AD 2024-18-08

This AD is effective November 15, 2024.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of November 15, 2024.

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2024-1693; 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 Boeing 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-2024-1693.

Julie Linn, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3584; email: julie.linn@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 certain The Boeing Company Model 737-300, -400, and -800 series airplanes. The NPRM published in the Federal Register on June 24, 2024 (89 FR 52408). The NPRM was prompted by a report that the protective spiral wrap used on certain galley wire bundles does not have the correct flammability properties and may not self-extinguish. In the NPRM, the FAA proposed to require inspecting certain galleys to determine part numbers, inspecting for an existing galley modification placard and marking on galleys with affected part numbers, and replacing wire bundle spiral wrap sleeving as applicable; and to prohibit the installation of affected parts. The FAA is issuing this AD to address the incorrect flammability properties, which, if not addressed, could result in electrical arcing or sparking, ignition of the spiral wire wrapping, and smoke and/or fire in the flight compartment, leading to loss of continued safe flight and landing.

The FAA received comments from the Air Line Pilots Association, who supported the NPRM without change.

The FAA received additional comments from Aviation Partners Boeing. The following presents the comments received on the NPRM and the FAA's response to each comment.

Aviation Partners Boeing stated that the installation of winglets per Supplemental Type Certificate (STC) ST00830SE and STC ST01219SE does not affect the accomplishment of the manufacturer's service instructions.

The FAA agrees with the commenter that STC ST00830SE and STC ST01219SE do not affect the accomplishment of the manufacturer's service instructions. Therefore, the installation of STC ST00830SE and STC ST01219SE does not affect the ability to accomplish the actions required by 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, 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 737-25A1873 RB, dated August 25, 2023; and Boeing Alert Requirements Bulletin 737-25A1876 RB, dated September 1, 2023. This material specifies procedures for an inspection or records check to determine the part number of certain galleys; and for any galley with an affected part number found, an inspection for an existing galley modification placard and any marking indicating the galley was modified using certain service information; and, if applicable, replacement of wire bundle polyethylene protective spiral wrap protective sleeving with Boeing Material Specification (BMS) 13-81 wire protective sleeving. These documents are distinct since they apply to different airplane models.

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 4 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 inspections or replacements 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 these inspections or replacements:

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: