AIR AAR Corp

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE TO

(Amendment No. 3)

Tender Offer Statement under Section 14(d)(1) or 13(e)(1)

of the Securities Exchange Act of 1934

AAR CORP.

(Name of Subject Company (Issuer) and Filing Person (Offeror))

Common Stock, $1.00 par value

(Title of Class of Securities)

000361105

(CUSIP Number of Class of Securities)

AAR CORP.

Attn: Corporate Secretary

1100 North Wood Dale Road

Wood Dale, IL 60191

(630) 227-2075

(Name, address and telephone number of person authorized to receive notices and communications on behalf of filing person)

Copy to:

Robert J. Minkus, Esq.

Schiff Hardin LLP

233 South Wacker Drive, Suite 6600

Chicago, IL 60606

(312) 258-5584

CALCULATION OF FILING FEE

(1)         The transaction valuation is estimated only for purposes of calculating the filing fee. This amount is based on the offer to purchase for not more than $135,000,000 in aggregate of up to 4,655,172 shares of common stock, par value $1.00 per share, at the minimum tender offer price of $29.00 per share.

(2)         The amount of the filing fee, calculated in accordance with Rule 0-11 under the Securities Exchange Act of 1934, as amended, equals $116.20 per $1,000,000 of the value of the transaction.

x          Check the box if any part of the fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

o            Check the box if filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the statement relates:

Check the following box if the filing is a final amendment reporting the results of the tender offer: o

If applicable, check the appropriate box(es) below to designate the appropriate rule provision(s) relied upon:

This Amendment No. 3 (this “Amendment No. 3”) amends and supplements the Tender Offer Statement on Schedule TO originally filed with the Securities and Exchange Commission (the “Commission”) on April 27, 2015, as amended by Amendment No. 1 filed with the Commission on May 7, 2015 and as further amended by Amendment No. 2 filed with the Commission on May 12, 2015 (such statement, as so amended and as further amended by this Amendment No. 3, the “Schedule TO”), which relates to the offer by AAR CORP., a Delaware corporation (“AAR” or the “Company”), to purchase for cash up to $135 million in value of shares of its common stock, par value $1.00 per share (the “Shares”), at a price of not less than $29.00 nor greater than $32.00 per Share upon the terms and subject to the conditions described in the Offer to Purchase, dated April 27, 2015 (the “Offer to Purchase”), a copy of which was previously filed as Exhibit (a)(1)(A) to the Schedule TO, and in the related Letter of Transmittal (the “Letter of Transmittal,” and, together with the Offer to Purchase, as they may be amended or supplemented from time to time, the “Tender Offer”), a copy of which was previously filed as Exhibit (a)(1)(B) to the Schedule TO.

The information set forth in the Offer to Purchase, as previously amended and supplemented, which was previously filed with the Schedule TO, is hereby expressly incorporated herein by reference, except that such information is hereby further amended and supplemented to the extent expressly provided for herein.

Items 11 and 12 of the Schedule TO, which incorporate by reference the information contained in the Offer to Purchase, as previously amended and supplemented, are hereby further amended and supplemented as follows:

Item 11.  Additional Information.

Item 11 of the Schedule TO is hereby amended and supplemented by adding the following at the end thereof:

“The Tender Offer expired at the end of the day, 12:00 midnight, New York City time, on May 22, 2015. In accordance with the terms of the Tender Offer, we expect to acquire 4,240,088 shares of AAR common stock at an anticipated purchase price of $31.90 per share. On May 26, 2015 we issued a press release announcing the preliminary results of the Tender Offer and another press release providing an update to our restructuring activities. Copies of the press releases are filed as Exhibits (a)(5)(B) and (a)(5)(C) to this Schedule TO and are incorporated herein by reference.”

Item 12.  Exhibits.

Item 12 of the Schedule TO is hereby amended and supplemented by adding the following exhibit:

2

SIGNATURE

After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

3

Exhibit (a)(5)(B)

NEWS

For Immediate Release

AAR CORP. Reports Preliminary Results of Modified Dutch Auction Tender Offer

WOOD DALE, Illinois, May 26, 2015 — AAR CORP. (NYSE: AIR) announced today the preliminary results of its “modified Dutch auction” tender offer to purchase shares of its common stock for an aggregate cash purchase price of not more than $135 million. The tender offer expired at the end of the day, 12:00 midnight, New York City time, on May 22, 2015.

Based on the preliminary count by Computershare Trust Company, N.A., the depositary for the tender offer, a total of 4,240,088 shares of AAR CORP. common stock were properly tendered and not properly withdrawn at or below the expected purchase price of $31.90 per share, including 486,166 shares that were tendered through notice of guaranteed delivery.

In accordance with the terms and conditions of the tender offer, and based on the preliminary share count by the depositary, AAR CORP. expects to acquire 4,240,088 shares of its common stock at an anticipated purchase price of $31.90 per share, for an aggregate cost of approximately $135 million, excluding fees and expenses relating to the tender offer.  As slightly more than $135 million of shares were tendered at or below the anticipated price of $31.90 per share, AAR CORP. intends to exercise its right to accept an additional $258,794 of shares.  As such, no proration is required and all shares validly tendered and not properly withdrawn at or below $31.90 will be accepted for purchase.  The 4,240,088 shares expected to be purchased in the tender offer represent approximately 10.7% of AAR CORP.’s currently issued and outstanding shares of common stock.

The number of shares to be purchased and the price per share are preliminary, subject to verification by the depositary and subject to change.  The preliminary information is based on the assumption that all shares tendered through notice of guaranteed delivery will be delivered within the three business day settlement period.  The actual number of shares to be purchased and the final price per share will be announced following expiration of the guaranteed delivery period and completion of the confirmation process.  Payment for the shares accepted for purchase, and the return of all other shares tendered and not purchased, will occur promptly thereafter.  Payment for shares will be made in cash, less any applicable withholding taxes and without interest.

