AD FAA-2026-3870

The FAA proposes to adopt a new airworthiness directive (AD) for certain Textron Aviation, Inc., Model 408 airplanes. This proposed AD was prompted by the manufacturer's revision of the aircraft maintenance manual (AMM) to add a detailed inspection for the horizontal stabilizer spar, and change the airplane serial effectivity for the vertical stabilizer spar detailed inspection. This proposed AD would require revising the Airworthiness Limitations Section (ALS) of the existing AMM or instructions for continued airworthiness (ICA) and the existing approved maintenance or inspection program, as applicable. The FAA is proposing this AD to address the unsafe condition on these products.