2024-16-09: Fuselage

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: 2024-16-09 The Boeing Company: Amendment 39-22815; Docket No. FAA-2024-0769; Project Identifier AD-2023-00556-T. (a) Effective Date This airworthiness directive (AD) is effective November 12, 2024. (b) Affected ADs This AD affects AD 2023-17-14, Amendment 39-22541 (88 FR 60111, August 31, 2023) (AD 2023-17-14). (c) Applicability This AD applies to The Boeing Company Model 777-200, -200LR, -300, -300ER, and 777F series airplanes, certificated in any category, as identified in Boeing Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023. (d) Subject Air Transport Association (ATA) of America Code 53, Fuselage. (e) Unsafe Condition This AD was prompted by a report indicating multiple findings of cracks in the fuselage skin common to the underwing longeron (UWL). The FAA is issuing this AD to address fuselage skin cracking caused by cold work surface upset that is not removed from the mating parts and high joint load transfer or significant local bending stresses at critical fastener locations. The unsafe condition, if not addressed, could result in an inability of a principal structural element (PSE) to sustain limit load, leading to reduced structural integrity of the airplane and possible loss of control of the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions Except as specified by paragraph (h) of this AD: At the applicable times specified in the "Compliance" paragraph of Boeing Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023, do all applicable actions identified in, and in accordance with, the Accomplishment Instructions of Boeing Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023. Note 1 to paragraph (g): Guidance for accomplishing the actions required by this AD can be found in Boeing Alert Service Bulletin 777-53A0100, dated March 16, 2023, which is referred to in Boeing Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023. Note 2 to paragraph (g): Guidance for accomplishing certain on-condition actions required by paragraph (g) of this AD can be found in Boeing Service Bulletin 777-53-0084, Revision 2, dated December 9, 2020; Boeing Service Bulletin 777-53-0087 Revision 1, dated March 4, 2020; and Boeing Alert Requirements Bulletin 777-57A0122 RB, dated October 8, 2021. (h) Exceptions to Requirements Bulletin Specifications (1) Where the Compliance Time columns of the tables in the "Compliance" paragraph of Boeing Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023, use the phrase "the original issue date of Requirements Bulletin 777-53A0100 RB," this AD requires using the effective date of this AD. (2) Where Boeing Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023, and any service information referenced in Boeing Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023, specifies contacting Boeing for repair instructions: This AD requires doing the repair using a method approved in accordance with the procedures specified in paragraph (j) of this AD. Note 3 to paragraph (h)(2): This note applies to paragraphs (h)(2) and (3) of this AD. Boeing Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023, refers to Boeing Service Bulletin 777-53-0084, Revision 2, dated December 9, 2020; Boeing Service Bulletin 777-53-0087, Revision 1, dated March 4, 2020; and Boeing Alert Requirements Bulletin 777-57A0122 RB, dated October 8, 2021. (3) Where any service information referenced in Boeing Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023, specifies applying a cap seal (sealant) to a fastener, fastener head, and fastener threads and collars inside the fuel tank, for this AD, during application of any cap seal to a fastener, fastener head, or fastener threads and collars inside the fuel tank, the cap seal must be applied using a cap sealing procedure with thickness greater than or equal to the dimensions given in Figure 1 to paragraph (h)(3) of this AD. Note 4 to paragraph (h)(3): Guidance on an acceptable cap sealing procedure for accomplishing the actions required by paragraph (h)(3) of this AD can be found in Boeing Model 777 Aircraft Maintenance Manual (AMM) section 28-11-00. Figure 1 to Paragraph (h)(3)-Cap Sealing Dimensions (all Dimensions are in Inches) ER08OC24.009 (4) Where Boeing Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023, specifies doing actions "in accordance with Revision 2 of Boeing Service Bulletin 777-53-0084," for this AD, where flagnote (f) of Figure 7 and Figure 22 of that referenced service information ("Revision 2 of Boeing Service Bulletin 777-53-0084") includes a sealant callout of Boeing Material Specification (BMS) 5-45 or an optional BMS 5-95, only BMS 5-45 is allowed. (5) Where Boeing Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023, specifies doing actions "in accordance with Revision 1 of Boeing Service Bulletin 777-53-0087," for this AD, where flagnote (f) of Figure 13 and Figure 49 of that referenced service information ("Revision 1 of Boeing Service Bulletin 777-53-0087") includes a sealant callout of BMS 5-45 