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 Department of Transportation Federal Aviation Administration 14 CFR Part 39
[Docket No. FAA-2023-1887; Project Identifier MCAI-2023-00543-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) 2020-24-12, which applies to certain Airbus SAS Model A350-941 airplanes. AD 2020-24-12 requires replacing certain center wing box (CWB) fasteners with fasteners having improved friction efficiency. Since the FAA issued AD 2020-24-12, additional work was introduced to ensure the correct application of the fuel vapor barrier structure paint on the outside of the CWB. This proposed AD would continue to require the actions in AD 2020-24-12 and would require the additional work, as specified in a European Union Aviation Safety Agency (EASA) AD, which is proposed for incorporation by reference (IBR). 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 13, 2023.
 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 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-2023-1887; 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, the mandatory continuing airworthiness information (MCAI), any comments received, and other information. The street address for Docket Operations is listed above. *Material Incorporated by Reference:* For the EASA AD identified in this NPRM, you may contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999 000; email*ADs@easa.europa.eu;*
                         website 
                        *easa.europa.eu.*
                         You may find this material on the EASA website at 
                        *ad.easa.europa.eu.*
                         It is also available at 
                        *regulations.gov*
                         under Docket No. FAA-2023-1887.
                    You may view this service information 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.
 FOR FURTHER INFORMATION CONTACT: Dat Le, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone (516) 228-7317; email 
                        *dat.v.le@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 
                    **ADDRESSES**
                    . Include “Docket No. FAA-2023-1887; Project Identifier MCAI-2023-00543-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 
                    ( print page 65832)
                    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 Dat Le, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone (516) 228-7317; email 
                    *dat.v.le@faa.gov.*
                     Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking. Background The FAA issued AD 2020-24-12, Amendment 39-21342 (85 FR 76949, December 1, 2020) (AD 2020-24-12), for certain Airbus SAS Model A350-941 airplanes. AD 2020-24-12 was prompted by an MCAI originated by EASA, which is the Technical Agent for the Member States of the European Union. EASA issued AD 2020-0123, dated May 29, 2020 (EASA AD 2020-0123), to correct an unsafe condition. AD 2020-24-12 requires replacing certain CWB fasteners with fasteners having improved friction efficiency. The FAA issued AD 2020-24-12 to address CWB fastener rotation. This condition, if not corrected, could lead to cracking of the fastener head sealant cover, followed by fuel vapor leakage inside the cabin, possibly resulting in injury to airplane occupants. Actions Since AD 2020-24-12 Was Issued Since the FAA issued AD 2020-24-12, EASA superseded AD 2020-0123 and issued EASA AD 2023-0068, dated March 30, 2023 (EASA AD 2023-0068) (also referred to as the MCAI), to correct an unsafe condition for certain Airbus SAS Model A350-941 airplanes. The MCAI states that during flight and fatigue testing it was discovered that some fasteners can rotate inside their CWB fastener holes. Further investigation identified insufficient friction for the application. After EASA issued AD 2020-0123, it was determined that additional work is necessary to ensure the correct application of the fuel vapor barrier structure paint on the outside of the CWB. CWB fastener rotation, if not corrected, can lead to a crack of the fastener head sealant cover, followed by fuel vapor leakage inside the cabin, possibly resulting in injury to airplane occupants. The FAA is proposing this AD to address the unsafe condition on these products. You may examine the MCAI in the AD docket at 
                    *regulations.gov*
                     under Docket No. FAA-2023-1887. Explanation of Retained Requirements Although this proposed AD does not explicitly restate the requirements of AD 2020-24-12, this proposed AD would retain all of the requirements of AD 2020-24-12. Those requirements are referenced in EASA AD 2023-0068, which, in turn, is referenced in paragraph (g) of this proposed AD. Related Service Information Under 1 CFR Part 51 EASA AD 2023-0068 specifies procedures for replacing the affected CWB fasteners with fasteners having improved friction efficiency, and for doing additional work on previously modified airplanes to ensure the correct application of the fuel vapor barrier structure paint from outside the CWB. 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. FAA's Determination This product has been approved by the aviation authority of another country and is approved for operation in the United States. Pursuant to the FAA's bilateral agreement with this State of Design Authority, it has notified the FAA of the unsafe condition described in the MCAI referenced above. The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop in other products of the same type design. Proposed AD Requirements in This NPRM This proposed AD would retain all requirements of AD 2020-24-12. This proposed AD would also require accomplishing the applicable actions specified in EASA AD 2023-0068 described previously, except for any differences identified as exceptions in the regulatory text of this proposed AD. Explanation of Required Compliance Information In the FAA's ongoing efforts to improve the efficiency of the AD process, the FAA developed a process to use some civil aviation authority (CAA) ADs as the primary source of information for compliance with requirements for corresponding FAA ADs. The FAA has been coordinating this process with manufacturers and CAAs. As a result, the FAA proposes to incorporate EASA AD 2023-0068 by reference in the FAA final rule. This proposed AD would, therefore, require compliance with EASA AD 2023-0068 in its entirety through that incorporation, except for any differences identified as exceptions in the regulatory text of this proposed AD. Using common terms that are the same as the heading of a particular section in EASA AD 2023-0068 does not mean that operators need comply only with that section. For example, where the AD requirement refers to “all required actions and compliance times,” compliance with this AD requirement is not limited to the section titled “Required Action(s) and Compliance Time(s)” in EASA AD 2023-0068. Service information required by EASA AD 2023-0068 for compliance will be available at 
                    *regulations.gov*
                     under Docket No. FAA-2023-1887 after the FAA final rule is published. Costs of Compliance The FAA estimates that this AD, if adopted as proposed, would affect 13 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD: Estimated Costs for Required Actions
Action
Labor cost
Parts cost
Cost per
                             product
Cost on U.S.
