AD 2018-21-02 83 FR 53567

We are adopting a new airworthiness directive (AD) for Viking Air Limited Model DHC-3 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 pitting corrosion on the shank of the wing strut attach bolts. We are issuing this AD to require actions to address the unsafe condition on these products.