Introduction: In the past decade, numerous studies have been published rega
rding the relationship of crash risk and mortality with respect to geograph
ic area. Methods: We analyzed data (United States only) regarding general a
viation and air taxi crashes from 1992-94 from the National Transportation
Safety Board. Data regarding 1993 flight hours and standard error were obta
ined from the Federal Aviation Administration (FAA) and pooled to provide a
reliable estimate of crash risk for 1992-94. Calculations were determined
for each state and FAA region. Results: During the 3-yr period, the calcula
ted United States crash rate is 8.9 crashes per 100,000 flight hours. The A
laskan and Northwest Mountain regions had the highest crash rates and fatal
crash rates. Discussion: This is the first study to report on geographical
differences in rates determined as crashes per 100,000 pilot hours. it sho
ws that even when the amount of flying is controlled for, crash rates and f
atal crash rates are highest in mountainous regions. Our results indicate t
hat aviation safety in mountainous regions deserves more attention.