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  <xs:element id="onch_WorkingCapitalLoanOutstanding" name="WorkingCapitalLoanOutstanding" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xs:element id="onch_UnderwritingDiscountGrossProceedsPercentage" name="UnderwritingDiscountGrossProceedsPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_UnderwritersOptionFromProposedPublicOffering" name="UnderwritersOptionFromProposedPublicOffering" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_UnderwritersAgreementMember" name="UnderwritersAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="onch_UnderwriterCashDiscount" name="UnderwriterCashDiscount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xs:element id="onch_DeferredUnderwritingDiscount" name="DeferredUnderwritingDiscount" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_CommitmentsAndContingencyDetailsTable" name="CommitmentsAndContingencyDetailsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="onch_CashUnderwritingDiscountRate" name="CashUnderwritingDiscountRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xs:element id="onch_MaximumPeriodAfterBusinessCombinationInWhichToFileRegistrationStatement" name="MaximumPeriodAfterBusinessCombinationInWhichToFileRegistrationStatement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_NumberOfTradingDays" name="NumberOfTradingDays" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_NumberOfTradingDaysCommencing" name="NumberOfTradingDaysCommencing" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_NumberOfTradingDaysCompletion" name="NumberOfTradingDaysCompletion" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_PercentageOfConversionOfOrdinaryShares" name="PercentageOfConversionOfOrdinaryShares" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_PercentageOfNewlyIssuedShares" name="PercentageOfNewlyIssuedShares" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_PeriodOfTimeWithInWhichRegistrationStatementIsExpectedToBecomeEffective" name="PeriodOfTimeWithInWhichRegistrationStatementIsExpectedToBecomeEffective" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_RedemptionPeriod" name="RedemptionPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_ShareholdersDeficitEquityDetailsTable" name="ShareholdersDeficitEquityDetailsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="onch_WarrantsAndRightsOutstandingExercisableTermAfterBusinessCombination" name="WarrantsAndRightsOutstandingExercisableTermAfterBusinessCombination" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_BusinessAcquisitionPercentageOfVotingInterestsToBeAcquiredOnPostTransactionEntityMinimum" name="BusinessAcquisitionPercentageOfVotingInterestsToBeAcquiredOnPostTransactionEntityMinimum" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_OtherOfferingCosts" name="OtherOfferingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xs:element id="onch_DeferredUnderwritingFees" name="DeferredUnderwritingFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xs:element id="onch_DescriptionOfOrganizationBusinessOperationsLiquidityAndCapitalResourcesTable" name="DescriptionOfOrganizationBusinessOperationsLiquidityAndCapitalResourcesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="onch_InterestToBePayDissolutionExpenses" name="InterestToBePayDissolutionExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xs:element id="onch_InvestmentsMaximumMaturityTerm" name="InvestmentsMaximumMaturityTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_CashUnderwritingFees" name="CashUnderwritingFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xs:element id="onch_WorkingCapital" name="WorkingCapital" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xs:element id="onch_PercentageOfFairMarketValueEqualToNetBalanceInTrustAccount" name="PercentageOfFairMarketValueEqualToNetBalanceInTrustAccount" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_ClassAOrdinarySharesParValue00001PerShareMember" name="ClassAOrdinarySharesParValue00001PerShareMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="onch_AccruedOfferingCosts" name="AccruedOfferingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xs:element id="onch_RedeemableWarrantMember" name="RedeemableWarrantMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="onch_TransactionCosts" name="TransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xs:element id="onch_CantorFitzgeraldCoMember" name="CantorFitzgeraldCoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="onch_UnitsEachConsistingOfOneClassAOrdinaryShareAndOnequarterOfOneRedeemableWarrantMember" name="UnitsEachConsistingOfOneClassAOrdinaryShareAndOnequarterOfOneRedeemableWarrantMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="onch_WarrantsEachWholeWarrantExercisableForOneClassAOrdinaryShareAtAnExercisePriceOf1150PerShareMember" name="WarrantsEachWholeWarrantExercisableForOneClassAOrdinaryShareAtAnExercisePriceOf1150PerShareMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="onch_InterestEarnedOnCashHeldInOperatingBankAccount" name="InterestEarnedOnCashHeldInOperatingBankAccount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xs:element id="onch_PrivatePlacementTextBlock" name="PrivatePlacementTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_PrivatePlacementAbstract" name="PrivatePlacementAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="onch_PrivatePlacementTable" name="PrivatePlacementTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xs:element id="onch_InitialPublicOfferingDisclosureTextBlock" name="InitialPublicOfferingDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_NumberOfWarrantsIssuedPerUnit" name="NumberOfWarrantsIssuedPerUnit" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xs:element id="onch_IncreaseDecreaseInLongTermPrepaidInsurance" name="IncreaseDecreaseInLongTermPrepaidInsurance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xs:element id="onch_DeferredCostsIncludedInAccruedOfferingCosts" name="DeferredCostsIncludedInAccruedOfferingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
</xs:schema>
