Summary
This document proposes the supersedure of an existing airworthiness directive (AD), applicable to all Short Brothers Model SD3-60 SHERPA series airplanes, that currently requires a one-time visual inspection to determine the part number of the power control cable assemblies and pulleys of the engine controls; and replacement of the power control cable assemblies and pulleys (as applicable) with new parts, if necessary. This action would require accomplishment of the inspection and replacement in accordance with revised procedures. This proposal is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by the proposed AD are intended to prevent breakage of the power control cable assemblies due to the inflexible construction of the cable, which could result in loss of engine power and consequent reduced controllability of the airplane.