Lightning tolerance test. A researcher holding two carbon-fiber panels from a helicopter, showing their tolerance of lightning. The panel at right is simple carbon fiber, and has had a large hole punched in it by simulated lightning. This is because it is an electrical insulator, so cannot disperse the electricity across its surface. The panel at left has a thin grid of copper wire coating the surface. This allows the electrical charge to disperse over the surface, causing nothing more than damage to the paint. Photographed at Lightning Technologies Inc. of Massachusetts, USA. 1992.MODEL RELEASED