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<!-- Creation Date :2023-10-31T18:43:28.5775+00:00 -->
<!-- Copyright (c) 2023 Donnelly Financial Solutions, Inc. All Rights Reserved. -->
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  <xsd:element id="psn_ReconciliationFromNetIncomeToAdjustedEBITDAAbstract" name="ReconciliationFromNetIncomeToAdjustedEBITDAAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_ConstructionEquipmentMember" name="ConstructionEquipmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_MobilitySolutionsMember" name="MobilitySolutionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesRightOfUseAssets" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesRightOfUseAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_RatioOfSellingShareholdersMultiplier" name="RatioOfSellingShareholdersMultiplier" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLongTermLeaseLiabilities" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLongTermLeaseLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_DebtInstrumentConvertibleBusinessPeriod" name="DebtInstrumentConvertibleBusinessPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_AdjustmentToDeferredTaxAssetThroughRetainedEarnings" name="AdjustmentToDeferredTaxAssetThroughRetainedEarnings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_StockRepurchaseProgramCommencementDate" name="StockRepurchaseProgramCommencementDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_EquityBasedCompensationIncomeExpense" name="EquityBasedCompensationIncomeExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_PercentageOfConvertibleSeniorNotesRepurchasedAtCash" name="PercentageOfConvertibleSeniorNotesRepurchasedAtCash" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="psn_DebtInstrumentNumberOfSharesIssuableUponConversion" name="DebtInstrumentNumberOfSharesIssuableUponConversion" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_FiniteLivedIntangibleAssetsAmortizableAmount" name="FiniteLivedIntangibleAssetsAmortizableAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_PercentageOfBondHedgeAndWarrantTransactionsIncreasedConversionPrice" name="PercentageOfBondHedgeAndWarrantTransactionsIncreasedConversionPrice" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_PaymentsForTaxesPaidOnVestedStock" name="PaymentsForTaxesPaidOnVestedStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_SealingTechnologiesIncMember" name="SealingTechnologiesIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_AdjustedEBITDAAttributableToNoncontrollingInterests" name="AdjustedEBITDAAttributableToNoncontrollingInterests" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_OtherIncomeExpense" name="OtherIncomeExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ReimbursableCostIncurred" name="ReimbursableCostIncurred" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_CostPlusMember" name="CostPlusMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_ScheduleOfBalanceSheetInformationRelatedToLeasesTableTextBlock" name="ScheduleOfBalanceSheetInformationRelatedToLeasesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_LesseeLeaseOptionToTerminate" name="LesseeLeaseOptionToTerminate" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesLongTermLeaseLiabilities" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesLongTermLeaseLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_AllegedViolationOfFalseClaimsActMember" name="AllegedViolationOfFalseClaimsActMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_ISEngineersLLCMember" name="ISEngineersLLCMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_EngineeredSystemsMember" name="EngineeredSystemsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_PercentageOfPrincipalAmountToRedeemConvertibleSeniorNotes" name="PercentageOfPrincipalAmountToRedeemConvertibleSeniorNotes" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="psn_CostOfConvertibleNoteHedgeTransaction" name="CostOfConvertibleNoteHedgeTransaction" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_OperatingLeaseNotYetCommencedExpense" name="OperatingLeaseNotYetCommencedExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_IncreaseInOperatingIncome" name="IncreaseInOperatingIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_DirectCostsOfContractsAndSellingGeneralAndAdministrativeExpenseMember" name="DirectCostsOfContractsAndSellingGeneralAndAdministrativeExpenseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_ChangeInContractWithCustomerLiability1" name="ChangeInContractWithCustomerLiability1" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_LesseeLeaseExistenceOfOptionToExtend" name="LesseeLeaseExistenceOfOptionToExtend" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_UnusedTermLoanCommitmentsRate" name="UnusedTermLoanCommitmentsRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_LossContingencyNumberOfClaims" name="LossContingencyNumberOfClaims" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_ConsolidatedJointVenturesMember" name="ConsolidatedJointVenturesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