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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0000938166-10-000008.txt : 20100520
<SEC-HEADER>0000938166-10-000008.hdr.sgml : 20100520
<ACCEPTANCE-DATETIME>20100520142338
ACCESSION NUMBER:		0000938166-10-000008
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100518
FILED AS OF DATE:		20100520
DATE AS OF CHANGE:		20100520

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			FLANNERY KEVIN S
		CENTRAL INDEX KEY:			0001159879

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34595
		FILM NUMBER:		10847461

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ATS CORP
		CENTRAL INDEX KEY:			0001325460
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-MANAGEMENT CONSULTING SERVICES [8742]
		IRS NUMBER:				113747950
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		7925 JONES BRANCH DRIVE
		CITY:			MCLEAN
		STATE:			VA
		ZIP:			22102
		BUSINESS PHONE:		571-766-2400

	MAIL ADDRESS:	
		STREET 1:		7925 JONES BRANCH DRIVE
		CITY:			MCLEAN
		STATE:			VA
		ZIP:			22102

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Federal Services Acquisition CORP
		DATE OF NAME CHANGE:	20050429
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-05-18</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001325460</issuerCik>
        <issuerName>ATS CORP</issuerName>
        <issuerTradingSymbol>ATSC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001159879</rptOwnerCik>
            <rptOwnerName>FLANNERY KEVIN S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>7925 JONES BRANCH DR.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MCLEAN</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>22102</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-05-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>8275</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>67659</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents restricted shares under the terms of the 2006 Omnibus Incentive Compensation Plan, of which 100% vest on May 1, 2011.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Kevin S. Flannery</signatureName>
        <signatureDate>2010-05-20</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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