Airworthiness Directives; 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 amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas 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 amendment requires 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. The actions specified by this AD are intended 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.