AD FAA-2017-0867

We are adopting a new airworthiness directive (AD) for all Viking Air Limited Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III airplanes. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as cracking found in the wing rear spar web at the wing station where the flap outboard hinge is attached. We are issuing this AD to require actions to address the unsafe condition on these products.