Transport Canada CF-2023-42

Requires inspections of both the left-hand side and right-hand side inboard flap seal plate assembly attaching angles for cracks, and, subsequently, the replacement of both existing inboard flap seal plate assemblies with improved components. This AD stems from multiple reports in service of missing or damaged inboard flap seal plate assemblies. An investigation revealed a premature fatigue failure mode of the seal plate assembly. Left uncorrected, the flap seal plate may partially or totally detach. Under certain flight conditions, a missing flap seal plate assembly could lead to excessive buffeting and vibration, and consequent damage to the airplane.