2024-09353. Airworthiness Directives; Airbus SAS Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for certain Airbus SAS Model A350-941 airplanes. This AD was prompted by a report of cracks found on the trunnion arms of the inboard flap assemblies. This AD requires repetitive inspections for cracking of the trunnion arms of the inboard flap assembly, and applicable corrective actions, as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. This AD also prohibits the installation of affected parts. The FAA is issuing this AD to address the unsafe condition on these products.

DATES:

This AD is effective June 6, 2024.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of June 6, 2024.

ADDRESSES:

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2023-1883; 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, the mandatory continuing airworthiness information (MCAI), 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 EASA material incorporated by reference in this AD, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone [phone]; email [e-mail]; website easa.europa.eu. You may find this material on the EASA website at ad.easa.europa.eu.

• 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 in the AD docket at regulations.gov under Docket No. FAA-2023-1883.

FOR FURTHER INFORMATION CONTACT:

Dat Le, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone [phone]; email [e-mail].

SUPPLEMENTARY INFORMATION:

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 Airbus SAS Model A350-941 airplanes. The NPRM published in the Federal Register on September 22, 2023 (88 FR 65328). The NPRM was prompted by AD 2023-0132, dated July 3, 2023 (EASA AD 2023-0132) (also referred to as the MCAI), issued by EASA, which is the Technical Agent for the Member States of the European Union. The MCAI states that cracks were found on the trunnion arms of the inboard flap assemblies that were made of forging aluminum 7037.

In the NPRM, the FAA proposed to require repetitive inspections for cracking of the trunnion arms of the inboard flap assembly, and applicable corrective actions, as specified in EASA AD 2023-0132. The NPRM also proposed to prohibit the installation of affected parts. The FAA is issuing this AD to address potential cracks of the trunnion arms. The unsafe condition, if not detected and corrected, could adversely affect the structural integrity of the trunnion arms.

You may examine the MCAI in the AD docket at regulations.gov under Docket No. FAA-2023-1883.

Discussion of Final Airworthiness Directive

Comments

The FAA received a comment from Delta Airlines. The following presents the comment received on the NPRM and the FAA's response.

Request To Clarify Requirements

Delta Air Lines (Delta) requested that the proposed AD be revised to add a clear statement addressing the relation between the instructions in the service information specified in EASA AD 2023-0132 and paragraph (i)(2) of the proposed AD for any deviations to the instructions, including those that are Required for Compliance (RC). Delta pointed out that a note in Paragraph 3., Accomplishment Instructions, of Airbus Service Bulletin A350-57-P077, dated January 31, 2023, states to contact Airbus for any deviations to the instructions, including those that are RC. Delta added that paragraph (i)(2) of the proposed AD states that for any requirement in the AD to obtain instructions from a manufacturer, the instructions must be done using a method approved by the FAA, EASA, or Airbus' EASA Design Organization Approval (DOA). Delta provided several examples of cases where it has obtained approval from the manufacturer in accordance with the requirement defined in the proposed AD—a method that is DOA approved—and wondered if those types of deviations from instructions found in RC steps that are obtained from the manufacturer may be implemented without further FAA approval. Based on the language in the service information and paragraph (i)(2) of the proposed AD, Delta explained that it interprets this to mean that approval for any deviations from the service information—including RC steps—with a DOA approval may be used without further FAA approval.

The FAA disagrees with revising the regulatory text of this AD. However, the following explanation is provided for clarification of the RC process. Any deviation to any and all RC actions identified in required service information as “in accordance with” a specific method requires approval of an FAA alternative method of compliance (AMOC). The “contact the manufacturer” language in paragraph (i)(2) of this AD applies to RC actions within the service information that specify, for example, to “contact the manufacturer [ e.g., Airbus] for repair instructions and do the repair.”

If the accomplishment step in the service information is labeled RC and has substeps or tasks with no paragraph designation under the labeled RC step, then all of the substeps or tasks must also be completed. In addition, if an accomplishment step in the service information is marked RC and states to do the work “in accordance with” a figure, drawing, or illustration, then all of the information in the figure, drawing, or illustration is mandatory. If a step is marked RC and a procedure or document must be followed to accomplish a task in a service bulletin, the appropriate terminology to cite the procedure or document is “in accordance with.” However, if a step is marked RC and a procedure or document may be followed to accomplish an action ( e.g., the design approval holder's procedure or document may be used, but an FAA-accepted procedure could also be used), the appropriate terminology to use to cite the procedure or document is “refer to . . . as an accepted procedure.”

