Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all Raytheon Model DH 125-1A, -3A, and -400A series airplanes. This proposal would require a one-time inspection to detect scoring of the upper fuselage skin around the periphery of the cockpit canopy blister interface, and repair, if necessary. This proposal is prompted by reports indicating that scoring of the upper fuselage skin had been detected in that area. The actions specified by the proposed AD are intended to detect and correct scoring of the upper fuselage skin around the periphery of the cockpit canopy blister interface, which could result in reduced structural integrity of the fuselage, and consequent cabin depressurization.