The world’s largest commercial passenger jet, the Airbus SE A380, enjoyed an unexpected resurgence hauling full loads of passengers when global travel rebounded after the pandemic. But keeping the aging superjumbo safely airborne is becoming an increasingly expensive headache for airlines.

Two decades after its maiden flight, regulatory bulletins ordering repairs, inspections or replacement parts for the massive four-engined plane are piling up. While some are procedural, such as a demand for timely equipment checks, others are more serious.

Leaking escape slides, cracked seals and a ruptured landing-gear axle feature among 95 airworthiness directives for the A380 listed by the European Union Aviation Safety Agency (EASA) since January 2020.

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That’s about double the number of directives for large Boeing Co aircraft in the same period.

With newer, more fuel-efficient jets in short supply, airlines committed to the twin-deck A380 have little choice but to keep flying it. In its youth, the A380 was a triumph of international collaboration, with 4 million parts made by 1,500 companies worldwide. Now, in old age, the aircraft’s complexity is testing aviation’s fractured supply chains in the post-COVID era.

“The A380 is a complex aeroplane whose scale does make it more demanding to maintain compared to other aircraft,” the European Union Aviation Safety Agency said in a statement. “It is very important for safety that there is no stigma attached to publishing an airworthiness directive -– safety must come first.”

The agency said such directives, which mandate actions to make an aircraft safe, “can vary hugely in scope and urgency.” The volume of airworthiness directives for different planes “is not a good basis for comparison,” EASA said.

Stranded passengers

However, with the capacity to carry 485 passengers or more, delays caused by mechanical failures can be costly and create a cascade of scheduling headaches. A Qantas Airways Ltd A380 on the flagship Sydney-London route broke down in Singapore on May 7 with fuel-pump problems. The onward flight to London was pushed back more than 24 hours and passengers accommodated in hotels.

That was at least the second fuel-pump issue to delay QF1 in Singapore since Qantas reactivated its A380s. More recently, Qantas passengers who were due to depart Singapore on July 14 for Sydney on an A380 were delayed for days because of technical difficulties. Plans to retrieve them sooner were complicated by damage to another A380 at Sydney airport, when an aerobridge slammed into one of the engines.

A British Airways A380, G-XLEB, recently spent more than 100 days in Manila. After returning to London Heathrow in mid-June, it flew just seven days of the next 30, according to Flightradar24. Still, IAG SA-owned British Airways from next year will embark on an interior upgrade program, including overhauling A380 cabins, suggesting the airline will keep flying the plane for years.

For airlines using the A380, large-capacity alternatives are scarce. Boeing’s new 777X is years behind schedule and Airbus can’t make long-haul A350s fast enough. Meanwhile, A380 operators are left with an out-of-production superjumbo that will only become more needy and more expensive to run. In online aviation forums, some services are gaining a name for breakdowns, cancellations or overnight delays.

In a statement, Airbus said the A380 “continues to operate scheduled services with a high level of operational reliability, standing at 99 percent for the global fleet over the past 12 months. Airbus is committed to providing full technical support to customers to ensure that they can optimize operations with their A380 fleets, and this will continue as long as the aircraft remains in service.”

60,000 hours

Meanwhile, A380s are taking up space and manpower in workshops around the world, exacerbating a shortage of repair facilities for the wider commercial fleet. A comprehensive check of the massive plane can consume 60,000 hours of labor, according to aircraft repairer Lufthansa Technik.

Qantas is sending some double-deckers to Dresden in Germany to be overhauled; British Airways flies its to Manila for repairs; and Emirates, the world’s biggest operator of A380s, maintains some in China.

Some of the aircraft’s recent faults stem from prolonged periods on the ground during the pandemic, when airlines parked their A380s in the Californian desert, central Spain or the Australian outback.

An airworthiness directive from the European Union Aviation Safety Agency on May 16 ordered emergency inflatable escape slides to be replaced. Glued seams had split, probably due to exposure to moisture and heat during storage. The fault could have fatal consequences, EASA said.

On April 7, EASA ordered inspections on A380s after cracked sealant was found on fittings attaching the landing gear to the wings. A directive in April last year required some landing gear axles to be replaced after a rupture on a plane that had been in storage since 2020.

The future of the A380 was already in doubt when COVID-19 halted global travel in early 2020. The year before, Airbus had killed off production after underwhelming sales.

When COVID-19 receded and borders reopened, the A380 suddenly found new purpose. Travel boomed and carriers including Singapore Airlines Ltd, Deutsche Lufthansa AG and Qantas once again embraced the plane’s unrivaled carrying power.

In a statement, British Airways called the A380 “a vital part of our long-haul fleet. Through working closely with Airbus, we’ve seen consistent year-on-year improvements in its reliability.”

Qantas said the plane “is a key part of our international network, and we’ll continue to fly them for years to come. All Qantas A380s have gone through a scheduled major maintenance overhaul in recent years, as well as significant upgrades to the cabin interiors.”

Other A380 operators were reluctant to provide specific details. Asiana Airlines Inc said “issues related to aircraft operations and maintenance are difficult to disclose externally.” Korean Air Lines Co said it “maintains its A380 fleet to the highest safety standards, in strict accordance with all regulatory requirements and manufacturer guidelines.”

Singapore Airlines said its 12 A380s are important to operations but it was “unable to comment on specifics.” The company said it works closely with “Airbus and our suppliers to ensure the ongoing reliability and serviceability of our A380 fleet.”

To be sure, the A380 still has fans. Emirates, which has cannibalized some A380s for spare parts, plans to keep flying the aircraft until the end of next decade. The airline’s president, Tim Clark, has likened the jet to a huge vacuum cleaner capable of gobbling up passengers like no other plane.

READ MORE: Qantas plane damaged in collision with aerobridge at Sydney Airport

Reliability issues are the latest twist for a superjumbo that has almost always been divisive. Passengers still love the A380’s cavernous interiors and audacious scale. Airlines wrestle with its logistics needs — from longer runways to extra-large hangars — as well as the mechanical dramas.

Supply chain constraints have increased the price of parts, servicing and engine repairs on all major aircraft, said Eddy Pieniazek, Ishka’s head of advisory.

“With the A380 being of its size and having four engines, this escalation in maintenance costs has become even more noticeable,” said Pieniazek.