Engineering Design for Rework of Lightning-Protection Plating on Carbon-Composite Military Airplane Parts

Lightning protection plating on military airplane carbon-composite parts is a process that requires careful handling of the final product, especially during maintenance of fuel, hydraulic, and electrical systems installations. This paper and the accompanying ten-minute videotape focus on the primary reasons for having to take special precautions with lightning-protection plating (especially low plating adhesion--between 1 and 2 pounds per inch-width) and the engineering rework procedures that have been developed to return damaged plating to the original configuration specified in the engineering drawing. Some of the important features of lightning-protection plating that have contributed to the virtual elimination of plating damage cases at Boeing are: (1) the application of nickel overplating to one-third of all plated parts; (2) edge sealing with two-part epoxy adhesives; (3) fillet sealing with polysulfide sealants [MIL-S-8802 (Ref. 1) or MIL-S-81733 (Ref. 2)], and (4) the installation of elastomeric protective removable equipment (PREs) to parts that have been plated in conformance with the engineering requirements.