Airworthiness Directives; MHI RJ Aviation ULC (Type Certificate Previously Held by Bombardier, Inc.) Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain MHI RJ Aviation ULC Model CL-600-2D24 (Regional Jet Series 900) airplanes. This AD was prompted by a report of a manufacturing error that can create dents on the lower wing plank, close to the flap arm locations at certain wing stations; as a result, cracks could develop and weaken the structural integrity of the wings before being detected by any existing required inspections. This AD requires an inspection for damage (including dents, cracks, discoloration, gouges, scratches, or other surface damage) of the lower wing plank in the flap arm areas at certain wing stations, and repair if necessary. The FAA is issuing this AD to address the unsafe condition on these products.