Every American Airlines plane flies for hundreds of hours, carrying thousands of passengers for miles across the globe. But after a while, even the most reliable aircraft needs a break. For some of them, that break comes at a sprawling 3.3 million-square-foot facility in Tulsa, Oklahoma.
Functioning as its own ecosystem within Tulsa, this facility’s various hangars and warehouses are where the airline’s planes are picked apart. Seats and engines are refurbished. Exteriors are repainted to sport red, white and blue stripes along the tail fins.
These are only some of the many tasks that occur in this spacious, maze-like facility. Hangars upon hangars stretch across the massive property by a National Guard base and an Amazon warehouse.
Want more airline-specific news? Sign up for TPG’s free biweekly Aviation newsletter.
“It’s like a city within a city,” Barbara Cruz, a store supervisor at American’s Tulsa facility, said.
Thousands of American planes have gone through Tulsa since 1946, when the Fort Worth-based carrier relocated its maintenance base from LaGuardia Airport (LGA) to the old oil capital following World War II.
The base — a major hub for American’s maintenance operations — now has about 4,800 employees and claims to be one of the largest commercial aviation bases in the world.
At any given time, the facility can hold up to 20 narrow-body aircraft in its hangars; 800 commercial planes pass through it annually.
In 2020, American unveiled plans to invest $550 million in the Tulsa base to construct a new wide-body hangar and make improvements to each building in the facility. The new hangar should’ve begun taking shape in early 2021, but its construction start date was pushed back due to the coronavirus pandemic. It will be able to hold two wide-body (or about six narrow-body) aircraft at a time.
Reward your inbox with the TPG Daily newsletter
Join over 700,000 readers for breaking news, in-depth guides and exclusive deals from TPG’s experts.
Despite the renovation delays, the Tulsa base serves as an important destination for many American aircraft. It handles every bit of maintenance for a plane, from cleaning out toilets to inspecting engines.
Boeing 737s and 777s are the jets that primarily make their rounds in Tulsa. The aircraft either go through heavy, routine or unscheduled maintenance in a process that’s similar to surgery.
“We document all the findings,” Ed Sangricco, the managing director at the Tulsa base, said. “We go in, and we fix all those findings. We close the airplane, we put it back together again, and then we check everything — we make sure everything works.”
While the pandemic halted travel and grounded planes worldwide, that didn’t stop the maintenance technicians, engineers, managers and supervisors in Tulsa. American’s aircraft technicians were tasked with maintaining roughly 100 aircraft already at the base to prevent corrosion (and to stop weeds and birds from infesting the crevices of the planes). That meant remote work wasn’t an option for the employees at the Tulsa base.
Airlines received billions of dollars from the federal government during the pandemic partly to keep their fleets in tip-top shape, so they would be ready when travel demand returned.
“Maintenance requirements don’t stop during COVID-19,” Sangricco said.
What it takes to maintain a plane
Maintaining a commercial plane is a complicated process. Hearing all the steps to ensure an aircraft is running smoothly — all over the course of an eight-hour tour — was similar to taking a college crash course in physics and engineering.
Aircraft maintenance is heavily governed by the Federal Aviation Administration, which has a set list of requirements and deadlines for every plane component. Every record chronicling the maintenance of an aircraft needs to be preserved to be in compliance with the FAA, according to Roger Steele, a supervisor at the Tulsa facility who specializes in 737 narrow-body maintenance.
So, document holders containing slips of paper that detail every task from the FAA line two walls of an office within a 737 hangar at the Tulsa base.
At the start of a visit, a 737 narrow-body will undergo about 1,200 required tasks — excluding non-routine inspections — before it can fly again.
The Tulsa facility is never quiet. Throughout my tour of the maintenance site, I could hear constant drilling noises and the occasional thunderous engines of a National Guard plane taking off a couple of miles away as Steele explained the ins and outs of narrow-body maintenance.
The 737 I saw in the hangar had already been stripped down, as it was in its fifth day of maintenance. (The crew at American has around 25 days to completely finish work on the plane.)
The seats, the walls and the flooring were completely gutted from the aircraft. All that was left inside were gray insulation bags on all sides, which made the 737 look more like a cave than a plane.
Inside, technicians were already hard at work. One was by the plane’s back door, critically documenting what parts had been affected by corrosion.
While several areas can suffer from corrosion, a plane’s galleys and lavatories are the most susceptible to corrosion and environmental damage, as moisture from toilets and soft drinks wear down the interior.
“What coffee and soda pop can do to an aircraft after humans consume it is very corrosive,” Steele joked.
Once the technician documented the damage, the next step was determining what parts needed reinforcement. One piece of metal in the galley suffered from corrosion, so the technician sanded the area and recorded its remaining structural thickness.
