# D

E PARTME

N

T OF TRANSPORTATIO

N Fed

e

r

a

l A

v

i a tion

A dministration 14

C FR Part

39

[4910-13-P] 

# I Docket

No

. F AA-20 13-0072

; Directorate

Identifier

20 13-N

E -04-AD

; Amendment 39

- 18017

; AD 2014-23-01] RIN 2120-AA64 A irw

o rthine

ss Directives

; Pratt

& Whitne

y Divi

s ion

T urbof

a n

E ngine

s A GE

N CY: 

# Federal Aviation Administration

( F AA),

DOT. ACT

IO

N: 

# Final

rule. SU MMARY

: 

# We

are superseding airworthiness

directive

(AD) 2013-15-09

for

all Pratt 

# & Whitney

Division

(PW)

P W4074, PW4074D,

PW4077, PW4077D,

PW4084D, PW4090,

and PW4090-3

turbofan

engine

mode

l s with certain second-stage

high-p

r essure turbine

(HPT)

air seals installed.

A

D 2013-15-09

required

initial

and repetitive i n spections

for cracks

in second-stage

HPT

air seals.

This

new

AD expands

the applicab

i lity

of

A

D 2013-15

- 09

to include additional

part numbers

(PINs),

r equires remova

l of the

mat

i ng hardware

if

t h

e second-stage

HPT

air seal

is found

with

athroughcrack,

and adds

a mandatory

term

i nating

action.

This

AD

was prompted

by reports

of cracking

in the original

location

on two additional

PINs

and reports

of through-cracks

in

a new location

in the second-stage

HPT

air seal.

We

are issuing

this

AD

to prevent

failure of the second-stage

HPT

air seal, which

could

lead

to uncontained

engine

failure

and damage

to the airplane. DATES:



