Document headings vary by document type but may contain
                    the following: the agency or agencies that issued and signed a document
the number of the CFR title and the number of each part
                      the document amends, proposes to amend, or is directly
                      related to
the agency docket number / agency internal file number
the RIN which identifies each regulatory action listed in
                      the Unified Agenda of Federal Regulatory and Deregulatory
                      Actions See the
                    Document Drafting Handbook
                    for more details.
 Department of Transportation Federal Aviation Administration 14 CFR Part 39
[Docket No. FAA-2024-2144; Project Identifier AD-2024-00424-T]
RIN 2120-AA64
 AGENCY: Federal Aviation Administration (FAA), DOT.
 ACTION: Notice of proposed rulemaking (NPRM).
 SUMMARY: The FAA proposes to supersede Airworthiness Directive (AD) 2022-15-06, which applies to all The Boeing Company Model 777-200, -200LR, -300, -300ER, and 777F series airplanes. AD 2022-15-06 requires disconnecting certain connectors and capping and stowing the wires that had been attached to the affected transorb modules. Since the FAA issued AD 2022-15-06, the agency has determined additional connectors are affected. Also, a replacement has been developed to address the unsafe condition, which would terminate the existing actions. This proposed AD would continue to require the actions specified in AD 2022-15-06 and would require those actions for additional connectors. This proposed AD would also require determining if affected transorb modules are installed, replacing or testing affected transorb modules, and applicable on-condition actions. This proposed AD would also prohibit the installation of affected parts. The FAA is proposing this AD to address the unsafe condition on these products.
 DATES: The FAA must receive comments on this proposed AD by November 12, 2024.
 ADDRESSES: 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 
                        *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 
                        ( print page 78828)
                        W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
                    *Hand Delivery:*
                         Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. *AD Docket:*
                         You may examine the AD docket at 
                        *regulations.gov*
                         under Docket No. FAA-2024-2144; 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 NPRM, any comments received, and other information. The street address for Docket Operations is listed above. *Material Incorporated by Reference:* For the material identified in this proposed 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-2024-2144.
 FOR FURTHER INFORMATION CONTACT: Raja Vengadasalam, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3859; email: 
                        *raja.vengadasalam@faa.gov.*


SUPPLEMENTARY INFORMATION: Comments Invited The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the 
                    **ADDRESSES**
                     section. Include “Docket No. FAA-2024-2144; Project Identifier AD-2024-00424-T” at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this proposal because of those comments. Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to 
                    *regulations.gov,*
                     including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM. Confidential Business Information CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as “PROPIN.” The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this NPRM. Submissions containing CBI should be sent to Raja Vengadasalam, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3859; email: 
                    *raja.vengadasalam@faa.gov.*
                     Any commentary that the FAA receives that is not specifically designated as CBI will be placed in the public docket for this rulemaking. Background The FAA issued AD 2022-15-06, Amendment 39-22126 (87 FR 47334, August 3, 2022) (AD 2022-15-06), for all The Boeing Company Model 777-200, -200LR, -300, -300ER, and 777F series airplanes. AD 2022-15-06 was prompted by high electrical resistance within the gust suppression sensor (GSS) transorb modules due to corrosion on the transorb threads. AD 2022-15-06 requires disconnecting certain connectors and capping and stowing the wires that had been attached to the affected transorb modules. The FAA issued AD 2022-15-06 to address high electrical resistance in both transorb modules, which can result in two actuator control electronics (ACEs) being exposed to damaging lightning transient voltages in excess of the qualification levels, potentially inducing erroneous or oscillatory outputs to flight control surfaces. The unsafe condition, if not addressed, could result in loss of control of the airplane. Actions Since AD 2022-15-06 Was Issued Since the FAA issued AD 2022-15-06, a replacement mitigating action has been developed to address the unsafe condition, which would terminate the existing actions. The preamble to AD 2022-15-06 explains that the FAA considers the requirements “interim action” and may consider further rulemaking. The FAA has now determined that further rulemaking is indeed necessary, and the replacement specified in this proposed AD follows from that determination. In addition, Boeing and several operators notified the FAA that certain bundles/connectors were not identified in AD 2022-15-06. Boeing noted that there are connector designation variances between earlier and later Model 777 airplanes and that bundle/connector W7314/D02099P is on the right-hand side of certain line number airplanes. Boeing stated it sent a Boeing multi-operator message to operators to reduce confusion and recommended bundle/connector W7314/D02099P be identified as an affected bundle/connector. American Airlines, Qatar Airways, and United Airlines also noted that bundle/connector W7314/D02099P is not identified in AD 2022-15-06. United Airlines, All Nippon Airways, and Kilitta Air, LLC, noted that bundle/connector W6313/D02098P is not identified in AD 2022-15-06 but it is identified as a bundle/connector for certain airplanes. The FAA has determined the additional connectors are affected by the unsafe condition. Therefore, this proposed AD would require that operators disconnect the connectors and cap and stow the wires to bundles/connectors W6313/D02098P and W7314/D02099P until the proposed replacement is done as specified in paragraph (h) of this proposed AD. FAA's Determination The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design. Material Incorporated by Reference Under 1 CFR Part 51 The FAA reviewed Boeing Alert Requirements Bulletin 777-27A0125 RB, dated February 3, 2023. This material specifies procedures for replacing affected transorb modules with new or serviceable transorb modules or testing affected transorb modules and accomplishing applicable on-condition actions. The on-condition actions include part marking any module that meets certain specifications or replacing any modules that do not meet the specifications. 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.