Wells Fargo Securities, LLC acted as dealer manager for the tender offer. Stockholders who have questions or would like additional information about the tender offer may contact the information agent for the tender offer, D.F. King & Co., Inc. at: (866) 387-0770 (toll-free), or in writing at: 48 Wall Street 22nd Floor, New York, NY 10005.

About AAR

AAR is a global aerospace and defense company that employs more than 5,000 people in over 20 countries. Based in Wood Dale, Illinois, AAR supports commercial, government and defense customers through two operating segments: Aviation Services and Expeditionary Services. AAR’s Aviation Services include inventory management; parts supply; OEM parts distribution; aircraft maintenance, repair and overhaul; and component repair. AAR’s Expeditionary Services include airlift operations; mobility systems; and command and control centers in support of military and humanitarian missions. More information can be found at www.aarcorp.com.

Contact: John C. Fortson, Vice President, Chief Financial Officer and Treasurer | (630) 227-2075 | john.fortson@aarcorp.com.

Forward-Looking Statements

This press release contains certain statements relating to future results, which are forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995.  These forward-looking statements are based on beliefs of Company management, as well as assumptions and estimates based on information currently available to the Company, and are subject to certain risks and uncertainties that could cause actual results to differ materially from historical results or those anticipated, including those factors discussed under Item 1A, entitled “Risk Factors”, included in the Company’s Form 10-K for the fiscal year ended May 31, 2014. Should one or more of these risks or uncertainties materialize adversely, or should underlying assumptions or estimates prove incorrect, actual results may vary materially from those described.  These events and uncertainties are difficult or impossible to predict accurately and many are beyond the Company’s control.  The Company assumes no obligation to update any forward-looking statements to reflect events or circumstances after the date of such statements or to reflect the occurrence of anticipated or unanticipated events. For additional information, see the comments included in AAR’s filings with the Securities and Exchange Commission.

Exhibit (a)(5)(C)

NEWS

For Immediate Release

AAR CORP. Provides an Update to its Restructuring Activities

WOOD DALE, Illinois, May 26, 2015 — AAR CORP. (NYSE: AIR) announced earlier today that it completed the “modified Dutch auction” tender offer to purchase shares of its common stock for an aggregate cash purchase price of $135 million.  With the execution of the tender the Company expects to retire 4.2 million shares at $31.90 per share, leaving a fully diluted share count of 34.9 million shares as it enters the First Quarter of Fiscal Year 2016.

“We entered Fiscal Year 2015 with a three phase plan to streamline and focus the Company on aviation and expeditionary services and to return capital to shareholders,” said David P. Storch, Chairman and Chief Executive Officer of AAR.  “The first phase of this transformation was the sale of the Telair Cargo Group allowing us to focus our capital and resources towards our industry leading services business.”

Storch continued, “In the second phase we are using the proceeds from the sale to pay down our debt (reducing our interest expense by $25 million per year) and to return capital to our shareholders by buying shares through this tender offer.  Following through on our announced strategy, we will be divesting our Precision Machining business and selling other assets that are no longer a part of our strategy going forward.  These include certain aircraft and inventory no longer required by our airlift business, aircraft in our lease portfolio, as well as inventory in our supply chain and MRO businesses that is excess to our needs or where we are exiting certain product lines. Excluding the sale of Precision Machining, we expect to generate $55-$70 million in cash from these actions and incur $55-$70 million in charges in the Fourth Quarter.  We anticipate some of the asset sales to continue in the First Quarter of our Fiscal Year 2016.  We have also taken action to reduce our corporate costs by approximately $8 million per year.”

Storch concluded, “As we enter the third phase of building a best in class aviation and expeditionary services company we find ourselves in a strong financial position to build out our strategy as we have improved our leverage profile and our cash on hand plus unused capacity is in excess of $500 million.  We expect to invest opportunistically in expanding our service, supply chain and mission critical operational capabilities to expand our leadership positions.”

About AAR

AAR is a global aerospace and defense company that employs more than 5,000 people in over 20 countries. Based in Wood Dale, Illinois, AAR supports commercial, government and defense customers through two operating segments: Aviation Services and Expeditionary Services. AAR’s Aviation Services include inventory management; parts supply; OEM parts distribution; aircraft maintenance, repair and overhaul; and component repair. AAR’s Expeditionary Services include airlift operations; mobility systems; and command and control centers in support of military and humanitarian missions. More information can be found at www.aarcorp.com.

Contact: John C. Fortson, Vice President, Chief Financial Officer and Treasurer | (630) 227-2075 | john.fortson@aarcorp.com.

This press release contains certain statements relating to future results, which are forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995.  These forward-looking statements are based on beliefs of Company management, as well as assumptions and estimates based on information currently available to the Company, and are subject to certain risks and uncertainties that could cause actual results to differ materially from historical results or those anticipated, including those factors discussed under Item 1A, entitled “Risk Factors”, included in the Company’s Form 10-K for the fiscal year ended May 31, 2014. Should one or more of these risks or uncertainties materialize adversely, or should underlying assumptions or estimates prove incorrect, actual results may vary materially from those described.  These events and uncertainties are difficult or impossible to predict accurately and many are beyond the Company’s control.  The Company assumes no obligation to update any forward-looking statements to reflect events or circumstances after the date of such statements or to reflect the occurrence of anticipated or unanticipated events. For additional information, see the comments included in AAR’s filings with the Securities and Exchange Commission.