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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 GFIsMwc3zhwwfi6y/in2Sj7HZgCabyAWTMn02VJnrmytbM9cWR6G5umda0gMxc2V
 4rXa9Vo7Qj0ymENz+4CK1A==

<SEC-DOCUMENT>0000001750-08-000058.txt : 20081007
<SEC-HEADER>0000001750-08-000058.hdr.sgml : 20081007
<ACCEPTANCE-DATETIME>20081007121222
ACCESSION NUMBER:		0000001750-08-000058
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080601
FILED AS OF DATE:		20081007
DATE AS OF CHANGE:		20081007

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Poulton Richard J.
		CENTRAL INDEX KEY:			0001381542

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-06263
		FILM NUMBER:		081111649

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		7735512676

	MAIL ADDRESS:	
		STREET 1:		3646 WESTFIELD LANE
		CITY:			GLENVIEW
		STATE:			IL
		ZIP:			60026

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>doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-06-01</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001381542</rptOwnerCik>
            <rptOwnerName>Poulton Richard 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>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice President-CFO &amp; Treasurer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>25000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>19.28</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-06-01</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2008-10-06</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>19.28</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2009-06-01</value>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2018-06-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>10000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Grantee may elect to pay the exercise price of the option or any tax withholding obligation in connection therewith by directing the Company to withhold a portion of the shares otherwise distributable to the grantee upon exercise or by transferring to the Company previously acquired shares, valued at their fair market value on such taxable date.</footnote>
        <footnote id="F2">The option vests in five equal installments beginning on June 1, 2009.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Jo-Ellen Kiddie</signatureName>
        <signatureDate>2008-10-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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