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  <xsd:element name="AmortizationOfDeferredCertificationAndDryDockCosts" id="hlx_AmortizationOfDeferredCertificationAndDryDockCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PaymentsForDeferredCertificationAndDryDockCosts" id="hlx_PaymentsForDeferredCertificationAndDryDockCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="HelixEnergySolutionsMember" id="hlx_HelixEnergySolutionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="HornbeckMember" id="hlx_HornbeckMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="EquityOwnershipPercentage" id="hlx_EquityOwnershipPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
</xsd:schema>
