[4910-13-P[ DEPARTMENT

OF TRANSPORTATION Federal Aviation Administration 14 CFR

Part

39 [Docket

No. FAA-2008-0808;

Directorate

Identifier 2008-NE-18-AD;

Amendment 39-18288;

AD 2015-20-09] RIN 2120-AA64 Airworthiness

Directives;

General

Electric Company Turboshaft

Engines AGENCY:

Federal Aviation Administration

(FAA),

DOT. ACTION:

Final

rule. SUMMARY:

We

are superseding airworthiness

directives

(AD) 2001-18-06

and

AD 2008-22-16,

for

all General

Electric Company

(GE)

CT58 turboshaft

engines.

AD 2001- 18-06

and

AD 2008-22-16

required recalculating

the lives oflife-limited

rotating

parts using

a repetitive

heavy-lift

(RHL) multiplying

factor

and removal

from service

of parts that exceed

the recalculated

cyclic

or hourly

life limit.

This

new

AD would consolidate AD 2001-18-06

and

AD 2008-22-16,

and furfber

reduce

the

life capability

of certain parts.

This

AD

was prompted

by recalculation

of life

for parts installed

on engines

used in Utility operations,

and

a reduced

life

for compressor

spools

in

all operations.

We

are issuing

this

AD

to prevent

failure

of life-limited

rotating

parts, uncontained

part release, damage

to the engine,

and damage

to the aircraft. DATES:

