AD 2024-05-08

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.

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 888-663-3639; email TC.AirworthinessDirectives-Consignesdenavigabilite.TC@tc.gc.ca; 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.

Gabriel Kim, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7300; email 9-avs-nyaco-cos@faa.gov.

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.

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.

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.

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.

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.

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

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.

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.

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.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

1. The authority citation for part 39 continues to read as follows:

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