AIR Aerospace & Defense · Aviation aftermarket · MRO · Government contractor · Thesis updated July 27, 2026

AAR reshapes its portfolio but integration risks weigh on margins

FY26 sales grew rapidly, driven by strong commercial demand and four new acquisitions.
The company realigned into four segments in Q4 FY26, winding down its legacy commercial asset programs.
Cash flow turned positive earlier in the year, helping answer old bear case concerns about capital intensity.
Repair, Engineering, and Software margins face pressure as the company integrates the lower-margin HAECO Americas business.

01 Running thesis

A cleaner portfolio meets integration reality

AAR has taken bold steps to simplify its business. In late fiscal 2026, the company reorganized its segments and began a multi-year exit from its asset-heavy Legacy Commercial Programs. This move aims to free up capital and boost returns by focusing on higher-margin parts, engineering, and software.

The bull case points to strong commercial demand and rapid growth from recent acquisitions. AAR bought four companies in FY26, including ADI and HAECO Americas, adding scale to its distribution and repair networks. Cash generation has also improved over the past year, easing fears that growth was burning too much capital.

The bear case shifts from cash burn to execution risk. AAR is managing a complex transition. It must wind down a legacy business while integrating multiple acquisitions. The HAECO Americas deal, in particular, dragged down operating margins in the repair segment earlier in the year, proving that buying growth comes with integration headaches.

Jul 2026▲The FY26 10-K revealed a major segment realignment and the wind-down of legacy asset-heavy programs, shifting focus to capital-light growth and integration execution.

Mar 2026→Q3 FY26 sales growth accelerated to 24.6%, and nine-month operating cash flow turned positive at $43.4 million. The view stayed balanced because HAECO Americas drove clear margin pressure.

Jan 2026→Q2 FY26 showed faster sales growth and better government margins. Negative operating cash flow and early HAECO margin pressure kept the risk side active.

Sep 2025→Q1 FY26 confirmed growth in Parts Supply, with consolidated sales up 11.8%. Cash use rose because of inventory investment, keeping growth quality in focus.

Jul 2025▲The FY2025 10-K showed sales up 19.9% and stronger Repair & Engineering profit after the Product Support acquisition. A new Section 232 trade investigation added a watch item.

Mar 2025→The Product Support deal looked accretive, but the Landing Gear Overhaul exit created a large impairment charge. The portfolio looked cleaner, while reported profit took a hit.

02 Business model

An independent shop for aircraft uptime

AAR makes money by supporting aircraft after they are built. Airlines, defense agencies, and governments rely on the company for replacement parts, airframe maintenance, logistics, and planning software.

The company recently shifted its strategy to focus on capital-light, higher-margin work. Parts Supply, its largest segment, distributes new parts and used serviceable material. Repair, Engineering, and Software handles heavy maintenance and digital planning tools. Government Solutions manages fleets and logistics for defense customers.

The model historically broke down when working capital needs spiked or when acquired businesses carried lower margins. By winding down its asset-heavy legacy programs, AAR hopes to solve the capital intensity problem, leaving integration execution as the main variable for investors to watch.

03 Product portfolio

Four realigned ways AAR gets paid

Growth engine

Parts Supply

The largest segment, distributing new OEM parts and used serviceable material. It drove significant growth in FY26.

Growth engine

Repair, Engineering, and Software

Provides heavy airframe maintenance, engineering, and planning software. HAECO Americas added scale but pressured margins.

Steady

Government Solutions

Combines fleet management and logistics for defense customers with mobility systems like pallets and shelters.

Cash cow

Legacy Commercial Programs

Asset-heavy flight hour programs now in a multi-year wind-down phase to free up capital.

04 Business segments

Parts drive the new mix

Parts Supply45%growing fast

Repair, Engineering, and Software30%growing fast

Government Solutions20%modest

Legacy Commercial Programs5%declining

Segment shares reflect the fiscal 2026 full-year mix following the Q4 realignment, where Parts Supply accounted for approximately 45% of sales. The remaining segments are estimated based on historical weighting of the underlying businesses.

05 Risk factors

What could go wrong

HAECO margin drag lasts too long

High impact · Medium odds

The HAECO Americas acquisition brought significant revenue but lower margins to the repair segment. If AAR cannot improve the profitability of these heavy maintenance operations, the deal may add size without enough profit.

We watchRepair, Engineering, and Software operating margins moving back toward historical levels.

Legacy wind-down execution

Medium impact · Medium odds

AAR expects to wind down its Legacy Commercial Programs over three to four years by terminating contracts and selling assets. If asset sales fall short of expectations, the expected cash windfall could disappoint.

We watchCash flow generated from the liquidation of rotable assets in the legacy segment.

Section 232 tariffs hit aircraft parts

High impact · Medium odds

A pending U.S. Department of Commerce Section 232 investigation covers imports of commercial aircraft and parts. New tariffs or trade limits could raise costs or disrupt buying patterns across AAR's parts network.

We watchAny Department of Commerce decision tied to the Section 232 aerospace import investigation.

Boeing strike disruptions

Medium impact · Medium odds

Labor issues, such as the union work stoppage at Boeing, can shock the commercial aviation supply chain. Such disruptions could impact AAR's near-term parts distribution volumes.

We watchUpdates on the Boeing strike and management commentary on supply chain ripple effects.

06 Quick answers

In one breath

What does AAR Corp. actually do?

AAR supports aircraft after they are built. It sells parts, repairs aircraft, runs aviation logistics programs, and provides planning software.

Why is AAR winding down its legacy commercial programs?

The company decided the asset-heavy flight hour programs required too much capital and did not meet its return thresholds, opting to free up that cash for higher-margin areas.

What is the main risk after the HAECO Americas acquisition?

The main risk is margin pressure. HAECO Americas added significant sales to the repair segment, but its lower profitability dragged down overall margins initially.