Composite1.1
Lightning Protection for Composites – Past, Present and Future
Arlene M. Brown Technical Fellow, The Boeing Company
As the percentage of organic composites has increased in products, the need for both low cost and lightweight lightning protection has significantly increased. Although this focuses on aerospace applications, it also recognizes that wind power and automotive industries are some of the other areas with an increased interest in lightning protection. For decades, lightning protection systems for composites have continued to improve as they progressed from products such as exterior flame sprays and metalized prepregs to co-cured woven metal and perforated metal foils. Another form, interwoven metal wires in carbon fabric, is one of the few types that can provide structural benefit without increasing manufacturing time. There are many factors considered when designing and qualifying a protection system. Durability was one the most challenging targets to meet for aircraft applications such as the 777 in the 1990’s and was also a significant consideration for the new 787. In the future durability will remain significant but the importance of other factors may shift. Will Occupational Safety and Health Administration (OSHA) considerations be a major discriminator between emerging nanotechnology systems? From a logistics perspective, is a secondary operation such as conductive appliqué or a conductive coating preferred over a co-cured solution? If a product offers multifunctional benefits, what architectural changes are needed to capitalize on those benefits? What analyses and tests exist, or need to be developed, to predict service life of a novel product? These are just some of the questions that require answers to successfully transition a product to production. Answers to these types of questions will determine if emerging technologies will revolutionize lightning protection or only be used in niche applications. Copyright © 2012 Boeing. All rights reserved