Davis–Monthan Air Force Base (DM AFB) (IATA: DMA, ICAO: KDMA, FAA LID: DMA) is a United States Air Force base 5 miles (4.3 nmi; 8.0 km) south-southeast of downtown Tucson, Arizona. It was established in 1925 as Davis-Monthan Landing Field. The host unit for Davis–Monthan AFB is the 355th Wing (355 WG) assigned to Twelfth Air Force (12AF), part of Air Combat Command (ACC). The base is best known as the location of the Air Force Materiel Command's 309th Aerospace Maintenance and Regeneration Group (309 AMARG), the aircraft boneyard for all excess military and U.S. government aircraft and aerospace vehicles.
Davis–Monthan Air Force Base is a key ACC installation. The 355th Wing (355 WG) provides A-10 Thunderbolt II close air support and OA-10 forward air controllers to ground forces worldwide. The 355 FW is also the host unit, providing medical, logistical, mission and operational support to all assigned units. The 355 FW is also the sole formal training unit for the A-10 aircraft, providing initial and recurrent training to all U.S. Air Force A-10 and OA-10 pilots, to include those in the Air Force Reserve Command (AFRC) and the Air National Guard (ANG). The 355th is also ACC's executive agent for INF and START treaty compliance.
One of the wing's tenant units, the 55th Electronic Combat Group (55 ECG), is a geographically separated unit (GSU) of the 55th Wing (55 WG) at Offutt AFB, Nebraska and is an ACC unit tasked to provide offensive counter-information and electronic attack capabilities in support of U.S. and Coalition tactical air, surface, and special operations forces with its Lockheed EC-130H Compass Call aircraft and employing the EC-130H in tactical air operations in war and other contingencies worldwide. The 55 ECG also provides initial and recurrent training to all EC-130H Compass Call pilots, navigators and air crew.
Two other major tenants, the 563rd Rescue Group , and the Air Force Reserve Command's (AFRC) 943rd Rescue Group (structured as a GSU under AFRC's 920th Rescue Wing at Patrick Air Force Base, Florida), are tasked to provide combat search and rescue (CSAR) and personnel recovery (PR) support worldwide.
Perhaps the most prominent tenant is the 309th Aerospace Maintenance and Regeneration Group (309 AMARG) of the Air Force Material Command (AFMC). As the main location for the 309 AMARG, Davis–Monthan AFB is the sole aircraft boneyard for excess military and U.S. government aircraft and other aerospace vehicles such as ballistic missiles. Tucson's dry climate and alkali soil made it an ideal location for aircraft storage and preservation.