Burtonwood was for many years the most important air base in the United Kingdom, at least in terms of its size and the amount of traffic which passed through it. Built for the RAF but taken over by the USAAF during the war, it played a major role in that war and then in the US commitment to the protection of Europe during the Cold War. The main east-west runway was extended to 9,000 feet while the others fell out of use, and a new control tower and terminal building opened in 1955. Then disaster struck, when the site began to suffer from mining subsidence. MATS left for Mildenhall in 1958 and by the following year the USAF had gone completely, although Burtonwood continued in use by the US Army until the early 1990s.