Summary
This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Bombardier Model DHC-8-200 and -300 series airplanes, that currently requires repetitive inspections to detect chafing or arcing damage to the cable/wire and fuel tube assemblies on the right-hand side of each engine, and replacement with new components, if necessary. That AD also provides for an optional terminating action for the repetitive inspections required by that AD. This proposal would require accomplishment of the previously optional terminating action. This action is necessary to prevent chafing of the cable/wire bundles against the fuel line, which could result in arcing and a consequent fire or explosion. This action is intended to address the identified unsafe condition.