Aircraft are becoming increasingly more reliant upon lightweight composite products and systems in order to improve fuel efficiency, longevity and cost. When designing a new wide-body aircraft, an aircraft manufacturer wanted to bring together the very latest advanced composite technology to achieve these benefits; this included manufacturing the wings entirely out of composites rather than aluminium.
Traditionally, the wings of an aircraft and the fuel pipes within them are both made of aluminium; therefore if lightning were to strike, the wings would conduct the electricity and dissipate it, avoiding the metal fuel pipes and the risk of explosion. The problem for the manufacturer was that carbon fibre composites have a much lower electrical conductivity than aluminium, therefore it cannot easily dissipate electrical charges and so lightning could cause a problem. The manufacturer clearly faced a challenge.
CTG had previously developed composite fuel pipes within the automotive market and saw an opportunity to transfer this technology across to aerospace fuel pipes. CTG’s filament wound fuel pipes are made of glass fibre composites because they can be designed to have tuneable resistance, i.e. they can be highly conductive to highly resistive.
This means they can resist lightning strike electrical surges and dissipate static build up from fuel movement; essential for aircraft safety and ensuring the manufacturer can keep their weight saving composite wings. Another innovation when designing the pipes was the use of O-rings. Each fuel pipe ‘floats’ on O-rings so that when the aircraft wings bend the pipes can move with it rather than getting damaged or breaking. CTG fuel pipes are scalable which means a reduced part count, adding additional weight savings and further improving fuel efficiency and cost.