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  <xsd:element name="StockIssuedDuringPeriodSharesRetirementOfConvertibleDebt" id="hlx_StockIssuedDuringPeriodSharesRetirementOfConvertibleDebt" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="PaymentsOfAccruedInterest" id="hlx_PaymentsOfAccruedInterest" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="MeasurementInputChangeInControlEventMember" id="hlx_MeasurementInputChangeInControlEventMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ConvertibleDebtConversionValuePaidInExcessOfCarryingAmount" id="hlx_ConvertibleDebtConversionValuePaidInExcessOfCarryingAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="FairValueDebtInstrumentConvertibleAssociatedCappedCallsUponTermination" id="hlx_FairValueDebtInstrumentConvertibleAssociatedCappedCallsUponTermination" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="NumberOfPlugAndAbandonmentSystems" id="hlx_NumberOfPlugAndAbandonmentSystems" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="DebtInstrumentTenderedForConversionPrincipalAmount" id="hlx_DebtInstrumentTenderedForConversionPrincipalAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DebtInstrumentAmountSubjectToRedemption" id="hlx_DebtInstrumentAmountSubjectToRedemption" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="PrivatelyNegotiatedAgreementMember" id="hlx_PrivatelyNegotiatedAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DecemberNotesTenderedForConversionMember" id="hlx_DecemberNotesTenderedForConversionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ProductionMaximizationMember" id="hlx_ProductionMaximizationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DecommissioningMember" id="hlx_DecommissioningMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RenewablesMember" id="hlx_RenewablesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NotesSubjectToRedemptionInMarchMember" id="hlx_NotesSubjectToRedemptionInMarchMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="OtherNonoperatingIncomeExpenseAndRoyaltyIncome" id="hlx_OtherNonoperatingIncomeExpenseAndRoyaltyIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="DebtInstrumentConvertibleRemainingPrincipalAmountSubjectToRedemption" id="hlx_DebtInstrumentConvertibleRemainingPrincipalAmountSubjectToRedemption" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="GainLossOnConvertibleDebtInstrument" id="hlx_GainLossOnConvertibleDebtInstrument" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="OwenKratzMember" id="hlx_OwenKratzMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
</xsd:schema>
