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  <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:element name="ContractWithCustomerNetLiabilityAsset" id="hlx_ContractWithCustomerNetLiabilityAsset" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ContractWithCustomerNetLiabilityRevenueRecognized" id="hlx_ContractWithCustomerNetLiabilityRevenueRecognized" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="DetailsOfCertainAccountsAbstract" id="hlx_DetailsOfCertainAccountsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="StockRepurchasedDuringPeriodValueChangeInCompanyStockPlanNetAndOthers" id="hlx_StockRepurchasedDuringPeriodValueChangeInCompanyStockPlanNetAndOthers" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="StockRepurchasedDuringPeriodSharesChangeInCompanyStockPlanNetAndOthers" id="hlx_StockRepurchasedDuringPeriodSharesChangeInCompanyStockPlanNetAndOthers" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DepreciationAndAmortizationExcludingAmortizationOfDeferredRecertificationAndDryDockCosts" id="hlx_DepreciationAndAmortizationExcludingAmortizationOfDeferredRecertificationAndDryDockCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AmortizationOfDeferredRecertificationAndDryDockCosts" id="hlx_AmortizationOfDeferredRecertificationAndDryDockCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PaymentsForDeferredRecertificationAndDryDockCosts" id="hlx_PaymentsForDeferredRecertificationAndDryDockCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AssetBasedCreditAgreementMaturingAugust2029Member" id="hlx_AssetBasedCreditAgreementMaturingAugust2029Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TrymMember" id="hlx_TrymMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TermOfCharterAgreementExtension" id="hlx_TermOfCharterAgreementExtension" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="CashOutflowDuringPeriodForRepurchaseOfCommonStockIncludingExciseTaxPaid" id="hlx_CashOutflowDuringPeriodForRepurchaseOfCommonStockIncludingExciseTaxPaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
</xsd:schema>
