fully operational until March 1974. By that time the strategic threat had changed dramatically, and air strikes on the UK once again became a possibility. Linesman's single centralized L1 command centre was vulnerable, and the sea-side radars even more so. Money set aside to improve Linesman was instead directed to building its replacement, UKADGE. UKADGE was further expanded with Marconi Martello and the Type 85s stood down in the 1990s. History ROTOR As the threat of German air attack on the United Kingdom faded in 1944, the wartime network of Chain Home (CH) and AMES Type 7 sites was progressively turned off, a process that rapidly accelerated with the end of the war in 1945. At the time, it was believed it would be at least another ten years before there would be another major war, so the Royal Air Force turned its attention to research and development of radar as they felt there was little reason to deploy any systems when better ones would be available by the time they would be needed. Various events in 1949, notably the Berlin Airlift and the testing of the first Soviet nuclear bomb, led to studies to rapidly re-implement the air defence system. Most influential was the Cherry Report, which outlined a set of equipment upgrades at existing WWII-era radar sites to improve their performance, along with an entirely new communications network to coordinate the response. Adopted as ROTOR, the new system split the UK's airspace into six "sectors" controlled from underground bunkers using thousands of miles of telex lines to pass information around. ROTOR planned for a staged deployment in several stages. The first re-used existing radars and control methods and was to be operational by 1952. The second would replace the Chain Home radars with a new Microwave Early Warning (MEW) set beginning around 1957. More stations would be added and the communications systems updated over time, with the final network being fully implemented by the late 1950s. Master Radar Stations The entire ROTOR plan was seriously upset by an experimental radar known as "Green Garlic" that was developed at the Telecommunications Research Establishment. This combined an experimental low-noise receiver with a new high-power cavity magnetron and a lash-up antenna. The system more than doubled the effective range for early warning, and when married to a more suitable antenna, provided good detection of bomber-sized aircraft out to . This filled