US commercial air tour crashes, 2000-2011: burden, fatal risk factors, and FIA Score validation

INTRODUCTION

This study provides new public health data concerning the US commercial air tour industry. Risk factors for fatality in air tour crashes were analyzed to determine the value of the FIA Score in predicting fatal outcomes.

METHODS

Using the Federal Aviation Administration's (FAA) General Aviation and Air Taxi Survey and National Transportation Safety Board data, the incidence of commercial air tour crashes from 2000 through 2010 was calculated. Fatality risk factors for crashes occurring from 2000 through 2011 were analyzed using regression methods. The FIA Score, Li and Baker's fatality risk index, was validated using receiver operating characteristic (ROC) curves.

RESULTS

The industry-wide commercial air tour crash rate was 2.7 per 100,000 flight hours. The incidence rates of Part 91 and 135 commercial air tour crashes were 3.4 and 2.3 per 100,000 flight hours, respectively (relative risk [RR] 1.5, 95% confidence interval [CI] 1.1-2.1, P=0.015). Of the 152 air tour crashes that occurred from 2000 through 2011, 30 (20%) involved at least one fatality and, on average, 3.5 people died per fatal crash. Fatalities were associated with three major risk factors: fire (adjusted odds ratio [AOR] 5.1, 95% CI 1.5-16.7, P=0.008), instrument meteorological conditions (AOR 5.4, 95% CI 1.1-26.4, P=0.038), and off-airport location (AOR 7.2, 95% CI 1.6-33.2, P=0.011). The area under the FIA Score's ROC curve was 0.79 (95% CI 0.71-0.88).

DISCUSSION

Commercial air tour crash rates were high relative to similar commercial aviation operations. Disparities between Part 91 and 135 air tour crash rates reflect regulatory disparities that require FAA action. The FIA Score appeared to be a valid measurement of fatal risk in air tour crashes. The FIA should prioritize interventions that address the three major risk factors identified by this study.