Flight explained
What happens when lightning strikes an aircraft
How current passes through the airframe and why aircraft still avoid thunderstorms.
The short answer
Conductive outer shell directs current mainly on the surface of the aircraft: the discharge enters at one point and exits at another. Systems, wiring and fuel tanks are designed with protection against electromagnetic influence and sparking.
How the plane is protected from lightning and how dangerous is the storm
After the alleged hit, the aircraft is inspected according to the established procedures. Sometimes there are small traces at the points of entry and exit of the discharge, requiring inspection or repair.
It’s not just because of the lightning. Inside the powerful cloud can be hail, strong vertical flows, icing and intense turbulence, so the crew uses a weather radar and a safe distance.