Summary
This document revises an earlier proposed airworthiness directive (AD), applicable to certain McDonnell Douglas Model MD-11 and DC-10 series airplanes, and KC-10A (military) airplanes. That action would have superseded a previously issued AD that currently requires functional testing to verify proper installation of the electrical connectors to the engine generator and fire bell shutoff switches, and correction of the installation, if necessary. The previous proposal would have added a requirement to install tethers on the electrical connectors to the engine generator and fire bell shutoff switches, which would terminate the required repetitive functional tests. That proposal was prompted by the development of a modification that minimizes the possibility of improperly connecting (crossing) the electrical connectors to the fire extinguishing handles. The actions specified by that proposal were intended to prevent the wrong engine- driven generator from being shut down unnecessarily in the event of an engine fire warning. This new action revises the proposed rule by including additional actions as part of the terminating modification for certain airplanes.