Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all Bombardier Model DHC-8-101, - 102, -103, -106, -201, -202, -301, -311, and -315 series airplanes. This proposal would require repetitive detailed visual inspections and high frequency eddy current inspections to detect cracking of the wing upper skin and ladder plates at over wing access panels between certain stations; and repair, if necessary. This proposal is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by the proposed AD are intended to detect and correct fatigue cracking of the wing ladder plates, which, if not corrected, could reduce the structural integrity of the wing.