With so many bolts of lightning, it’s no wonder that people and structures get hit. Each year about 100 people are killed and about 245 injured in the United States by nature’s number one weather-related killer. Lighting-generated fires destroy more than 30,000 buildings at a loss of hundreds of millions of dollars every year.

Airplanes and spacecraft are subject to the tremendous electrical forces that can build up in the atmosphere. According to the FAA, commercial aircraft are struck an average of once every 3,000 flight hours, or about once a year. However, only one U.S. airliner has been confirmed as lost to lightning. Because of an airplane’s metal construction, lightning flows along and away from its fuselage. Almost all lightning strikes on aircraft cause only superficial damage, and passengers are protected from injury. With the advent of new composite materials for airframes and digital fly-by-wire control systems, newer aircraft may be more vulnerable than these statistics would suggest.

Spacecraft are more vulnerable than aircraft. On March 26, 1987, an Atlas/Centaur rocket and its satellite were lost when the unmanned NASA vehicle was struck by lightning. But it was an earlier strike, one that temporarily disabled the electrical systems on the Apollo 12 spacecraft onboard a Saturn V rocket on November 14, 1969, that prompted NASA to develop ways to protect its launch vehicles, and to create a better system to predict when and where lightning might strike.