This

AD

is effective

[INSERT

DATE

35 DAYS AFTER

DATE

OF PUBLICATION

IN THE FEDERAL REGISTER]. The Director

of the Federal Register approved

the incorporation

by reference

of

a certain publication

listed

in this

AD

as of[INSERT

DATE

35 DAYS AFTER

DATE

OF PUBLICATION

IN THE FEDERAL REGISTER].ADDRESSES:ForserviceinformationidentifiedinthisproposedAD,contactGeneralElectricCompany,GEAviation,Room285,OneNeumannWay,Cincinnati,OH,45215;phone:513-552-3272;email:aviation.fleetsupport@ge.com.YoumayviewthisserviceinformationattheFAA,Engine&PropellerDirectorate,12NewEnglandExecutivePark,Burlington,MAForinformationontheavailabilityofthismaterialattheFAA,call781-238-7125.ExaminingtheADDocketYoumayexaminetheADdocketontheInternetathttp://www.regulations.govbysearchingforandlocatingDocketNo.FAA-2008-0808;orinpersonattheDocketManagementFacilitybetween9a.m.and5p.m.,MondaythroughFriday,exceptFederalholidays.TheADdocketcontainsthisAD,theregulatoryevaluation,anycommentsreceived,andotherinformation.TheaddressfortheDocketOffice(phone:800-647-5527)isDocumentManagementFacility,U.S.DepartmentofTransportation,DocketOperations,M-30,WestBuildingGroundFloor,RoomW12-140,1200NewJerseyAvenueSE.,Washington,DC20590.FORFURTHERINFORMATIONCONTACT:ChristopherMcGuire,AerospaceEngineer,EngineCertificationOffice,FAA, Engine&PropellerDirectorate,12NewEnglandExecutivePark,Burlington,MA01803;phone:781-238-7120;fax:781-238-7199;email:chris.mcguire@faa.gov.SUPPLEMENTARYINFORMATION:DiscussionWeissuedanoticeofproposedrulemaking(NPRM)toamend14CFRpart39tosupersedeAD2001-18-06,Amendment39-12432(66FR47575,September13,2001,("AD2001-18-06")andAD2008-22-16,Amendment39-15712(73FR63629,October27,2008,("AD2008-22-16").AD2001-18-06andAD2008-22-16appliedtocertainGECT58turboshaftengines.TheNPRMpublishedintheFederalRegisteronMay1,20152(80FR24852).TheNPRMwaspromptedbyGEupdatingthelifelimitsofcompressorspools.GEalsoupdatedthecalculationmethodforthelifeconsumptionofcompressorspoolsandoflife-lirnitedrotatingpartsflowninUtilityoperations.Thisupdateresultedingenerallyreducedlivesforcompressorspoolsandallotherlife-limitedpartsusedinUtilityoperations.TheNPRMproposedtoconsolidateAD2001-18-06andAD2008-22-16,andfurtherreducethelifecapabilityofcertainparts.WeareissuingthisADtopreventfailureoflife-limitedrotatingparts,uncontainedpartrelease,damagetotheengine,anddamagetotheaircraft.RelatedServiceInformationunder1CFRPart51WereviewedGECT58AlertServiceBulletin(ASB)No.SB72-A0162,Revision16,datedJanuary7,2015.Theserviceinformationdescribesproceduresforcalculatinglifelimitsfortheaffectedlife-limitedrotatingparts.ThisserviceinformationisreasonablyavailablebecausetheinterestedpartieshaveaccesstoitthroughtheirnormalcourseofbusinessorseeADDRESSESforotherwaystoaccessthisserviceinformation.CommentsWegavethepublictheopportunitytoparticipateindevelopingthisAD.ThefollowingpresentsthecommentsreceivedontheNPRMandtheFAA'sresponsetoeachcomment.RequestNewMethodforDeterminingReducedLifeLimitsAARAirliftGroup(AAR)requestedreplacementofthecurrentmethodfordeterminingreducedlifelimitsbecausecurrentlimitsdonotagreewithoperatorsfieldexperience.AARindependenttestingrevealedthatexpiredcriticalrotatingpartsshowednofatiguecracks.Wedisagree.FAA-approvedlifelimitsforrotatingpartsarespecifiedtopreventfatiguecrackinitiation,usingconservativeanalyticalmargins.ThenumberofpartsthatAARhadinspectedwouldnotbesufficienttoshowalikelihoodofpartcracking3consistentwithFAAregulatoryguidelinesforrotatingpartlifelimits.WedidnotchangethisAD.RequestReassessmentofCostImpactAARdisagreesthattheNPRMhasminimalimpactontheircompany.AARstatedthattheircostperflightwouldincreaseandcompanyrevenuewouldbereduced.WeagreethatthisADwillimposeaneconomicimpacttooperators.Howanoperatorabsorbsorpassesonthecostislefttotheoperatortodetermine.WedidnotchangethisAD.ClarificationRequirementsSinceweissuedtheproposedAD,wediscoveredthatASBformattingdiscrepanciesexistduetodocumentationchangesimplementedbyGE.Wechangedparagraphs(e)(2), (e)(3),and(e)(4)toreflectthecorrectSBparagraphnumbers.ConclusionWereviewedtherelevantdataanddeterminedthatairsafetyandthepublicinterestrequireadoptingthisADasproposed.CostsofComplianceWeestimatethatthisADwillaffectabout60enginesinstalledonaircraftofU.S.registry.Theaveragepro-ratedcostofthelife-limitedrotatingpartsis$20,000.Theaveragelaborrateis$85perhour.Basedonthesefigures,weestimatethecostofthisADonU.S.operatorstobe$8,715,000.AuthorityforthisRulemakingTitle49oftheUnitedStatesCodespecifiestheFAA'sauthoritytoissuerulesonaviationsafety.SubtitleI,Section106,describestheauthorityoftheFAAAdministrator.SubtitleVII,AviationPrograms,describesinmoredetailthescopeoftheAgency'sauthority.4WeareissuingthisrulemakingundertheauthoritydescribedinSubtitleVII,PartA,SubpartIII,Section44701,"Generalrequirements."Underthatsection,CongresschargestheFAAwithpromotingsafeflightofcivilaircraftinaircommercebyprescribingregulationsforpractices,methods,andprocedurestheAdministratorfindsnecessaryforsafetyinaircommerce.Thisregulationiswithinthescopeofthatauthoritybecauseitaddressesanunsafeconditionthatislikelytoexistordeveloponproductsidentifiedinthisrulemakingaction.RegulatoryFindingsWehavedeterminedthatthisADwillnothavefederalismimplicationsunderExecutiveOrder