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Orford Ness was a site of the development, testing and operation of radio and Radar technologies for military purposes for many years.


As mentioned in Military history, above, Robert Watson Watt and his team conducted early field trials of Radar (Radio Detection and Ranging) on the Ness from 1935. Following its successful trials, his team relocated to a bigger site at nearby Bawdsey where their innovative efforts resulted in the highly successful 'Chain Home’ system, and its great benefit obtained during the Battle of Britain (not part of IRGON’s research).


In addition, four 'Over the Horizon Radar' (OTHR) systems were tested and then implemented on Orford Ness during the Cold War. Each of these four ‘variants' had different objectives/targets. These could include the detection of distant Russian atmospheric nuclear detonations, missile launches or high-speed aircraft. Little is publicly known about three of these variants, but Cobra Mist, below, is well documented.


In 1960, a locally designed and operated experimental OTHR installation located in the marshes of Orford Ness detected the French nuclear tests from the Sahara see IRGON Research, Nuclear Test Detection - French Sahara.

In 1964, an American-supplied OTHR variant called ‘Chaplain’ was installed on a 50m diameter concrete ring in the shingle area. Operated by UK military personnel, it monitored Soviet Union airspace 24/7 to detect nuclear detonations and missile launches see IRGON Research, Nuclear Test Detection - Chaplain.

IRGON has been given de-classified memos that say that in 1959 ‘Zinnia', another OTHR system, was located on Orford Ness before 1964. Some information about Zinnia appears to remain classified, but Zinnia remains part of our research plans.

Cobra Mist, a USA designed and operated OTHR system, was built on the northern half of Orford Ness. Balfour Beatty completed its construction by mid-1971, and, following operational trials conducted by technical contractor SCA, it was handed over to the USAF for operation in February 1972.  However, detection problems were experienced due to unwanted ‘noise’ and Cobra Mist was suddenly shut down in June 1973. 

Most aspects of Cobra Mist's design, construction and operational difficulties are well documented, but IRGON is looking into some newly found, and less well-known, aspects.

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