Photo: 123RF
Lightning strikes on a plane
What happens when lightning strikes a plane?
Asmiati Utari from Quora asks, “Can thunder strike a plane?”
I think the question should be rephrased by replacing the word ‘thunder’ with ‘lightning’. This is because, without lightning, there would be no thunder.
Lightning is a discharge of electricity in the cumulonimbus clouds. The expansion creates a shock wave that turns into a booming sound wave known as thunder.
Statistics have shown that an airplane is struck by lightning at least once a year.
Lightning is not dangerous to the modern planes. Even if there is a direct strike, it does not penetrate the cabin nor affect the engines.
When an airplane is struck by lightning, the electrical charges just traverse the length of the aircraft and exit through the static wicks or dischargers at the trailing edges of the flaps or the tail plane.
This theory is based on the Faraday Cage principle, something a science student would probably have learned from his previous physics class.
Faraday discovered that, if you put electricity through a metal cage, no matter how strong or high the voltage is, anything inside the cage is totally protected from the electricity.
If you sit by a window seat behind the wings of a plane, just look out for static wicks at the trailing edge of the wings. They are like painting brushes with fine hairs. This is where electrical charges exit when a lightning strikes the plane.
What if a lightning strikes on the airplane’s body?
Nothing very serious really. You may get some small burnt marks on the fuselage skin at the point of impact. The pilot would usually be aware of such a strike in flight. He would report this incident to the engineers after landing for further inspection.
The last incident when a lightning struck a plane was about 59 years ago in a Pan American Boeing 707 flight from San Juan, Puerto Rico to Baltimore, then to the Philadelphia International Airport on December 8, 1963.
As the plane approached the airport, the controller informed the pilots that a line of thunderstorm was in the vicinity. They were requested to remain in the holding pattern.
Shortly after that, the pilot transmitted a message, “MAYDAY MAYDAY MAYDAY. Clipper 214 is out of control!”
Investigators concluded that lightning strikes had induced the ignition of the fuel vapors in a fuel tank and had triggered an explosion
However newer planes like the Boeing 787 and the Airbus A350 are better designed and made with a higher proportion of composite materials. They are covered with a thin layer of copper which act as Faraday Cages.
Today, all planes are tested and certified for lightning strikes at the factories. They go through very rigorous lightning strike simulations before they are released for flights.
As such, you are safe during a lightning strike just like you would be in your car.
See an interesting video on ‘When Lightning Strikes Your Airplane’ here https://www.youtube.com/watch?v=m37z5R2rJ5E