An Analysis of Commercial Aircraft Accidents Using the Human Factors Analysis and Classification System (HFACS): The Case of The United States

Abstract

A significant portion of aviation accidents is attributed to human factors, highlighting the need for comprehensive and systematic analyses in this field. This study examines 57 scheduled commercial aircraft accidents that occurred in the United States between 2020 and 2024 using the Human Factors Analysis and Classification System (HFACS) framework, with the aim of evaluating the contributing human factors in a multi-layered manner. The research demonstrates that human errors are not solely the result of individual performance deficiencies but also stem from systemic, managerial, and organizational shortcomings. The study utilizes official accident reports from the United States National Transportation Safety Board (NTSB), analysed through content and descriptive analysis techniques. Only accidents involving turbofan-powered fixed-wing aircraft engaged in scheduled passenger transportation were included. NTSB reports are considered highly reliable primary sources due to their comprehensive analysis of technical, operational, and human factors related to aviation incidents. Based on 207 coding conducted according to the HFACS model, human errors were analysed across four levels: unsafe acts, preconditions for unsafe acts, supervisory factors, and organizational influences. The analysis revealed that the most frequently observed human errors were related to decision-making and perception, primarily resulting from cognitive limitations, information deficiencies, and inadequate situational awareness. Environmental factors such as turbulence and technological shortcomings were also identified as direct threats to operational safety. Furthermore, operational planning errors, the neglect of safety priorities, dysfunctional procedures, and insufficient resource management were highlighted as indirect contributors stemming from managerial and organizational deficiencies. The findings emphasize the necessity of developing accident prevention strategies not only at the individual level but also across organizational and systemic levels.