See inside one of the world's largest aircraft 'boneyards' where planes go after airlines are done using them

An aircraft in reclamation at the Pinal Air Park in Marana, Arizona.Taylor Rains/Insider

• Pinal Air Park in Arizona is one of the largest aircraft storage facilities in the world.
• The multi-million business boomed during the pandemic as airlines worldwide grounded hundreds of jets.

Airlines were forced to make drastic changes in 2020, including furloughing pilots, cutting routes, and indefinitely storing hundreds of planes in the desert.

Sergio Perez/Reuters

One of these facilities is Pinal Air Park in Marana, Arizona — a small town located about 90 miles southeast of Phoenix.

The dry clime is favorable for preventing corrosion.      Christian Petersen/Getty

As airlines started to shrink in 2020, hundreds of planes from all over the world flew to the 2,080-acre airpark.

Pinal Airpark in Marana, Arizona.      Ramon Purcell/Boneyard Safari

With the influx, Pinal had to take special precautions to ensure the aircraft were ready to fly once travel eventually rebounded.

Pinal Airpark in Marana, Arizona.      Taylor Rains/Insider

Because of this, Ascent Aviation Services — the largest aircraft service provider on the airfield — had to beef up its staff to maintain the constant arrivals.

A maintenance hangar at Pinal Airpark in Arizona.      Thomas Pallini/Insider

Company CCO Scott Butler told Insider that starting in March 2020, planes were coming in at about one per hour — requiring over 150 extra mechanics.

Pinal Airpark in Marana, Arizona.      Thomas Pallini/Insider

Additional parking lots were built to handle the hundreds of planes, which continued to be filled into 2021 with jets coming from places like the US, South Korea, UK, Australia, and Canada.

An aircraft in reclamation Pinal Airpark in Marana, Arizona.      Thomas Pallini/Insider

I went inside one of the US' largest aircraft storage facilities and saw how it isn't emptying out despite the rise in air travel

Leasing companies were also filling the airfield after buying up inexpensive planes sold during COVID and storing them at Pinal.

Lessors did not have much business in maintenance prior to the pandemic as they typically left that task to the operator. But, Butler explained the companies started being more hands-on with AAS because the jets had to get upkeep during storage.      Taylor Rains/Insider

Inside a remote Arizona aircraft boneyard storing nearly 300 planes grounded by the pandemic

However, with travel now roaring back and demand on track to surpass 2019 levels, AAS has gotten back to its roots — maintenance, repair, and overhaul (MRO).

Before the pandemic, MRO services made up over 70% of the company's revenue.      Thomas Pallini/Insider

Basic offerings include simple maintenance checks and on-demand repairs, like fixing the landing gear or inspecting the flight controls.

AAS has its own landing gear shop to repair and overhaul parts to reuse on other planes.      Taylor Rains/Insider

However, heavy maintenance is the most costly for airlines. This involves a full assessment of the aircraft and can take up to 60 days for widebody jets, Butler explained.

For example, less invasive maintenance checks ("A") will inspect the engines and their fan blades. Heavy maintenance checks ("C" and "D") will actually remove those components for inspections.      Taylor Rains/Insider

"A narrowbody will cost around $2 million," he told Insider. "With widebodies, you're easily looking at $3 million."

A view of the wires and systems inside an aircraft a Pinal Airpark.      Thomas Pallini/Insider

And, these projects take a lot of manpower. Butler said the company targets 400-500 hours per day for widebodies and 300 per day for narrowbodies.

There could be anywhere from 25 to 40 people working on an aircraft at once.      Thomas Pallini/Insider

Because these checks are so expensive, many carriers opt to sell the aircraft when it gets to that stage in its lifecycle, which is typically every six to 10 years.

A narrowbody jetliner at Pinal Airpark in Arizona.      Taylor Rains/Insider

Source: National Aviation Academy

Or, the operator will allow an aircraft lease to expire. This means if the lessor finds a new home for the plane, it will need to be fitted for its next contract.

For example, Alaska recently announced it would break the lease of its last A321neos and expects to hand them off by the end of Q2 2023. If and when this happens, the new owner will need the re-paint and likely retrofit the cabin.      Thomas Pallini/Insider

For these conversions, AAS offers additional services, like re-painting liveries, switching out flight systems, and installing new cabins.

