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 us e on an aircraft engine nacelle to achieve hybrid laminar flow. The work wa s carried out under a European Commission program HYLDA (Hybrid Laminar Flo w Demonstration on Aircraft). Hybrid laminar flow is a combination of natur al laminar flow achieved by aerodynamic profiling and leading edge suction through the perforated surface. The carbon fiber panels were perforated usi ng an Nd-YAG laser. The specimens were subjected to simulated zone 2A and 1 C lightning strikes and the results are compared to similar tests on non-pe rforated and painted specimens. It was found that the visible damage was le ss on the perforated specimens compared to the other two. This is presumed to be due to the lightning are attaching to the fiber ends in the holes, an d thus being spread over a larger area.