_FinanceLeasesOtherAssetsNoncurrent" name="FinanceLeasesOtherAssetsNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_DebtInstrumentConvertiblePrincipalAmount" name="DebtInstrumentConvertiblePrincipalAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ContractWithCustomerLiabilityCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent" name="ContractWithCustomerLiabilityCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_EquityMethodInvestmentLossAdjustmentAmount" name="EquityMethodInvestmentLossAdjustmentAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_LegalProceedingsTable" name="LegalProceedingsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_WeightedAverageRemainingLeaseTermAbstract" name="WeightedAverageRemainingLeaseTermAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_DecreaseInEarningsPerShareDiluted" name="DecreaseInEarningsPerShareDiluted" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_ConvertibleNoteConvertedEachAmount" name="ConvertibleNoteConvertedEachAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ChangeInContractWithCustomerAssets1" name="ChangeInContractWithCustomerAssets1" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_LesseeLeaseExistenceOfOptionToTerminate" name="LesseeLeaseExistenceOfOptionToTerminate" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_ScheduleOfFinancialInformationOfConsolidatedJointVenturesTableTextBlock" name="ScheduleOfFinancialInformationOfConsolidatedJointVenturesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesShortTermLeaseLiabilities" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeasesShortTermLeaseLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ContractWithCustomerAdjustmentToRevenueImpactOfChangesInEstimatedClaimsOrIncentivesOverThreshold" name="ContractWithCustomerAdjustmentToRevenueImpactOfChangesInEstimatedClaimsOrIncentivesOverThreshold" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_MinorityInterestIncreaseDecreaseFromContributionsToNoncontrollingInterestHolders" name="MinorityInterestIncreaseDecreaseFromContributionsToNoncontrollingInterestHolders" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ContractWithCustomerAssetLiabilityNet" name="ContractWithCustomerAssetLiabilityNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_LossContingencySoughtValueCivilPenaltyForEachAllegedViolationOfAct" name="LossContingencySoughtValueCivilPenaltyForEachAllegedViolationOfAct" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_FinanceLeaseLiabilityPaymentsDueAfterYearFour" name="FinanceLeaseLiabilityPaymentsDueAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_TransactionRelatedCosts" name="TransactionRelatedCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_SummaryOfChangesInContractAssetsAndContractLiabilitiesTableTextBlock" name="SummaryOfChangesInContractAssetsAndContractLiabilitiesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_RestructuringIncomeExpense" name="RestructuringIncomeExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_EmployeeStockOwnershipPlanMember" name="EmployeeStockOwnershipPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_BusinessAcquisitionProFormaNetIncomeLossIncludingPortionAttributableToNoncontrollingInterest" name="BusinessAcquisitionProFormaNetIncomeLossIncludingPortionAttributableToNoncontrollingInterest" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpensesAndOtherLiabilities" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpensesAndOtherLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_CriticalInfrastructureSegmentMember" name="CriticalInfrastructureSegmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_BondHedgeTerm" name="BondHedgeTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_AmountPaidToAcquireVehiclesForContractorDefendantToPerformSecurityServices" name="AmountPaidToAcquireVehiclesForContractorDefendantToPerformSecurityServices" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_DescriptionOfOperationsDisclosureAbstract" name="DescriptionOfOperationsDisclosureAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_AdditionalPaymentForSellingShareholders" name="AdditionalPaymentForSellingShareholders" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ConnectedCommunitiesMember" name="ConnectedCommunitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_DefenseAndIntelligenceMember" name="DefenseAndIntelligenceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_AmountPaidPerMonthToContractorDefendantByRelatorOnFalseClaims" name="AmountPaidPerMonthToContractorDefendantByRelatorOnFalseClaims" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_ContractWithCustomerAssetLiabilityCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent" name="ContractWithCustomerAssetLiabilityCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_BilledReceivablesCurrent" name="BilledReceivablesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_ChangeInContractWithCustomerAssetsAndLiabilitiesNet" name="ChangeInContractWithCustomerAssetsAndLiabilitiesNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