Action
Final rule.
Summary
We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc. Model DHC-8-400 series airplanes. This AD was prompted by a determination by the manufacturer that shims might not have been installed between certain longerons and longeron joint fittings. This AD requires various repetitive and detailed visual inspections of the affected areas and corrective actions if necessary. This AD also provides terminating action for certain repetitive inspections. We are issuing this AD to address the unsafe condition on these products.