2024-08103. Airworthiness Directives; Airbus Canada Limited Partnership (Type Certificate Previously Held by C Series Aircraft Limited Partnership (CSALP); Bombardier, Inc.) Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for certain Airbus Canada Limited Partnership Model BD-500-1A10 and BD-500-1A11 airplanes. This AD was prompted by a report of a fouling condition (interference) between the gimbal bushing and the airplane horizontal stabilizer trim actuator (HSTA) structural fitting, which prevented engagement of the secondary load path. This AD requires replacing the upper gimbal bushing flanges, as specified in a Transport Canada 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 May 22, 2024.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of May 22, 2024.

ADDRESSES:

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2023-1818; 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 material incorporated by reference in this AD, contact Transport Canada, Transport Canada National Aircraft Certification, 159 Cleopatra Drive, Nepean, Ontario K1A 0N5, Canada; telephone [phone]; email [e-mail]; website tc.canada.ca/en/aviation.

• 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-2023-1818.

FOR FURTHER INFORMATION CONTACT:

Gabriel Kim, 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 Canada Limited Partnership Model BD-500-1A10 and BD-500-1A11 airplanes. The NPRM published in the Federal Register on September 6, 2023 (88 FR 60901). The NPRM was prompted by AD CF-2023-23, dated April 5, 2023 (Transport Canada AD CF-2023-23) (also referred to as the MCAI), issued by Transport Canada, which is the aviation authority for Canada. The MCAI states that interference was found between the gimbal bushing and the airplane HSTA structural fitting, which prevented engagement of the secondary load path. On multiple other Model BD-500-1A10 and BD-500-1A11 airplanes, similar interference caused visible damage, but the secondary load path was successfully engaged. Inability to engage the HSTA secondary load path, following a failure of the primary load path, may result in a loss of pitch control of the airplane.

In the NPRM, the FAA proposed to require replacing the upper gimbal bushing flanges, as specified in Transport Canada AD CF-2023-23. The FAA is issuing 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-2023-1818.

Discussion of Final Airworthiness Directive

Comments

The FAA received comments from Air Line Pilots Association, International (ALPA), who supported the NPRM without change.

The FAA received additional comments from Delta Air Lines (DAL). The following presents the comment received on the NPRM and the FAA's response.

Request To Add Exception To Address Discrepancies in Service Information

DAL requested that an exception be added in the proposed AD to address a part number discrepancy in the service information specified in Transport Canada AD CF-2023-23. The commenter stated that the part number of the pre-modified upper gimbal ring assembly given in the service information is incorrect and should be corrected from part number (P/N) 490740-103 to P/N 490740-101.

The FAA agrees with the requested change. The manufacturer has confirmed that the part number of the pre-modified upper gimbal ring assembly, as specified in the service information referenced in Transport Canada AD CF-2023-23, is incorrect and verified that the new part number specified by the commenter is correct. A new exception has been added to paragraph (h) of this AD to provide this correction.

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 comments 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

Transport Canada AD CF-2023-23 specifies procedures for replacing the upper gimbal bushing flanges. 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.

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 24 work-hours × $85 per hour = $2,040	$5,883	Up to $7,923	Up to $31,692

The FAA has included all known costs in its cost estimate. According to the manufacturer, however, some or all of the costs of this 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

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:

2024-05-08 Airbus Canada Limited Partnership (Type Certificate Previously Held by C Series Aircraft Limited Partnership (CSALP); Bombardier, Inc.): Amendment 39-22699; Docket No. FAA-2023-1818; Project Identifier MCAI-2023-00582-T.

(a) Effective Date

This airworthiness directive (AD) is effective May 22, 2024.

(b) Affected ADs

None.

(c) Applicability

This AD applies to Airbus Canada Limited Partnership (Type Certificate previously held by C Series Aircraft Limited Partnership (CSALP); Bombardier, Inc.) Model BD-500-1A10 and BD-500-1A11 airplanes, certificated in any category, as identified in Transport Canada AD CF-2023-23, dated April 5, 2023 (Transport Canada AD CF-2023-23).

(d) Subject

Air Transport Association (ATA) of America Code: 27, Flight Controls.

(e) Unsafe Condition

This AD was prompted by a report of interference between the gimbal bushing and the airplane horizontal stabilizer trim actuator (HSTA) structural fitting. The FAA is issuing this AD to ensure no interference occurs between the bushing and HSTA. The unsafe condition, if not addressed, could result in the inability of the HSTA secondary load path to engage, following a failure of the primary load path, which may result in a loss of pitch control 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, Transport Canada AD CF-2023-23.

(h) Exceptions to Transport Canada AD CF-2023-23

(1) Where Transport Canada AD CF-2023-23 refers to its effective date, this AD requires using the effective date of this AD.

(2) Where Transport Canada AD CF-2023-23 refers to hours air time, this AD requires using flight hours.

(3) Where the service information referenced in Transport Canada AD CF-2023-23 refers to the pre-modified upper gimbal ring assembly as part number “490740-103,” this AD requires replacing that number with “490740-101.”

(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 Transport Canada; or Airbus Canada Limited Partnership's Transport Canada Design Approval Organization (DAO). If approved by the DAO, the approval must include the DAO-authorized signature.

(j) Additional Information

For more information about this AD, contact Gabriel Kim, 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) Transport Canada AD CF-2023-23, dated April 5, 2023.

(ii) [Reserved]

(3) For Transport Canada AD CF-2023-23, contact Transport Canada, Transport Canada National Aircraft Certification, 159 Cleopatra Drive, Nepean, Ontario K1A 0N5, Canada; telephone [phone]; email [e-mail]; website tc.canada.ca/en/aviation.

(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 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 March 4, 2024.

Victor Wicklund,

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