Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all Fokker Model F27 Mark 100, 200, 300, 400, 500, 600, and 700 series airplanes. This proposal would require replacement of certain rudder horn assemblies with a new assembly. For certain airplanes, the proposed AD also would require replacement of certain rudder control rods with a new rod. This proposal is prompted by reports of cracked rudder horns and a cracked rudder control rod, caused by impact overload. The actions specified by the proposed AD are intended to prevent such an overload and consequent cracking of the subject parts, which could result in reduced structural integrity of the rudder horn assembly or loss of rudder control; this condition could lead to reduced controllability of the airplane.