Summary
This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain McDonnell Douglas Model MD-11 series airplanes, that currently requires either the application of a vapor sealant on the back of the receptacle of the auxiliary power unit (APU) power feeder cable; or a one-time visual inspection for gold-plating and evidence of damage of the connector contacts of the power feeder cable of the APU generator, and various follow-on actions. This action would add a requirement for replacement of certain connector contacts (pins/sockets) with gold-plated contacts. This proposal is prompted by reports of burning and arcing of the connector contacts of the power feeder cable of the APU generator. The actions specified by the proposed AD are intended to reduce the potential for a fire hazard as a result of such burning or arcing.