                    ( print page 78829) Proposed AD Requirements in This NPRM This proposed AD would retain all requirements of AD 2022-15-06 and would require those actions for additional connectors. This proposed AD would also require determining if affected transorb modules are installed, replacing or testing affected transorb modules, and applicable on-condition actions. This proposed AD would also prohibit the installation of affected parts. For information on the procedures and compliance times, see Boeing Alert Requirements Bulletin 777-27A0125 RB, dated February 3, 2023, at 
                    *regulations.gov*
                     under Docket No. FAA-2024-2144. Differences Between This Proposed AD and the Referenced Material The effectivity of Boeing Alert Requirements Bulletin 777-27A0125 RB, dated February 3, 2023, is limited to Model 777-200, -200LR, -300, -300ER, and 777F series airplanes, having certain line numbers. However, the applicability of this proposed AD includes all Model 777-200, -200LR, -300, -300ER, and 777F series airplanes. Because the affected parts are rotable parts, the FAA has determined that these parts could later be installed on airplanes that were initially delivered with acceptable parts, thereby subjecting those airplanes to the unsafe condition. The FAA has confirmed with Boeing that the Accomplishment Instructions in Boeing Alert Requirements Bulletin 777-27A0125 RB, dated February 3, 2023, are applicable to the expanded group of airplanes. Costs of Compliance The FAA estimates that this AD, if adopted as proposed, would affect 312 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD: Estimated Costs
Action
Labor cost
Parts cost
Cost per
                             product
Cost on U.S.
                             operatorsDisconnecting connectors, capping and stowing wires (retained actions from AD 2022-15-06)
3 work-hours × $85 per hour = $255
$0
$255
$79,560.Disconnecting additional connectors, capping and stowing wires (new proposed action)
3 work-hours × $85 per hour = $255
$0
$255
$79,560.Determining if affected transorb modules are installed, and replacing or testing affected modules (new proposed action)
Up to 3 work-hours × $85 per hour = $255
Up to $3,668
Up to $3,923
Up to $1,223,976.
 The FAA estimates the following costs to do any necessary on-condition actions that would be required based on the results of the proposed testing. 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
                             productPart marking or replacing affected modules
Up to 3 work-hours × $85 per hour = $255
Up to $3,668
Up to $3,923.
 The FAA has included all known costs in its cost estimate. According to the manufacturer, however, some or all of the costs of this proposed AD may be covered under warranty, thereby reducing the cost impact on affected operators. 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 The FAA determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 this proposed regulation: (1) Is not a “significant regulatory action” under Executive Order 12866, (2) Would not affect intrastate aviation in Alaska, and (3) Would 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 Proposed Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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
 2.The FAA amends § 39.13 by: a.Removing Airworthiness Directive (AD) 2022-15-06, Amendment 39-22126 ( 87 FR 47334, August 3, 2022), and b.Adding the following new AD: **The Boeing Company:**
                         Docket No. FAA-2024-2144; Project Identifier AD-2024-00424-T. (a) Comments Due Date The FAA must receive comments on this airworthiness directive (AD) by November 12, 2024. (b) Affected ADs This AD replaces AD 2022-15-06, Amendment 39-22126 (87 FR 47334, August 3, 2022) (AD 2022-15-06). (c) Applicability This AD applies to all The Boeing Company Model 777-200, -200LR, -300, -300ER, and 777F series airplanes, certificated in any category. (d) Subject Air Transport Association (ATA) of America Code 27, Flight controls. (e) Unsafe Condition This AD was prompted by high electrical resistance within the gust suppression sensor (GSS) transorb modules due to corrosion on the transorb threads and insufficient engagement of the anti-rotation teeth. The FAA is issuing this AD to address high electrical resistance in both transorb modules, which can result in two actuator control electronics (ACEs) being exposed to damaging lightning transient voltages in excess of the qualification levels, potentially inducing erroneous or oscillatory outputs to flight control surfaces. The unsafe condition, if not addressed, could result in loss of control of the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Retained Requirement To Disconnect, Cap, and Stow Transorb Module Connectors, With No Changes This paragraph restates the requirements of paragraph (g) of AD 2022-15-06, with no changes. At the later of the times specified in paragraphs (g)(1) and (2) of this AD: Disconnect the connectors and cap and stow the wires to bundles/connectors W7314/D02006P and W7579/D02005P from the transorb module part numbers CLPT-12SP-06, -07, and -67. **Note 1 to the introductory text of paragraph (g):**
