AIRCRAFT ACCIDENTS

Human Error Causing Aircraft Accidents



Human Error Causing Aircraft Accidents

Introduction

Human Error

Investigations conducted by the National Aeronautics and Space Administration into the causes of airline accidents showed that more than 70 percent involved some degree of human error (Muthard & Wickens, 2003) . Safety analysts have attempted to identify the sources of these errors using a number of theoretical and empirical tools. The tools used to analyze human error can broadly be defined as investigation, classification, estimation of probability and severity and assessment of correctability. The earliest attempts at identifying and mitigating human error began with the first attempts to investigate the causes of early aircraft accidents and incidents. The methodology predominate in these early investigative efforts was the fly-fix-fly technique, but as aircraft became more sophisticated, classification of human error grew more popular (Holcomb & Faaborg, 2005). Classification of the errors uncovered during an accident or incident investigation can provide information that aid in the development of error mitigation strategies. Determining the probability of an error or its severity can also mitigate human error. The extremely competitive nature of the commercial aviation industry dictates a world of finite resources that are ultimately determined by the law of diminishing return on investment; which necessitate the estimation of the probability and severity of human error. Consequently, the reduction of human errors that are very likely to occur and will have grave consequences if they do, should be allocated much greater resources then errors that are unlikely to occur and will have little consequence if they do. Although probability and severity of error are as equally important in the overall analysis of human error as investigation and classification, the probability and severity of error are outside the scope of this paper, (Wiegmann & Shappell, 2003)). Finally, after the categories of errors are established, correct ability of the errors are the next and ultimate concern in mitigating pilot errors; as developing an actionable plan to aid in the flight training development program is the overall goal of a classification system.

Wells and Rodrigues (2003) noted that in the early days of aviation, mechanical failure accounted for 80% of aircraft accidents while the remaining 20% were the result of human error; however, by the 1980s human error accounted for 80% of accidents. The reversal was a result of improving technology and enhanced aircraft reliability; thus, shifting the focus of aviation safety officials to human error. Mechanics were seldom considered because pilot error quickly became the accepted cause of most accidents (Wiegmann & Shappell, 2001b). Aviation regulatory agency officials thus focused enforcement efforts exclusively on the pilot workforce in the U.S. and U.K. (Wiegmann & Shappell, 2001a). Unfortunately, by the 1990s, several high-profile lapses in mechanic judgment drew attention to the regulation of human factors in the mechanic workforce.

In 1988, an Aloha Airlines Boeing 737 suffered a spectacular structural failure when the fuselage structure surrounding the passenger compartment came off the aircraft in flight. Mechanics had repeatedly failed to detect progressive cracking of the ...