Site Records

Site Name: RAF Patrington - WW2 GCI (Happidrome) Radar Station

Patrington Haven
East Yorkshire
OS Grid Ref: TA29722036

Sub Brit site visit 24th July 2004

GCI radar was used for guiding night fighters onto attacking bombers. It had three stages of development: 'mobile', 'intermediate transportable' and 'final'. Early stations (from 1940) had equipment on wheeled caravans and temporary wooden hutting; these were replaced by intermediate stations which had the aerial arrays mounted above and below a wooden gantry, with operations carried out from wooden huts. Final stations, built from 1942 onwards, had brick operations blocks, known as 'Happidromes'. These stations had a single rotating aerial array with the transmitter and receiver housed in a well underneath.

A typical happidrome reporting hall

GCI stations were fitted with a Type 7 radar initially operating on a frequency of 209 MHz, though later equipment operated on 193 and 200 MHz. This was a parallel development of the Chain Home Low (CHL) equipment by the addition of a height-finding capability and a Plan Position Indicator (PPI) display. In a PPI display the cathode ray tube is scanned radially from the centre of the rim of the tube face. The angle of the scan is synchronised to the rotating aerial and the intensity of the beam is modulated by the signals received from the aerial.

The effective range of a GCI station was 90 miles with a range of 30 miles at 1000 feet. In order to provide communication between the controllers in the Happidrome and the intercepting aircraft, two VHF/UHF multi-channel radio transmitter and receiver blocks were built at remote sites on Beaconsfield Farm, just over a mile to the north east of the technical site. The blocks were remotely sited to stop interference and swamping of the radio signals by the radar arrays.

Happidrome reporting hall - from the Controllers Cabin

Each radio site consisted of three buildings, the operations building, a standby set house and a rest room. GCI stations also provided information for anti-aircraft (HAA) gun sites.

The Domestic camp was at Haven Side (now Patrington Haven), between the technical site and the radio sites on Beaconsfield Farm. This consisted of the station headquarters, officers, senior NCO's and airmen's accommodation and messes, MT yard and garages, kitchen and mess facilities, stores, sick quarters, NAAFI, chapel, guardhouse etc.

The end of war report shows both the Type 7 (GCI) and Type 21 (Height finder) radars as being operational. In 1947 RAF Patrington (Station Code OG87) became the Northern Sector Operations Centre, controlling all the radar stations in Northern East England.

For further information and pictures of RAF Patrington WW2 GCI radar station click here

Home Page