# This

AD

is effective

[on December

26, 2014). The Director

of the Federal

Register approved

the incorporation

by reference

of

a certa

in publication

listed

in this

AD

as

of September

17,2013

(78

FR 49111,

August

13, 2013

).TheDirectoroftheFederalRegisterapprovedtheincorporationbyreferenceofacertainpublicationlistedinthisADasofSeptember17,2013(78FR49111,August13,2013).ADDRESSES:ForserviceinformationidentifiedinthisAD,contactPratt&WhitneyDivision,400MainSt.,EastHartford,CT06108;phone:(860)565-8770;fax:(860)565-4503.YoumayviewthisserviceinformationattheFAA,Engine&PropellerDirectorate,12NewEnglandExecutivePark,Burlington,MA.ForinformationontheavailabilityofthismaterialattheFAA,call(781)238-7125.ExaminingtheADDocketYoumayexaminetheADdocketontheInternetathttp://www.regulations.govbysearchingforandlocatingDocketNo.FAA-2013-0072;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:Jo-AnnTheriault,AerospaceEngineer,EngineCertificationOffice,FAA,Engine&PropellerDirectorate,12NewEnglandExecutivePark,Burlington,MA01803;phone:781-238-7105;fax:781-238-7199;email:jo-ann.theriault@faa.gov.SUPPLEMENTARYINFORMATION:DiscussionWeissuedanoticeofproposedrulemaking(NPRM)toamend14CFRpart39tosupersedeAD2013-15-09,Amendment39-17525(78FR49111,August13,2013),("AD2013-15-09").AD2013-15-09appliedtoallPWPW4074,PW4074D,PW4077,2PW4077D,PW4084D,PW4090,andPW4090-3turbofanenginemodelswithcertainsecond-stageHPTairsealsinstalled.TheNPRMpublishedintheFederalRegisteronJune5,2014(79FR32500).TheNPRMwaspromptedbyreportsofthrough-cracksinadifferentlocationonasecond-stageHPTairseal,andreportsofcrackingintheoriginallocationintwoadditionalsecond-stageHPTairseals.Pratt&Whitneydevelopedaredesignedsecond-stageHPTairsealthatcorrectsthecrackingconditioninbothlocations.TheNPRMproposedtorequireinitialandrepetitiveinspectionsforcracksinanexpandedpopulationofsecond-stageHPTairseals,andremovalofair sealsthatfailinspection.TheNPRMalsoproposedtorequireremovalofthematinghardwareifthesecond-stageHPTairsealisfoundwithathrough-crack,andamandatoryterminatingactiontotherepetitiveinspectionrequirements.WeareissuingthisADtocorrecttheunsafeconditionontheseproducts.CommentsWegavethepublictheopportunitytoparticipateindevelopingthisAD.ThefollowingpresentsthecommentsreceivedontheNPRM(79FR32500,June5,2014)andtheFAA'sresponsetoeachcomment.RequesttoCorrectPINAllNipponAirways(ANA),JapanAirlines,UnitedAirlines(UA),andPWrequestedthatwecorrectthereferenceintheNPRM(79FR32500,June5,2014)tothePINforthesecond-stageHPTairsealfrom50L041to54L041.Weagree.Wecorrectedthereferencetothesecond-stageHPTairsealPINinthisAD.3RequesttoIncludeAirSealDetailPINUArequestedthatweincludethePINfortheairsealdetailinthisAD.UAhasobservedinstanceswheretheairsealdetail,PIN54L043,isshownasthePINforthesecond-stageHPTairseal.Wedisagree.Thesecond-stageHPTairsealisidentifiedasPIN541041.Itincludesairsealdetail,PIN54L043.ThisADappliestotheentiresecond-stageHPTairseal,includingallofitsdetails.WedidnotchangethisAD.RequesttoChangeComplianceTimeANA,PW,andUArequestedthatthecomplianceintervalinparagraph(e)(2)(i)oftheNPRM(79FR32500,June5,2014)beincreasedfrom100cycles-in-service(CIS)to1,000CIS.ThecommentersindicatedthatthisADshouldbeconsistentwithAD2013-15-09,whichspecifiesthattheeddycurrentinspection(ECI)orinitialfluorescentpenetrantinspection(FPI)shouldbeperformedwithinI,000cyclesaftertheeffectivedateoftheAD.Weagree.PerforminganECIorinitialFPIwithin1,000cyclesofSeptember17,2013,theeffectivedateofAD2013-15-09,maintainsanacceptablelevelofsafety.Wechangedparagraph(e)(2)(i)ofthisADtoread:"Performaninitialeddycurrentinspection(ECI)forcrackswithin1,000cycles-in-serviceafterSeptember17,2013,orbeforefurtherflight,whicheveroccurslater."RequesttoUpdateServiceInformationANAandPWaskedthatweupdatethereferencetotheserviceinformationfromPWServiceBulletin(SB)No.PW4G-112-A72-332,Revision2,datedApril9,2014,toPWSBNo.PW4G-112-A72-332,Revision3,datedJune25,2014.Weagree.WeupdatedtheserviceinformationreferenceintheRelatedInformationparagraphinthisADtoreflectthemostcurrentrevisionofSBNo.PW4G112-A72-332.4RequesttoIncludeFirst-StageHPTAirSealsANArequestedthatfirst-stageHPTairsealsbeaddedtothelistofpartsthatmustberemovedinparagraph(e)(l)(iii)ofthisAD.ANAindicatedthatfirst-stageHPTairsealsareincludedintheTableofPartsinPWSBNo.PW4G-112-72-332.ThisSBlistspartsthatmustberemovedfromserviceifacircumferentialcrackofanylengthisfoundpropagatedthroughtheweboftheforwardflangeouterdiameterofthesecond-stageHPTairseal.Wedisagree.Ifacrackisfoundinthesecond-stageHPTairseal,thenthelifeofmatinghardwareisadverselyaffectedtothepointthatthematinghardwaremustberemoved.Thefirst-stageHPTairsealisnotalife-limitedpartlikethematinghardwarewerequiretoberemovedifacrackisfound.Thefirst-stageHPTairseal,therefore,mayberetainedunlessitisfounddamagedinthecourseofremovingtherestofthematinghardware.Wedidnotchangethis