AAR's CFO Shift: Insider Tapped for Continuity Amid Strategic Growth

WOOD DALE, IL – December 04, 2025 – In a move that underscores a commitment to strategic continuity, aerospace and defense solutions provider AAR CORP. has named Sarah Flanagan, a 13-year company veteran, as its Interim Chief Financial Officer. The appointment, effective December 11, follows the departure of Sean Gillen, who helmed the company's finances for seven years and is leaving to pursue an opportunity outside the aviation industry.

While any C-suite transition invites scrutiny, AAR’s decision to promote from within signals a vote of confidence in its internal talent and current strategic direction. Flanagan steps into the role at a pivotal moment for the company, which is navigating a period of robust growth and aggressive market positioning. The transition is less a course correction and more a changing of the guard, placing a deeply experienced internal leader at the financial controls of a company in high flight.

A Legacy of Strategic Repositioning

Sean Gillen’s departure marks the end of a significant chapter for AAR. His seven-year tenure as CFO was defined by a deliberate and successful effort to reshape the company’s portfolio. In a statement, Chairman, President, and CEO John M. Holmes credited Gillen directly, noting his “experience has played a key role in executing on our strategy to reposition and enhance AAR's portfolio to focus on higher growth, higher margin businesses.”

This repositioning was not merely theoretical. Under Gillen’s financial stewardship, AAR executed key strategic moves, including the acquisition of its Product Support business in late fiscal 2024, a deal that significantly contributed to the company’s impressive 20% sales growth in fiscal 2025, which saw revenue climb to $2.8 billion. This focus on higher-margin activities is evident in the numbers; AAR’s adjusted operating margin climbed from 8.3% to 9.6% in fiscal 2025, a testament to the success of the strategy.

Furthermore, Gillen oversaw a crucial strengthening of the balance sheet. Following the Product Support acquisition, the company’s net leverage was reduced from 3.58x to a more manageable 2.72x by the end of fiscal 2025. This deleveraging provides his successor with greater financial flexibility to pursue further growth, whether through organic investment or strategic M&A. Gillen leaves AAR on a solid financial footing, having successfully executed a complex, multi-year strategy that has made the company leaner, more profitable, and better positioned for the future.

Continuity Through Deep Bench Strength

For investors and market watchers, the appointment of Sarah Flanagan as Interim CFO should be a reassuring signal of stability. Her career at AAR is a case study in internal talent development. Since joining in 2012, she has held roles of increasing importance, including serving as Group Chief Financial Officer for Aviation Services, the company’s largest business segment. This role gave her an intimate understanding of the operational and financial drivers of AAR’s core business.

Since 2017, as Vice President of Financial Operations, Flanagan has led the global finance and contracts organizations, making her a central figure in the company's financial architecture. Her promotion to an Officer of the Company in the same year further cemented her status as a key member of the leadership team. CEO John M. Holmes highlighted this deep-rooted experience, stating, “Sarah brings vast industry knowledge and extensive experience across AAR's global operations. Sarah and I have worked closely during her 13 years at AAR, and I am excited she will lead our finance organization during this interim period.”

Flanagan's credentials extend beyond her long tenure at AAR. Her 11 years at Honeywell’s Aerospace unit, where she held senior finance roles including Controller for the $4.5 billion Engines, Systems & Services segment, provided her with invaluable experience at another industry titan. This, combined with her foundational years as an auditor at PricewaterhouseCoopers and her status as a Certified Public Accountant, creates a profile of a finance chief who is not only steeped in AAR’s culture but also possesses a broad and disciplined financial perspective.

Navigating a Buoyant but Demanding Market

Flanagan takes the financial helm as AAR capitalizes on strong tailwinds in the aviation aftermarket. The company recently reported a stellar first quarter for fiscal year 2026, with sales up 12% year-over-year to $740 million and adjusted earnings per share jumping 27%. Organic sales growth was even stronger at 17%, driven by a remarkable 27% surge in its Parts Supply segment, indicating voracious demand for its services.

To meet this demand, AAR is investing heavily in its future. The company is expanding its airframe maintenance facilities in Miami and Oklahoma City, with completion expected in early to mid-2026. It also recently acquired Aerostrat to bolster its Trax software suite, a move that enhances its digital capabilities in the MRO space. These investments are crucial for maintaining momentum but will require disciplined financial oversight to ensure they deliver projected returns.

While the market is strong, the aerospace and defense industry continues to face significant headwinds, including persistent supply chain disruptions and a highly competitive market for skilled labor. Gillen’s departure for an opportunity outside aviation is itself a reflection of the broader talent retention challenges facing the sector, as professionals are lured away by other industries. Flanagan’s immediate task will be to ensure financial discipline and support these strategic growth initiatives while navigating these external pressures.

The Interim Question and Future Trajectory

The designation of “Interim” CFO naturally raises questions about AAR’s long-term leadership plan. The company has not announced a formal search for a permanent replacement, and it is common for firms to use an interim period to evaluate an internal candidate’s performance in the top role. Given Flanagan’s extensive experience, deep integration within the company, and the CEO’s public endorsement, she is undoubtedly a leading contender for the permanent position.

Her appointment allows AAR to maintain its strategic trajectory without the disruption that an external hire might bring. She is already familiar with the intricacies of the portfolio repositioning that Gillen oversaw and is well-positioned to continue the focus on margin expansion and operational efficiency. The coming months will serve as a real-world audition, giving the board an opportunity to assess her leadership at the highest level. For now, AAR has chosen a steady hand to guide its financial strategy, ensuring that the company remains on its upward flight path without turbulence in-flight turbulence.