2020-28861. Airworthiness Directives; Airbus SAS Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (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 that during the assembly of a certain section of the fuselage, the gaps found on self-aligning nuts for eight fasteners were out of tolerance. This AD requires a rotating probe test of all fastener holes located in the affected area for any discrepancies, an eddy current inspection of the surrounding flange for any discrepancies, a detailed inspection of certain frames for any discrepancies, and corrective actions if necessary, as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. The FAA is issuing this AD to address the unsafe condition on these products.

DATES:

This AD is effective February 3, 2021.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of February 3, 2021.

ADDRESSES:

For material incorporated by reference (IBR) in this AD, contact the EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone [phone]; email [e-mail]; internet www.easa.europa.eu. You may find this IBR material on the EASA website at https://ad.easa.europa.eu. You may view this IBR 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 on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-0681.

Examining the AD Docket

You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-0681; 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, 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.

FOR FURTHER INFORMATION CONTACT:

Kathleen Arrigotti, Aerospace Engineer, Large Aircraft Section, International Validation Branch, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone and fax [phone]; email [e-mail].

SUPPLEMENTARY INFORMATION:

Discussion

The EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2020-0109, dated May 15, 2020 (EASA AD 2020-0109) (also referred to as the Mandatory Continuing Airworthiness Information, or the MCAI), to correct an unsafe condition for certain Airbus SAS Model A350-941 airplanes.

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 August 4, 2020 (85 FR 47122). The NPRM was prompted by a report that during the assembly of the section 19 skin to frame (FR) 98 joint of the fuselage, the gaps found on self-aligning nuts for eight fasteners were out of tolerance. The NPRM proposed to require a rotating probe test of all fastener holes located in the affected area for any discrepancies, an eddy current inspection of the surrounding flange for any discrepancies, a detailed inspection of certain frames for any discrepancies, and corrective actions if necessary, as specified in an EASA AD.

The FAA is issuing this AD to address gaps that are out of tolerance, which could reduce the fatigue and damage tolerance properties of the affected area, and possibly affect the structural integrity of the rear cone of the fuselage. See the MCAI for additional background information.

Comments

The FAA gave the public the opportunity to participate in developing this final rule. The following presents the comments received on the NPRM and the FAA's response to each comment.

Request To Revise the Proposed Applicability

Delta Air Lines, Inc. (DAL) requested that the FAA revise the applicability in the NPRM. DAL stated that the applicability should reflect the effectivity specified in Airbus Service Bulletin A350-53-P057, dated February 21, 2020, and not what is specified in the NPRM and in EASA AD 2020-0109. DAL also stated that the NPRM and EASA AD 2020-0109 would require operators the unnecessary burden of reviewing records and updating associated paperwork to ensure and prove that the proper modification status is embodied on all airplanes, including on any Model A350 airplanes delivered in the future, despite the embodiment of the applicable modification in production. DAL commented that Airbus Service Bulletin A350-53-P057, dated February 21, 2020, specifies specific manufacturer serial numbers and describes which airplanes will have the modification embodied in production (manufacturer serial number 0307 and subsequent).

The FAA disagrees with the request. The applicability of this AD (and EASA AD 2020-0109) excludes any airplanes on which the modification has been embodied, whether during or after production. EASA, as the State of Design Authority for Airbus products, has determined that this applicability is appropriate because it includes any airplanes on which the modification was not embodied, while excluding those on which the modification has been embodied. The FAA agrees with this decision because it ensures the unsafe condition is addressed on all applicable airplanes. The FAA has not changed the AD in this regard.

Request To Include Exception To Provide Correct Reference for Installing New Fasteners

DAL requested that the NPRM be revised to address a discrepancy in a manual reference for installing the new fasteners. DAL noted that Airbus Service Bulletin A350-53-P057, dated February 21, 2020, specifies Airbus task A350-A-53-XX-P057-01001-720A-A and task A350-A-53-XX-P057-02001-720A-A for instructions to install the new fasteners, and that the actions in those tasks are considered Required for Compliance (RC). DAL asserted that the instructions in those tasks should refer to the Airbus A350 Aircraft Maintenance Manual (AMM) procedure rather than the aircraft structural repair (ASR) manual. DAL pointed out that there is no existing ASR manual with chapter A350-A-20-51-50-01ZZZ-25BZ-A; however, the AMM reference for standard mechanical torques is maintenance procedure chapter A350-A-20-51-50-01ZZZ-25BZ-A. DAL stated that Airbus has confirmed in Airbus Technical Request Dossier 80808465 that the correct reference is to the AMM. DAL further requested that, if this discrepancy is not addressed in the AD, it will require that a global alternative method of compliance (AMOC) be requested by Airbus.

The FAA agrees that the correct document should be referenced for the reasons provided above. The FAA has added paragraph (h)(3) in this AD to clarify that, where Airbus Service Bulletin A350-53-P057, dated February 21, 2020, specifies Airbus task A350-A-53-XX-P057-01001-720A-A and task A350-A-53-XX-P057-02001-720A-A, for instructions for installing the new fasteners, and those instructions specify to refer to “Ref. ASR A350-A-20-51-01ZZZ-25BZ-A,” for the purposes of this AD, the correct reference is “Ref. AMM Maintenance Procedure A350-A-20-51-01ZZZ-25BZ-A.”

