Lightning strikes can be damaging to buildings and equipment, as well as dangerous to people. To protect against that, the circuits employ surge protectors to either block or short circuit excess current. Protecting sensitive equipmentĪlthough the electrical charges are connected through the metal skin of the airplane, there still is the possibility that some current can leak into the electrical system and cause damage to sensitive electrical and computer equipment. These static wicks actually encourage the static buildup on the airframe, during normal flying conditions, to bleed off so that the charges will not accumulate and cause radio interference. Since they look like little lightning rods, many people think they are used to attract lightning to them, as a way to protect the aircraft. Misconception on static wicksĪ common misconception is that the static wicks on the edges of the wings. The skin around the tanks, fasteners and fuel filler caps must be able to prevent sparks near the fuel. Likewise, the fuel system must be protected from even tiny sparks caused the lightning currents in the aircraft exterior that could result in an explosion. (See Electrostatic Induction for more information.) Preventing fuel explosions The problems caused by these lightning effects can be averted. By shielding wiring and equipment and adding proper grounding and surge suppression devices. However, when the lightning is traveling along the exterior of the aircraft, transient effects, similar to electrostatic induction, can create power surges in the aircraft wiring that could damage electronics and aircraft computers. Since the aircraft is speeding through the clouds, the excess charges will then be dissipated into a region of cloud that has an opposite charge. The aircraft are designed to make sure that there are no gaps in this conductive path. Since most commercial aircraft skins are primarily made of aluminum, a very good conductor of electricity, most of the lightning current remains on the exterior skin of the aircraft. This system works so effectively that the last crash due to lightning was over 40 years ago. The way commercial aircraft are protected from lightning damage is by keeping the lighting current in the outer skin of the airplane. In fact, individual airliners are struck by lightning an average of once a year. In such a situation, it would seem that the airplane could be in danger of being struck by lightning and damaged. Protecting an airplane in a stormĪlthough most commercial airliners try to avoid flying through a thunderstorm they occasionally have no choice. In most residential buildings, there is not lightning arrester, so surge protectors are important. Surge protectors are often used between the power and communications outlets and the computer or other electronic device. Usually, lightning arresters are placed where the power and communication lines enter the building. They create a means to short circuit the surge in power, limiting the rise in voltage. Lightning arrester is at input to buildingĪ lightning arrester is a device that is connected between each electrical conductor in a power and a communications system and the Earth or ground. When lightning strikes an electrical power line or communication line external to a building or when it strikes a building and jumps to one of those lines, it can create a surge of current that will burn out or damage electronic instrument and computers. It wasn't until 2000 that scientists at the Langmuir Laboratory for Atmospheric Research in New Mexico proved that a rod with a rounded or spherical end works better. When Franklin invented the lightning rod, he felt that a sharp tip would be best for attracting electrical charges and thus lightning. But also, the configuration of tip of the lightning rod is such that it is a good receptor for lightning. The idea is that the electricity will take the path of least resistance and thus bypass the structure of the building as it travels to the ground. Often buildings prone to being struck by lightning will have a network of lightning rods and conductors. Included in the system is the metal cable or rod that extends down into the ground and electrodes in the earth to safely dissipate the energy away. Lighting diversion systemĪ lightning rod (also called lightning conductor) is just part of a lighting diversion system meant to protect building from damage due to a lightning strike. In 1752, Benjamin Franklin invented the lightning rod, which was meant to extend above a building and attract the lightning bolt to the rod, where it could be diverted harmlessly to the ground. A high tree in a field or a tall building can be likely lightning targets. When lightning jumps toward the earth from a cloud during a thunderstorm, it will seek out the highest structure that has collected electrical charges opposite of the static electric charges in the cloud.
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