Engine OEMs and the Aftermarket MRO Business Model

Introduction

The jet engine business is one of the most studied and admired business models in all of industrials, and understanding it is essential for anyone covering aerospace and defense. The model works on a simple but powerful principle: sell the engine at a low margin (or even a loss) to secure a position on an aircraft platform, then earn outsized returns on spare parts, maintenance, repair, and overhaul (MRO) services for the 20-30 year life of that engine. Every LEAP or GEnx engine delivered today creates decades of recurring, high-margin aftermarket cash flow that dwarfs the economics of the initial equipment sale.

GE Aerospace, the largest engine OEM, reported revenue of $45.9 billion in 2025 (18% growth), with approximately 70% of total revenue derived from aftermarket parts and services rather than new engine deliveries. The company delivered $10 billion in profit, driven by the high-margin aftermarket business. This is not a unique phenomenon: Pratt & Whitney (a division of RTX) saw aftermarket revenue surge 28% in Q1 2025, and Rolls-Royce improved its operating margin from 1% to 17% over five years, driven primarily by aftermarket recovery.

The engine OEM business model is often compared to the razor-and-blade analogy, where a company sells the initial product (the razor, or engine) at a low margin and earns profits from recurring consumables (the blades, or spare parts and maintenance).

Razor-and-Blade Model (Aerospace Engines)

A business model where the initial equipment sale (a jet engine priced at $10-30 million depending on type) generates low or negative margins, while the subsequent stream of aftermarket services (spare parts, overhauls, component repairs) over the engine's 20-30 year service life generates cumulative revenue of 3-5x the initial engine price at margins of 40-60%+. The model works because engines are designed with proprietary parts that only the OEM or its licensed MRO providers can supply, creating a captive aftermarket with near-zero competitive substitution risk.

The economics work as follows. A new LEAP engine (powering the Airbus A320neo and Boeing 737 MAX) has a list price of approximately $15-18 million, though airlines and lessors typically negotiate significant discounts, sometimes receiving engines at or below cost as part of airframe purchase agreements. The OEM accepts this initial margin sacrifice because the engine will require its first major overhaul after approximately 7,000-10,000 flight cycles (roughly 5-7 years of service), and each overhaul costs $3-6 million. Over the engine's 25+ year life, it will undergo multiple overhauls, consume millions of dollars in spare parts, and generate 3-5x its initial selling price in cumulative aftermarket revenue.

GE Aerospace's LEAP engine fleet is now entering the first major overhaul window. LEAP internal shop visits grew 27% in 2025, and spare parts revenue climbed over 25%. Annual LEAP shop visits could roughly quadruple to approximately 2,000 by 2030 as more of the installed fleet reaches overhaul maturity. This accelerating aftermarket wave is why GE Aerospace hit $10 billion in operating profit two years ahead of its original target.

The commercial jet engine market is an oligopoly shared among three primary manufacturers, each with distinct strengths and challenges.

GE Aerospace is the dominant player, with the largest installed base and the highest margins. The company's LEAP engine powers both the A320neo and 737 MAX, and its GE9X engine is the exclusive powerplant for the 777X. GE Aerospace's 26% EBIT margins and strong aftermarket growth have made it one of the highest-valued companies in all of industrials, trading at a significant premium to other A&D companies.

Pratt & Whitney (RTX) competes primarily through its geared turbofan (GTF) engine, which offers fuel efficiency advantages but has experienced significant technical issues requiring fleet-wide inspections and engine removals. The GTF's contaminated powder metal issue has constrained Airbus production rates and forced Pratt & Whitney to allocate resources to retrofit and enhancement programs. Despite these challenges, the aftermarket associated with a large and growing GTF installed base will generate decades of recurring revenue as the fleet matures.

Rolls-Royce specializes in widebody engines (Trent 700, Trent XWB, Trent 1000) and has staged one of the most dramatic turnarounds in industrial history, growing its operating margin from approximately 1% to 17% in five years. The recovery was driven by increasing widebody flight hours (which drive aftermarket revenue through Rolls-Royce's "power-by-the-hour" Total Care contracts), cost restructuring, and pricing discipline. Rolls-Royce's TotalCare model, where airlines pay per engine flight hour rather than for individual maintenance events, is a distinct commercial approach that smooths revenue and aligns OEM and airline incentives.

The engine OEM aftermarket model has implications that extend well beyond the three major engine manufacturers.

Aftermarket exposure drives valuation premiums. Companies with high aftermarket revenue as a percentage of total revenue consistently trade at premium multiples across the A&D supply chain. TransDigm, which generates the majority of its revenue from proprietary aftermarket parts, trades at 15-20x EBITDA. Component suppliers with strong aftermarket positions (Heico, Hexcel) command premiums over suppliers primarily exposed to new production. When bankers value an aerospace company, the aftermarket revenue percentage is one of the most important determinants of the appropriate multiple range.

The MRO market is a distinct deal flow vertical. Independent MRO providers (companies that maintain and overhaul engines, airframes, and components without being the original manufacturer) represent a significant deal flow category. PE sponsors have built platforms in the independent MRO space, acquiring small shops and building scale to compete for airline and lessor maintenance contracts. These businesses benefit from the same installed-base-driven demand as the OEMs but operate at lower margins and with less pricing power.

Power-by-the-hour contracts reshape revenue recognition. Rolls-Royce's TotalCare and similar models from other OEMs are shifting engine economics from episodic (lumpy overhaul events) to recurring (monthly per-flight-hour payments). This revenue model is more predictable, more valued by investors, and changes how bankers model engine-related businesses, moving from event-driven revenue forecasts to flight-hour-driven annuity models.