AD 2024-22-05

This AD is effective December 31, 2024.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of December 31, 2024.

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2024-2008; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this final rule, any comments received, and other information. The address for Docket Operations is U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.

Material Incorporated by Reference:

• For material identified in this AD, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; telephone 562-797-1717; website myboeingfleet.com.

• You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195. It is also available at regulations.gov under Docket No. FAA-2024-2008.

Joseph Hodgin, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3962; email: joseph.j.hodgin@faa.gov.

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to all The Boeing Company Model 787-8, 787-9, and 787-10 airplanes. The NPRM published in the Federal Register on August 1, 2024 (89 FR 62685). The NPRM was prompted by a report that during manufacture of drag brace lower lock link assemblies for the MLG, a certain required inspection was not performed. In the NPRM, the FAA proposed to require doing a check of maintenance records or an inspection to determine if certain drag brace lower lock link assemblies are installed, and applicable on-condition actions. The FAA is issuing this AD to address unsafe condition on these products.

The FAA received comments from an individual who supported the NPRM without change.

The FAA received additional comments from three commenters, including Boeing, United Airlines, and American Airlines. The following presents the comments received on the NPRM and the FAA's response to each comment.

American Airlines, United Airlines, and Boeing requested that the affected landing gear drag brace lower lock link assembly part number be corrected from part number 531Z2010-501, to part number 513Z2010-501. American Airlines, United Airlines, and Boeing stated that paragraph (i) of the proposed AD contains a typo for the affected landing gear drag brace lower lock link assembly part number. The commenters stated that the part number listed in the proposed AD is 531Z2010-501, the correct part number is 513Z2010-501. American Airlines stated it reviewed Boeing Alert Requirements Bulletin B787-81205-SB320048-00 RB, Issue 001, dated November 20, 2023, and confirmed that the correct part number is 513Z2010-501. Boeing noted that the part number in the proposed AD does not match Boeing Alert Requirements Bulletin B787-81205-SB320048-00 RB, Issue 001, dated November 20, 2023.

The FAA agrees that the correct affected landing gear drag brace lower lock link assembly part number is 513Z2010-501. The FAA has revised paragraph (i) of this AD to reflect the correct part number.

American Airlines stated that it appears that an airworthiness directive is not necessary as the safety issue is being addressed between Boeing and the affected operator(s) via the alert service bulletin. American Airlines also stated that compliance will require the unnecessary burden at all worldwide operators and MROs ( i.e., certified repair stations) to create safeguards to look for these four serial numbers any time maintenance is performed on the life limited part component of the lock link assembly, the lower lock link assembly itself, the next higher assembly lock link assembly, the next higher assembly drag brace assembly, the next higher level landing gear, and the airplane throughout the remaining life of the entire 787 worldwide fleet. The FAA infers that American Airlines is requesting that the NPRM be withdrawn.

The FAA disagrees with the request to withdraw the NPRM. Operators are not required to accomplish Boeing Alert Requirements Bulletin B787-81205-SB320048-00 RB, Issue 001, dated November 20, 2023, until an AD mandates accomplishment. This AD addresses the identified unsafe condition by mandating the actions in that material, which ensures that the affected (unsafe) parts are removed from the airplanes identified in paragraph (g) of this AD. In addition, due to rotability of the affected parts, the parts installation prohibition specified in paragraph (i) of this AD is the only way to ensure the affected parts are not installed on all airplanes identified in paragraph (c) of this AD. The FAA has not changed this AD in this regard.

The FAA reviewed the relevant data, considered any comments received, and determined that air safety requires adopting this AD as proposed. Accordingly, the FAA is issuing this AD to address the unsafe condition on these products. Except for minor editorial changes, and any other changes described previously, this AD is adopted as proposed in the NPRM. None of the changes will increase the economic burden on any operator.

The FAA reviewed Boeing Alert Requirements Bulletin B787-81205-SB320048-00 RB, Issue 001, dated November 20, 2023. This material specifies procedures for doing a check of maintenance records or an inspection of the drag brace lower lock link assembly on the right and left MLG for affected serial numbers and applicable on-condition actions. On-condition actions include replacing any affected drag brace lower lock link assembly on the MLG with a serviceable drag brace lower lock link assembly.

This material 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.

The FAA estimates that this AD affects 156 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD:

The FAA estimates the following costs to do any necessary replacement that would be required based on the results of the inspection. The agency has no way of determining the number of aircraft that might need this replacement:

The FAA has included all known costs in its cost estimate. According to the manufacturer, however, some or all of the costs of this AD may be covered under warranty, thereby reducing the cost impact on affected operators.

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.

The FAA is 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 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) Will not affect intrastate aviation in Alaska, and

(3) 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 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 adding the following new airworthiness directive: