-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
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 jokq0wsm+3yG6dIvOf8pIQ==

<SEC-DOCUMENT>0000001750-05-000005.txt : 20050106
<SEC-HEADER>0000001750-05-000005.hdr.sgml : 20050106
<ACCEPTANCE-DATETIME>20050106104740
ACCESSION NUMBER:		0000001750-05-000005
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20041222
FILED AS OF DATE:		20050106
DATE AS OF CHANGE:		20050106

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

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ROMENESKO TIMOTHY J
		CENTRAL INDEX KEY:			0001027737
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0531

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-06263
		FILM NUMBER:		05514709

	BUSINESS ADDRESS:	
		STREET 1:		C/O AAR CORP
		STREET 2:		1111 NICHOLAS BLVD
		CITY:			ELK GROVE VILLAGE
		STATE:			IL
		ZIP:			60007
		BUSINESS PHONE:		8474393939

	MAIL ADDRESS:	
		STREET 1:		C/O AAR CORP
		STREET 2:		1111 NICHOLAS BLVD
		CITY:			1111 NICHOLAS BLVD
		STATE:			IL
		ZIP:			60007
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>c0001027737d20050106f4af.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2004-12-22</periodOfReport>

    <dateOfOriginalSubmission>2004-12-23</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001027737</rptOwnerCik>
            <rptOwnerName>ROMENESKO TIMOTHY 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</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>14.53</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-12-22</value>
                <footnoteId id="F1"/>
            </transactionDate>
            <deemedExecutionDate>
                <value>2004-12-23</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>4790</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2004-12-22</value>
            </exerciseDate>
            <expirationDate>
                <value>2013-07-21</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>4790</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4790</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Reload option resulting from withholding of stock in payment of exercise price.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Jo-Ellen Kiddie, Power of Attorney</signatureName>
        <signatureDate>2005-01-06</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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