Integral Lightning Strike Protection of CFC Fuel Tanks on Aircraft

The external structure of fast jet aircraft are now often constructed largely from Carbon Fibre Composites (CFC). Much of the external skins form part of fuel tanks. A lightning strike to a tank skin is likely to cause arcing and sparking at structural joints. This can lead to particles of molten metal or resin being injected into the fuel tanks along with hot gasses which presents a risk of fuel explosion.

This paper describes lightning strike protection of CFC fuel tanks with emphasis on integral lightning strike protection and the protection of access panels.

This integral protection is based on a network of copper strips co-bonded into the composite tank shell. The protection details, such as foil thickness and fastener installation details may be varied to suit the lightning strike threat. The details are specified in BAE SYSTEMS patents Ref. 1.