AD 2026-05-15 ACTIVE

The FAA is adopting a new airworthiness directive (AD) for certain The Boeing Company Model 777-200LR and -300ER series airplanes. This AD was prompted by reports of chafing and arcing damage on the light emitting diode (LED) sidewall wire bundles. This AD requires a general visual inspection (GVI) of the sidewall light for chafing damage and applicable on-condition actions. The FAA is issuing this AD to address the unsafe condition on these products.

Final rule.

1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. 2. The FAA amends § 39.13 by adding the following new airworthiness directive: 2026-05-15 The Boeing Company: Amendment 39-23288; Docket No. FAA-2025-0348; Project Identifier AD-2024-00626-T. (a) Effective Date This airworthiness directive (AD) is effective April 20, 2026. (b) Affected ADs None. (c) Applicability This AD applies to The Boeing Company Model 777-200LR and -300ER series airplanes, certificated in any category, as identified in Boeing Special Attention Requirements Bulletin 777-33-0069 RB, dated October 15, 2024. (d) Subject Air Transport Association (ATA) of America Code 33, Lights. (e) Unsafe Condition This AD was prompted by reports of chafing and arcing damage on the light emitting diode (LED) sidewall wire bundles. The FAA is issuing this AD to prevent and address chafing damage on the LED sidewall wire bundles. The unsafe condition, if not addressed, could result in maintenance personnel contact with a live high-voltage electrical cable. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions Except as specified in paragraph (h) of this AD: At the applicable times specified in the "Compliance" paragraph of Boeing Special Attention Requirements Bulletin 777-33-0069 RB, dated October 15, 2024, do all applicable actions identified in, and in accordance with, the Accomplishment Instructions of Boeing Special Attention Requirements Bulletin 777-33-0069 RB, dated October 15, 2024. Note 1 to paragraph (g): Guidance for accomplishing the actions required by this AD can be found in Boeing Special Attention Service Bulletin 777-33-0069, dated October 15, 2024, which is referred to in Boeing Special Attention Requirements Bulletin 777-33-0069 RB, dated October 15, 2024. (h) Exceptions to Requirements Bulletin Specifications Where the "Boeing Recommended Compliance Time" column in the table under the "Compliance" paragraph of Boeing Special Attention Requirements Bulletin 777-33-0069 RB, dated October 15, 2024, refers to "the Original Issue date of Requirements Bulletin 777-33-0069 RB," this AD requires using the effective date of this AD. (i) Alternative Methods of Compliance (AMOCs) (1) The Manager, AIR-520, Continued Operational Safety 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 responsible Flight Standards Office, as appropriate. If sending information directly to the manager of the Continued Operational Safety Branch, send it to the attention of the person identified in paragraph (j)(1) of this AD. Information may be emailed to: AMOC@faa.gov. Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the responsible Flight Standards Office. (2) An AMOC that provides an acceptable level of safety may be used for any repair, modification, or alteration required by this AD if it is approved by The Boeing Company Organization Designation Authorization (ODA) that has been authorized by the Manager, AIR-520, Continued Operational Safety Branch, FAA, to make those findings. To be approved, the repair method, modification deviation, or alteration deviation must meet the certification basis of the airplane, and the approval must specifically refer to this AD. (j) Additional Information (1) For more information about this AD, contact Raja Vengadasalam, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3537; email: raja.vengadasalam@faa.gov. (2) Material identified in this AD that is not incorporated by reference is available at the address specified in paragraph (k)(3) this AD. (k) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference of the material listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this material as applicable to do the actions required by this AD, unless the AD specifies otherwise. (i) Boeing Special Attention Requirements Bulletin 777-33-0069 RB, dated October 15, 2024. (ii) [Reserved] (3) For the 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 . (4) 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. (5) You may view this material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email fr.inspection@nara.gov. Issued on March 9, 2026. Lona C. Saccomando, Acting Deputy Director, Integrated Certificate Management Division, Aircraft Certification Service. [FR Doc. 2026-05117 Filed 3-13-26; 8:45 am]BILLING CODE 4910-13-P

