Summary
This document proposes the supersedure of two existing airworthiness directives (AD), applicable to certain McDonnell Douglas Model MD-11 series airplanes, that currently require inspections in the lower center cargo compartment at frame 1681 to verify that a certain bracket and a certain open face nylon clamp were installed to a specific wire bundle support and to detect damage of the subject wire bundle; and corrective actions, if necessary. Those AD's were prompted by an incident in which the insulation blanket in the lower center cargo compartment was found to be burnt due to a missing wiring harness support bracket/clamp on a wire bundle. This action would require a similar inspection and corrective actions required by the existing AD's and would remove certain airplanes from the applicability of the existing AD's. This action also would add a requirement to install a wire assembly support bracket, clamp, and spacer, or revise the wire assembly support bracket and clamp installation; as applicable. The actions specified by the proposed AD are intended to prevent sparks, smoke, and possible fire in the lower center cargo compartment.