Image credit: Forbes.com

From GlobalNews:

WASHINGTON — The Federal Aviation Administration (FAA) on Friday issued an emergency airworthiness directive for 2,000 U.S.-registered Boeing 737 NG and Classic aircraft that have been in storage, warning they could have corrosion that could lead to a dual-engine failure.

The directive covers planes not operated for seven or more consecutive days. The FAA issued the directive after inspectors found compromised air check valves when bringing aircraft out of storage.

From CNET.com:

Craig Barton may have the most difficult parking valet job in history.

As airlines around the world have grounded substantial numbers of their planes after the coronavirus pandemic decimated travel, the head of technical operations for American Airlines has spent the past two months trying to figure out where to park hundreds of planes. We're talking aircraft like the $375 million Boeing 777-300ER, a wide-body that's 242 feet long, with a wingspan of 212 feet.

"It's not the same as just putting your car in your garage and walking away for a month," Barton said. "There's not one place in the world where we could stick a few hundred airplanes." How to store hundreds of planes8:04 WATCH NOW

Since January, as COVID-19 has spread across the globe and governments have ordered stay-at-home lockdowns, people have stopped flying and bookings have vanished. By the second week in May, the Federal Aviation Administration was reporting that the number of commercial flights operating in the US, both domestic and international, had dropped 71% from the same period last year. Airlines, many of which had been on years-long aircraft buying sprees, suddenly found themselves with more planes than they needed. That left them with only one option: Keep the extra planes grounded until demand for air travel returns.

According to Cirium, a data and analytics firm that focuses on the travel industry, about 17,000 jets are now parked worldwide, representing about two-thirds of all commercial airliners.

It's not just a terrible financial prospect for an airline -- an airplane not carrying paying passengers is a depreciating asset -- it's also billions of dollars of highly sophisticated aircraft, all needing parking spots. And it's about more than just finding a place to wait out the pandemic, says Barton, who's responsible for overseeing American's fleet of 950 planes. Every airliner also needs constant attention so it's ready to return to the sky. "We have almost daily tasks that we have to do on each one," he said.

Looking for a parking space

What does a parking lot of planes look like? I went out to Oakland International Airport, across the bay from San Francisco, to see for myself.

Out in the distant reaches of the airport, far from the terminals where they might receive fresh loads of passengers, about a dozen Alaska Airlines Boeing 737s sat silently in the spot where they've been parked since March. Lit by a setting sun that gave their shiny white fuselages a warm glow, the planes rested close together near a disused hangar, the Eskimo face on every tail smiling over a chain-link fence into an empty employee car park. Further out, near the bay's shore, a dozen more 737s in the bright blue, red and yellow livery of Southwest Airlines also shimmered in the fading light.

It was clear none of these airliners were going to be taking off anytime soon. The wheels on the landing gear were secured with bright yellow chocks, and the engine intakes were covered by what looked like plastic wrap. Overhead, where normally a plane would be taking off every few minutes, the sky was eerily quiet. If the fur-hooded man whose face is the logo for the 88-year-old Alaska really knew what was going on, his broad smile surely would've faded.

See also: Flights are dirt-cheap. Should you book travel amid coronavirus?

The scene at Oakland is just a small slice of the new reality being played out around the world because of COVID-19. At major hubs like Dallas-Fort Worth and Hong Kong and at sprawling airports in the deserts of the southwest specifically designed for storing aircraft, commercial planes crowd aprons and taxiways, sometimes even spilling onto runways that've been closed to fit them. In some places, they're lined in neat rows. In others, they're packed in formations so tight they look like they'd need an army to untangle.

American, the largest airline in the world, is parking aircraft not just at its DFW home base, but also at airports in Tulsa, Oklahoma, and Pittsburgh, where it operates large maintenance bases, and at facilities in Mobile, Alabama; San Antonio; and Greensboro, North Carolina. Other airlines are also parking their planes in multiple locations, but with carriers everywhere the goal is to use whatever space is available. Teruel, Spain, is a popular choice for many European airlines, and faced with little room in the city-state of Singapore, the country's flagship carrier has flown its giant Airbus A380s to remote Alice Springs, Australia.

Though American had monitored possible effects from the coronavirus since the first reports of the pathogen began to surface, the plane-parking efforts didn't begin in earnest until the second week of March.

"It became clear that our flying operation was going to be much smaller than the number of aircraft that we have," Barton told me in a Zoom interview from American's headquarters in Fort Worth, Texas. "Everything has been changing so dynamically, even within a week."

Using its network operations team, American reduced its schedule from more than 3,300 flights per day at the end of February to less than 1,000 by May. The airline has now parked 460 aircraft, which represents almost half its fleet. And for some of the planes still in service, they might be "lazy flying," which means they make one or two trips a day, instead of a normal schedule of four or five.

This level of storing airplanes is unprecedented, said Barton, who recalls when American had to park some aircraft after the Sept. 11, 2001, terrorist attacks (when US airspace was closed for two days) and during the subsequent air travel slowdown. But the airline's effort over the last year to park its fleet of 24 Boeing 737 Max aircraft, which are still grounded worldwide following two crashes that killed 346 people, gave it a place to start.

"We had some experience over the past year in what it takes to keep aircraft down for extended periods of time," he said. "And that's honestly helped us."

Ready to fly

Most of American's parked aircraft are in an "active parked state," which means the airline can call them back into service at any time. Barton explains: "We know we're not gonna fly for a few days, but we still have to look after it."

These are typically newer aircraft, like American's Boeing 777s and 737s and its Airbus A319s, A320s and A321s (American is the largest operator of the narrow-body A321, which costs about $118 million). No matter how long an active parked state lasts, from a few days to several months, the process starts when a flight crew ferries the aircraft to its parking location. For two to three days after it arrives, mechanics walk around it to check the interior, pull off any catering, drain the water and seal up the engines, pitot tubes (small tubes near an aircraft's nose that measure airspeed) and any other access points to prevent animals and anything else from getting inside.

After that prep work is completed, the plane enters a short-term storage program where maintenance workers must perform set tasks every 10 days. The list includes running the engines (with the coverings off, of course), rotating the tires, running the Auxiliary Power Unit (these power an aircraft's electrical system when the engines aren't running), turning on the air conditioner, running the flaps systems to exercise the hydraulics, and either keeping the batteries charged or unhooking them completely. (Extra care is necessary on a Boeing 787 to keep its batteries from draining -- an expensive repair.)

And during this time, the plane's existing maintenance calendar doesn't stop, even when it's sitting on the ground. Much like a tune-up for your car, these routine checks keep an airplane in service for decades.

Every 30 days, an aircraft gets a little more care, but the schedule mostly repeats on the 10-day cycle. It's a lot of work, but Barton said the goal is to protect American's multimillion-dollar investment by making sure the aircraft still function. "Touching an aircraft every 10 days -- you have to put about eight hours of work into it every 10 days," he said. "So it's more or less a person a day per airplane we park to try to manage the storage program."

Reactivating a plane for service, which takes about three days, basically reverses the storage intake process. Mechanics take off the coverings; restore and purify the water systems; check the fuel tanks and lines to clear any algae; and finish any maintenance checks still on the aircraft's calendar.

"If you've stored it properly, you've validated throughout the whole process that the aircraft systems still work," Barton said. "So it's not like you're going out and hoping that the airplane will start back up."

Into retirement

If they expect that an airplane will be parked for a year or so, airlines prefer to store it in a desert location where drier air results in less corrosion. Barton says keeping an aircraft's cabin free of humidity is key. "[That way] it won't start to smell. That's what we worry about the most."

