Additional Proxy Soliciting Materials (Form DEFA14A)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No.  )

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

HEXCEL CORPORATION

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check all boxes that apply):

HEXCEL CORPORATION

Two Stamford Plaza, 281 Tresser Boulevard

Stamford, Connecticut 06901

SUPPLEMENT TO PROXY STATEMENT

RELATED TO ANNUAL MEETING OF STOCKHOLDERS

TO BE HELD ON MAY 14, 2026

This proxy statement supplement, dated May 8, 2026 (this "supplement"), is furnished to the holders of common stock of Hexcel Corporation ("Hexcel," the "company," "we," "us" or "our") in connection with the solicitation of proxies by Hexcel on behalf of the board of directors of the company (the "board of directors" or the "board") for use at the Annual Meeting of Stockholders, or any adjournments or postponements thereof, to be held on May 14, 2026 (the "Annual Meeting"). This supplement is being filed with the SEC and will be made available to stockholders at www.proxyvote.com.

The purpose of this supplement is solely to update the biographical information in the proxy statement for Nick L. Stanage, a member of our board, who is standing for re-election at the Annual Meeting. On May 7, 2026, the board of directors of AMETEK, Inc. ("AMETEK"), a publicly-traded global provider of industrial technology solutions, appointed Mr. Stanage to serve as a director of AMETEK.

Except as described in this supplement, none of the items or information presented in the proxy statement is affected by this supplement. This supplement does not provide all of the information that is important to your voting decisions at the Annual Meeting. The proxy statement contains other important additional information. We encourage you to carefully read this supplement together with the proxy statement, including the rest of Mr. Stanage's biography on page 10 of the proxy statement.

If you have already submitted your proxy, you do not need to take any action unless you wish to change your vote. This supplement does not change the proposals to be acted upon at the Annual Meeting, which are described in the proxy statement.

IMPORTANT NOTICE REGARDING THE

AVAILABILITY OF PROXY MATERIALS FOR THE

ANNUAL MEETING OF STOCKHOLDERS TO BE HELD ON MAY 14, 2026

This supplement, the proxy statement, the annual report to stockholders and related materials are available at www.proxyvote.com.