### DEPARTMENT OFTRANSPORTATION FederalAviation Administration 14 CFRPart39 [4910-13-P]

[Docket No. FAA-2015-7491; DirectorateIdentifier2015-NE-39-AD; Amendment 39-18569; AD 2016-13-05] RIN 2120-AA64 Ainvorthiness Directives; GeneralElectric CompanyTurbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. 

### ACTION: Final rule. 

### SUMMARY: We are adopting a new airworthiness directive (AD) for all General Electric Company (GE) GE90-76B, GE90-77B, GE90-85B, GE90-90B, and GE90-94B turbofan engines. This AD was promptedby an uncontained failure ofthe high-pressure compressor (HPC) stage 8-10 spool, leading to an airplane fire. This AD requires eddy current inspection (ECI) orultrasonic inspection (USI) ofthe HPC stage 8-10 spool and removing from service those parts that fail inspection. We are issuing this AD to prevent failure ofthe HPC stage 8-10 spool, uncontained rotorrelease, damage to the engine, and damage to the airplane. 

### DATES: This AD is effective [INSERT DATE 35 DAYS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER]. 

### ADDRESSES: See the ForFurther Information Contact section. 

### Examiningthe AD Docket You may examine the AD docket on the Internet at http:/ /www.regulations.gov by searching for and locating DocketNo. FAA-2015-7491; or inperson at the Docket Management Facilitybetween 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the regulatory evaluation, any comments received, and otherinformation. The address for the Docket Office (phone:800-647-5527) is DocumentManagement Facility, U.S. Department ofTransportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590. FOR FURTHER INFORMATION CONTACT: John Frost, Aerospace Engineer, Engine Certification Office, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-238-7756; fax: 781-238-7199; email:john.frost@faa.gov. SUPPLEMENTARY INFORMATION: Discussion We issued a notice ofproposedrulemaking (NPRM) to amend 14 CFRpart 39 by adding an AD that would apply to all GE GE90-76B, GE90-77B, GE90-85B, GE90-90B, and GE90-94B turbofan engines. The NPRM published in the FederalRegister on January 13, 2016 (81 FR 1582). The NPRM was prompted by an uncontained failure of the HPC stage 8-10 spool, leading to an airplane fire. The NPRM proposed to require ECis orUSIs ofthe HPC stage 8-10 spool and removing from service those parts that fail inspection. We are issuing this AD to prevent failure ofthe HPC stage 8-10 spool, uncontained rotorrelease, damage to the engine, and damage to the airplane. Comments We gave the public the opportunityto participate in developing this AD. The following presents the comments received onthe NPRM (81 FR 1582, January 13, 2016) and the FAA'sresponse to each comment. Support for the NPRM (81 FR 1582, January 13, 2016) The Air Line Pilots Association expressed support for the NPRM (81 FR 1582, January 13, 2016). Request to ChangeApplicability British Airways, United Airlines, and The Boeing Company commentedthat HPC stage 8-10 spool, part numbers (PINs) 1844M90G01 and 1844M90G02 are notrequired

2inthe Applicability paragraph ofthis AD. They notedthat the associated AD 2015-27-01, (81 FR 1291, January 12, 2016) and the precipitating event involved only HPC stage 8-10 spool, 

### PIN 1694M80G04. We disagree. HPC stage 8-10 spool 

### PINs 1844M90G01 and 1844M90G02 are susceptible to the same failure mode as HPC stage 8-10 spool, 

### PIN 1694M80G04. However, we acknowledge that the one-time inspection is not needed for the majority of HPC stage 8-10 spool 

### PINs 1844M90G01 and 1844M90G02. Therefore, we revised paragraph (e)(1) ofthis AD to apply to only specific serial numbers (SINs) of

### PINs 1844M90G01 and 1844M90G02 for the one-time inspection. Request to Change Compliance Time BritishAirways requested that we clarify ifa repetitive on-wing inspection is required. They reasoned that the service information lists the on-wing inspection as one time only. We disagree. Paragraph (e)(1) ofthis AD mandates that specific partsbe inspected priorto a cycle limit. This initial inspectionmay be performed on wing using USI or at shop visit using ECI. Repetitive inspections priorto shop visit are not mandated, however we acknowledge that GE has commentedthat they shouldbe performed. We did not change this AD. Request to Change TerminatingAction GE requested that we remove the repetitive shop visit inspection from the Compliance section ofthis AD and instead mandate that the airworthiness limitations section (ALS) ofthe engine manual include the repetitive inspections. They also requested that the Summary section and Related Information section ofthis AD be revised to reflectthis change. Theyreasoned that this will allow a terminating action for this AD.

3We disagree. Atthis time we do not feel that a changeto the ALS is appropriate

as root cause has notbeen determined. We did not changethis AD. Request to ChangeInstallation Prohibition GE requested that we clarifythat the installationprohibition does not apply to

newparts. They statedthat newparts do not need to be inspectedpriorto installation. The inspections are only applicable to parts that have beenused in service. We agree. Werevised paragraph (f) ofthis AD to specifythat inspections are only required for parts thathave beenused in service. Request to Change Service Information GE and British Airways requested that we revise the Related Service Information paragraph ofthis AD to remove the reference to Engine Manual, Chapter 72-00-31, Special Procedure 007 and add a reference to GE GE90 SB 72-1146. Theyreasoned that the Special Procedure is considered an additional inspectiontechnique and the other inspectionprocedures listedprovide full detection capability ofdefects inthe area of

concern. We disagree. The service information is not incorporated byreference inthis AD and was previously included for informationpurposes only. However, to preclude any confusion onthis point, we removed all service information from the Related Information section ofthis AD. Request to ChangeApplicability GE requested that we reduce the applicability for the initial inspection. GE has determined that an oldermanufacturing process maybe a contributorto part failure and that all parts manufactured using this process should be inspectedpriorto shop visit. We agree. We revisedthe applicability ofthe initial inspectionto include all HPC stage 8-10 spool, 

### PIN 1694M80G04, and specific SINs ofHPC stage 8-10 spool, PINs 1844M90G01 and 1844M90G02, that were manufacturedusing the olderprocess. 4Request to Change Compliance Time GE has requested that the initial USI compliance time be reduced and to add repetitive inspections every 500 cycles until shop visit ECI for the parts manufactured using the oldermanufacturing process noted above. GE has determinedthat the smallest detectable flaw using USI withthe compressorblades installed is largerthan what was used in the prior analysis. We partially agree. We agree that the USI inspection is not as capable as what

was used in the prior analysis. We also agree that a reduced threshold for initial inspection is appropriate. So, we reduced the initial inspectionthreshold in paragraph (e)(1) ofthis AD from 10,500 cycles to 9,000 cycles and removed USI as an option for the inspections inparagraph (e)(2) ofthis AD. We disagree with including the 500 cycle repetitive inspections; however, repetitive inspections would be a considerationfor additional rulemaking. Conclusion We reviewed the relevant data, consideredthe comments received, and determined that air safety and the public interestrequire adopting this AD withthe changes described previously. We have determined that these minor changes:

• Are consistent withthe intentthat was proposed in the NPRM (81 FR 1582, January 13, 2016) for correcting the unsafe condition; and

• Do not add any additional burdenupon the public than was already proposed inthe NPRM (81 FR 1582, January 13, 2016). We also determinedthat these changes will not increase the economic burden on any operator or increase the scope ofthis AD. Interim Action GE is determining the root cause for the unsafe condition identified inthis AD. Once a root cause is identified, we will consider additional rulemaking. 

### 5Costs ofCompliance We estimate that this AD affects 54 engines installed on airplanes ofU.S. registry. We also estimate that it will take about 7hours perengine to comply with this AD. The average laborrate is $85 perhour. We estimate one part will fail inspection at a cost of $780,000. Based onthese figures, we estimate the total cost ofthis AD to U.S. operators to be $812,130. Authority for this Rulemaking Title 49 ofthe United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority ofthe FAA Administrator. Subtitle VII: Aviation Programs, describes in more detail the scope ofthe Agency's authority. We are issuing this rulemaking underthe authority described in Subtitle VII, Part A, Subpart III, Section44701: "Generalrequirements." Underthat section, Congress charges the FAA with promoting safe flight ofcivil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope ofthat authority because it addresses anunsafe condition that is likely to exist ordevelop onproducts identified inthis rulemaking action. Regulatory Findings This AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect onthe States, onthe relationship betweenthe national government and the States, oronthe distribution ofpower and responsibilities among the various levels ofgovernment. For the reasons discussed above, I certify thatthis AD: (1) Is not a "significantregulatory action" under Executive Order 12866,

6(2) Is not a "significantrule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), (3) Will not affect intrastate aviation in Alaska, and (4) Will not have a significant economic impact, positive ornegative, on a substantial number ofsmall entities under the criteria ofthe Regulatory Flexibility Act. List ofSubjects in 14 CFRPart 39 Airtransportation, Aircraft, Aviation safety, Incorporation by reference, Safety. Adoption ofthe Amendment Accordingly, underthe authority delegated to me by the Administrator, the FAA amends 14 CFRpart 39 as follows: PART 39 - AIRWORTHINESS DIRECTIVES 1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. 

### § 39.13 [Amended] 2. The FAA amends§ 39.13 by adding the following new airworthiness directive (AD): 2016-13-05 General Electric Company: Amendment 39-18569; Docket No. FAA-2015-7491; Directorate Identifier 2015-NE-39-AD. (a) Effective Date This AD is effective [INSERT DATE 35 DAYS AFTERDATE OF PUBLICATION IN THE FEDERAL REGISTER]. (b) Affected ADs None. (c) Applicability This AD applies to General Electric Company (GE) GE90-76B, GE90-77B, GE90-85B, GE90-90B, and GE90-94B turbofan engines with a high-pressure compressor 7(HPC) stage 8-10 spool, part numbers (PINs) 1694M80G04, 1844M90G01, or 1844M90G02, installed. (d) Unsafe Condition This AD was prompted by anuncontained failure ofthe HPC stage 8-10 spool. We are issuing this AD to prevent failure ofthe HPC stage 8-10 spool, uncontained rotor release, damage to the engine, and damage to the airplane. (e) Compliance Comply withthis AD withinthe compliance times specified, unless already done. (1) ForHPC stage 8-10 spool, 

