Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Dornier Model 328-100 and -300 series airplanes. This proposal would require replacement of the screws in the aileron, rudder, and elevator trim tabs with new screws, and removal and re-installation of screws in the aileron, elevator and rudder trim tabs and the rudder spring tab, as applicable. This action is necessary to prevent reduced structural integrity of the screws in the aileron, elevator, and rudder trim tabs, and the rudder spring tab, due to countersinks that were not manufactured correctly, which could result in reduced controllability of the airplane. This action is intended to address the identified unsafe condition.