Background 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 777-200LR and -300ER series airplanes. The NPRM was published in the Federal Register on March 28, 2025 (90 FR 14055). The NPRM was prompted by reports of chafing and arcing damage on the LED sidewall wire bundles. In the NPRM, the FAA proposed to require a GVI of the sidewall light for chafing damage and applicable on-condition actions. The FAA is issuing this AD to address chafing damage on the LED sidewall wire bundles. The unsafe condition, if not addressed, could result in maintenance personnel contact with a live high-voltage electrical cable. Discussion of Final Airworthiness Directive Comments The FAA received comments from Boeing and ProTech Aero Services Limited (ProTech) who supported the NPRM without change. The FAA received an additional comment from American Airlines (American). The following presents the comment received on the NPRM and the FAA's response to the comment. Request for Clarification of Inspection Locations and Revised Illustrations American requested that the FAA clarify if the intent of figure 1 of Boeing Special Attention Requirements Bulletin 777-33-0069 RB, dated October 15, 2024 (the Boeing requirements bulletin), is to only inspect for wire chafing damage between the sidewall light and the power connector. American stated that figure 1 of the Boeing requirements bulletin does not show all the inspection locations or highlight that the inspection is limited to the area between the LED sidewall light harness and connector; it also does not show the different light sizes, harness routing, and stowage compartment sizes. American also requested that the FAA require Boeing to revise figures 2 and 3 of the Boeing requirements bulletin to include illustrations of all non-typical installations. Additionally, American stated that figure 2 of the Boeing requirements bulletin illustrates only a typical installation of a clip over the edge of the hole in the stowage compartment and does not account for non-typical wire routing configurations resulting from differences in stowage compartment and light sizes. The FAA clarifies that the inspection area for chafing damage to the sidewall light power connector wire bundle is illustrated in figure 1 of the Boeing requirements bulletin as the portion of the wire bundle that is marked with diagonal stripes and shaded light blue. The FAA disagrees with the request to revise figures 2 and 3 of the Boeing requirements bulletin. The FAA reviewed and approved the Boeing requirements bulletin prior to publication of the proposed AD and determined that it provides sufficient instructions and illustrations to correct the unsafe condition. If a specific configuration prevents an operator from accomplishing the actions specified in the Boeing requirements bulletin, the operator may request an alternative method of compliance (AMOC) in accordance with the procedures specified in paragraph (i) of this AD. No changes have been made to this AD in this regard. Conclusion 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. Material Incorporated by Reference Under 1 CFR Part 51 The FAA reviewed Boeing Special Attention Requirements Bulletin 777-33-0069 RB, dated October 15, 2024. This material specifies procedures for a GVI of the sidewall lights for wire chafing damage and applicable on-condition actions, including repairing the wire chafing damage, replacing the light, adjusting the wire routing, and installing a new wire clip, ringpost, and clamp. 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. Costs of Compliance The FAA estimates that this AD affects 31 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD: Estimated Costs Action Labor cost Parts cost Cost per product Cost on U.S. operators Inspection Up to 100 work-hours × $85 per hour = $8,500 $15,390 Up to $23,890 Up to $740,590. The FAA estimates the following costs to do any necessary actions 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 actions: On-Condition Costs Action Labor cost Parts cost Cost per product Repair or replacement, adjusting wire routing, and installing parts 1 work-hour × $85 per hour = $85 Up to $7,613 Up to $7,698. 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. 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. Regulatory Findings 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. List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. 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 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: 2026-05-15 The Boeing Company: Amendment 39-23288; Docket No. FAA-2025-0348; Project Identifier AD-2024-00626-T. (a) Effective Date This airworthiness directive (AD) is effective April 20, 2026. (b) Affected ADs None. (c) Applicability This AD applies to The Boeing Company Model 777-200LR and -300ER series airplanes, certificated in any category, as identified in Boeing Special Attention Requirements Bulletin 777-33-0069 RB, dated October 15, 2024. (d) Subject Air Transport Association (ATA) of America Code 33, Lights. (e) Unsafe Condition This AD was prompted by reports of chafing and arcing damage on the light emitting diode (LED) sidewall wire bundles. The FAA is issuing this AD to prevent and address chafing damage on the LED sidewall wire bundles. The unsafe condition, if not addressed, could result in maintenance personnel contact with a live high-voltage electrical cable. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions Except as specified in paragraph (h) of this AD: At the applicable times specified in the "Compliance" paragraph of Boeing Special Attention Requirements Bulletin 777-33-0069 RB, dated October 15, 2024, do all applicable actions identified in, and in accordance with, the Accomplishment Instructions of Boeing Special Attention Requirements Bulletin 777-33-0069 RB, dated October 15, 2024. Note 1 to paragraph (g): Guidance for accomplishing the actions required by this AD can be found in Boeing Special Attention Service Bulletin 777-33-0069, dated October 15, 2024, which is referred to in Boeing Special Attention Requirements Bulletin 777-33-0069 RB, dated October 15, 2024. (h) Exceptions to Requirements Bulletin Specifications Where the "Boeing Recommended Compliance Time" column in the table under the "Compliance" paragraph of Boeing Special Attention Requirements Bulletin 777-33-0069 RB, dated October 15, 2024, refers to "the Original Issue date of Requirements Bulletin 777-33-0069 RB," this AD requires using the effective date of this AD. (i) Alternative Methods of Compliance (AMOCs) (1) The Manager, AIR-520, Continued Operational Safety 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 responsible Flight Standards Office, as appropriate. If sending information directly to the manager of the Continued Operational Safety Branch, send it to the attention of the person identified in paragraph (j)(1) of this AD. Information may be emailed to: AMOC@faa.gov. Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the responsible Flight Standards Office. (2) An AMOC that provides an acceptable level of safety may be used for any repair, modification, or alteration required by this AD if it is approved by The Boeing Company Organization Designation Authorization (ODA) that has been authorized by the Manager, AIR-520, Continued Operational Safety Branch, FAA, to make those findings. To be approved, the repair method, modification deviation, or alteration deviation must meet the certification basis of the airplane, and the approval must specifically refer to this AD. (j) Additional Information (1) For more information about this AD, contact Raja Vengadasalam, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3537; email: raja.vengadasalam@faa.gov. (2) Material identified in this AD that is not incorporated by reference is available at the address specified in paragraph (k)(3) this AD. (k) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference of the material listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this material as applicable to do the actions required by this AD, unless the AD specifies otherwise. (i) Boeing Special Attention Requirements Bulletin 777-33-0069 RB, dated October 15, 2024. (ii) [Reserved] (3) For the 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 . (4) 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. (5) You may view this material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email fr.inspection@nara.gov. Issued on March 9, 2026. Lona C. Saccomando, Acting Deputy Director, Integrated Certificate Management Division, Aircraft Certification Service.

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2025-0348; 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-2025-0348.

Raja Vengadasalam, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3537; email: raja.vengadasalam@faa.gov.