AD 2019-02-01

We are superseding Airworthiness Directive (AD) 2018-16-07, which applied to certain General Electric Company (GE) GEnx turbofan engines. AD 2018-16-07 required removal and replacement of affected high-pressure turbine (HPT) stator cases (HPT cases). This AD retains those requirements, but reduces certain compliance times. This AD was prompted by the discovery of a quality escape at a manufacturing facility and a determination that the compliance time for the removal and replacement of certain HPT cases must be reduced. We are issuing this AD to address the unsafe condition on these products.

Final rule; request for comments.

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0 1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

Sec. 39.13 [Amended]

0 2. The FAA amends Sec. 39.13 by removing Airworthiness Directive (AD) 2018-16-07, Amendment 39-19347 (83 FR 36724, July 31, 2018), and adding the following new AD:

2019-02-01 General Electric Company: Amendment 39-19548; Docket No. FAA-2019-0042; Product Identifier 2018-NE-25-AD.

(a) Effective Date

This AD is effective February 25, 2019.

(b) Affected ADs

This AD replaces AD 2018-16-07, Amendment 39-19347 (83 FR 36724, July 31, 2018) (``AD 2018-16-07'').

(c) Applicability

This AD applies to General Electric Company (GE) GEnx-1B54, - 1B58, -1B64, -1B67, -1B70, -1B54/P1, -1B58/P1, -1B64/P1, -1B67/P1, - 1B70/P1,-1B54/P2, -1B58/P2, -1B64/P2, -1B67/P2, -1B70/P2, -1B70C/ P1, -1B70/72/P1, -1B70/75/P1, -1B74/75/P1, -1B75/P1, -1B70C/P2, - 1B70/72/P2, -1B70/75/P2, -1B74/75/P2, -1B75/P2, -1B76/P2, -1B76A/P2, -1B78/P2, -2B67, -2B67B, and -2B67/P turbofan engines with a high- pressure turbine (HPT) stator case (HPT case), part number (P/N) 2302M90G04 installed, and with any serial number (S/N) listed in Table 1, 2, or 3, in the Planning Information section of GE Service Bulletin (SB) GEnx-2B S/B 72-0360, Revision 04, dated December 4, 2018, or GE SB GEnx-1B S/B 72-0424, Revision 04, dated December 3, 2018, installed.

(d) Subject

Joint Aircraft System Component (JASC) Code 7250, Turbine section.

(e) Unsafe Condition

This AD was prompted by the discovery of a quality escape at a manufacturing facility involving unapproved rework on HPT cases. We are issuing this AD to prevent failure of the HPT case and subsequent engine fire and damage to the airplane.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done.

(g) Required Actions

(1) For HPT cases listed in Planning Information, Table 1 or 2, of GE SB GEnx-2B S/B 72-0360, Revision 04, dated December 4, 2018, or GE SB GEnx-1B S/B 72-0424, Revision 04, dated December 3, 2018, determine the lesser of the following: Cycles since new (CSN) or cycles since Class A fluorescent penetrant inspection (CSFPI) of the entire HPT case.
(2) Using the determination made in paragraph (g)(1) of this AD, remove from service the HPT case before exceeding the applicable cycles in service accrued after August 15, 2018, the effective date of AD 2018-16-07, as specified in Table 1 to paragraph (g)(2) of this AD. Replace the removed HPT case with a part eligible for installation. [GRAPHIC] [TIFF OMITTED] TR08FE19.001

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(3) For HPT cases listed in Planning Information, Table 3, of GE SB GEnx-2B S/B 72-0360, Revision 04, dated December 4, 2018, determine the lesser of the following: CSN or CSFPI of the entire HPT case.
(4) Using the determination made in paragraph (g)(3) of this AD, remove from service the HPT case before exceeding the cycles in service specified in Table 2 to paragraph (g)(4) of this AD. Replace the removed HPT case with a part eligible for installation. [GRAPHIC] [TIFF OMITTED] TR08FE19.002

(5) For HPT cases listed in Planning Information, Table 3, of GE SB GEnx-1B S/B 72-0424, Revision 04, dated December 3, 2018, determine the lesser of the following: CSN or CSFPI of the entire HPT case.
(6) Using the determination made in paragraph (g)(5) of this AD, remove from service the HPT case before exceeding the cycles in service specified in Table 3 to paragraph (g)(6) of this AD. Replace the removed HPT case with a part eligible for installation. [GRAPHIC] [TIFF OMITTED] TR08FE19.003

(h) Installation Prohibition

After the effective date of this AD, do not install any affected HPT case ontoany engine if the HPT case has been disassembled to piece-part level. Affected HPT cases are identified in paragraphs (g)(1), (g)(3), and (g)(5) of this AD. Piece-part level is defined as when the part is completely disassembled.

(i) Alternative Methods of Compliance (AMOCs)

(1) The Manager, ECO Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the certification office, send it to the attention of the person identified in paragraph (j) of this AD. You may email your request to ANE-AD-AMOC@faa.gov.
(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.

(j) Related Information

For more information about this AD, contact Herman Mak, Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-238-7147; fax: 781-238-7199; email: herman.mak@faa.gov.

(k) Material Incorporated by Reference

(1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) You must use this service information as applicable to do the actions required by this AD, unless the AD specifies otherwise.
(i) General Electric Company (GE) Service Bulletin (SB) GEnx-2B S/B 72-0360, Revision 04, dated December 4, 2018.
(ii) GE SB GEnx-1B S/B 72-0424, Revision 04, dated December 3, 2018.
(3) For GE service information identified in this AD, contact General Electric Company, GE Aviation, Room 285, 1 Neumann Way, Cincinnati, OH 45215; phone: 513-552-3272; email: aviation.fleetsupport@ge.com.
(4) You may view this service information at the FAA, Engine and Propeller Standards Branch, 1200 District Avenue, Burlington, MA. For information on the availability of this material at the FAA, call 781-238-7759.
(5) You may view this service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

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Discussion

We issued AD 2018-16-07, Amendment 39-19347 (83 FR 36724, July 31, 2018) (``AD 2018-16-07''), for certain GE GEnx-1B54, -1B58, -1B64, - 1B67, -1B70, -1B54/P1, -1B58/P1, -1B64/P1, -1B67/P1, -1B70/P1, -1B54/ P2, -1B58/P2, -1B64/P2, -1B67/P2, -1B70/P2, -1B70C/P1, -1B70/72/P1, - 1B70/75/P1, -1B74/75/P1, -1B75/P1, -1B70C/P2, -1B70/72/P2, -1B70/75/P2, -1B74/75/P2, -1B75/P2, -1B76/P2, -1B76A/P2, -1B78/P2, -2B67, -2B67B, and -2B67/P turbofan engines. AD 2018-16-07 required removal of affected HPT cases from service and their replacement with a part eligible for installation. AD 2018-16-07 was prompted by the discovery of a quality escape at a manufacturing facility involving unapproved reworks on HPT cases. We issued AD 2018-16-07 to address failure of the HPT case, which could result in engine fire and damage to the airplane.

Actions Since AD 2018-16-07 was Issued

Since we issued AD 2018-16-07, we have received new data from the manufacturer and have determined that certain HPT cases may have a reduced fatigue life than previously determined. Because of this reduced fatigue life, the HPT cases must be removed and replaced at reduced compliance times. Failure to remove and replace the HPT cases within the reduced compliance times could result in failure of the HPT case resulting in the unsafe condition identified above.

Related Service Information Under 1 CFR Part 51

We reviewed GE Service Bulletin (SB) GEnx-2B S/B 72-0360, Revision 04, dated December 4, 2018, and GE SB GEnx-1B S/B 72-0424, Revision 04, dated December 3, 2018. This service information describes procedures for removing the affected HPT cases from the engine. GE SB GEnx-1B S/B 72-0424 is effective for GEnx-1B engines with the serial numbers of HPT cases listed therein. GE SB GEnx-2B S/B 72-0360 is effective for GEnx- 2B engines with the serial numbers of HPT cases listed therein. This service information is reasonably available because theinterested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

Other Related Service Information

We reviewed Inspection 001, Subtask 72-52-01-230-001, of GEnx-1B Cleaning, Inspection, and Repair Manual GEK112862, Rev 27, dated April 30, 2018, and GEnx-2B Cleaning, Inspection, and Repair Manual GEK114120, Rev 20, dated April 30, 2018. These manuals provide guidance for conducting Class A fluorescent penetrant inspections.

FAA's Determination

We are issuing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.

AD Requirements

This AD requires removal of the affected HPT cases from service and their replacement with a part eligible for installation.

FAA's Justification and Determination of the Effective Date

An unsafe condition exists that requires the immediate adoption of this AD without providing an opportunity for public comments prior to adoption. The FAA has found that the risk to the flying public justifies waiving notice and comment prior to adoption of this rule because of a quality escape at a manufacturing facility involving unapproved rework on HPT cases, which could result in failure of the HPT case and subsequent engine fire and damage to the airplane. Additionally, the compliance time for the required action is shorter than the time necessary for the public to comment and for publication of the final rule. Therefore, we find good cause that notice and opportunity for prior public comment are impracticable. In addition, for the reasons stated above, we find that good cause exists for making this amendment effective in less than 30 days.

Comments Invited

This AD is a final rule that involves requirements affecting flight safety and was not preceded by notice and an opportunity for public comment. However, we invite you to send any written data, views, or arguments about this final rule. Send your comments to an address listed under the ADDRESSES section. Include the docket number FAA-2019- 0042 and Product Identifier 2018-NE-25-AD at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this final rule. We will consider all comments received by the closing date and may amend this final rule because of those comments.
We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this final rule.

Costs of Compliance

We estimate that this AD affects 7 engines installed on airplanes of U.S. registry. We estimate the following costs to comply with this AD:

Estimated Costs ----------------------------------------------------------------------------------------------------------------
Cost per Cost on U.S.
Action Labor cost Parts cost product operators ---------------------------------------------------------------------------------------------------------------- Removal and replacement of HPT cases 0 work-hours x $85 per $362,400 $362,400 $2,536,800
hour = $0. ----------------------------------------------------------------------------------------------------------------

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

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We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, ``General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil 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 of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.
This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to engines, propellers, and associated appliances to the Manager, Engine and Propeller Standards Branch, Policy and Innovation Division.

Regulatory Findings

We have determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.
For the reasons discussed above, I certify that this AD:
(1) Is not a ``significant regulatory action'' under Executive Order 12866,
(2) Is not a ``significant rule'' 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 or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.