During WWII, RAF St. Margaret’s was a radar site and formed part of the CHEL (Chain Home Extra Low) radar system. It continued in this role after the war and became part of the 1950s ROTOR project, a nationwide system used to detect an incoming Soviet air attack. By this time, the site was known as Swingate, No 1 Signals Unit. An innocuous bungalow served as the guard house to the site, typical of all ROTOR sites.

It remained this way until 1958 when the unit was disbanded. 

 

The ROTOR system was designed to detect Soviet aircraft, which were expected to be carrying nuclear weapons, but this was soon superseded by ICBM (missile) delivery from land-based sites and, crucially, from submarines. Detection systems changed in response to this. St. Margaret’s bunker and surrounding site were superfluous, and in 1958 the site passed into Care and Maintenance under RAF Sandwich, from there to RAF Manston. In 1970 the site was purchased by Kent County Council, while the bungalow was purchased privately.