2023-11591. Airworthiness Directives; Airbus SAS Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for certain Airbus SAS Model A350–941 and A350–1041 airplanes. This proposed AD was prompted by reports that excessively deep spot faces on the front engine mounting bolt holes on the wing pylon were detected on the production line. This proposed AD would require a one-time inspection for clash (interference) of the three front engine mounting bolt holes on both the left and right wing pylons, and, depending on findings, accomplishment of applicable corrective actions, 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 July 17, 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: [phone].

• 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–2023–1056; 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 material that is proposed for IBR in this NPRM, 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. It is also available at regulations.gov under Docket No. FAA–2023–1056.

• You may view this service information 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.

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:

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–2023–1056; Project Identifier MCAI–2023–00179–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 Dat Le, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone [phone]; email [e-mail]. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking.

Background

EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2023–0026, dated January 30, 2023 (EASA AD 2023–0026) (also referred to as the MCAI), to correct an unsafe condition for certain Airbus SAS Model A350–941 and A350–1041 airplanes. The MCAI states that excessively deep spot faces have been detected on the production line on rib 1 at the level of the front engine mount bolting. This could cause possible integration issues between the pylon and the front engine mount, which could lead to interference damage. This condition, if not detected and corrected, could lead to a reduced fatigue life, which could adversely affect the structural integrity of the airplane.

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–2023–1056.

Related Service Information Under 1 CFR Part 51

EASA AD 2023–0026 specifies procedures for a one-time inspection for clash of the three pylon bolt holes at rib 1 (forward engine attachment on pylon), on both the left and right wing pylons, and applicable corrective actions. Corrective actions include installing the post-mod retention bracket assembly; accomplishing a detailed inspection and a high frequency eddy current (HFEC) inspection or a penetrant inspection on rib 1 for damage (cracks, scratches, or erosion of the protective coating); measuring the spot face depth and pylon thickness and obtaining and following instructions if incorrect spot face depth or pylon thickness at the spot face are found; and repair. 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 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 the State of Design Authority, it has notified the FAA of the unsafe condition described in the MCAI described 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 designs.

Proposed AD Requirements in This NPRM

This proposed AD would require accomplishing the actions specified in EASA AD 2023–0026 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 2023–0026 by reference in the FAA final rule. This proposed AD would, therefore, require compliance with EASA AD 2023–0026 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 2023–0026 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 2023–0026. Service information required by EASA AD 2023–0026 for compliance will be available at regulations.gov under Docket No. FAA–2023–1056 after the FAA final rule is published.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would affect 31 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD:

Estimated Costs for Required Actions

Labor cost	Parts cost	Cost per product	Cost on U.S. operators
56 work-hours × $85 per hour = $4,760	$0	$4,760	$147,560

The FAA estimates the following costs to do any necessary on-condition action that would be required based on the results of any required actions. The FAA has no way of determining the number of aircraft that might need this on-condition action:

Estimated Costs of On-Condition Actions

Labor cost	Parts cost	Cost per product
10 work-hours × $85 per hour = $850	$10	$860

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

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

[Amended]

2. The FAA amends § 39.13 by adding the following new airworthiness directive:

Airbus SAS: Docket No. FAA–2023–1056; Project Identifier MCAI–2023–00179–T.

(a) Comments Due Date

The FAA must receive comments on this airworthiness directive (AD) by July 17, 2023.

(b) Affected ADs

None.

(c) Applicability

This AD applies to Airbus SAS Model A350–941 and A350–1041 airplanes, certificated in any category, as identified in European Union Aviation Safety Agency (EASA) AD 2023–0026, dated January 30, 2023 (EASA AD 2023–0026).

(d) Subject

Air Transport Association (ATA) of America Code: 54, Nacelles/pylons.

(e) Unsafe Condition

This AD was prompted by reports that excessively deep spot faces on the front engine mounting bolt holes on the wing pylon were detected on the production line. The FAA is issuing this AD to address potential integration issues between the pylon and the front engine mount, which could lead to interference damage. The unsafe condition, if not addressed, could result in reduced fatigue life, which could adversely affect the structural integrity of the airplane.

(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 2023–0026.

(h) Exceptions to EASA AD 2023–0026

(1) Where EASA AD 2023–0026 refers to its effective date, this AD requires using the effective date of this AD.

(2) Where the applicability of EASA AD 2023–0026 refers to serial numbers, replace the text “the SBs, as defined in this AD” with “Airbus Service Bulletin A350–54–P006, Revision 1, dated December 20, 2022; and Airbus Service Bulletin A350–54–P008, dated December 20, 2022.”

(3) Where paragraph (2) of EASA AD 2023–0026 refers to “discrepancies,” for this AD discrepancies are any clash (interference) between the lockplate support and rib 1 or between the pylon bolt and the engine mount; damage (cracks, scratches, or erosion of the protective coating); and incorrect spot face depth or pylon thickness at the spot face.

(4) Where paragraph (2) of EASA AD 2023–0026 specifies to “contact Airbus for approved instructions for corrective action and accomplish those instructions accordingly” if discrepancies are detected; for this AD 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.”

(5) This AD does not adopt the “Remarks” section of EASA AD 2023–0026.

(6) Where the service information referenced in EASA AD 2023–0026 specifies to report inspection results or findings, this AD requires submitting information only if damage (cracks) or incorrect spot face depth or pylon thickness at the spot face are found during any inspection required by EASA AD 2023–0026. Operators are required to submit certain information as part of obtaining any corrective actions approved by Airbus SAS's European Aviation Safety Agency (EASA) Design Organization Approval (DOA).

(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 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 [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 2023–0026, dated January 30, 2023.

(ii) [Reserved]

(3) For EASA AD 2023–0026, 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 service information 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 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 [e-mail], or go to: www.archives.gov/​federal-register/​cfr/​ibr-locations.html.

Issued on May 25, 2023.

Michael Linegang,

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