Air Force Plant 44 is southwest of Tucson and is operated by Raytheon Missile Systems Company [Hughes Aircraft]. It covers 2,900 acres (95% government-owned) and 2.1 million square feet (51% government-owned, including the manufacturing space and Final Assembly and Checkout [FACOI facilities). The main plant complex was built in 1951 by the Del Webb Corporation for Hughes Aircraft Co. Hughes then sold the plant to the U.S. Air Force (USAF), but continued to operate it. At that time it was the prime production plant for the Falcon family of air-to-air missiles. In 1954, the plant was expanded by adding land and building the FACO facility for the Navy’ s Walleye Missile. Test cells and explosive storage magazines for the Phoenix and AMRAAM programs were added later. In the mid-1980s over 1,900 acres were transferred to the state, Tucson, and the Air National Guard. At that time, AFP 44 supported the TOW, Maverick, Phoenix, ARBS (Angle Rate Bombing System), and AMRAAM programs. The FACO facility is used for Maverick and TOW missile assembly.