What happens when aircrafts are hit by lightning?

The thought of 1 billion joules of energy striking your airplane while you are trapped ten kilometres above the ground is the stuff of nightmares. But is it really as scary as it sounds?

It turns out that airplanes are pretty well-protected against lightning strikes and they no longer cause planes to crash. Though it is estimated that the average commercial plane gets struck once a year, the last plane crash caused by lightning was in 1967. This catastrophic accident killed all 81 crew and passengers on board after the lightning struck the fuel tank and caused a colossal explosion.

Since then engineers have made huge changes in plane designs and have enforced discharge and grounding precautions. Fuel has been refined so its vapours are less explosive, and fuel systems are well shielded to prevent sparks and resist burns. Modern planes are designed so that the electricity will be dissipated across the fuselage’s surface if hit, in a process known as the skin effect.

This will happen naturally with planes built from aluminium, while crafts made from composite materials are constructed with a conductive mesh. This means there is usually no evidence that the plane was ever hit.