tactically away from Germany, mainly in the United States and Canada where most of its aircraft were sourced. During the 1960s and 1970s, a very large number of jet crashes—the suffered a 36 percent crash rate for F-84F Thunderstreaks and an almost 30 percent loss of F-104 Starfighters—created considerable public demand for moving combat training centers away from Germany. As a result, the set up two tactical training centres: one, like those of many of the NATO forces, at the Royal Canadian Air Force base at Goose Bay; and the second in a unique partnership with the United States Air Force at Holloman Air Force Base in New Mexico (F-104 pilots had already been trained at Luke Air Force Base, Arizona, since 1964). Both facilities provide access to large unpopulated areas, where tactical and combat training can take place without danger to large populations. On 1 May 1996, the established the German Air Force Tactical Training Center (TTC) in concert with the United States Air Force 20th Fighter Squadron at Holloman Air Force Base in New Mexico, which provides aircrew training in the F-4F Phantom II. The TTC serves as the parent command for two German air crew training squadrons. The F-4 Training Squadron oversees all German F-4 student personnel affairs and provides German instructor pilots to cooperate in the contracted F-4 training program provided by the U.S. Air Force (20th Fighter Squadron). A second TTC unit, the Tornado Training Squadron, provides academic and tactical flying training, by German air force instructors, for German Tornado aircrews. The first contingent of Tornado aircraft arrived at Holloman in March 1996. More than 300 German air force personnel are permanently assigned at Holloman to the TTC, the only unit of its kind in the United States. The German Air Force Flying Training Center activated on 31 March 1996, with German Air Force Chief of Staff Gen. Portz and U.S. Air Force Chief of Staff Gen. Michael Ryan present. The has since stationed up to 800 personnel at Holloman for training exercises, due to limited training space in Europe. In September 2004, the announced a reduction in its training program by about 20%. By the end of 2006, 650 personnel and 25 Tornado aircraft were assigned to Holloman. Air bases In 2020, the Air Force uses 12 air bases, four of which host no flying units. In the future, Lechfeld Air Base will become