Aircraft boneyard is an American term for a storage area for aircraft that are retired from service. Most aircraft at boneyards are either kept for storage or turned into scrap metal. Deserts, such as those in the Southwestern United States, are good locations for boneyards since the dry conditions reduce corrosion.
While some are privately owned and operated, others belong to the military, such as the 309th Aerospace Maintenance and Regeneration Group at Davis-Monthan Air Force Base in Tucson, Arizona.
After aircraft are put into boneyards, many are stripped of useful parts. Engines, most electronics, munitions, and wiring are removed to be recycled or to be kept in warehouses. These may serve as replacement parts for aircraft that are still flying or may be used for reconditioning if and when the aircraft are called back into active duty. These parts along with the stripped aircraft may be sold to other countries.
Depending on the demands of the military or for commercial purposes, an aircraft or a whole squadron of them may be put back into active duty. The aircraft have to be reconditioned and tested so they are safe to fly. The reconditioning process includes putting in new avionics, electronics, safety measures, testing and painting. Reconditioning of old aircraft is usually a cheaper way of getting more aircraft into service than buying new ones, and saves the United States billions of dollars annually.