or an optional BMS 5-95, only BMS 5-45 is allowed. (6) Where Boeing Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023, specifies doing actions "in accordance with the original issue of Boeing Alert Requirements Bulletin 777-57A0122 RB," for this AD, the exceptions specified in paragraph (h)(6)(i) through (v) of this AD apply to that referenced service information ("the original issue of Boeing Alert Requirements Bulletin 777-57A0122 RB") and the corrections identified in Boeing Multi Operator Message MOM-MOM-24-0054-01B, dated January 26, 2024, apply to that referenced service information. (i) Where the "Compliance" paragraph of the referenced service information identifies "Tables 1 through 50," the correct number of tables is Tables 1 through 54. (ii) The referenced service information does not specify the application of cap seals to underwing longeron fasteners, fastener heads, and fastener threads and collars for the airplane groups and configurations identified in paragraphs (h)(6)(ii)(A) through (D) of this AD. For those airplane groups and configurations, the application of a cap seal to the underwing longeron fasteners at the locations identified in Figures 81 and 144 is required during installation of the underwing longeron and must be applied using a cap sealing procedure with thickness greater than or equal to the dimensions given in Figure 1 to paragraph (h)(3) of this AD. (A) Groups 7 and 8, Configurations 5 through 8, on the left side. (B) Group 9, Configurations 1 and 2, on the left side. (C) Groups 7 and 8, Configurations 2, 6, 10, and 14, on the right side. (D) Group 9, Configurations 1 and 3, on the right side. (iii) For any inspection that may require the removal of fastener cap seals, if the cap seal is removed, a cap seal of BMS 5-45 sealant must be reapplied using a cap sealing procedure with a thickness equal to or greater than the dimensions specified in Figure 1 to paragraph (h)(3) of this AD before further flight after completion of the inspection. (iv) The referenced service information does not require the restoration of any sealant removed to accomplish high frequency eddy current and ultrasonic inspections external to the fuel tank in Figures 1, 7, 11, and 17. Following completion of any inspection required by those figures, replacement of the sealant described in paragraph (h)(6)(iv)(A) and repair of the sealant described in paragraph (h)(6)(iv)(B) of this AD, as applicable, is required. (A) Where any sealant was removed from the heads of fasteners, before further flight, cover and fillet seal the fasteners using BMS 5-45 or BMS 5-95 sealant. Note 5 to paragraph (h)(6)(iv)(A): Guidance for accomplishing the actions required by paragraph (h)(6)(iv)(A) of this AD can be found in the Boeing Standard Overhaul Practices Manual (SOPM) section 20-50-19. (B) Following any sealant replacement required by paragraph (h)(6)(iv)(A) of this AD, where any secondary fuel barrier coating was removed, before further flight, repair the secondary fuel barrier using BMS 5-81 sealant. Note 6 to paragraph (h)(6)(iv)(B): Guidance for accomplishing the actions required by paragraph (h)(6)(iv)(B) of this AD can be found in Boeing Model 777 Aircraft Maintenance Manual (AMM) section 28-11-00. (v) The Effectivity of the referenced service information does not include Boeing Model 777F series airplanes having line numbers 1713, 1717, 1720, and 1724 through 1742 inclusive. For those airplanes the applicable actions for Group 6 must be done. (i) Terminating Action for AD 2023-17-14 For airplanes on which a front spar lower chord modification specified in Boeing Alert Requirements Bulletin 777-57A0122 RB is done as part of the requirements of paragraphs (g) and (h)(6) of this AD, the modification requirements of paragraph (g) of AD 2023-17-14 are terminated for the applicable side (left or right) on which the modification was done. (j) 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 (k)(1) of this AD. Information may be emailed to: [email protected]. (2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the responsible Flight Standards Office. (3) 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. (k) Related Information (1) For more information about this AD, contact Luis Cortez-Muniz, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3958; email: [email protected]. (2) Material identified in this AD that is not incorporated by reference is available at the address specified in paragraph (l)(3) of this AD. (l) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference (IBR) 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 Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023. (ii) Boeing Multi Operator Message MOM-MOM-24-0054-01B, dated January 26, 2024. (3) For Boeing material, 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 [email protected]. Issued on August 1, 2024. Peter A. White, Deputy Director, Integrated Certificate Management Division, Aircraft Certification Service. [FR Doc. 2024-23117 Filed 10-7-24; 8:45 am]BILLING CODE 4910-13-P