Analysis of Air Taxi Accidents (20042018) and Associated Human Factors by Aircraft Performance Class

INTRODUCTION: Air taxis conduct nonscheduled transport and employ aircraft in various performance categories hereafter referred to as low, medium, and high performance, respectively. No study has yet addressed fixed-wing air taxi safety by performance category. Herein, we compared accident rates/occupant injury across air taxi airplane fleets grouped by performance category and identified human factors contributing to fatal accidents for airplanes in that category with the highest mishap rate.METHODS: Accidents (20042018) in the United States were identified from the National Transportation Safety Board database. General Aviation/Part 135 Activity Surveys provided annual fleet times. Fatal accident contributing factors were per the Human Factors Classification System (HFACS). Statistics utilized Poisson distributions, Chi-Square/Fisher, and Mann-Whitney tests.RESULTS: There were 269 air taxi mishaps (53 fatal) identified. Over the 15 yr, the accident rate (1.10/million flight hours-all categories) declined 50%, largely due to a reduction in medium/high performance category airplane crashes. However, little temporal change was observed for low performance airplanes (1.5/million flight hours) and injury severity trended higher. At the aircrew/physical environment levels, HFACS revealed decision (improper choices), skill-based (stick and rudder) and perceptual (night, instrument conditions) errors contributing to > 60% of fatal accidents involving low performance airplanes. At the organizational level, failing to correct problems, time pressures, and incentive systems contributed to 16% of fatal mishaps.CONCLUSION: Safety deficits remain for the low performance category air taxi fleet warranting increased pilot instrument flight training/utilization of the mandatory 3-axis autopilot in degraded visibility. Safety culture improvements to address issues of personnel/equipment/training deficiencies, failing to correct problems, and time pressures/a safety-compromising incentive system all need to be addressed.Budde D, Hinkelbein J, Boyd DD.