How is the lightning repelled from the airplane wings?

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My answer to How is the lightning repelled from the airplane wings?

Answer by Thomas Zerbarini:

Lightning is actually

not “repelled” from aircraft or their wings.

Aircraft are designed to shed static electricity build up; and, they are also designed to withstand a lightning strike.

Most commercial aircraft basic protection is its thick metal structure that can allow all or most of the lightning current to travel, like a faraday cage, around the outsise of the metal structure. Lightning typically attaches to an aircraft structure from the nose area or upper center fuselage area and exists in multiple points on the bottom and rear of the aicraft. See the image below:

The most common damage that can occur from a lightning strike includes electromagnetic component disruption or failure:

popped rivets:

and composite/fiberglass damage:

Damage can range from light to severe depending on the aircraft type and strength of the lightning. Boeing has a great article on lightning Protection, Inspection, and Repair.

Here is a great Smithsonian Channel video “When Lightning Strikes your Airplane.” It primarily talks about how they protect aircraft that use more composite materials instead of metal on aircraft:

https://www.youtube.com/watch?v=m37z5R2rJ5E

Static Build up:

As an aircraft flies through the air, the friction of the air rubbing past the aircraft creates a static electricity build up. If you have dry particles like dust, ash and ice crystals you increase the potential of static electricity building up on the aircraft. Much like rubbing a balloon against your wool shirt or dragging your feet across the rug.

Aircraft utilize static wicks or Static discharges to dissipate the static charge before it can build up on the aircraft.

Static build up can be a nusiance to pilots and their communications and sometimes navigation instruments. They can interfere and cause reduced reception and less clear transmissions.

One of the coolest things a large static build up can produce on an aircraft is Saint Elmos Fire. This is the discharging of the static build up in small or large flashes. Here is a small discharge along the conductive material in the aircrafts windshield.

These discharges are harmless and somewhat entertaining.

Thomas Zerbarini

How is the lightning repelled from the airplane wings?

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