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Since the 1960's, lightning protection of aircraft has been an important design aspect, a concern for the flying public, aircraft manufacturers and the Federal Aviation Administration (FAA). With the implementation of major aircraft structures fabricated from carbon fiber reinforced plastic (CFRP) materials, lightning protection has become a more complicated issue to solve. One widely used material for lightning strike protection of CFRP structures within the aerospace industry is expanded metal foil (EMF). EMF is currently used in both military and commercial passenger aircraft. An issue that has historically been an area of concern with EMF is micro cracking of paint on the composite structure which can result in corrosion of the metal foil and subsequent loss of conductivity. This paper addresses the issues of stress and displacement in the composite structure layup which contribute to paint cracking caused by aircraft thermal cycling.

The new combinations such as composites and titanium that are being used on today's new airplanes are proving to be very challenging when drilling holes during manufacturing and assembly operations. Gone are the days of hand drilling with high speed steel drills through soft aluminum structure, after which aluminum rivets would be swaged into those holes with very generous tolerances. The drilling processes today need to use cutter materials hard enough and tough enough to cut through hard metals such as titanium, yet be sharp enough to resistant abrasion and maintain size when drilling through composites. There is a constant search for better cutters and drills that can drill a greater number of holes. The cost of materials used in today's aircraft is much higher. The cutting tools are more expensive and the hole tolerances are much tighter.

The Boeing 787 Dreamliner will be the most fuel-efficient airliner in the world when it enters service in 2008. To help achieve this, Boeing will utilize state-of-the-art carbon fiber for primary structures. Advanced manufacturing techniques and processes will be used in the assembly of large composite structures. Electroimpact has proposed a system utilizing the low recoil Low Voltage Electromagnetic Riveter (LVER) to drill and install bolts. A test program was initiated between Boeing Materials Process and Engineering (MP&E) and Electroimpact to validate the LVER process for swaging titanium collars on titanium pins in composite material. This paper details the results of these tests.

A new automated production system for installation of Lightweight Groove Proportioned (LGP) and Hi-Lock bolts in wing panels has been implemented in the Boeing 737 wing manufacturing facility in Renton, Washington. The system inserts LGP and Hi-Lok bolts into interference holes using a ball screw mechanical squeeze process supported by a back side rod-locked pneumatic clamp cylinder. Collars are fed and loaded onto a swage die retaining pin, and swaging is performed through ball screw mechanical squeeze. Offset and straight collar tools allow the machine to access 99.9% of fasteners in 3/16″, ¼″ and 5/16″ diameters. Collar stripping forces are resolved using a dynamic ram inertial technique that reduces the pull on the work piece. Titanium TN nuts are fed and loaded into a socket with a retaining spring, and installed on Hi-Loks Hi-Lok with a Bosch right angle nut runner.