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  <xs:element id="fsk_BorrowingsTypeOfLendersAxis" abstract="true" name="BorrowingsTypeOfLendersAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fsk_BorrowingsTypeOfLendersDomain" abstract="true" name="BorrowingsTypeOfLendersDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsk_NonExtendingLendersLendersOtherThanNonExtendingMember" abstract="true" name="NonExtendingLendersLendersOtherThanNonExtendingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsk_LenderOtherThanNonExtendingLendersAlternateBaseRateGreaterThanOrEqualToMember" abstract="true" name="LenderOtherThanNonExtendingLendersAlternateBaseRateGreaterThanOrEqualToMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsk_LenderOtherThanNonExtendingLendersAlternateBaseRateLessThanMember" abstract="true" name="LenderOtherThanNonExtendingLendersAlternateBaseRateLessThanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsk_LenderOtherThanNonExtendingLendersTermBenchmarkGreaterThanOrEqualToMember" abstract="true" name="LenderOtherThanNonExtendingLendersTermBenchmarkGreaterThanOrEqualToMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsk_LenderOtherThanNonExtendingLendersTermBenchmarkLessThanMember" abstract="true" name="LenderOtherThanNonExtendingLendersTermBenchmarkLessThanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsk_NonExtendingLendersMember" abstract="true" name="NonExtendingLendersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsk_NonExtendingLendersTermBenchmarkLessThanMember" abstract="true" name="NonExtendingLendersTermBenchmarkLessThanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsk_NonExtendingLendersAlternateBaseRateGreaterThanOrEqualToMember" abstract="true" name="NonExtendingLendersAlternateBaseRateGreaterThanOrEqualToMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsk_NonExtendingLendersAlternateBaseRateLessThanMember" abstract="true" name="NonExtendingLendersAlternateBaseRateLessThanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsk_NonExtendingLendersTermBenchmarkGreaterThanOrEqualToMember" abstract="true" name="NonExtendingLendersTermBenchmarkGreaterThanOrEqualToMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsk_OvernightBankFundingRateMember" abstract="true" name="OvernightBankFundingRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsk_LineOfCreditFacilityAccordionFeatureIncreaseLimit" abstract="false" name="LineOfCreditFacilityAccordionFeatureIncreaseLimit" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fsk_DebtInstrumentBorrowingRateTestThreshold" abstract="false" name="DebtInstrumentBorrowingRateTestThreshold" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="fsk_DebtInstrumentAlternativeBaseRateBasisSpread" abstract="false" name="DebtInstrumentAlternativeBaseRateBasisSpread" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fsk_DebtInstrumentCovenantDebtServiceCoverageRatioMinimum" abstract="false" name="DebtInstrumentCovenantDebtServiceCoverageRatioMinimum" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
</xs:schema>
