FIA Score: a simple risk index for predicting fatality in aviation crashes

Previous studies have identified a variety of risk factors for occupant fatality in aviation crashes. A simple composite index measuring the risk of fatality in a given crash, however, is lacking.

The FIA Score is a four-point (0-3) index based on the number of three risk factors for occupant fatality present in a given aviation crash: fire, instrument meteorological condition, and being away from airport. We assessed the validity of this risk index using aviation crash investigation data from the National Transportation Safety Board for the years 1983 to 2005. Sensitivity, specificity, and area under the receiver operating characteristic curve according to the type of flight operations were computed. The analysis was first limited to pilot-in-command fatality and then replicated to any fatality.

The study sample consisted of 44,828 aviation crashes, in which 7,889 (18%) pilots-in-command were fatally injured. The pilot crash fatality rate was 3%, 18%, 62%, and 89% for FIA Scores of 0 (none of the 3 risk factors present), 1, 2, and 3 (all 3 risk factors present), respectively. The FIA Score performed consistently well in predicting pilot fatality in crashes involving different types of flight operations. The area under receiver operating characteristic curve was 0.86 (95% confidence interval [CI]: 0.78-0.95) for major airline crashes, 0.83 (95% CI: 0.80-0.85) for commuter and air taxi crashes, and 0.81 (95% CI: 0.81-0.82) for general aviation crashes. The results were similar when the outcome was measured by whether or not the crash resulted in any fatality.

The FIA Score appears to be a valid tool for measuring fatality risk in aviation crashes. Given its simplicity, the FIA risk index should be readily applicable to trauma research and prevention.