This year was supposed to herald air travel’s big comeback, with China reopening, airlines ramping up flight schedules and airports going on a hiring spree to handle the surge.

But a potential bottleneck to that growth is looming in form of a shortage of aircraft engines and spare parts, particularly on workhorse Airbus SE and Boeing Co. jets. The shortfall is being exacerbated by the fact that more carriers are flying with the latest-generation turbines that — while as much as 20% more fuel efficient — also have been prone to far more frequent maintenance cycles than their more robust predecessors.

As a result, airlines around the world have been forced to ground hundreds of airplanes just as they gear up for what stands to be a busy summer travel season. Air Baltic Corp AS says 10 of its 39 Airbus A220s are currently out of service due to engine issues. In the U.S., budget carrier Spirit Airlines Inc. warned it would scale back growth plans due in part to a spate of malfunctioning engines. And India’s IndiGo is seeking compensation for about 30 planes it has had to ground due to parts shortages, some of which are tied to engines.

Supply-chain constraints were rippling through the industry even before the pandemic, and in its aftermath engine makers have struggled with a lack of skilled mechanics and component shortages.

The latest engines from Raytheon Technologies Corp. and a General Electric Co.-Safran SA venture feature exotic metal alloys, coatings and composites needed for them to operate at furnace-like temperatures. Airlines say turbine components are wearing more quickly and being sent to the shop earlier than initially expected.

Running Hot

AirBaltic, Spirit and IndiGo have planes equipped with engines made by Raytheon’s Pratt & Whitney division. Another Indian discount carrier, Go First, is seeking compensation from Pratt for 24 aircraft that it has been forced to ground, according to a person familiar with the matter.

“The engines are running hotter, and the materials used for that are not withstanding the pressure, so there are more engine-related problems than we used to face previously,” said Qatar Airways Chief Executive Officer Akbar Al Baker.

Turnaround times for engine repairs have tripled as waits for certain parts drag on for more than a year in some instances. Supplies of engine components are further stretched as Airbus and Boeing clamor for higher output of new engines, as they strive to pump out their best-selling single-aisle aircraft models in record numbers.
“Right now that’s hotter than hell,” Cliff Collier, a Texas-based aviation consultant, said of the engine sector.

“There are parts shortages left and right and it’s impacting MROs badly,” he said referring to maintenance and repair organizations.

GE Chief Executive Officer Larry Culp and other executives laid out the company’s future as a standalone aerospace manufacturer at an event on March 9. Executives spoke about actions taken to improve the durability of the Leap turbine made by the venture, called CFM International, for Airbus’s A320neo aircraft family and Boeing’s 737 Max.

“Durability is our No. 1 priority,” Russell Stokes, CEO of commercial engines and services at GE Aerospace, said of the Leap at the investor conference. “We want that engine on wing making money for our customers, exactly where it belongs.”

The Leap engine’s time-on-wing is better than that of its predecessor, the CFM56, at the same point in its service life, about six years after its first commercial flight, according to Mohamed Ali, vice-president for engineering at GE Aerospace, while acknowledging that the engine’s removal rate and maintenance needs are falling short of customer expectations.

Closing the Gap

The turbofan models by Raytheon’s Pratt & Whitney division are flying an average of about 10,000 hours before they need to be removed for overhauls. That’s only about half the so-called time-on-wing of its predecessor engine, despite multiple fixes and upgrades to boost longevity, Raytheon CEO, Greg Hayes, said at a Barclays conference in February. Closing that gap will be a challenge over the next five years, he said.

Around 370 Airbus A320neos and A220s, along with 737 Boeing Max jets, are currently classified as stored, according to data from Cirium. The aviation data and analytics company defines such aircraft as those that are idled for 30 days or more for any of a variety of reasons.

Airbus said it’s closely monitoring the performance of engines on its aircraft. Boeing had no immediate comment.

Many airlines keep a cache of spares on hand, but there simply aren’t enough replacement engines available to keep pace with repairs. Carriers may be forced to keep older craft longer than anticipated and fly each plane more hours per day. In a pinch, they might even bring planes out of their pilot training fleets and put them into regular flight service. The shortage could crimp industry plans to expand the number of flights offered in 2024 and beyond.

Production Target Risk

Airbus and Boeing are counting on rising output of turbines to keep their A320 and Max assembly lines humming. The glut of engine repairs looks likely to extend into 2024 or even 2025, raising the risk of too few power plants to meet plane-maker production targets, said Paul Dolan, CEO of Aviation Technical Services, a large U.S. maintenance provider.

Introduced a little over a decade ago, the new engine options for the A320 family and the 737 helped spur an unprecedented surge in demand. Fuel is often among the single largest expenses for airlines, so any reduction in consumption instantly feeds through the bottom line.

Pratt’s powerplant, which is used on models including Airbus SE’s best-selling A320neo family and the smaller A220, as well as Embraer SA’s E2 regional jet, struggled with teething pains after it was introduced, with multiple carriers reporting inflight shutdowns. Pratt subsequently said it had resolved the issues, but some carriers say they continue to struggle.

The Pratt engine “has experienced diminished service availability, an issue that has been steadily increasing” since mid-2022, Spirit CEO Ted Christie said on an earnings call February 7.  “This is not just a Spirit issue.”
Some A320neos have had engines removed after just 2,000 to 3,000 hours in operation, while A220s have had engines come off after only 1,000 hours, according to Doug Harned, an aerospace analyst with Bernstein. Go First’s A320neos have had engines fail at 4,900 hours, the person familiar with the matter said. The carrier has had 41% of its fleet grounded, and was forced to seek a $525 million over the past two years from its parent in order to stay afloat, the person said.

Harned calculated that 18% of A220s and 13% of A320neos powered by these engines were out of service as of early March. CFM’s Leap has performed better, although 4% of A320s and 5% of Max jets are grounded — much to the consternation of customers, he wrote in a March 2 report.

A Raytheon spokesperson disputed those estimates for the Pratt-powered planes, saying less than 10% of those jets are parked. The company declined to comment further on the issues, including Go First’s grounded planes.

Frequent Shop Visits

The GE-Safran Leap model also has faced issues. A build-up of carbon around the fuel nozzle has resulted in inspections after 1,000 hours of flight, Harned said. The engine’s high-pressure turbine shroud has been redesigned over the last few years “but is still leading to a degradation in engine performance” and consequently more frequent shop visits, he said.

CFM said it introduced a new configuration of the high-pressure turbine shroud that went into production in 2019 and is retrofitting the remainder of the Leap engine fleet with the change.

Once engines are opened up for repairs, airlines face another costly hassle: Long waits for spare parts.

“What we’re seeing is basically a queue building up due to insufficient maintenance capacity,” said Andy Cronin, the chief executive officer of Avolon Holdings, a major aircraft lessor. “It was simply never intended that the engines would need this much maintenance at this stage in the program.”