                         Guidance on locating wire bundles/connectors W7314/D02006P and W7579/D02005P can be found in Section 05-55-43 of the Boeing 777 aircraft maintenance manual. **Note 2 to the introductory text of paragraph (g):**
                         Guidance on capping and stowing the wires once they are disconnected can be found in Section 20-10-11 of the Boeing Standard Wiring Practices Manual. (1) Before the accumulation of 75,000 total flight hours or 23,000 total flight cycles, whichever occurs first. (2) Within 3 months after August 18, 2022 (the effective date of AD 2022-15-06). (h) New Requirement To Disconnect, Cap, and Stow Certain Other Transorb Module Connectors At the later of the times specified in paragraphs (h)(1) and (2) of this AD: Disconnect the connectors and cap and stow the wires to bundles/connectors W6313/D02098P and W7314/D02099P from the transorb module part numbers CLPT-12SP-06, -07, and -67. **Note 3 to the introductory text of paragraph (h):**
                         Guidance on locating wire bundles/connectors W6313/D02098P and W7314/D02099P can be found in Section 05-55-43 of the Boeing 777 aircraft maintenance manual. **Note 4 to the introductory text of paragraph (h):**
                         Guidance on capping and stowing the wires once they are disconnected can be found in Section 20-10-11 of the Boeing Standard Wiring Practices Manual. (1) Before the accumulation of 75,000 total flight hours or 23,000 total flight cycles, whichever occurs first. (2) Within 3 months after the effective date of this AD. (i) New Required Actions (1) For airplanes with original airworthiness certificate or original export certificate of airworthiness issued on or before the effective date of this AD: At the later of the times specified in paragraph (i)(1)(i) or (ii) of this AD, do an inspection to determine if any airplane has a transorb module with part number CLPT-12SP-06, -07, or -67 installed. A review of airplane maintenance records is acceptable in lieu of the inspection if the part numbers can be conclusively determined from that review. (i) Within 24 months after the effective date of this AD. (ii) Within 24 months after the date of issuance of the original standard certificate of airworthiness or the original export certificate of airworthiness. (2) If, during any inspection or records review required by paragraph (i)(1) of this AD, any transorb module with part number CLPT-12SP-06, -07, or -67 is found: Except as specified by paragraph (j) of this AD, at the applicable times specified in the “Compliance” paragraph of Boeing Alert Requirements Bulletin 777-27A0125 RB, dated February 3, 2023, do all applicable actions identified in, and in accordance with, the Accomplishment Instructions of Boeing Alert Requirements Bulletin 777-27A0125 RB, dated February 3, 2023. Doing the replacement required by this paragraph terminates the requirements of paragraphs (g) and (h) of this AD. **Note 5 to paragraph (i)(2):**
                         Guidance for accomplishing the actions required by paragraph (i)(2) of this AD can be found in Boeing Alert Service Bulletin 777-27A0125, dated February 3, 2023, which is referred to in Boeing Alert Requirements Bulletin 777-27A0125 RB, dated February 3, 2023. (j) Exception to Requirements Bulletin Specifications Where the Compliance Time column of the table in the “Compliance” paragraph of Boeing Alert Requirements Bulletin 777-27A0125 RB, dated February 3, 2023, refers to the original issue date of Requirements Bulletin 777-27A0125 RB, this AD requires using the effective date of this AD. (k) Parts Installation Prohibition As of the effective date of this AD, no person may install a transorb module, part numbers CLPT-12SP-06, CLPT-12SP-07, and CLPT-12SP-67, on any airplane. (l) 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 certification office, send it to the attention of the person identified in paragraph (m)(1) of this AD. Information may be emailed to: 
                        *AMOC@faa.gov.* (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. (4) AMOCs approved for AD 2022-15-06 are approved as AMOCs for the corresponding provisions of paragraph (g) of this AD. (m) Related Information (1) For more information about this AD, contact Raja Vengadasalam, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3859; 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 (n)(3) of this AD. (n) 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.
                        ( print page 78831) (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 777-27A0125 RB, dated February 3, 2023. (ii) [Reserved] (3) For the 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 September 18, 2024. Peter A. White, Deputy Director, Integrated Certificate Management Division, Aircraft Certification Service.


[FR Doc. 2024-21689 Filed 9-25-24; 8:45 am] BILLING CODE 4910-13-P