An aircraft going through AAS' re-painting process at Pinal Airport in Arizona.      Taylor Rains/Insider

Sometimes, aircraft will transition from a passenger jet to a cargo plane — a service the company saw increased popularity during the pandemic, especially with older jets.

Amazon has tapped Hawaiian Airlines to fly A330-300P2F (pictured) converted jets for its lucrative air cargo business.      EFW

See the giant Airbus A330 freighter aircraft that will power a new lucrative cargo operation for Amazon

For flight tests and deliveries, the operator will arrange pilots, who will land and depart on the designated runway stretching Pinal's airfield.

The runway at Pinal Air Park.      Ramon Purcell/Boneyard Safari

Overall, Butler said AAS can do nearly anything an airline would need from an MRO standpoint.

An employee working inside a conversion aircraft at Pinal Airpark.      Taylor Rains/Insider

The main service it can't provide is engine overhauls, which are outsourced to other shops.

The engine detached from an aircraft at Pinal Airpark in Arizona.      Taylor Rains/Insider

"A lot of our current projects are just waiting on engines," Butler told Insider. "There's a backlog because no one did engine maintenance during COVID because of the expenses."

A covered engine inside a hangar at Pinal Airpark.      Taylor Rains/Insider

He explained this is adding to the already strained supply chain that has caused a slowdown in returning aircraft to service.

An aircraft being overhauled at Pinal Airpark.      Taylor Rains/Insider

While AAS does a lot of work keeping airplanes flying, it also offers aircraft reclamation and end-of-life services.

An aircraft in reclamation.      Taylor Rains/Insider

This involves disassembling and disposing of unwanted parts, which make up about 10% of the airplane.

Ascent Aviation Services breaking down aircraft.      Ascent Aviation Services

According to Butler, the other 90% is recyclable. These include things like engines and galley carts...

An aircraft in reclamation.      Taylor Rains/Insider

...and avionics and landing gear.

Pinal Airpark in Marana, Arizona.      Thomas Pallini/Insider

However, he said custom interiors do not have much value except to the original operator.

The interior of an aircraft in reclamation.      Thomas Pallini/Insider

A plane can spend months being salvaged, with hundreds of collected parts being resold or repaired for future use.

An aircraft in reclamation.      Ascent Aviation Services

The re-certified pieces can be sent back to airlines who keep them in their inventory as spare parts — meaning retired jets can still provide for current ones.

Two aircraft in reclamation with their landing gear already salvaged.      Taylor Rains/Insider

Inside a remote Arizona aircraft boneyard storing nearly 300 planes grounded by the pandemic

Meanwhile, some carriers will take parts of the metal to create memorabilia, like cutting the logo or airline name from the fuselage and using it as wall art.

An AAS spokesperson told Insider this was the logo of a company that an individual wanted as a keepsake.      Taylor Rains/Insider

In addition to the strong MRO and reclamation divisions, storage and parking is still a strong revenue source for AAS.

Aircraft in storage.      Taylor Rains/Insider

"80% of all the stored aircraft worldwide are stored in the Southwest," Butler told Insider in 2021.

One of the 747SPs at Pinal Airpark in Arizona.      Taylor Rains/Insider

During an April 2023 tour of the airpark, Insider found the main lot full of planes, including two rare Boeing 747SPs.

One of the Boeing 747SPs at Pinal Airpark.      Taylor Rains/Insider

Mechanics spend up to two weeks getting a plane ready for storage. Important components like the engines, pitot tubes, systems, and landing gear are sealed and protected.

An aircraft with its external systems covered.      Taylor Rains/Insider

This is especially important to prevent critters and other wildlife from taking up residence in the airplane's openings and small crevices.

Pinal Airpark in Marana, Arizona.      Thomas Pallini/Insider

Butler told Insider the stored aircraft also get regular maintenance checks to keep them airworthy.

A Boeing 777 undergoing maintenance.      Taylor Rains/Insider

Parked planes, on the other hand, do not get this service and can be left to collect dust — giving Pinal its "boneyard" nickname.

An old Boeing 747 that has been sitting at the airpark for years.      Taylor Rains/Insider