Request To Provide Clarification on the Use of Substitute Fasteners

DAL requested that the FAA provide clarification regarding the use of substitute fasteners. DAL stated that task A350-A-53-XX-P057-01001-720A-A and task A350-A-53-XX-P057-02001-720A-A, specified in Airbus Service Bulletin A350-53-P057, dated February 21, 2020, provide instructions to install new fasteners. DAL also stated that standard notes within these allow for the use of washers or approved substitute fasteners should the installed fasteners not be sufficient per the standards provided in the ASR manual. DAL questioned whether, since Airbus Service Bulletin A350-53-P057, dated February 21, 2020, provides the specific fasteners to use to address the issue in the NPRM, an AMOC will be required for the use of substitute fasteners despite these notes.

The FAA agrees to provide clarification. An AMOC is not needed for the use of washers or approved substitute fasteners should the installed fasteners not be sufficient. The FAA has not changed this AD in this regard.

Conclusion

The FAA reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this final rule with the change described previously and minor editorial changes. The FAA has determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM for addressing the unsafe condition; and
• Do not add any additional burden upon the public than was already proposed in the NPRM.

The FAA also determined that this change will not increase the economic burden on any operator or increase the scope of this final rule.

Related Service Information Under 1 CFR Part 51

EASA AD 2020-0109 describes procedures for a rotating probe test of all fastener holes located in the affected area for any discrepancies (i.e., cracking or damage), an eddy current inspection of the surrounding flange for any discrepancies, a detailed inspection of FR 97 to FR 99 for any discrepancies, and corrective actions if necessary. Corrective actions include replacing all fasteners located in the affected area with new bolts and self-aligning nuts, 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 the ADDRESSES section.

Costs of Compliance

The FAA estimates that this AD affects 13 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
1 work-hour × $85 per hour = $85	$0	$85	$1,105

The FAA estimates the following costs to do any necessary on-condition replacements 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 these replacements:

Estimated Costs of On-Condition Actions *

Labor cost	Parts cost	Cost per product
6 work-hours × $85 per hour = $510	$70	$580
* The FAA has received no definitive data that would enable providing cost estimates for the on-condition repairs specified in this AD.

According to the manufacturer, some or all of the costs of this AD may be covered under warranty, thereby reducing the cost impact on affected operators. The FAA does not control warranty coverage for affected operators. As a result, the FAA has included all known costs in the cost estimate.

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

Adoption of 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:

2020-26-21 Airbus SAS: Amendment 39-21376; Docket No. FAA-2020-0681; Product Identifier 2020-NM-089-AD.

(a) Effective Date

This AD is effective February 3, 2021.

(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 2020-0109, dated May 15, 2020 (EASA AD 2020-0109).

(d) Subject

Air Transport Association (ATA) of America Code 53, Fuselage.

(e) Reason

This AD was prompted by a report that during the assembly of the section 19 skin to frame (FR) 98 joint of the fuselage, the gaps found on self-aligning nuts for eight fasteners were out of tolerance. The FAA is issuing this AD to address gaps that are out of tolerance, which could reduce the fatigue and damage tolerance properties of the affected area, and possibly affect the structural integrity of the rear cone of the fuselage.

(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 2020-0109.

(h) Exceptions to EASA AD 2020-0109

(1) The “Remarks” section of EASA AD 2020-0109 does not apply to this AD.

(2) Where paragraph (2) of EASA AD 2020-0109 specifies actions if “any discrepancy is detected, as defined in the SB,” for this AD a discrepancy is defined as any crack or damage.

(3) Where Airbus Service Bulletin A350-53-P057, dated February 21, 2020 (referenced in EASA AD 2020-0109), specifies Airbus task A350-A-53-XX-P057-01001-720A-A and task A350-A-53-XX-P057-02001-720A-A, for instructions for installing the new fasteners, and those instructions specify to refer to “ASR A350-A-20-51-01ZZZ-25BZ-A,” for the purposes of this AD, the correct reference is “AMM Maintenance Procedure A350-A-20-51-01ZZZ-25BZ-A.”

(i) Other FAA AD Provisions

The following provisions also apply to this AD:

(1) Alternative Methods of Compliance (AMOCs): The Manager, Large Aircraft Section, 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 Large Aircraft Section, 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, Large Aircraft Section, 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 paragraphs (h)(2) and (3) and 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) Related Information

For more information about this AD, contact Kathleen Arrigotti, Aerospace Engineer, Large Aircraft Section, International Validation Branch, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone and fax [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 2020-0109, dated May 15, 2020.

(ii) [Reserved]

(3) For EASA AD 2020-0109, contact the EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone [phone]; email [e-mail]; internet www.easa.europa.eu. You may find this EASA AD on the EASA website at https://ad.easa.europa.eu.

(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. This material may be found in the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-0681.

(5) You may view this material 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: https://www.archives.gov/​federal-register/​cfr/​ibr-locations.html.

Issued on December 17, 2020.

Lance T. Gant,

Director, Compliance & Airworthiness Division, Aircraft Certification Service.