A Combined Analysis of Quantitative and Qualitative of Latent Failures of Marine Accidents and Incidents due to Engine Failures and Consideration of Countermeasures

In this study, we focused on terminologies expressing the analysis results of the Japan Transport Safety Board and conducted a combined analysis of quantitative and qualitative of investigation reports related to marine accidents and incidents caused by engine failures. The results show that machine failures as hardware factors tended to be classified as "high probable." The results also show that latent failures and active errors tended to be classified as "probable.", active errors appeared simultaneously with latent failures such as design flaw of a machine. The results also show that most of the latent failures were poor machine maintenance, decisions made by machine designers and ship managers were rare, and insufficient training was not observed in investigation reports. In addition, the results show that "Assertive" and "Almost certain" included not only the causes of the failure in accidents, but also everyday successes. Based on the results of the combined analysis of quantitative and qualitative, the authors considered four countermeasures from an academic standpoint against latent failures that have commonality and relevance in the marine engineering department. The first is to record maintenance sheet against poor machine maintenance. The second is engineering countermeasures by machine designers. The third is to enhance resilience of organization as a countermeasure for decision-making by managers. The fourth is to increase and ensure everyday success of training and education to enhance resilience engineering.