Airworthiness Directives; McDonnell Douglas Model MD-11 Series Airplanes

This document published in the Federal Register an amendment adopting airworthiness directive (AD) 99-08-51 that was sent previously to all known U.S. owners and operators of certain McDonnell Douglas Model MD-11 series airplanes by individual notices. This AD requires visual inspections under the floorboards in the lower center cargo compartment at frame 1681 to verify that a certain bracket and a certain open face nylon clamp are installed to a specific support wire bundle and to detect damage of the subject wire bundle; repair of damaged wiring; and installation of certain silicone rubber coated with a glass cloth protective wrap around the wire bundle, if necessary. This action is prompted by an incident in which the insulation blanket between frames 1661 and 1681 in the lower center cargo compartment was found to be burnt due to a missing wiring harness support bracket/clamp on the wire bundle at frame 1681. The actions specified by this AD are intended to ensure that such a wire harness support bracket/clamp is installed; a missing bracket/clamp could cause the wire bundle to chafe against the frame, which could result in sparks, smoke, and possible fire in the lower center cargo compartment.