                             operatorsRetained actions from AD 2020-24-12
307 work-hours × $85 per hour = $26,095
$5,900
$31,995
$415,935New proposed actions
174 work-hours × $85 per hour = $14,790
900
15,690
203,970
 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.
                    ( print page 65833) 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) 2020-24-12, Amendment 39-21342 ( 85 FR 76949, December 1, 2020); and b.Adding the following new AD: **Airbus SAS:**
                         Docket No. FAA-2023-1887; Project Identifier MCAI-2023-00543-T. (a) Comments Due Date The FAA must receive comments on this airworthiness directive (AD) by November 13, 2023. (b) Affected ADs This AD replaces AD 2020-24-12, Amendment 39-21342 (85 FR 76949, December 1, 2020) (AD 2020-24-12). (c) Applicability This AD applies to Airbus SAS Model A350-941 airplanes, certificated in any category, as identified in European Union Aviation Safety Agency (EASA) AD 2023-0068, dated March 30, 2023 (EASA AD 2023-0068). (d) Subject Air Transport Association (ATA) of America Code 57, Wings. (e) Unsafe Condition This AD was prompted by reports that certain central wing box (CWB) fasteners had rotated inside the fastener holes due to insufficient friction for the application, and by the determination that additional work is necessary to ensure the correct application of the fuel vapor barrier structure paint on the outside of the CWB. The FAA is issuing this AD to address CWB fastener rotation. The unsafe condition, if not corrected, could lead to cracking of the fastener head sealant cover, followed by fuel vapor leakage inside the cabin, possibly resulting in injury to airplane occupants. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Requirements Except as specified in paragraph (h) of this AD: Comply with all required actions and compliance times specified in, and in accordance with, EASA AD 2023-0068. (h) Exceptions to EASA AD 2023-0068 This AD does not adopt the “Remarks” section of EASA AD 2023-0068. (i) Additional AD Provisions The following provisions also apply to this AD: (1) 
                        *Alternative Methods of Compliance (AMOCs):*
                         The Manager, International Validation 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 International Validation Branch, send it to the attention of the person identified in paragraph (j) of this AD. Information may be emailed to: 
                        *9-AVS-AIR-730-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) 
                        *Contacting the Manufacturer:*
                         For any requirement in this AD to obtain instructions from a manufacturer, the instructions must be accomplished using a method approved by the Manager, International Validation Branch, FAA; or EASA; or Airbus SAS's EASA Design Organization Approval (DOA). If approved by the DOA, the approval must include the DOA-authorized signature. (3) 
                        *Required for Compliance (RC):*
                         Except as required by paragraph (i)(2) of this AD, if any service information contains procedures or tests that are identified as RC, those procedures and tests must be done to comply with this AD; any procedures or tests that are not identified as RC are recommended. Those procedures and tests that are not identified as RC may be deviated from using accepted methods in accordance with the operator's maintenance or inspection program without obtaining approval of an AMOC, provided the procedures and tests identified as RC can be done and the airplane can be put back in an airworthy condition. Any substitutions or changes to procedures or tests identified as RC require approval of an AMOC. (j) Additional Information For more information about this AD, contact Dat Le, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone (516) 228-7317; email 
                        *dat.v.le@faa.gov.* (k) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this service information as applicable to do the actions required by this AD, unless this AD specifies otherwise. (i) European Union Aviation Safety Agency (EASA) AD 2023-0068, dated March 30, 2023. (ii) [Reserved] (3) For EASA AD 2023-0068, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999 000; email 
                        *ADs@easa.europa.eu;*
                         website 
                        *easa.europa.eu.*
                         You may find this EASA AD on the EASA website at 
                        *ad.easa.europa.eu.* (4) You may view this service information 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 service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, email 
                        *fr.inspection@nara.gov,*
                         or go to: 
                        *www.archives.gov/​federal-register/​cfr/​ibr-locations.html.* Issued on September 18, 2023. Victor Wicklund, Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.


[FR Doc. 2023-20508 Filed 9-25-23; 8:45 am] BILLING CODE 4910-13-P