Like the maintenance process itself, refurbishing an aircraft is anything but glamorous. At the Tulsa base, the majority of hangars and buildings have no air conditioning, leaving most of the workers stuck toying away at engines and aircraft in the sweltering summer heat.
When I toured the site, it was already a muggy 90 degrees, but Tulsa summers can soar well into the 100s during the season’s peak.
For some, the day starts early. Robert Bales, a maintenance technician who works on wide-body half galleys, normally wakes up at 5 a.m. for his 6:30 a.m. shift.
Each technician works around 8 1/2 hours. Much of the schedule, specifically for cabin work, is determined by the crew chief and the needs of the aircraft.
Before someone can start working at the facility as a technician, they must undergo significant training.
Gabriel Figueroa Navedo, another wide-body aircraft technician, said he went to trade school to receive an FAA-issued aircraft technician license. There, Navedo — who first started his career managing reservations and bookings for American — learned extensively about topics like hydraulics and electricity.
However, Navedo said many of those skills do not directly apply to his day-to-day job. Instead, the training provided a general knowledge of planes.
“I like to call it a license to learn,” Navedo said, “because it’s got to cover stuff like small propeller engines, and the FAA doesn’t know if you’re gonna work here, or if you’re gonna be working on your own private plane.”
Even the seats and toilets need a makeover
When an aircraft’s seats need refreshing, the plane goes to a different warehouse, where the seats get disassembled. During this process, technicians tend to find all sorts of trash underneath, including gum, candy, pills, credit cards, cellphones and iPads.
“You’re gonna find no telling what,” Brent Strickland, a supervisor who primarily works on Boeing 777s and 787s, said.
Strickland said he has even found false teeth and engagement rings inside the seats.
After removing the various items passengers leave behind, the seats are washed and left to dry. Then, the technicians check the hardware for any damage.
Cushions are changed about every six years, according to Strickland, and it only takes two to three days to completely finish a seat.
It’s not just the seats that need refurbishing during maintenance — the toilets also get picked apart. The waste tanks are cleaned out, and the flushes are inspected by another team of technicians dedicated to toilet maintenance. Strickland described those team members as “another one of those unsung heroes.”
Dee West, a technician, cleaned out a water valve during my tour, closely inspecting the valve under the scope of a flashlight before carefully reassembling the three parts and a spring in the pipe.
“It ain’t no joke,” he said. “It’s gotta be done right.”
One mistake by a toilet technician could be costly for the airline, as each toilet costs $17,000.
Perhaps surprisingly, this area of focus is one of the more desirable on the Tulsa base, according to an American spokesperson. That’s because it’s one of the few jobs workers can do inside an air-conditioned building — providing a reprieve from the otherwise hot and muggy weather Tulsa experiences every summer.
Engines, windows and other plane parts also get a makeover, depending on the aircraft’s maintenance schedule. This includes the fans and combustive parts of the engine, which the staff works on separately in “cold” and “hot” rooms within another hangar, respectively.
Blue lines on the walls demarcate the “cold” parts of the room, whereas painted yellow lines indicate the “hot” area.
Staff members also inspect some parts of the engine by soaking them in a fluorescent lime-green liquid to magnify which parts need to be reinforced.
Whenever parts like the wings and the radome — located at the tip of the plane — need a lift, they are sent to a composite center. There, they get reinforced with materials such as carbon fiber and a honeycomb web made from materials like aluminum.
“[It’s] poetry in motion,” Jody King, a composite repair center crew chief at American’s composite repair center, said when referring to the process of fitting the materials onto parts of the aircraft.
The reason this complex web of maintenance is even possible is because American’s site also has a warehouse containing thousands of parts and stickers. These parts are either shipped to other hangars in Tulsa or to airports and third-party services that need to do maintenance on an aircraft.
Gearing up to fly again
Before a plane is ready to fly again, the landing gear — the wheels on the plane, in layman’s terms — must be checked, and the exterior must be repainted and rewaxed.
You may not notice the gargantuan size of planes since you typically only see them from afar in the sky or through the windows of an airport. However, were you to see one up close, you’d be struck by the size.
The landing gear alone measures at least 21 feet tall, roughly the equivalent of four people my height (I’m around 5 feet, 4 inches) standing on top of one another.
The wings also feel so vast it almost seems impossible that workers can repaint them by hand in a matter of days; the team uses foam rollers and brushes, according to Jeff Green, a shared services supervisor.
Once the plane completes its maintenance maze in Tulsa, it’s ready to return to the skies and fly to hundreds of destinations. Later, it’ll likely touch down in Tulsa yet again to go through the same routine.