest vegetated shingle spit in Europe and stretches for about 10 miles (16 km) with a maximum height above sea level of around 4m (13ft). To the west the spit is separated from the mainland by the River Alde-Ore. The spit is divided into two by a channel known as Stoney Ditch, aligned east-west. Prior to the C20, Orford Ness was a rarely visited place; the main economic activity was animal grazing on reclaimed marsh land.

In 1915 the Armament and Experimental Flight of the Royal Flying Corps (later known formally as the Aircraft Armament and Gunnery Experimental Establishment) established a flying field on King’s Marshes to the west of the ditch, now known as the Airfield Marshes, serviced by a range of ancillary buildings arranged along a single track known since 1993 as ‘The Street’, on which ran a narrow-gauge light railway which led back to the jetty. Its main areas of investigation were machine guns and gun sights, bombs and bomb sights, navigation and aerial photography. The largest buildings were two Bessonneau-type aeroplane sheds, or hangars, (demolished) but there were a number of temporary hangars along the southern edge of the flying field. To protect the station from flooding a Chinese labour battalion was drafted in to construct a seawall; German prisoners of war were also held on the spit and used in construction work. By the end of the war the establishment numbered about 600, but after the signing of the armistice the establishment was closed and placed on a care and maintenance regime.

From 1924 the airfield was re-occupied as a satellite station of the Airplane and Armament Experimental Establishment based at Martlesham Heath. During their tenure, a number of structures were constructed on Orford Beach. Due to its remoteness one of the main activities at Orford Ness was the investigation of bomb ballistics; the study of the flight of objects moving under their own momentum and the force of gravity. In 1928, the Black Beacon was constructed to the west of the lighthouse (Grade II) and approximately 400m to the south of the Bomb Ballistics Building. The building housed an experimental rotating radio beacon to aid marine navigation; lying to its north is the associated power house. Other experimental work continued into the inter-war period on Orford Ness. In 1935, a small experimental radar team arrived and conducted experiments that were critical in proving the value of this technology.

Between 1953 and 1971, the spit was occupied by the Atomic Weapons Research Establishment. Its primary task was environmental testing to simulate the conditions that nuclear weapons and their components might experience during trials and in service use. Here science and high politics merged, with investigations that were crucial to the credibility of the United Kingdom’s nuclear deterrent forces, the cornerstone of Cold War defence policy. The last trial took place on 9 June 1971 and the establishment closed on Friday 1 October 1971. On 24 July 1972 Orford Ness formally passed from AWRE to No.2 Explosive Ordnance Disposal Unit of the RAF. In the following decades they worked to clear the range of unexploded munitions and brought other munitions onto the spit for destruction. This work ceased about 1986, although many unexploded munitions still remain on Orford Ness. Following negotiations with the Ministry of Defence, the National Trust acquired Orford Ness in 1993.

When the National Trust bought Orford Ness, the Black Beacon was dilapidated. The Trust sympathetically restored the structure which houses an exhibition and is open to the visiting public.

Details

Constructed in 1928 as part of the Bombing Experimental Establishment, refurbished by the AWRE during the 1950s and converted into an exhibition space in 1995.

MATERIALS
A wooden superstructure on a concrete plinth, re-clad in weatherboarding.

PLAN
The Black Beacon has an octagonal plan.

EXTERIOR
The concrete base extends to 2.9m in height and has buttresses to each corner. The upper storeys of the tower are timber framed and covered by tarred weather boards. The building has a felt roof and is protected by a lightning conductor attached to the east side. In the north and south elevation of the Black Beacon is a 4-light wooden casement window with a tile sill protected by an iron grille. To the west is an abutting brick entry porch. To the north a set of double wooden outward opening doors give access to the west side of the octagonal base. Entry to the beacon is at first floor level by a modern flight of wooden and steel stairs. Its first floor is lit by wooden, 4-light windows. On the second storey are hinged observation ports on all sides.

INTERIOR
Within the porch are remains of electrical switch gear. The interior of the Black Beacon and generator building house an exhibition, but no longer contain equipment relating to their previous functions.The timber central drive shaft is original to the beacon use, however.

SUBSIDIARY BUIILDING
Adjacent to the Black Beacon is the rectangular power house, subsequently used as a workshop. The generator building is brick built and measures c.8m x 6m with gable ends lit by wooden ocular windows, and to the north probably retains its original wooden windows. Later modifications include the addition of a porch, and an outshot to the east that has subsequently been removed.

Sources

Other
Cocroft, W and Alexander, M, Atomic Weapons Research Establishment, Orford Ness, Suffolk Survey Report, October 2009, Research Department Report

End of official list entry

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