The 309th Aerospace Maintenance and Regeneration Group (309th AMARG), often called The Boneyard, is a United States Air Force aircraft and missile storage and maintenance facility in Tucson, Arizona, located on Davis–Monthan Air Force Base. The 309th AMARG was previously Aerospace Maintenance and Regeneration Center, and the Military Aircraft Storage and Disposition Center, and its predecessor was established after World War II as the 3040th Aircraft Storage Group. The 309th AMARG takes care of nearly 4,000 aircraft, which makes it the largest aircraft storage and preservation facility in the world. An Air Force Materiel Command unit, the group is under the command of the Ogden Air Logistics Complex at Hill Air Force Base, Utah. The 309th AMARG was originally meant to store excess Department of Defense and Coast Guard aircraft, but has in recent years been designated the sole repository of out-of-service aircraft from all branches of the US government. The facility has also received US-made foreign military aircraft such as the Boeing CC-137 (from RCAF for use in the E-8 JSTARS program) and the Lockheed CP-140A Arcturus (2 from RCAF). The arid climate of the region makes the 309th AMARG an ideal location for storing aircraft, as there is very little humidity in the air that would corrode metal. Furthermore, the surface is hard so that the aircraft do not sink into the ground. History The first predecessor of the 309th AMARG was established in 1946 as the 4105th Army Air Forces Base Unit (Aircraft Storage) to house Boeing B-29 Superfortress and Douglas C-47 Skytrain aircraft. Davis–Monthan Field was chosen because of Tucson's low humidity, infrequent rainfall, alkaline soil, and high altitude of , reducing rust and corrosion. The hard soil makes it possible to move aircraft around without having to pave the storage areas. In 1948, after the Air Force's creation as a separate service, the unit was renamed the 3040th Aircraft Storage Depot. In 1965, the Military Aircraft Storage and Disposition Center was organized and tasked with processing aircraft for all the United States armed forces, not just the Air Force. The Navy had operated its own boneyard at Naval Air Station Litchfield Park at Goodyear, Arizona, for Navy, Marine Corps and Coast Guard aircraft. In February 1965, some 500 aircraft were moved from Litchfield Park to Davis–Monthan. NAS Litchfield Park was finally closed in 1968. In the 1980s, the center began processing intercontinental ballistic missiles for