AD 2026-14-10

This AD is effective August 18, 2026.

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2026-7217; 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.

Soban Saeed, Aviation Safety Engineer, FAA, 1801 South Airport Road, Wichita, KS 67209; phone: (316) 946-4123; email: CCB-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 Textron Aviation Inc., Model 408 airplanes. The NPRM was published in the Federal Register on April 29, 2026 (91 FR 23023). The NPRM was prompted by a report from Textron Aviation Inc., that an undetected crack could develop in the horizontal and vertical stabilizers forward and aft spars on certain Model 408 airplanes due to a quality escape from the supplier during manufacturing. The NPRM was further prompted by the manufacturer's revision of the AMM to introduce a detailed inspection for the horizontal stabilizer spar, and a revision to the airplane serial effectivity for the vertical stabilizer spar detailed inspection. In the NPRM, the FAA proposed to require revising the ALS of the existing AMM or ICA and the existing approved maintenance or inspection program, as applicable.

The unsafe condition, if not addressed, could result in reduced structural integrity of the airplane or reduced controllability of the airplane with possible loss of control of the airplane. The FAA is issuing this AD to address the unsafe condition on these products.

The FAA received no comments on the NPRM or on the determination of the costs.

The FAA reviewed the relevant data, considered any 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 these products. Except for minor editorial changes, this AD is adopted as proposed in the NPRM. None of the changes will increase the economic burden on any operator.

The FAA estimates that this AD affects 28 airplanes of U.S. registry.

The FAA estimates the following costs to comply with this AD:

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: