Airlines are gradually bringing aircraft affected by the years-long engine crisis back into service, but the financial impact of the disruptions is proving more difficult to reverse.
Air New Zealand illustrates how the costs can persist even as fleet availability improves. Engine problems at one stage left up to 20% of the airline’s fleet unavailable, prompting it to lease additional aircraft and engines to maintain its schedule.
Although availability has improved significantly, Chief Executive Nikhil Ravishankar told Reuters that it could take another 12 to 18 months to unwind the additional leases and associated expenses. Supplier compensation is expected to offset only part of those costs.
The disruption was driven by durability issues affecting some newer-generation engines and a powder-metal problem at Pratt & Whitney that led to accelerated inspections and engine removals. Labor shortages, limited parts availability and constrained repair capacity further complicated the situation.
To keep aircraft flying, airlines turned to leased engines and replacement aircraft. As a result, they have continued to face elevated leasing, parts and overhaul expenses even as the number of grounded aircraft declines.
Aircraft delivery delays from Boeing and Airbus have added another layer of pressure. With new jets arriving later than planned, airlines are keeping older aircraft in operation for longer and in some cases carrying out engine maintenance that had previously been expected to be avoided.
A Reuters analysis of U.S. Transportation Department data found that six major U.S. airline operations reported spending roughly 68% more on engine labor, aircraft-engine repairs and engine materials in 2025 than in 2019. Over the same period, their flight hours increased by about 10%.
The latest available data showed the trend continuing. Spending in the three categories rose 17% year-on-year in the first quarter, while flight hours increased by less than 2%. Maintenance costs can vary depending on engine age, accumulated flight cycles, fleet-management decisions and the timing of shop visits, when engines are removed for inspection or repair.
The Transportation Department figures do not specify the reasons behind the increase. GE Aerospace, Safran and RTX did not respond to requests for comment, while Rolls-Royce declined to comment.
Pratt & Whitney’s geared-turbofan engines demonstrate the disparity between falling groundings and rising maintenance demands. Aircraft grounded because of issues involving the engines fell 25% in the first half of the year. However, the share of heavier PW1100G repair work in the second quarter was 14 percentage points higher than a year earlier.
Recent regulatory filings from United Airlines and American Airlines also showed higher maintenance expenses during the first half, with engine overhaul work contributing to the increase.
Parts and materials typically represent about 60% of the direct cost of an overhaul for a single-aisle aircraft engine, according to consultancy Oliver Wyman. While newer engines provide fuel-efficiency benefits, their maintenance can be more expensive because repair networks are less developed and supplies of used components remain limited, said Sam Sargent, a partner at the consultancy.
George Dimitroff, head of valuations at Ascend by Cirium, said overhaul and mandatory parts-replacement costs for newer LEAP and GTF engines have increased by roughly twice as much since 2019 as costs for older CFM56 and V2500 engines. LEAP and GTF engines power most aircraft in the Airbus A320neo and Boeing 737 MAX families.
Not all of the increase in maintenance spending is attributable to technical problems. As newer fleets mature, they naturally require more scheduled maintenance.
Leases Continue After Groundings End
Long engine shop visits are forcing airlines to rely on replacement engines for extended periods.
JetBlue Airways has said some Pratt & Whitney engines can require between 200 and 300 days to complete a shop visit. The airline has consequently increased its use of leased engines.
Transactions completed over the past year show short-term lease rates for some newer LEAP and PW1100G engines exceeding $6,500 per day, compared with about $5,000 per day in 2022-23, according to aviation consultancy IBA.
Austin Willis, chief executive of engine lessor Willis Lease Finance, told Reuters that airlines seeking replacement engines have frequently opted for leases of around three years, while shorter agreements are often extended. This can leave carriers paying lease costs even after their own engines have returned to service.
Older Aircraft Bring Higher Maintenance Bills
Keeping older aircraft in service also comes with significant costs. A complete overhaul of a CFM56-5B engine used on older Airbus A320-family aircraft can easily exceed $10 million, Willis said.
Oliver Wyman and the International Air Transport Association estimate that delayed aircraft replacements may have added around $3.1 billion to global airline maintenance costs in 2025.
Longer aircraft lifespans are also reducing the supply of cheaper used engine components. Industry officials and experts say fewer engines are being dismantled for spare parts, increasing prices for used components and making airlines more reliant on newly manufactured parts.
Airlines and Engine Makers Clash Over Costs
The rising maintenance burden has intensified disagreements between airlines and engine manufacturers over repair prices and pricing power.
At the International Air Transport Association’s annual meeting in June, United Airlines Chief Executive Scott Kirby was asked whether engine manufacturers had excessive pricing power and were using supply shortages to charge airlines more. His response was: “Yes and yes.”
Engine manufacturers argue that developing new technologies requires billions of dollars of investment and that engines are often sold at significant discounts initially, with manufacturers expecting to recover those costs through parts and maintenance over the life of the product.
Safran Chief Executive Olivier Andriès said last month that increases in repair and spare-parts prices should remain moderate and reflect higher supplier costs rather than an “abusive posture.”
GE Aerospace Chief Executive Larry Culp said last month that aircraft groundings related to LEAP engines had fallen to near zero. The company is also introducing upgraded components intended to extend the period engines can remain in service before major maintenance is required.
RTX said it is working to improve engine durability and expand repair capacity. The company reported that Pratt & Whitney’s PW1100G repair output increased 43% in the second quarter from a year earlier, while turnaround times fell 23%.
For airlines, however, the financial burden is not disappearing as quickly as grounded aircraft.
“The fact that AOGs (aircraft on ground) have come down, that doesn't change the maintenance cost,” Willis said.
Source: Reuters News