The first patent on an inflatable crash-landing device for airplanes was filed during World War II. In 1973, the first commercial airbags appeared in a run of 1,000 Chevrolet Impalas. Since model year 1998, all new cars sold in the United States have been required to have airbags on both driver and passenger sides. To date, statistics show that airbags reduce the risk of dying in a direct frontal crash by about 30 percent. Today, some cars have six or even eight airbags.