Long-term storage locations in the US include Pinal Airpark in Marana, Arizona; Southern California Logistics Airport in Victorville, California; and Roswell International Air Center in New Mexico. These are also aviation "boneyards," where airplanes long out of service waste away under the hot sun. All have arid climates and plenty of room to fit hundreds of aircraft (Roswell is more than 4,000 acres), from Boeing 747s to small regional jets.

Mark Bleth, the manager and deputy director in Roswell, said demand for space from airlines ramped up quickly in March. "We could see it was inevitable planes would be coming here, " he said. "We didn't know the scale of it, no one did."

By the first week of May, Roswell had taken about 300 aircraft, on top of 160 that were already there. The airport has room for about 300 more, but if new planes continue to arrive at their current pace of about five per day, Roswell will run out of room by the end of June.

The daily parking fee -- between $10 and $14, depending on the aircraft's size -- is cheaper than parking in downtown San Francisco. Much higher costs come from the necessary maintenance, which involves onsite MROs, or maintenance, repair and overhaul providers. Bleth estimates it takes about 200 hours to get an aircraft into long-term storage, plus the time needed to handle any regular checks after that. The tasks here are similar to those for a plane in active storage but include installing window coverings to protect cockpits and passenger cabins from the sun and paying extra attention to the engines so they don't corrode.

I talked to Bleth via Zoom as he stood on the edge of a taxiway under a bright blue sky. Behind him, a line of United Airlines Boeing 757s stretched far into the distance. It looks like the airport could span all the way to Texas, but Bleth said they still had to close a runway temporarily to store new arrivals and move aircraft already there to remote areas. "There was quite a bit of restructuring just to start intaking the planes," he said. "Now we're reshuffling again to optimize everything they have."

Most of the planes arriving at facilities like Roswell are those that airlines don't plan to use again. For American, that includes its Boeing 767s and 757s and the Embraer E190s and Airbus A330s it inherited from its 2014 acquisition of USAirways. Those aircraft were already on the books to be retired over the next couple of years, but the travel slowdown accelerated that schedule. (Roswell is also storing American's 737 Max fleet until the planes can be recertified by the FAA to carry passengers again).

Aircraft set for retirement face a variety of futures. They can be sold to other airlines, converted to freighters, an especially busy market right now, Bleth said. Or they may be scrapped completely for parts. American's McDonnell Douglas MD-80s, which retired to Roswell last year, will most likely meet the latter fate. But with air travel nowhere close to rebounding, Bleth expects a full house in New Mexico for a long time. "We're thinking this inventory will be here for a while, whether it's resold or it's still part of the airline."

Back to the skies

Barton doesn't know when air travel might return to "normal" -- the TSA is screening about 95% fewer passengers in May than the same month last year -- though he hopes July could show some improvement. When and if that point comes, American, like most other airlines, will have a leaner fleet, but the goal is to keep all parked aircraft feeling as if they've never stopped flying. As he put it, "the whole process is designed around ensuring that when the aircraft comes back into the operation it's as safe and reliable as it was when it entered into that storage program."

Barton said American is putting together what it believes to be the safest way to run an operation in the postcoronavirus world. Like all major US airlines, it's reducing onboard service, regularly "fogging" cabins with disinfectant between flights, limiting the number of seats sold and requiring the cabin crew and passengers to wear masks.

Like all other airlines, its aircraft also use High-Efficiency Particulate Air filters that completely change the cabin air every two minutes while filtering out 99% of viruses and bacteria.

The biggest question, of course, isn't just when passengers will feel safe traveling again. Rather, with large-scale events like conferences, festivals and sport tournaments canceled for the rest of the year, will there be anything to travel for? Ryan Ewing, an aviation journalist and founder of AirlineGeeks.com, said the industry's return will depend on when those business and leisure opportunities open up again.

"It's very bizarre and it's very bleak for the outlook in the long term," he said. "But it's hard to predict this kinda stuff, because you never know when people might want to fly again. ... People may be so tired of being in their houses, that they'll wanna get out and travel."