### PIN 1694M80G04, all serial numbers (SINs), or HPC stage 8-10 spool, 

### PIN 1844M90G01 or 1844M90G02, with a SIN listed inFigure 1

to paragraph (e) ofthis AD; perform an eddy current inspection (ECI) orultrasonic inspection (USI) ofthe stage 8 aft web upper face, after reaching 8,000 cycles since new (CSN), but, before exceeding 9,000 CSN, orwithin 500 cycles in service after the effective date ofthis AD, whichever occurs later.

8Figure 1 to Paragraph (e)- HPC Stage 8-10 Spool SINs PartNumbers Serial Numbers

1844M90G01 GWNOOSMF GWNBK753 GWNBS077 GWNBS497 GWNBS724 GWNOOSMG GWNBK754 GWNBS078 GWNBS499 GWNBS794 GWN0087M GWNBK841 GWNBS079 GWNBS500 GWNBS810 GWN0087N GWNBK842 GWNBS080 GWNBS501 GWNBS811 GWNOODGK GWNBK843 GWNBS081 GWNBS502 GWNBS812 GWNOODGL GWNBK844 GWNBS157 GWNBS609 GWNBS813 GWNBJ992 GWNBK952 GWNBS158 GWNBS610 GWNBS814 GWNBK667 GWNBK953 GWNBS159 GWNBS611 GWNBS910 GWNBK674 GWNBK954 GWNBS160 GWNBS612 GWNBS911 GWNBK675 GWNBK955 GWNBS266 GWNBS613 GWNBS912 GWNBK743 GWNBK956 GWNBS267 GWNBS614 GWNBS914 GWNBK744 GWNBK957 GWNBS268 GWNBS721 GWNBS915 GWNBK751 GWNBK958 GWNBS269 GWNBS722 GWNBS982 GWNBK752 GWNBK959 GWNBS270 GWNBS723 GWNBS983 1844M90G02 GWNOOC2T GWN01C5N GWN02N8D GWN03RTM GWN04E21 GWNOOC2V GWN01GE2 GWN02T3R GWN03RTP GWN04GHT GWNOOG2N GWN01GE3 GWN02WGM GWN040RL GWN04GHW GWNOOG2P GWN01GE4 GWN0311K GWN040RM GWN04GJO GWNOOPFP GWN01GE6 GWN035PP GWN040RN GWN04JW6 GWNOOPFR GWN01WH1 GWN038TD GWN040RP GWN04JW7 GWNOOT2N GWN02688 GWN039TG GWN04202 GWN04JW8 GWNOOYHV GWN02689 GWN03G2R GWN0435W GWN04L7K GWN0125G GWN0268A GWN03G2W GWN04360 GWN04L7L GWN0125H GWN02DP2 GWN03G30 GWN04361 GWN04MT7 GWN0166K GWN02DP3 GWN03JPC GWN04362 GWN04MT8 GWN01C5K GWN02F9F GWN03JPD GWN04ATG GWNBS984 GWN01C5L GWN02F9G GWN03N8P GWN04ATH GWN01C5M GWN02L9T GWN03N8R GWN04E20 (2) For all HPC stage 8-10 spools, 

### PIN 1694M80G04, 1844M90G01, or 1844M90G02, perform anECI ofthe stage 8 aft web upper face ofthe HPC stage 8-10 spool at each shop visit. (3) Remove from service any HPC stage 8-10 spool that fails the inspection required byparagraphs (e)(1) or (e)(2) ofthis AD, and replace with a spool eligible for installation.

9(f) Installation Prohibition After the effective date ofthis AD, do not re-install into any engine, any HPC stage 8-10 spool, PINs 1694M80G04, 1844M90G01, or 1844M90G02, unless the spool has passed an ECI ofthe stage 8 aft web upper face as specified in paragraph (e)(1) or (e)(2) ofthis AD. (g) Definition Forthe purpose ofthis AD, an engine shop visit is the induction ofan engine into the shop for maintenance during whichthe compressor discharge pressure seal face is exposed. (h) Alternative Methods ofCompliance (AMOCs) The Manager, Engine Certification Office, FAA, may approve AMOCs for this AD. Use the procedures found in 14 CFR 39.19 to make yourrequest. You may email your request to: ANE-AD-AMOC@faa.gov. (i) Related Information Formore information aboutthis AD, contact John Frost, Aerospace Engineer, Engine Certification Office, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-238-7756; fax: 781-238-7199; email:john.frost@faa.gov. (j) Material Incorporated by Reference None. Issued in Burlington, Massachusetts, onJune 15, 2016.

ColleenM. D'Alessandro, Manager, Engine & Propeller Directorate, Aircraft Certification Service.

10