Demand Is Soaring For Commercial Engine Maintenance, Repair Slots

Aircraft engine maintenance, repair and overhaul (MRO) has become a choke point for commercial aviation. 

Repair shops are struggling to service a growing number of aging narrowbody engines as airlines seek to extend their lives. Increasing the strain, many new-generation engines are coming in for their first visits.

The combined surge in demand has left airlines facing historically high shop turnaround times (TAT), up by 35% or more for legacy engines and more than 150% for new-generation engines compared to pre-pandemic levels. In addition, the wait times just to secure an MRO slot rose by two to three months and, in some cases, six months. These uncommonly long delays to maintain and repair engines have reduced the availability of airline fleets.

While the industry has made some headway in restoring parts, labor and facility capacity that was cut at the outset of the pandemic in 2020, Bain analysis shows engine MRO demand is likely to experience a near-term peak in 2026 and remain constrained through the end of the decade. The capacity shortage presents a challenge but also an opportunity for MROs and suppliers. Companies that invest today will be best positioned to capture a larger slice of the market and propel long-term growth.

A combination of factors has created a near-perfect storm for engine services. Shop visits deferred during the pandemic led to significant pent-up demand. At the same time, newer-generation CFM International Leap engines and Pratt & Whitney GTF engines are requiring repairs in much greater numbers than anticipated due to an array of issues.

Compounding these delays, OEMs have struggled to ramp up production of new-generation aircraft due to supply chain constraints and quality setbacks. Deferred deliveries mean airlines must continue to rely on aging fleets. Many of these engines would already have been scrapped for parts, but instead are still in use and returning to MRO shops in growing numbers. And servicing aging engines often involves greater complexity and longer TATs.

A lack of spare parts is also contributing to longer shop visits. Demand for OEM parts is outpacing supply by 10% to 20%. Labor shortages are adding to maintenance delays, with MRO shops struggling to recruit and retain technicians. Additionally, OEMs have not issued enough repair licenses to meet demand, limiting the supply of repaired parts.

Lasting Impacts

Even as MRO shops scramble to meet near-term demand, the capacity shortage is likely to persist, given the generational shift in airline fleets. Although legacy engine shop visits are at peak levels, another large surge in demand from new-generation engines will begin toward the end of the decade.

The decision by many airlines to delay the retirement of legacy aircraft amid uncertainty about new OEM deliveries has limited the supply of used parts. Used serviceable material (USM) plays a critical role in providing operators with a cost-effective, low-risk option to access life-limited parts. For some MRO shops, USM parts cover as much as 30% of total part demand. In particular, airlines have put off the retirement of Boeing 737NG aircraft and Airbus A320ceo models. That trend is likely to continue for several years, given insufficient deliveries of new aircraft.

Eventually, the volume of parts from teardowns will rise—however, the parts from engines retiring in the latter half of this decade will have a shorter remaining life than typical teardowns due to aggressive engine rotation practices during the past few years. Parts in scarce supply include high-performance components, especially combustion, turbine and exhaust parts such as high-pressure turbine blades, as well as castings, forgings and controls.

The unanticipated volume of new-generation engine early shop visits is consuming labor and facilities that otherwise would have been available to serve the surge in legacy engine MRO. While new-generation engines rely on different capacity—namely, OEM closed-network MRO providers—most shops serve both new and legacy engines. Resolving quality and durability issues to reduce the volume of these visits will take several years.

The global shortage of skilled labor, especially experienced workers, will be an ongoing challenge for MRO shops. In the U.S., demand for aircraft mechanics and service technicians is projected to rise roughly 4% by 2030, according to the U.S. Bureau of Labor Statistics, significantly outpacing the projected 1% growth of the working-age population in the same period, indicating tight labor markets. The same trend will affect other regions with large MRO workforces, including China, Singapore, Japan, Brazil and Europe, where working-age populations are projected by the World Bank to remain flat or decline.

If MRO capacity growth continues at historical rates, our analysis indicates the cumulative demand for shop visits through the end of the decade will exceed supply by nearly 17%. That shortfall, in turn, would impede air traffic growth by forcing operators to limit flights and routes. Unless MRO companies act quickly to close this capacity gap, airlines will face higher costs to operate constrained fleets. That financial burden, on top of growing costs to decarbonize air travel, is likely to slow passenger travel growth.

Navigating The Squeeze

Tomorrow’s winners are investing to increase capacity by improving shop efficiency and productivity ahead of the next demand surge. They are also working with customers to forecast MRO demand to help mitigate maintenance delays. That entails developing a detailed outlook for each aircraft platform served, including estimates of expected shop visit intervals for next-generation engines, which are still far from maturity.

Technology can also help improve productivity, especially artificial intelligence (AI) and automation. For instance, computer vision is improving the accuracy and speed of inspections and boosting the productivity of smaller workforces. AI also can be used to improve knowledge management and employee decision-making and productivity, bringing together disparate data to help technicians better diagnose, troubleshoot and prescribe workflows. That can speed up lengthy process steps like repair approvals while improving outcomes and reducing the time required to train new technicians.

Leaders are also investing in parts repair and USM. The main reason for today’s slow TATs is a shortage of engine parts. One way to improve TAT is by expanding piece-part repair capacity and access to USM. By boosting the supply of used and repaired parts, MRO providers help relieve the overall demand for new OEM parts, further reducing repair queues.

The engine maintenance capacity crunch presents significant challenges but also offers substantial opportunities for MRO providers and suppliers. By investing in productivity, parts repair and scaling capabilities, companies can navigate this complex landscape and emerge as leaders in the industry.

Jim Harris is a partner at Bain & Company and leads the firm’s global Aerospace and Defense practice. Michael Sion is a partner in Bain’s Advanced Manufacturing and Services practice.