Additional Changes Made to This AD

Since the FAA issued the NPRM, EASA revised EASA AD 2023-0132 and issued EASA AD 2023-0132R1, dated March 20, 2024, which adds an optional terminating action for the repetitive inspections.

The FAA has revised paragraph (g) of this AD to also refer to EASA AD 2023-0132R1, dated March 20, 2024, as an appropriate source of service information for accomplishing the required actions.

The FAA has revised paragraph (c) of this AD to refer to EASA AD 2023-0132R1, dated March 20, 2024, for the affected airplanes, which are the same between EASA AD revisions.

Conclusion

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 reviewed the relevant data, considered the comment 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 this product. Except for minor editorial changes, and any other changes described previously, this AD is adopted as proposed in the NPRM. None of the changes will increase the economic burden on any operator.

Related Service Information Under 1 CFR Part 51

EASA AD 2023-0132 specifies procedures for repetitive ultrasonic inspections for cracking of the trunnion arms of the inboard flap assemblies, and corrective actions, as applicable. Corrective actions include obtaining and following repair instructions if any cracking is found. EASA AD 2023-0132 also prohibits the installation of affected parts.

EASA AD 2023-0132R1, dated March 20, 2024, specifies the same procedures as EASA AD 2023-0132 and provides on optional terminating action for the repetitive inspections, which consists of replacing the left-hand and right-hand inboard flap, as applicable, with a modified inboard flap.

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 4 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD:

Estimated Costs for Required Actions

Labor cost	Parts cost	Cost per product	Cost on U.S. operators
Up to 17 work-hours × $85 per hour = $1,445	$10	Up to $1,455	Up to $5,820.

The FAA has received no definitive data on which to base the cost estimates for the on-condition repairs specified in this AD.

Estimated Costs for Optional Actions

Labor cost	Parts cost	Cost per product
Up to 122 work-hours × $85 per hour = $10,370	Up to $31,930	Up to $42,300.

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:

2024-08-01 Airbus SAS: Amendment 39-22734; Docket No. FAA-2023-1883; Project Identifier MCAI-2023-00804-T.

(a) Effective Date

This airworthiness directive (AD) is effective June 6, 2024.

(b) Affected ADs

None.

(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 2023-0132R1, dated March 20, 2024 (EASA AD 2023-0132R1).

(d) Subject

Air Transport Association (ATA) of America Code: 57, Wings.

(e) Unsafe Condition

This AD was prompted by a report of cracks found on the trunnion arms of the inboard flap assemblies. The FAA is issuing this AD to address potential cracks of the trunnion arms. The unsafe condition, if not addressed, could adversely affect the structural integrity of the trunnion arms.

(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 2023-0132, dated July 3, 2023 (EASA AD 2023-0132) or EASA AD 2023-0132R1.

(h) Exceptions to EASA AD 2023-0132 and EASA AD 2023-0132R1

(1) Where EASA AD 2023-0132 refers to its effective date, or EASA AD 2023-0132R1 refers to July 17, 2023 (the effective date of EASA AD 2023-0132), this AD requires using the effective date of this AD.

(2) Where paragraph (2) of EASA AD 2023-0132 and EASA AD 2023-0132R1 specifies if “any crack is detected, before next flight, contact Airbus for approved instructions and, within the compliance time(s) specified in those instructions, accomplish those instructions accordingly,” this AD requires replacing that text with “if any cracking is detected, the cracking must be repaired before further flight 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) This AD does not adopt the “Remarks” section of EASA AD 2023-0132 and EASA AD 2023-0132R1.

(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: [e-mail]. 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 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: [phone]; email: [e-mail].

(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 2023-0132, dated July 3, 2023.

(ii) EASA AD 2023-0132R1, dated March 20, 2024.

Note 1 to paragraph (k)(2)(ii): EASA AD 2023-0132R1 can be accessed in the zipped file at the bottom of the web page for EASA AD 2023-0132. When EASA posts a revised AD on their website, they watermark the previous AD as “Revised,” alter the file name by adding “_revised” to the end, and move it into a zipped file attached at the bottom of the AD web page.

(3) For EASA AD 2023-0132 and EASA AD 2023-0132R1, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone [phone]; email [e-mail]; website easa.europa.eu. You may find this EASA AD on the EASA website ad.easa.europa.eu.

(4) You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th Street, 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 [e-mail].

Issued on April 12, 2024.

Victor Wicklund,

Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.