Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 747, 757, 767, and 777 series airplanes. This proposal would require modification of certain drip shields located on the flight deck, and follow-on actions. This action is necessary to prevent potential ignition of the moisture barrier cover of the drip shield, which could propagate a small fire that results from an otherwise harmless electrical arc, leading to a larger fire. This action is intended to address the identified unsafe condition.