Summary
This document proposes to revise an existing airworthiness directive (AD), applicable to certain Raytheon Model BAe.125, DH.125, BH.125, and HS.125 series airplanes, that currently requires inspection of the elevator mass balance side plate assembly and spigot for corrosion, and repair, if necessary; application of corrosion protection treatment; and installation of corrosion resistant Monel rivets in the elevator balance weight structure. That AD was prompted by reports of corrosion on the elevator mass balance side plate assembly and the balance weight spigot. The actions specified by that AD are intended to prevent such corrosion damage, which could lead to displacement of the side plate and consequent control surface interference and jamming of flight controls. This action would limit the applicability of the existing AD.