How does lightning impact a composite airliner like the Boeing 787. Images from an American airlines incident. Other 787s have have similar damage including a Jetstar 787 that suffered burn marks and dozens of small holes punctured on the underside of the fuselage
It is not uncommon for an aircraft to be hit by lightning once or twice a year. After the aircraft lands, an inspection must always be performed to assess the state of the aircraft prior to return to service.
What makes the Boeing 787 different is that it uses more composite materials such as carbon fibers. These materials are less conductive than aluminum, which causes more damage to the surface in the event of a lightning strike.
Back in testing the 787 flight test team gathered data after one of the 787 test aircaft was struck by lightning. Unlike traditional aluminum aircraft where the entire aircraft is conductive, on a composite airplane the charge from a lightning strike would find its way to the conductive parts such as wiring or hinges. In order to avoid the risk of the charge damaging these kinds of parts, Boeing had to add conductive material to the composites in order to provide a pathway for lightning strikes.
The added weight to protect the aeroplane from lightning strikes ended up being more than Boeing anticipated. The material was one of the factors that pushed the Dreamliner past its target weight earlier in the development process.
Source – Airline Secret Exposed Page