Geographic patterns of pilot fatality rates in commuter and air taxi crashes.
Geographic information systems are widely used in studies of diseases. However, their value for aviation safety research has not been adequately explored. This study examined the geographic patterns of pilot fatality rates in commuter and air taxi operations. Crash data recorded by the National Transportation Safety Board under FAR Part 135 were used to create a digital map of all crash sites in the continental United States between 1983 and 1998. Fatality rates in crashes were calculated and then interpolated to create a contoured map of rates. A test of significance was performed using Monte Carlo simulations. High-, medium-, and low-rate areas were then compared for pilot characteristics, airplane characteristics, and crash circumstance. Of the 1094 commuter and air taxi crashes studied, 25% resulted in a pilot fatality. A large geographic area with a pilot fatality rate of > or = 36% extended through portions of Michigan, Indiana, and Illinois. A relatively low fatality rate (< 15%) prevailed over an area extending from Texas to northwest Georgia. Crashes in high-rate areas were significantly more likely than crashes elsewhere to have occurred at night and during instrument meteorological conditions. The geographic analysis revealed a distinctive pattern of pilot fatality rates from Part 135 crashes. Factors underlying the geographic pattern should be investigated, with particular attention to the great geographic variability of terrain and weather phenomena between the north and south regions of the United States.