Aircraft Engine MRO Bottlenecks Raise Pressure on Aerospace Metals Supply

IATA

Aircraft engine MRO bottlenecks are becoming a structural challenge as durability problems, rapid fleet growth and shortages of spare parts increase maintenance demand across the global aviation sector.

Aircraft engine MRO bottlenecks have been intensified by problems affecting Pratt & Whitney geared turbofan engines and CFM International LEAP engines. Premature component failures are shortening time on wing and forcing additional shop visits alongside scheduled maintenance.

Aircraft engine MRO bottlenecks will become more significant as new-generation engine fleets expand. LEAP and GTF fleets are expected to increase by five to six times between 2024 and 2040 as airlines replace older narrowbody aircraft.

The resulting maintenance wave will also have important implications for nickel, cobalt, titanium and refractory metals used in high-temperature engine components.

LEAP and GTF Fleets Drive Long-Term Shop Visit Growth

Pratt & Whitney's GTF programme has faced major disruption from powdered metal defects affecting high-pressure turbine and compressor disks.

Groundings of GTF-powered aircraft peaked at 648 aircraft in March 2025, representing around 28% of the operating fleet, as engines waited for shop visits and replacement components.

CFM's LEAP engines have faced separate durability challenges, particularly involving stage-1 high-pressure turbine blades operating in hot and harsh environments.

These issues increase maintenance requirements before engines reach their originally expected overhaul intervals.

For mature engines, limited-life high-pressure parts typically require replacement after around 15,000-20,000 flight cycles, equivalent to roughly five to seven years of single-aisle aircraft operation.

Premature removals compress this cycle and increase demand for parts, skilled technicians and MRO capacity simultaneously.

By 2040, annual LEAP shop visits are expected to exceed 5,000, while GTF visits could surpass 2,000.

Engine manufacturers and MRO providers are adding capacity, but shortages of critical components are limiting how quickly maintenance throughput can increase.

MRO Growth Supports Superalloy and Titanium Demand

Rising engine maintenance creates an additional source of aerospace metals demand beyond new aircraft production.

High-pressure turbine and compressor components rely heavily on nickel-based superalloys because they must maintain strength at extreme temperatures.

Cobalt and refractory elements are also used in selected high-temperature alloys and coatings, while titanium is important in cooler engine sections where low weight and high strength are critical.

Higher shop visit volumes therefore increase demand for forgings, castings, disks, blades and replacement parts across the engine supply chain.

The pressure is not only on raw material availability. Qualified melting, forging, machining, coating and inspection capacity must also expand to convert specialty metals into certified engine components.

Spare parts access is becoming particularly important. Engine manufacturers, airlines and MRO providers will need longer-term supply agreements and greater production visibility to prevent maintenance queues from extending further.

The industry will also need to improve access to repair capacity and standardise best practices as the installed base of next-generation engines grows.

The Metalnomist Commentary

The engine MRO shortage is becoming a long-duration materials demand story rather than a temporary maintenance problem. As LEAP and GTF fleets multiply, qualified superalloy, titanium and engine-part capacity could become one of aerospace's most persistent bottlenecks.