AD.RequesttoDevelopTrackingProcessforPartsBeingRemovedfromServiceUArequestedthatthisADconsiderrecord-keepingfortheresultsoftheFPIforsecond-stageHPTairsealsthatarebeingremovedfromservice.UAcommentedthatinspectingpartsbeingremovedfromserviceisnotcommonpracticeandthattheburdenofshowingcompliancetothisADrestswiththeoperatorandappropriatepaperrecordsneedtobemaintained.WhilethecommenterdidnotrequestaspecificchangetothisAD,weregardthecommentasareferencetothelackofastandardindustrypracticeforinspectingpartsthatarebeingremovedfromservice.Thisreferstothesecond-stageHPTairseals,PIN54L041,whicharesubjecttoanFPIafterremovalfromservice.Wepartiallyagree.Weagreethatinspectingpartsremovedfromservicefortheirimpactonotherpartsisnotcommonpractice.However,operatorsmustmaintainadequaterecordsofthemaintenancetheyperformtoshowthattheproducthasbeenproperlymaintainedandiseligibleforreturntoserviceasairworthy.Wedisagreethatweneedtoimposeadditionalrecordkeepingrequirementsonoperatorstoensurethatthey5complywiththeirobligationtoperformmaintenanceproperly.Itisuptoeachoperatortoestablishitsownrecord-keepingprocess.WedidnotchangethisAD.RequesttoDevelopReportingandTrackingProcessesforSparePartsUAindicatedtheneedforaprocedurefordeterminingtheserviceabilityofspareparts,i.e.,first-stageHPThubs,second-stageHPThubs,andsecond-stageHPTbladeretainingplates,thatmayhavebeenmatedpreviouslytoacrackedsecond-stageHPTairseal.UAnotedthatthecontinuedserviceabilityofthesesparepartsdependsontheresultoftheinspectionofthesecond-stageHPTairsealthatthepartswerematedtowhileinservice.UAwouldlikeproceduresestablishedtoidentify,tag,andmarkthesespareparts.UAnotedthatsuchproceduresarenotstandardizedwithinindustry.UAalsosuggestedthatPWSBNo.PW4G-112-A72-330berevisedtoaddsomekindofmarkingtonotateserviceablespareparts.Wepartiallyagree.Wedonotfindtheneedtomandateaproceduretotrackthesespareparts.Eachoperatorshouldestablishitsownprocessfortrackingitsspareparts.WedidnotchangethisAD.Weagree,however,thatmatinghardwarepreviouslyinstalledwithcrackedsecond-stageHPTairsealsisnoteligibleforinstallationasairworthy.WechangedthisADtoestablishaninstallationprohibitiontoclarifythatlife-limitedpartspreviouslymatedtoacrackedsecond-stageHPTairseal,PIN54L041,cannotbereinstalled.WeaddedInstallationProhibitionparagraph(f)(2)tothisAD,whichstates:"AftertheeffectivedateofthisAD,donotinstallanysparefirst-stageHPThub,second-stageHPThub,orsecond-stageHPTbladeretainingplatethatwaspreviouslymatedinservicetoasecond-stageHPTairseal,PIN54L041,thatwasfoundtohaveathrough-crackinthefrontforwardfilletradius,intoanyengine."6RequesttoClarifyECIRequirementANAaskedthatweclarifytherequirementforanon-wingECIofsecond-stageHPTairseals,PINs50L960and50L976.TheNPRM(79FR32500,June5,2014)proposedanon-wingECIforsecond-stageHPTairseal,PIN54L041,only.Wedisagree.WearenotrequiringanECIforsecond-stageHPTairseals,PINs50L960and50L976,becausetheECIprobeisnotcompatiblewiththegeometryofthosePINs.Also,removalofthesepartsatthenextpiece-partexposurewithoutinteriminspectionsmaintainsanacceptablelevelofsafety.WedidnotchangethisAD.AgreementwiththisADTheBoeingCompanyexpressedsupportfortheNPRM(79FR32500,June5,2014)asproposed.ConclusionWereviewedtherelevantdata,consideredthecommentsreceived,anddeterminedthatairsafetyandthepublicinterestrequireadoptingthisADwiththechangesdescribedpreviously.WealsodeterminedthatthesechangeswillnotincreasetheeconomicburdenonanyoperatororincreasethescopeofthisAD.CostsofComplianceWeestimatethatthisADaffects116enginesinstalledonairplanesofU.S.registry.Wealsoestimatethatitwilltakeabout5hourstoperformtheinspectionrequiredbythisAD.Theaveragelaborrateis$85perhour.Weestimatethattwoengineswillalsorequireremovalofthefirst-stageHPThub,second-stageHPThub,andsecondstageHPTbladeretainingplate.Weestimatethatpartswillcostabout$698,920perengine.Basedonthesefigures,weestimatethetotalcostofthisADonU.S.operatorstobe$23,420,020.7AuthorityforthisRulemakingTitle49oftheUnitedStatesCodespecifiestheFAA'sauthoritytoissuerulesonaviationsafety.SubtitleI,Section106,describestheauthorityoftheFAAAdministrator.SubtitleVII,AviationPrograms,describesinmoredetailthescopeoftheAgency'sauthority.WeareissuingthisrulemakingundertheauthoritydescribedinSubtitleVII,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,Aviationsafety,Incorporationbyreference,Safety.8AdoptionoftheAmendmentAccordingly,undertheauthoritydelegatedtomebytheAdministrator,theFAAamends14CFRpart39asfollows:PART39-AIRWORTHINESSDIRECTIVES1.Theauthoritycitationforpart39continuestoreadasfollows:Authority:49U.S.C.106(g),40113,44701.