Airworthiness Directives; British Aerospace Model BAe 146 and Model Avro 146-RJ Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to certain British Aerospace Model BAe 146 and Model Avro 146-RJ airplanes. This action requires modification of the left- and right-hand elevators to improve water drainage. This amendment is prompted by reports that elevator oscillations and resultant airplane pitch oscillations have occurred due to the elevator balance changes as a result of accumulation of water in the elevators. The actions specified in this AD are intended to minimize accumulation of water in the elevators, which could lead to elevator and airplane pitch oscillations with a subsequent reduction of controllability of the airplane and damage to the tail surface structure.