Airplanes are primarily protected from lightning strikes through a combination of design and electrical principles, primarily by directing the electrical current safely around the aircraft.
How Aircraft Manage Lightning Strikes
Here's a breakdown of how airplanes manage lightning strikes:
1. Conductivity of the Airframe
- The aircraft's exterior is made mostly of aluminum, which is a highly conductive material. This allows the electricity from a lightning strike to travel along the skin of the plane instead of through the interior, which is where passengers and vital systems are located.
2. Discharge Points
- Small metal protrusions on the wing and rear edge of the tail are used to discharge the static charge accumulated on the aircraft. These static discharge wicks, sometimes referred to as static dischargers, help prevent the buildup of static electricity and also aid in safely dissipating the powerful current from a lightning strike.
- When the plane lands, the electricity accumulated during the flight is discharged through grounding systems.
3. Faraday Cage Effect
- The metallic exterior of the aircraft acts like a Faraday cage. This means that the electrical current from a lightning strike is conducted around the outer shell of the plane and doesn't penetrate inside to the cabin. This principle protects both passengers and vital onboard electronics.
4. Internal Shielding
- Sensitive electronic equipment inside the aircraft is protected by internal shielding. This minimizes the risk of interference or damage from the lightning strike.
5. Bonding
- All metallic components of the aircraft are electrically bonded together to ensure that there are no pathways of high resistance where dangerous arcing and sparks can occur. This facilitates the smooth flow of electrical current along the plane’s surface.
6. Safety Procedures
- Airlines and pilots are trained in procedures for handling severe weather including lightning storms. The planes themselves are regularly inspected to ensure that the protections systems are working properly.
In summary, airplane protection against lightning is comprehensive:
- The aircraft’s design ensures electricity passes safely across its exterior.
- Specific components discharge the static electricity buildup.
- Interior shielding protects both passengers and equipment.
The plane acts as a conductive pathway for the powerful electrical current, ensuring it does not harm anyone inside. Despite the visual spectacle of a lightning strike, the plane is designed to continue flying safely and uninterrupted.
