of the earlier RadLab. By September 1951, only months after the Charles report, Project Lincoln had more than 300 employees. By the end of the summer of 1952 this had risen to 1300, and after another year, 1800. The only building suitable for classified work at that point was Building 22, suitable for a few hundred people at most, although some relief was found by moving the non-classified portions of the project, administration and similar, to Building 20. But this was clearly insufficient space. After considering a variety of suitable locations, a site at Laurence G. Hanscom Field was selected, with the groundbreaking taking place in 1951. The terms of the National Security Act were formulated during 1947, leading to the creation of the US Air Force out of the former US Army Air Force. During April of the same year, US Air Force staff were identifying specifically the requirement for the creation of automatic equipment for radar-detection which would relay information to an air defence control system, a system which would function without the inclusion of persons for its operation. The December 1949 "Air Defense Systems Engineering Committee" led by Dr. George Valley had recommended computerized networking for "radar stations guarding the northern air approaches to the United States" (e.g., in Canada). After a January 1950 meeting, Valley and Jay Forrester proposed using the Whirlwind I (completed 1951) for air defense. On August 18, 1950, when the "1954 Interceptor" requirements were issued, the USAF "noted that manual techniques of aircraft warning and control would impose "intolerable" delays" (Air Materiel Command (AMC) published Electronic Air Defense Environment for 1954 in December .) During February–August 1951 at the new Lincoln Laboratory, the USAF conducted Project Claude which concluded an improved air defense system was needed. In a test for the US military at Bedford on 20 April 1951, data produced by a radar was transmitted through telephone lines to a computer for the first time, showing the detection of a mock enemy aircraft. This first test was directed by C. Robert Wieser. The "Summer Study Group" of scientists in 1952 recommended "computerized air direction centers…to be ready by 1954." IBM's "Project High" assisted under their October 1952 Whirlwind subcontract with Lincoln Laboratory, and a 1952 USAF Project Lincoln "fullscale study" of "a large scale integrated ground control system" resulted in the SAGE approval "first on a trial basis in 1953". The