§39.13[Amended]2.TheFAAamends§39.13byremovingAirworthinessDirective(AD)2013-15-09,Amendment39-17525(78FR49111,August13,2013),andaddingthefollowingnewAD:****-**->"'Pratt&WhitneyDivision:Amendment39-**;DocketNo.FAA-2013-0072;DirectorateIdentifier2013-NE-04-AD.(a)EffectiveDateThisADiseffective[INSERTDATE35DAYSAFTERDATEOFPUBLICATIONINTHEFEDERALREGISTER].(b)AffectedADsThisADsupersedesAD2013-15-09,Amendment39-17525(78FR49111,August13,2013).(c)ApplicabilityThisADappliestoallPratt&WhitneyDivision(PW)PW4074,PW4074D,PW4077,PW4077D,PW4084D,PW4090,andPW4090-3turbofanenginemodelswithsecond-stagehigh-pressureturbine(HPT)airseal,partnumber(PIN)54L041,50L960,or50L976,installed.9(d)UnsafeConditionThisADwaspromptedbyadditionalreportsofcrackinginthesecond-stageHPTairseal.WeareissuingthisADtopreventfailureofthesecond-stageHPTairseal,whichcouldleadtouncontainedenginefailureanddamagetotheairplane.(e)ComplianceComplywiththisADwithinthecompliancetimesspecified,unlessalreadydone.(1)Atthenextpiece-partexposureaftertheeffectivedateofthisAD,dothefollowing:(i)Removefromservicesecond-stageHPTairseals,PINs50L960,50L976,and54L041.(ii)Performafluorescent-penetrantinspection(FPI)ofthesecond-stageHPTairseal,PIN54L041,forathrough-crackinthefrontforwardfilletradius.(iii)Ifathrough-crackinthefrontforwardfilletradiusisfound,removethefirststageHPThub,second-stageHPThub,andsecond-stageHPTbladeretainingplatefromservice.Donotreinstallthefirst-stageHPThub,second-stageHPThub,orsecond-stageHPTbladeretainingplateintoanyengine.(2)Forengineswithsecond-stageHPTairseals,PIN54L041,installed,performinitialandrepetitiveinspectionsforcrackson-winguntilthepartisremovedfromtheengineasfollows:(i)Performaninitialeddycurrentinspection(ECI)forcrackswithin1,000cycles-in-serviceafterSeptember17,2013,orbeforefurtherflight,whicheveroccurslater.(ii)Thereafter,repeattheECIevery1,200cyclessincelastinspection,orfewer,dependingontheresultsoftheinspection.(iii)Usesection4.0oftheappendixofPWAlertServiceBulletin(ASB)No.PW4G-112-A72-330,Revision2,datedJuly11,2013,toperformtheinspectionanduse10(i) Alternative MethodsofCompliance(AMOCs)TheManager,EngineCertificationOffice,FAA,mayapproveAMOCsforthisAD.Usetheproceduresfoundin14CFR39.19tomakeyourrequest.Youmayemailyourrequestto:ANE-AD-AMOC@faa.gov.(j)RelatedInformation(1)FormoreinformationaboutthisAD,contactJo-AnnTheriault,AerospaceEngineer,EngineCertificationOffice,FAA,Engine&PropellerDirectorate,12NewEnglandExecutivePark,Burlington,MA01803;phone:781-238-7105;fax:781-238-7199;email:jo-ann.theriault@faa.gov.(2)PWServiceBulletin(SB)No.PW4G-112-72-332,Revision3,datedJune25,2014,whichisnotincorporatedbyreferenceinthisAD,canbeobtainedfromPW,usingthecontactinformationinparagraph(k)(3)ofthisAD.ThisSBprovidesguidanceonhowtoreplacethesecond-stageHPTairsealwithanairsealthatismoreresistanttolowcyclefatiguecracks.(k)MaterialIncorporatedbyReference(I)TheDirectoroftheFederalRegisterapprovedtheincorporationbyreference(TBR)oftheserviceinformationlistedinthisparagraphunder5U.S.C.552(a)andICFRpart51.(2)YoumustusethisserviceinformationasapplicabletodotheactionsrequiredbythisAD,unlesstheADspecifiesotherwise.(3)ThefollowingserviceinformationwasapprovedforIBRonSeptember17,2013(78FR49111,August13,2013).(i)Pratt&Whitney(PW)AlertServiceBulletinNo.PW4G-112-A72-330,Revision2,datedJuly11,2013.(ii)Reserved.12(4)ForPWserviceinformationidentifiedinthisAD,contactPratt&WhitneyDivision,400MainSt.,EastHartford,CT06108;phone:860-565-8770;fax:860-565-4503.(5)YoumayviewthisserviceinformationatFAA,Engine&PropellerDirectorate,12NewEnglandExecutivePark,Burlington,MA.ForinformationontheavailabilityofthismaterialattheFAA,call781-238-7125.(6)YoumayviewthisserviceinformationattheNationalArchivesandRecordsAdministration(NARA).ForinformationontheavailabilityofthismaterialatNARA,call202-741-6030,orgoto:http://www.archives.gov/federal-register/cfr/ibrlocations.html.IssuedinBurlington,Massachusetts,onOctober30,2014.CJJ/ltV'-Y)ll,DiJJJ!_/fA!ltAkColleenM.D'Alessandro,AssistantDirectorateManager,Engine&PropellerDirectorate,AircraftCertificationService.13