UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K/A

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of Earliest Event Reported): April 14, 2021

AAR CORP.

(Exact name of registrant as specified in its charter)

One AAR Place

1100 N. Wood Dale Road

Wood Dale, Illinois 60191

(Address and Zip Code of Principal Executive Offices)

Registrant’s telephone number, including area code: (630) 227-2000

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

¨       Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨       Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨       Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨       Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule  405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company ¨

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

Election of Director

On April 14, 2021, the Board of Directors of AAR CORP. (the “Company”) filed a Current Report on Form 8-K disclosing that it had appointed Ellen M. Lord to the Company’s Board of Directors effective April 14, 2021. At the time of the report, the Company’s Board of Directors had not yet determined on which committees Ms. Lord would serve as a member. Effective September 28, 2021, the Company’s Board of Directors appointed Ms. Lord to the Compensation Committee and Nominating and Governance Committee.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: September 29, 2021