What happens when an aircraft is no longer needed? In the desert dry of the south-western US, vast ‘boneyards’ are homes to thousands of aircraft, Stephen Dowling writes.

If you find yourself driving down South Kolb Road in the Arizona city of Tucson, you’ll find the houses give way to a much more unusual view; rows of military aircraft, still and silent, spread out under the baking desert sun. On and on, everything from enormous cargo lifters to lumbering bombers, Hercules freighters and the F-14 Tomcat fighters made famous in Top Gun.

This is Davis-Monthan Air Force Base, run by the 309th Aerospace Maintenance and Regeneration Group (309 AMARG). It’s home to some 4,400 aircraft, arranged over nearly 2,600 acres (10.5 sq km). Some look like they were parked only a few hours ago, others are swathed in protective coverings to keep out the sand and dust. Inside the facilities' hangars, other planes have been reduced to crates of spare parts, waiting to be sent out to other bases in the US or across the world to help other aircraft take to the air again. To those who work here, Davis-Monthan is known by a far less prosaic name, one more in keeping with the Wild West folklore from Arizona’s earlier days. They call it The Boneyard.

Davis-Monthan is not the only aircraft boneyard in the world, but it is by far the biggest. The climatic conditions in Arizona – dry heat, low humidity, little rain – mean aircraft take a lot longer to rust and degrade.

What’s more, underneath the top six inches of dirt topsoil is a clay-like sub layer called caliche. This extremely hard subsoil allows the planes to be parked in the desert without the need to construct expensive new parking ramps, according to the 309 AMARG.

Planes are expensive things to build and maintain, but even at the end of their flying lives they still have their uses. But it takes a lot of room – and a lot of money – to store these unused planes in the kind of hangars needed to keep them warm and dry. It’s much cheaper to store them in the kind of conditions found in Tucson. That’s the reason why many of the world’s biggest aircraft boneyards are found in the dry deserts of the south-western US.

But it’s not simply a case of landing a plane at Davis-Monthan, parking it in one of the rows and handing someone the keys. Many of the aircraft are considered inactive, but have to be able to be brought back into service if need be. That takes a lot of work.

Broken bombers

The Boneyard’s workers have an exhaustive checklist. Any planes that have served on aircraft carriers have to be thoroughly washed to get rid of corroding salt. All aircraft have their fuel tanks and fuel lines drained, and flushed with a light, viscous oil similar to that used in sewing machines to ensure all the moving parts are lubricated. Then they must have any explosive devices – such as the charges that activate ejection seats – safely removed. Then, any ducts or inlets are covered with aluminium tape and the aircraft are painted over with a special easily strippable paint – two coats of black, and a final white layer to help deflect the fierce desert sun and keep the aircraft relatively cool.

Aircraft are kept at various levels of restoration – some are kept in as close-to-working order as possible if they are deemed to be needed to fly at a later date, while others are partially dismantled. Some of the aircraft stored at Davis-Monthan include retired B-52 bombers, aircraft capable of carrying nuclear weapons. As part of strategic arms limitation treaties with the Soviet Union, the B-52s were stored with their wings removed and placed next to the plane – allowing Soviet satellites to verify that the bombers had been taken out of service.

Others are used for spare parts, with the components sitting in the aircraft until they’re needed. On site is a smelter, where some of the surplus aircraft are shredded and totally recycled.

And with the original assembly lines of most of these aircraft long-since mothballed, Davis-Monthan is home to some 400,000 piece of tooling and machinery needed to create specific aircraft parts. Aircraft all over the world, not just those flown by the US, contain parts from the base’s enormous stockpile.

Post-Soviet boneyards

“As long as there are aircraft flying, military and commercial aircraft boneyards will always be necessary to keep other planes in the air,” says aviation author Nick Veronico, who has visited Davis-Monthan as well as the Mojave facility and other boneyards in the desert states.

“Each of the storage yards typically performs a variety of functions from storing aircraft that are temporarily out of service but expected to return to the fleet, to reclaiming useable parts which are inspected, overhauled, and then held until needed by active aircraft, to dismantling of the aircraft carcasses. These functions go hand-in-hand and are part of the lifecycle of an aircraft.

“I have flown on aircraft that have gone to the boneyard and provided parts to the fleet,” he says. “I’ve had the opportunity to watch parts being removed from a plane, and then having flown on an aircraft flying with salvaged parts – the exact parts I saw being removed, preserved, and installed.”

There are boneyards in Russia that contain some of the old Soviet Union’s military aircraft, but it’s fair to say the aircraft here are not in any fit state to return to the skies. The former bomber base at Vozdvizhenka, some 60 miles north of Vladivostok in far-eastern Russia, used to be home to Soviet supersonic bombers. After the end of the Cold War the aircraft were surplus to requirement – and simply left where they were parked. The once-secretive base in now abandoned, and this ghostly bomber fleet now poses for photographers who clamber through the rusted fences.

Another post-Soviet boneyard is in the Chernobyl Exclusion Zone – the area evacuated after the 1986 nuclear disaster in Ukraine. The vehicles used to help clean up the disaster area were contaminated with radiation. A line of giant Soviet helicopters has been left to rust in the fields. BBC News pictures editor Phil Coomes visited the site in 2006, on the 20th anniversary of the disaster. “After the nuclear accident at Chernobyl, many of the contaminated vehicles used in the clean-up operation were placed in graveyards in the vast exclusion zone around the reactor. Some remain there today,” he says. “The largest graveyard, Rassokha, [is] where the remains of helicopters, military and civilian vehicles and fire engines are slowly rusting away. It’s a vast site, but over the years parts have been reclaimed for spares but contamination levels vary, so souvenir hunters would be wise to keep away.” Despite the danger of radiation poisoning, many of the helicopters have been stripped of useful parts; their skeletal remains dwindle with every passing year.

In eastern California, Mojave Airport carries out a similar role for civilian aircraft that have reached the end of their operational lives. Airliners have been flown here for decades, and stored in the dry desert heat until broken up for scrap.

“Driving across California’s high desert, the airliner boneyard at Mojave airport is visible from miles away,” writes aviation photographer Troy Paiva, who photographed airliners here in the 1990s and 2000s before security concerns made it a no-go area. “The long rows of faded tails seem to stretch to the horizon.”

The Royal Aeronautical Society’s Keith Hayward says aircraft are less of a headache to dismantle than other heavy transport. “I’m not sure how easy an aeroplane is to dismantle, but what goes together comes apart, and there’s a lot less heavy or dangerous materials associated with aircraft than ships.” But as less and less recyclable metal goes into making modern planes, the epic scale of the desert boneyards may be reduced. “In the future, the use of composites may make life more difficult to deal with final disposal, but there are industry protocols that are addressing the issue. But bone-yard parking will still be useful when demand fluctuates. Indeed, the numbers of parked airliners is often a good sign of slump or recovery, and is monitored by analysts.”

Back in Tucson, the long rows of planes at Davis-Monthan sit in the Arizona heat. For some, the sun-baked desert is a kind of aviation retirement home. For others, their flying days are not quite over.

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