What System Safety Engineering Can Learn from the Columbia Accident

An accident investigation allows a view into an organization that is normally not possible. The strong system safety program established at NASA after the Apollo fire has evolved into a program in which the name remains but most of the important safety management and engineering functions have disappeared or are performed by contractors. The title remains, but the essence is gone. Many of the dysfunctionalities in the system safety program at NASA contributing to the Columbia accident can be seen in other groups and industries. This paper summarizes some of the lessons we can all learn from this tragedy. While there were many factors involved in the loss of the Columbia Space Shuttle, this paper concentrates on the role of system safety engineering and what can be learned about effective (and ineffective) safety efforts. The information contained in this paper comes from the Columbia Accident Investigation Board (CAIB) report (ref. 2), the SIAT report (chartered in 1999 to evaluate the Shuttle program after a number of close calls) (ref. 9), the authors’ personal experiences with NASA, and communications with current and former NASA system safety engineers. Introduction Viewing the Columbia accident from the perspective of system safety, this paper highlights the interdependent roles of culture, context, structure, and process in the accident. While the impact of the foam on the leading edge of the Shuttle wing was the precipitating event in the loss, the state of the NASA safety culture, system safety organizational structure, and safety engineering practices at NASA at the time made an accident almost inevitable. Understanding the political and social background, along with the context in which decisions were made, helps in explaining why bright and experienced engineers made what turned out to be poor decisions and what might be changed to prevent similar accidents in the future.