-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 AVF0nN4paK4TzdVEfJIHLBgwwrrdL2dW/S3GfIM9EQNW57N3eDSFS24gzUfcgUTe
 3UgtoErL3V9tq+1iA3DTLA==

<SEC-DOCUMENT>0001127602-09-016061.txt : 20090724
<SEC-HEADER>0001127602-09-016061.hdr.sgml : 20090724
<ACCEPTANCE-DATETIME>20090724170404
ACCESSION NUMBER:		0001127602-09-016061
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090531
FILED AS OF DATE:		20090724
DATE AS OF CHANGE:		20090724

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Regan Robert J
		CENTRAL INDEX KEY:			0001436244

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-06263
		FILM NUMBER:		09962892

	MAIL ADDRESS:	
		STREET 1:		1100 N WOOD DALE ROAD
		CITY:			WOOD DALE
		STATE:			IL
		ZIP:			60191

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AAR CORP
		CENTRAL INDEX KEY:			0000001750
		STANDARD INDUSTRIAL CLASSIFICATION:	AIRCRAFT & PARTS [3720]
		IRS NUMBER:				362334820
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0531

	BUSINESS ADDRESS:	
		STREET 1:		1100 N WOOD DALE RD
		CITY:			WOOD DALE
		STATE:			IL
		ZIP:			60191
		BUSINESS PHONE:		6302272000

	MAIL ADDRESS:	
		STREET 1:		1100 N WOOD DALE RD
		CITY:			WOOD DALE
		STATE:			IL
		ZIP:			60191

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ALLEN AIRCRAFT RADIO INC
		DATE OF NAME CHANGE:	19700204
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-05-31</periodOfReport>

    <issuer>
        <issuerCik>0000001750</issuerCik>
        <issuerName>AAR CORP</issuerName>
        <issuerTradingSymbol>AIR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001436244</rptOwnerCik>
            <rptOwnerName>Regan Robert J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1100 N WOOD DALE ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>WOOD DALE</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60191</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>VP, GC</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-05-31</value>
                <footnoteId id="F1"/>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>6600</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8199</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The PRSA program provides that the award opportunity will be granted based on performance during the performance period and will have a grant date of May 31, 2009, subject to certification of the achievement of the performance goals.  Certification was made on July 23, 2009.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Jo-Ellen Kiddie, Power of Attorney</signatureName>
        <signatureDate>2009-07-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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