_LegalProceedingsLineItems" name="LegalProceedingsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_AdditionalDeferredTaxLiabilityRelatedToCapitalizedDebtIssuanceCost" name="AdditionalDeferredTaxLiabilityRelatedToCapitalizedDebtIssuanceCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ConvertibleNotesConvertedEachIntoSharesOfCommonStock" name="ConvertibleNotesConvertedEachIntoSharesOfCommonStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_DebtInstrumentConvertibleConsecutiveBusinessDayPeriod" name="DebtInstrumentConvertibleConsecutiveBusinessDayPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedShortTermLeaseLiabilities" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedShortTermLeaseLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_StockRepurchaseAveragePricePaidPerShare" name="StockRepurchaseAveragePricePaidPerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_NetCostOfPurchaseOfBondHedgesAndSaleOfWarrants" name="NetCostOfPurchaseOfBondHedgesAndSaleOfWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_DistributionsFromContributionsToEquityMethodInvestment" name="DistributionsFromContributionsToEquityMethodInvestment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_WeightedAverageDiscountRateAbstract" name="WeightedAverageDiscountRateAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_UnconsolidatedJointVenturesMember" name="UnconsolidatedJointVenturesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_ContractReceivableRetainageAssetLiabilitiesNetDueAfterOneYear" name="ContractReceivableRetainageAssetLiabilitiesNetDueAfterOneYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_AccruedExpensesAndOtherCurrentLiabilities" name="AccruedExpensesAndOtherCurrentLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_IncreaseDecreaseInAccruedExpensesAndOtherCurrentLiabilities" name="IncreaseDecreaseInAccruedExpensesAndOtherCurrentLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_PaymentForEarnOutRevenueTarget" name="PaymentForEarnOutRevenueTarget" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ScheduleOfCashFlowInformationRelatedToLeasesTableTextBlock" name="ScheduleOfCashFlowInformationRelatedToLeasesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_SummaryOfRevenuesAndPropertyAndEquipmentNetByGeographicAreaTableTextBlock" name="SummaryOfRevenuesAndPropertyAndEquipmentNetByGeographicAreaTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_XatorCorporationMember" name="XatorCorporationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_LesseeLeaseOptionToExtend" name="LesseeLeaseOptionToExtend" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_OperatingLeasesAbstract" name="OperatingLeasesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_DecreaseInNetIncomeNetOfTax" name="DecreaseInNetIncomeNetOfTax" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_ContractReceivableRetainageAssetsLiabilitiesNet" name="ContractReceivableRetainageAssetsLiabilitiesNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_TwoThousandTwentyTwoDelayedDrawTermLoanMember" name="TwoThousandTwentyTwoDelayedDrawTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_LeaseLiabilitiesAbstract" name="LeaseLiabilitiesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_IncreaseInNetIncomeNetOfTax" name="IncreaseInNetIncomeNetOfTax" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_InvesteesOtherMember" name="InvesteesOtherMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_FinanceLeasesAbstract" name="FinanceLeasesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_IpkeysPowerPartnersMember" name="IpkeysPowerPartnersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_AdjustmentsToAdditionalPaidInCapitalRepurchasesOfCommonStock" name="AdjustmentsToAdditionalPaidInCapitalRepurchasesOfCommonStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ScheduleOfConsolidatedBalanceSheetRelatedToUnconsolidatedJointVenturesTableTextBlock" name="ScheduleOfConsolidatedBalanceSheetRelatedToUnconsolidatedJointVenturesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_ConvertibleNoteHedgeAndWarrantTransactionMember" name="ConvertibleNoteHedgeAndWarrantTransactionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="psn_TargetAmountOfEarnoutRevenue" name="TargetAmountOfEarnoutRevenue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="psn_ContractWithCustomerAssetCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent" name="ContractWithCustomerAssetCumulativeCatchupAdjustmentToRevenueChangeInMeasureOfProgressPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_ReversalOfDeferredTaxLiability" name="ReversalOfDeferredTaxLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour" name="FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="psn_ScheduleOfMaturitiesOfOperatingAndFinanceLeaseLiabilitiesTableTextBlock" name="ScheduleOfMaturitiesOfOperatingAndFinanceLeaseLiabilitiesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="psn_AdjustedEBITDAAttributableToParent" name="AdjustedEBITDAAttributableToParent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
</xsd:schema>
