Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Bombardier Model CL-600-2B19 series airplanes. This proposal would require repetitive inspections for cracking of the left and right lower wing planks, and repair, if necessary. This action is necessary to find and fix such cracking, which could result in reduced structural integrity of the wing. This action is intended to address the identified unsafe condition.