Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain McDonnell Douglas Model DC-9-10, DC-9-20, DC-9-30, DC-9-40, and DC-9-50 series airplanes; and Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), DC-9-87 (MD-87), and MD-88 airplanes. This proposal would require replacement of the emergency power switch knob on the overhead switch panel in the flight compartment with a new, improved knob made of non-conductive material. This action is necessary to prevent the knob from conducting electricity, which could result in delivery of an electrical shock and consequent injury to flightcrew or maintenance personnel. This action is intended to address the identified unsafe condition.