13132.ThisADwillnothaveasubstantialdirecteffectontheStates,ontherelationshipbetweenthenationalgovernmentandtheStates,oronthedistributionofpowerandresponsibilitiesamongthevariouslevelsofgovernment.Forthereasonsdiscussedabove,IcertifythatthisAD:(1)Isnota"significantregulatoryaction"underExecutiveOrder12866,(2)Isnota"significantrule"underDOTRegulatoryPoliciesandProcedures(44FR11034,February26,1979),(3)WillnotaffectintrastateaviationinAlaskatotheextentthatitjustifiesmakingaregulatorydistinction,and(4)Willnothaveasignificanteconomicimpact,positiveornegative,onasubstantialnumberofsmallentitiesunderthecriteriaoftheRegulatoryFlexibilityAct.ListofSubjectsin14CFRPart39Airtransportation,Aircraft,Aviation.safety,Incorporationbyreference,Safety.AdoptionoftheAmendmentAccordingly,undertheauthoritydelegatedtomebytheAdministrator,theFAAamends14CFRpart39asfollows:5PART39-AIRWORTIDNESSDIRECTIVES1.Theauthoritycitationforpart39continuestoreadasfollows:Authority:49U.S.C.106(g),40113,44701.§39.13[Amended]2.TheFAAamends§39.13by:a.Removingairworthinessdirectives(AD)2001-18-06,Amendment39-12432(66FR47575,September13,2001)("AD2001-18-06"):andAD2008-22-16,Amendment39-15712(73FR63629,October27,2008)("AD2008-22-16"),andb.AddingthefollowingnewAD:2015-xx-xxGeneralElectricCompany:Amendment39-18xxx;DocketNo.FAA-2008-0808;DirectorateIdentifier2008-NE-18-AD.(a)EffectiveDateThisADiseffective[INSERTDATE35DAYSAFTERDATEOFPUBLICATIONINTHEFEDERALREGISTER].(b)AffectedADsThisADreplacesAD2001-18-06andAD2008-22-16.(c)ApplicabilityThisADappliestoallGeneralElectricCompany(GE)CT58-100-2,CT58-110-l,CT58-110-2,CT58-140-l,andCT58-140-2turboshaftengines.(d)UnsafeConditionThisADwaspromptedbyrecalculationoflifeforpartsinstalledonenginesusedinUtilityoperations,andareducedlifeforcompressorspoolsinalloperations.WeareissuingthisADtopreventfailureoflife-limitedrotatingparts,uncontainedpartrelease,damagetotheengine,anddamagetotheaircraft.(e)ComplianceDotheactionsrequiredbythisAD,unlessalreadydone.6(1)CalculatingCyclicLifeConsumptionRe-calculatethecycles-since-newforallcompressorspools,andforlife-limitedrotatingpartsotherthancompressorspoolsusedinUtilityoperations.Useparagraphs3.A.(l)and3.B.(l)intheAccomplishmentInstructionsofGECT58AlertServiceBulletin(ASB)No.SB72-A0162,Revision16,datedJanuary7,2015,toperformthecalculations.(2)RemovalofCompressorSpoolsAftertheeffectivedateofthisAD,removecompressorspools,partnumbers(PINs)5124T94G02,6010T57G04,6010T57G07,and6010T57G08fromservice,beforereachingthelifelimitsspecifiedinparagraph4.A.,AppendixA,inGECT58ASBNo.SB72-A0162,Revision16,datedJanuary7,2015,asre-calculatedperparagraph(e)(!)ofthisAD.(3)RemovalofRotatingPartsusedinUtilityOperationsotherthanCompressorSpoolsAftertheeffectivedateofthisAD,removefromserviceanylife-limitedrotatingpartusedinUtilityoperations,otherthanthecompressorspoolswithPINslistedinparagraph(e)(2)ofthisAD,thatexceedsitslifelimitasre-calculatedperparagraph(e)(!)ofthisAD.UseTablesI,II,III,andIVinparagraphs3.D.through3.G.intheAccomplishmentInstructionsinGECT58ASBNo.SB72-A0162,Revision16,datedJanuary7,2015,andparagraph4.D.,AppendixAofthisGECT58ASB,todeterminewhentoremovetheseparts.(4)RemovalofRotatingPartsnotusedinUtilityOperationsotherthanCompressorSpoolsAftertheeffectivedateofthisAD,removefromserviceanylife-limitedrotatingpartnotusedinUtilityoperations,otherthanthecompressorspoolswithPINslistedinparagraph(e)(2)ofthisAD,thatexceedsitslifelimit.UseTablesI,II,III,andIVin7paragraphs3.D.through3.G.intheAccomplishmentInstructionsinGECT58ASBNo.SB72-A0162,Revision16,datedJanuary7,2015,andparagraph4.C.,AppendixAofthisGECT58ASB,todeterminewhentoremovetheseparts.(t)AlternativeMethodsofCompliance(AMOCs)TheManager,EngineCertificationOffice,FAA,mayapproveAMOCsforthisAD.Usetheproceduresfoundin14CFR39.19tomakeyourrequest.Youmayemailyourrequestto:ANE-AD-AMOC@faa.gov.(g)RelatedInformationFormoreinformationaboutthisAD,contactChristopherMcGuire,AerospaceEngineer,EngineCertificationOffice,FAA,Engine&PropellerDirectorate,12NewEnglandExecutivePark,Burlington,MA01803;phone:781-238-7120;fax:781-238-7199;email:chris.mcguire@faa.gov.(h)MaterialIncorporatedbyReference(1)TheDirectoroftheFederalRegisterapprovedtheincorporationbyreference(IBR)oftheserviceinformationlistedinthisparagraphunder5U.S.C.552(a)andICFRpart51.(2)YoumustusethisserviceinformationasapplicabletodotheactionsrequiredbythisAD,unlesstheADspecifiesotherwise.(i)GeneralElectricCompany(GE)CT58AlertServiceBulletinNo.SB72-A0162,Revision16,datedJanuary7,2015.(ii)Reserved.(3)ForGEserviceinformationidentifiedinthisAD,contactGeneralElectricCompany,GEAviation,Room285,OneNeumannWay,Cincinnati,OH45215;phone:513-552-3272;email:aviation.fleetsupport@ge.com.8(4)YoumayviewthisserviceinformationatFAA,Engine&PropellerDirectorate,12NewEnglandExecutivePark,Burlington,MA.ForinformationontheavailabilityofthismaterialattheFAA,call781-238-7125.(5)Youmayviewthiss·erviceinformationattheNationalArchivesandRecordsAdministration(NARA).ForinformationontheavailabilityofthismaterialatNARA,call202-741-6030,orgoto:http://www.archives.gov/federal-register/cfr/ibrlocations.html.IssuedinBurlington,Massachusetts,onSeptember30,2015.ColleenM.D'Alessandro,DirectorateManager,Engine&PropellerDirectorate,AircraftCertificationService.9