Exhibit 99.1 AAR reports first quarter fiscal year 2026 results Wood Dale, Illinois, September 23, 2025 — AAR CORP. (NYSE: AIR), a leading provider of aviation services to commercial and government operators, MROs, and OEMs, reported today financial results for the fiscal year 2026 first quarter ended August 31, 2025. FIRST QUARTER FISCAL YEAR 2026 HIGHLIGHTS 1 · Sales of $740 million; increased 12$0.95 · Adjusted diluted EPS of $1.08; increased 27$34 million · Adjuste ...