To investigate the cause of the distress, in the present marine accident inquies, charts of the vessels concerned and the course recorder data are submitted as physical evidence. Master's witness is also submitted as complementary evidence. However, this process could be less precise and objective in identifying the cause of the distress. For traffic control, radar images are recorded by MARTIS (MARINE TRAFFIC INFORMATION SERVICE). In this study, we reexamine the process to investigate the cause of collision by using the record of the radar images.
