AnAlenaAeronauiuaandEAI)SjoinicntureARTechnicalDirectorateOfficeofAirworthinessUSDepartmentofTransportationDocketOperations,WestBuildingGroundFloor,RoomWl2-140,1200NewJerseyAvenue,SEWashington,DC20590USA1,alléePierre-Nadot12BlagnacCedex-FranceTel:33562216741Fax:33562216718COPYFAAMrTomRodriguezEASAMrFlorentinoBascunana0/REF:D0/TC2741/10Toulouse,May25t12010SUBJECT:ATR42/72Petitionforexemptionsregarding14CFRsectionsDearSirThispetitionforexemption,submittoFAA,concerns:PART121--OPERATINGREQUIREMENTS:DOMESTIC,FLAG,ANDSUPPLEMENTALOPERATIONS12.AmendSec.121.359byrevisingparagraphs(e)(1)and(j)(1),addingnewparagraph(j)(4),andrevisingparagraph(k)toreadasfollows:Sec.121.359Cockpitvoicerecorders.*****(k)Allairplanesrequiredbythisparttohaveacockpitvoicerecorderandaflightdatarecorder,thatinstalldatalinkcommunicationequipmentonorafterDecember6,2010,mustrecordalldatalinkmessagesasrequiredbythecertificationruleapplicabletotheairplane.13.AmendappendixMtopart121byrevisingfootnote18,toreadasfollows:AppendixMtoPart121--AirplaneFlightRecorderSpecifications*****\18\ForallaircraftmanufacturedonorafterDecember6,2010,thesecondspersamplingintervalis0.125.Eachinputmustberecordedatthisrate.Alternatelysamplinginputs(interleaving)tomeetthissamplingintervalisprohibited.AvionsdeTransportRegional.1,alléePierre-Nadot31712BlagnacCedex-FrancePhone:+33(0)562216221-Fax:÷33(0)562216800-www.atraircraftcomATRconsiderations:Regardingthese2requirementsapplicableonATRaircraftmanufacturedonorafterDecember6,2010,andtakingintoaccountthefollowingdata:-ATRisworkingonmodification5948/NewAvionicsSuite“projectP-EASA.CSV.A01463”,-ATR42-500&72-212AmodelswithCurrentAvionicswillnomorebemanufacturedandwillbegraduallyreplacedbysamemodelsbutwithmodification5948/NASduring2011.-AnsweringthesetwonewrequirementswillhaveaheavyimpactonATRside(technicalandfinancial)todevelopnecessarymodificationsformodelsATR42-500&72-212AwithCurrentAvionics:1.1ModificationofMPC(MultiPurposeComputer),whichacquiresandformatsparametersforSSFDR,tomodifySSFDRoutputframewithnewsamplingrates,12ReplaceofSSFDRbyaSSFDRwithcapabilitytoacquiredataat512wordsbysecond(presentequipmentislimitedto256wordsbysecondacquisition),1.3ModificationofCMU/ACARS(whichisonlyanoption)computertoprovidecapabilitytotransmitdatalinkdata,1.4ReplacementofSSCVRbyaSSCVRhavingdatalinkrecordingcapability,1.5Aircraftwiringmodificationtointerconnectmodifiedequipmenttonewequipmentfordatalinkpurpose.1.6Testsandcertificationofnecessarymodifications(MPC,CMU/ACARS,Wiring).-AnsweringthesetwonewrequirementsisbasicallyplannedindefinitionformodelsATR42-500&72-212AwithNewAvionicsSuite(Mod5948).-TheaircraftdefinitionforATR42-500&72-212AmodelswithCurrentAvionicswillbeidenticaltopresentdefinition,i.e.answeringFAR121.344appendixMrequirements(exceptforfootnote18),andnotdatalinkrecordingwhenACARSinstalledsowithoutanyimpactonsafety.Consideringestimatedtransitionplanforaircraftproductionin2011betweenaircraftwithCurrentandNewAvionics,about30aircraftwillbemanufacturedwithCurrentAvionicSuite.AndasACARSisanoption,nomorethan10aircraftwillbemanufacturedwiththisoption.MoreoverpartoftheseaircraftwillnotflyunderFAAregulation,soestimatedaircraftconcernedflyingunderFAAregulation,orequivalentregulationfollowedbysomeotherforeignAirworthinessAuthorities,tobemanufacturedin2011isbetween5and10aircraftfor“AmendappendixMtopart121byrevisingfootnote18”andlessthan5aircraftfor“Sec.121.359Cockpitvoicerecorders_Datalink”.ATRPosition:ATRposition,regardingtheserequirements,istorequestfromFAAanexemptionforATR42-500&72-212AmodelswithCurrentAvionics,consideringthatofcourseATRwillbasicallycomplywiththesenewrequirementsforATR42-500&72-212AmodelswithNewAvionicsSuiteforwhichtheserequirementshavebeentakenintoaccountinbasicdefinition.Summary(asrequestedinFederalRegulationPart11.81):ATRrequestanexemptionforfollowingrequirements:1-Sec.121.359Cockpitvoicerecorders.(k)Allairplanesrequiredbythisparttohaveacockpitvoicerecorderandaflightdatarecorder,thatinstalldatalinkcommunicationequipmentonorafterDecember6,2010,mustrecordalldatalinkmessagesasrequiredbythecertificationruleapplicabletotheairplane.Page2of32-AppendixMtoPart121--AirplaneFlightRecorderSpecifications*****\18\ForallaircraftmanufacturedonorafterDecember6,2010,thesecondspersamplingintervalis0.125.Eachinputmustberecordedatthisrate.Alternatelysamplinginputs(interleaving)tomeetthissamplingintervalisprohibited.forallATRaircraft42-500&72-212AmodelsfittedwithCurrentAvionicsandmanufacturedonorafterDecember6,2010,duetothefactthatthesemodelswillnomorebemanufacturedandwillbegraduallyreplacedbysamemodelswithmodification5948INASduring2011,andtakingintoaccountthateffortstodevelopnecessarymodificationsarenotinlinewithnumberofaircraftconcerned.Weareatyourdisposalforanyfurtherinformationyoumayneedtoconductyourreview.Yoursfaithfully,RobertTROUILHETAvionicsEngineeringManagerARJeanLouisSOCCOLATROfficeofAirworthinessPage3of3