Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain McDonnell Douglas Model DC-9-81, -82, -83, and -87 series airplanes, and Model MD-88 airplanes. This proposal would require a detailed visual inspection of certain wires to detect chafing and preload; repair, if necessary; and modification of certain wire assemblies. This action is necessary to prevent insufficient clearance between wire assemblies and the ice protection airduct and airstair door interlock rod, chafing, and consequent arcing of wire assemblies. Such arcing could result in damage to electronic equipment and adjacent structure, or cause the insulation blankets to ignite, which could result in smoke and fire in the flight deck and main cabin. This action is intended to address the identified unsafe condition.