Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all CASA Model CN-235, CN-235-100, and CN-235-200 series airplanes. This proposal would require replacing the upper brackets in frames 33, 34, and 35, with improved brackets that are more fatigue resistant, and reinforcing frame 35. This action is necessary to prevent fatigue cracking in the zone of the fittings connecting the fuselage to stiffener rods located in frames 33, 34, and 35, which could result in reduced structural integrity of the airplane. This action is intended to address the identified unsafe condition.