AD 2018-26-01

This AD is effective January 10, 2019.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of January 10, 2019.

The Director of the Federal Register approved the incorporation by reference of certain other publications listed in this AD as of May 14, 2018 (83 FR 19176, May 2, 2018).

We must receive any comments on this AD by February 11, 2019.

You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.

• Fax: 202-493-2251.

• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC, 20590.

• Hand Delivery: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC, 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this final rule, contact CFM International Inc., Aviation Operations Center, 1 Neumann Way, M/D Room 285, Cincinnati, OH, 45125; phone: 877-432-3272; fax: 877-432-3329; email: aviation.fleetsupport@ge.com. You may view this service information at the FAA, Engine and Propeller Standards Branch, 1200 District Avenue, Burlington, MA, 01803. For information on the availability of this material at the FAA, call 781-238-7759. It is also available on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2018-1039.

Christopher McGuire, Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA, 01803; phone: 781-238-7120; fax: 781-238-7199; email: chris.mcguire@faa.gov.

We issued AD 2018-18-01, Amendment 39-19380 (83 FR 49272, October 1, 2018), (“AD 2018-18-01”), for all CFM model CFM56-7B turbofan engines. AD 2018-18-01 required initial and repetitive ultrasonic inspections (USI) or eddy current inspection (ECI) of certain fan blades and, if they fail the inspection, their replacement with parts eligible for installation. AD 2018-18-01 resulted from analysis by the manufacturer that indicated a need to reduce the repetitive fan blade inspection interval based on ongoing root cause investigation of an April 2018 engine failure. The April 2018 engine failure was the result of a fractured fan blade leading to the engine inlet cowl disintegrating and debris penetrating the fuselage, causing a loss of pressurization and prompting an emergency descent. One passenger fatality occurred as a result. We issued AD 2018-18-01 to reduce the repetitive inspection interval from 3,000 cycles to 1,600 cycles.

Since we issued AD 2018-18-01, CFM gained a better understanding of the fan blade failures based on the inspections and further analysis of the detected cracks and the April 2018 event. As a result, CFM has published CFM International Service Bulletin (SB) CFM56-7B S/B 72-1033, Revision 3, dated November 6, 2018, to reduce the initial inspection requirement from 20,000 cycles since new (CSN) to 17,000 CSN. We are issuing this AD to address the unsafe condition on these products.

We reviewed CFM International SB CFM56-7B S/B 72-1033, Revision 3, dated November 6, 2018, and Subtask 72-21-01-220-091, of Task 72-21-01-200-001, from the CFM56-7B Engine Shop Manual (ESM), Revision 57, dated January 15, 2018. CFM International SB CFM56-7B S/B 72-1033, Revision 3, describes procedures for performing a USI of the affected fan blades. Subtask 72-21-01-220-091, of Task 72-21-01-200-001, from the CFM56-7B ESM, describes procedures for performing an ECI of the affected fan blades. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

We also reviewed CFM SB CFM56-7B S/B 72-1019, dated March 24, 2017; CFM SB CFM56-7B S/B 72-1019, Revision 1, dated June 13, 2017; CFM SB CFM56-7B S/B 72-1024, dated July 26, 2017; CFM International SB CFM56-7B S/B 72-1033, Revision 2, dated July 27, 2018; CFM SB CFM56-7B S/B 72-1033, Revision 1, dated May 9, 2018; CFM SB CFM56-7B S/B 72-1033, dated April 20, 2018; and General Electric Field Support Technology (FST) Procedure 2370, dated December 9, 2016. These SBs and the FST provide information on performing the USI.

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.

This AD requires initial and repetitive USI or ECI of certain fan blades and, if they fail the inspection, their replacement with parts eligible for installation.

We consider this AD interim action. An investigation to determine the cause of the failure is ongoing, and we may consider additional rulemaking if final action is identified.

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. Due to the reduction in the initial inspection interval, some fan blades have reached or exceeded the revised initial inspection threshold and will require inspection within 1,000 cycles after the effective date of this AD. Because of this, the compliance time for the required action is shorter than the time necessary for the public to comment and for the FAA to issue the final rule to ensure the unsafe condition is addressed. 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.

This AD is a final rule that involves requirements affecting flight safety, and we did not provide you with notice and an opportunity to provide your comments before it becomes effective. 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-2018-1039 and product identifier 2018-NE-14-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.

We estimate that this AD affects 3,716 engines installed on 1,858 airplanes of U.S. registry.

We estimate the following costs to comply with this AD:

We estimate the following costs to complete any necessary replacement of a single fan blade that would be required based on the results of the inspection. We have no way of determining the number of engines that might need fan blades to be replaced.

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.

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.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

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

2. The FAA amends § 39.13 by removing Airworthiness Directive (AD) 2018-18-01, Amendment 39-19380 (83 FR 49272, October 1, 2018) and adding the following new AD: