Proposed Rules. Notice of proposed rulemaking (NPRM)

Agency: Federal Aviation Administration (FAA), DOT
Action: Notice of proposed rulemaking (NPRM)
Citation: FR Doc. 2017-19250 · RIN 2120-AA64 · Docket No. FA-2017-0668; Product Identifier 2017-NE-17-AD · 14 CFR 39

Summary

We propose to adopt a new airworthiness directive (AD) for all General Electric Company (GE) CF6-80A, -80A1, -80A2, and -80A3 turbofan engines. This proposed AD was prompted by high cycle fatigue (HCF) cracking of the low-pressure turbine (LPT) stage 3 nozzles. This proposed AD would require replacement of the LPT stage 3 nozzles. We are proposing this AD to address the unsafe condition on these products.

Dates

We must receive comments on this proposed AD by October 27, 2017.

Supplementary Information

Comments Invited We invite you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2017-0668; Product Identifier 2017-NE-17-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this NPRM. We will consider all comments received by the closing date and may amend this NPRM 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 NPRM. Discussion We received a report of an LPT uncontainment on a CF6-80A2. Investigation determined the uncontainment was the result of HCF cracking of the LPT stage 3 nozzles. This condition, if not corrected, could result in failure of the LPT stage 3 nozzle, damage to the engine, and damage to the airplane. Related Service Information We reviewed GE CF6-80A Service Bulletin (SB) 72-0749, Revision 2, dated August 31, 2016. The SB describes procedures for replacement of the LPT stage 3 nozzles. FAA's Determination We are proposing 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. Proposed AD Requirements This proposed AD would require replacement of the LPT stage 3 nozzles. Costs of Compliance We estimate that this proposed AD affects 7 engines installed on airplanes of U.S. registry. We estimate the following costs to comply with this proposed AD: Estimated Costs Action Labor cost Parts cost Cost per product Cost on U.S. operators Replacement of LPT stage 3 nozzles 0 work-hours × $85 per hour = $0 $368,260 $368,260 $2,577,820 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. 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 determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 this proposed regulation: (1) Is not a “significant regulatory action” under Executive Order 12866, (2) Is not a “significant rule” under the 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. The Proposed Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 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): General Electric Company: Docket No. FAA-2017-0668; Product Identifier 2017-NE-17-AD. (a) Comments Due Date We must receive comments by October 27, 2017. (b) Affected ADs None. (c) Applicability This AD applies to General Electric (GE) CF6-80A, -80A1, -80A2, and -80A3 turbofan engines with low-pressure turbine (LPT) stage 3 nozzles, part number (P/N) 9290M52P05 and 9290M52P06, installed. (d) Subject Joint Aircraft System Component (JASC) Code 7250, Turbine Section. (e) Unsafe Condition This AD was prompted by high cycle fatigue (HCF) cracking of the LPT stage 3 nozzles resulting in LPT uncontainment. We are issuing this AD to prevent cracking of the LPT stage 3 nozzles. The unsafe condition, if not corrected, could result LPT uncontainment, damage to the engine, and damage to the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions Within 36 months after the effective date of this AD, replace LPT stage 3 nozzles, P/N 9290M52P05 and 9290M52P06, with a part eligible for installation. (h) Alternative Methods of Compliance (AMOCs) (1) The Manager, FAA, ECO Branch, Compliance and Airworthiness Division, 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 ECO Branch, send it to the attention of the person identified in paragraph (i)(1) 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. (i) Related Information (1) For more information about this AD, contact Herman Mak, Aerospace Engineer, FAA, ECO Branch, Compliance and Airworthiness Division, 1200 District Avenue, Burlington, MA 01803; phone: 781-238-7147; fax: 781-238-7199; email: herman.mak@faa.gov. (2) GE CF6-80A Service Bulletin 72-0749, Revision 2, dated August 31, 2016; can be obtained from GE using the contact information in paragraph (i)(3) of this AD. (3) For service information identified in this proposed AD, contact General Electric Company, GE-Aviation, Room 285, 1 Neumann Way, Cincinnati, OH 45215, phone: 513-552-3272; fax: 513-552-3329; email: geae.aoc@ge.com. (4) You may view this service information at the FAA, Engine and Propeller Standards Branch, Policy and Innovation Division, 1200 District Avenue, Burlington, MA. For information on the availability of this material at the FAA, call 781-238-7125. Issued in Burlington, Massachusetts, on September 6, 2017. Robert J. Ganley, Manager, Engine and Propeller Standards Branch, Aircraft Certification Service. [FR Doc. 2017-19250 Filed 9-11-17; 8:45 am]