Atomic Weapons Research Establishment. Orford ... - English Heritage

Project 441- L Cobra Mist
Figure 13: Cobra Mist site 23 July 1997. NMR 15704/25 (c) Crown.copyright.NMR
In the late 1960s, and unconnected with AWRE, Orford Ness was selected as the
site for an experimental over the horizon radar system (Figure 13). In essence it was
designed to extend the range of conventional radar detection techniques by bouncing
radio signals off the ionosphere. In theory it should be possible to detect any disturbance
to these signals caused, for example, by the launch of a missile or the passage of an
aircraft. The northern end of the spit selected for this installation had been one of the
main target areas and was heavily disturbed by practice bombing. Unexploded ordnance
clearance began in 1967, by July 1971 most building work was completed and fitting
out was finished by February 1972. Testing began almost immediately, it was, however,
quickly discovered that there were unsolvable problems with background interference
and the project was abandoned in June 1973 (Cocroft and Thomas 2003, 135-9). The
facility was later adapted for use by the BBC World Service and since 1997 has been
managed by VT Merlin Communications Ltd.
Closure of AWRE Orford Ness
With the introduction of the WE177 and the Polaris system, there was relatively little new
work in prospect and in April 1969 the decision was announced to close Orford Ness and
to move many of its functions to Aldermaston. The last trial took place on 9 June 1971and
the establishment closed on Friday 1 October 1971 (Kinsey 1981, 115). On 24 July 1972
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