Lightning Strike of Perforated Carbon Fiber Epoxy Laminar Flow Panels

The effect of lightning on a perforated carbon fiber composite is examined in this technical note. This perforated material has been considered for use on an aircraft engine nacelle to achieve hybrid laminar flow. The work was carried out under a European Commission program HYLDA (Hybrid Laminar Flow Demonstration on Aircraft). Hybrid laminar flow is a combination of natural laminar flow achieved by aerodynamic profiling and leading edge suction through the perforated surface. The carbon fiber panels were perforated using an Nd-YAG laser. The specimens were subjected to simulated zone 2A and 1C lightning strikes and the results are compared to similar tests on non-perforated and painted specimens. It was found that the visible damage was less on the perforated specimens compared to the other two. This is presumed to be due to the lightning arc attaching to the fiber ends in the holes, and thus being spread over a larger area.