Plain English Meaning

Aircraft are built so that if lightning hits them, the electricity flows around the outside of the airframe and exits without harming the people, fuel, or systems inside.

Full Definition

The set of design features and materials built into an aircraft's structure, wiring, and fuel system to safely conduct the electrical energy of a lightning strike across the airframe and back out into the atmosphere without damaging critical systems, igniting fuel, or injuring occupants. In metal aircraft, the conductive skin itself carries most of the current; in composite aircraft, embedded conductive layers (such as metal mesh, , or expanded metal screens) are added because do not conduct electricity well on their own.