![]() These transients are called lightning indirect effects. Lightning traveling on the exterior skin of an aircraft has the potential to induce transients into wires or equipment beneath the skin. So, in addition to safeguarding the aircraft's exterior, the lightning protection engineer must make sure that no damaging surges or transients can reach the sensitive equipment inside the aircraft. These computers, like all computers, are sometimes susceptible to upset from power surges. Modern passenger jets have miles of wires and dozens of computers and other instruments that control everything from the engines to the passengers' headsets. In this case, the composites contain an embedded layer of conductive fibers or screens designed to carry lightning currents. ![]() Some modern aircraft are made of advanced composite materials, which by themselves are significantly less conductive than aluminum. By making sure that no gaps exist in this conductive path, the engineer can assure that most of the lightning current will remain on the exterior of the aircraft. ![]() Most aircraft skins consist primarily of aluminum, which conducts electricity very well. Pilots occasionally report temporary flickering of lights or short-lived interference with instruments. The current will travel through the conductive exterior skin and structures of the aircraft and exit off some other extremity, such as the tail. The airplane then flies through the lightning flash, which reattaches itself to the fuselage at other locations while the airplane is in the electric "circuit" between the cloud regions of opposite polarity. Initially, the lightning will attach to an extremity such as the nose or wing tip. Today, airplanes receive a rigorous set of lightning certification tests to verify the safety of their designs.Īlthough passengers and crew may see a flash and hear a loud noise if lightning strikes their plane, nothing serious should happen because of the careful lightning protection engineered into the aircraft and its sensitive components. As a result, protection techniques have improved. Since then, much has been learned about how lightning can affect airplanes. directly attributed to lightning occurred in 1967, when lightning caused a catastrophic fuel tank explosion. The last confirmed commercial plane crash in the U.S. Although record keeping is poor, smaller business and private airplanes are thought to be struck less frequently because of their small size and because they often can avoid weather that is conducive to lightning strikes. In these instances, the lightning flash originates at the airplane and extends away in opposite directions. In fact, aircraft often trigger lightning when flying through a heavily charged region of a cloud. commercial fleet is struck lightly by lightning more than once each year. It is estimated that on average, each airplane in the U.S. Rupke, senior engineer at Lightning Technologies, Inc., (LTI) in Pittsfield, Mass., provides the following explanation:
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