MARCH 12, 2025 – The 309th Aerospace Maintenance and Regeneration Group, better known as the “boneyard,” contains nearly 4,000 aircraft and 6,650 aircraft engines, making it the largest aircraft storage and preservation facility in the world.
AMARG, located at Davis-Monthan Air Force Base in Tucson, Arizona, is creating efficiencies and readiness for the military through its five core missions, said Robert Raine, a retired naval officer and AMARG public affairs director.
First is storage and preservation.
The site was chosen because Tucson’s environment is conducive to reducing rust and corrosion. Additionally, its hard soil makes it possible to move aircraft around without having to pave the storage areas, Raine said.
Preservation is accomplished by taping and spraying each aircraft with sealant designed to keep animals out, reduce corrosion and keep the aircraft about 10 degrees cooler than outside temperatures, which can be extremely hot in the summer, he said. The sealant can easily be removed if needed.
Also, engines stored in engine cans are sealed with nitrogen because oxygen has a corrosive effect, Raine said.
Second is aircraft regeneration.
Regeneration means returning the aircraft back into service, Raine said.
For example, two B-1 Lancer heavy bombers in the boneyard were returned to the Air Force and are now flying again. Also, C-23 Army Sherpas were regenerated and given to the U.S. Forest Service, and B-57 bombers were given to NASA for high-altitude coverage that included following in the path of last year’s eclipse.
Some aircraft are regenerated into unmanned aerial targets, Raine said. Nearly 1,100 aircraft — F-102 Delta Daggers, F-100 Super Sabres, F-106 Delta Darts, F-4 Phantom IIs and F-16 Fighting Falcons — have been processed for drone conversion in the 48 years since this program began.
Third is parts reclamation.
In the past year, about 10,000 parts worth around $500 million were given to the services, Raine said. Had those parts been purchased new, they would have cost considerably more, and the ordering process would have been time-consuming. Also, some parts are no longer manufactured.
“We’re not an infinite source of parts, but we’re often the only source of parts,” he said.
Fourth is disposal preparation.
Disposal is done when the aircraft and its parts are no longer needed, Raine said. Contractors shred the aircraft and sort through the shreds for aluminum, copper and exotic metals. These valuable metals cover the cost of shredding. If the salvaged metals exceed the cost of the shredding operation, the contractors will cut a check to the Treasury Department.
Fifth is depot-level maintenance.
Sometime an aircraft will need a weapons system or structural repairs, Raine said. Technicians, engineers and mechanics install upgrades, and the aircraft is expeditiously returned to the force.
Currently, a temporary aircraft maintenance shelter is under construction and almost completed.
“This will enable us to expand operations to take on additional projects and meet increasing demands. This new facility is part of a broader organic industrial base initiative aimed at enhancing self-sufficiency to ensure we have the resources, capabilities and workforce required for sustaining long-term readiness,” Raine said.
Besides military parts and aircraft, the boneyard also stores aircraft from other agencies, including the Department of Homeland Security, NASA, Forest Service, National Science Foundation and Smithsonian Institution. AMARG also stores aircraft for allied nations.
Additionally, AMARG maintains more than 270,000 line-items of aircraft production special tooling and special test equipment.
“This facility is a key force multiplier for the Department of Defense and continues to allow the United States to rapidly adjust to the global environment, national security threats and fiscal realities,” Raine said.
AMARG continues to strive to deliver excellent, safe and compliant maintenance and repair as well as overhauling logistics, storage and support services, Raine said.
The boneyard has been in existence since 1946, when wartime B-29 bombers and C-47 transport aircraft were stored there.
When the Soviet Union closed road, rail and canal traffic into Berlin in 1948, approximately one fourth of the stored C-47 cargo aircraft were withdrawn from storage and returned to flying service in support of the Berlin Airlift, he said.
In the early 1950s, AMARG withdrew and regenerated nearly 150 B-29s to support bombing missions in North Korea, as well as more than 80 B-29s to provide the United Kingdom with an interim long-range strike capability between the Avro Lincoln heavy bomber of World War II and arrival of the English Electric Canberra jet.
In 1991, AMARG oversaw the elimination of the last 443 ground-launched cruise missiles as part of the Intermediate Nuclear Forces Treaty, along with the elimination of 314 B-52 bomber aircraft begun under the Strategic Arms Reduction Treaty.
“AMARG’s long history of commitment to high standards, enhancing force readiness, and supporting America’s warfighters has earned the command the title, America’s National Airpower Reservoir,” Raine said.
By David Vergun, DOD News