Although the number of marine accidents has been on a downtrend in recent years, several accidents have occurred that have had a major social impact, such as the grounding of the supertanker Diamond Grace in Tokyo Bay in 1997. Moreover, groundings continue to account for a large percentage of the total number of judgments pronounced. For these reasons, in 1999 the Marine Accidents Inquiry Agency released a report, titled "Marine Accidents Caused by Grounding," that examines and analyzes such accidents. This report is an update of a previous document published in April 1981.
Summary of key points contained in "Marine Accidents Caused by Grounding"
1. Outline of marine accidents
A total of 861 accidents and 861 vessels upon which judgments were pronounced by local Marine Accidents Inquiry agencies were studied during a five-year period, from 1993 through 1997.
(1) Fishing vessels accounted for the largest number of groundings during the period at 316, or 36.7% of the total. Cargo ships were involved in 270 groundings, while pleasure crafts accounted for 73, passenger ships 54, tug boats 53, oil carriers 39 and other vessels 56.
(2) Vessels of less than 20 gross tons involved in groundings numbered 379, or 44.0% of the total, making this the largest weight group, followed by vessels of between 20 and 200 tons, which numbered 255; vessels between 200 and 500 tons, which totaled 150; and vessels of between 500 and 1,600 tons, which amounted to 44. As these numbers show, vessels of less than 200 gross tons accounted for more than 70% of the total number of vessels included in the study.
(3) Of the 861 vessels studied, 310, or 36.0% of the total - the largest group - were less than six years of age, followed by vessels of between seven and 14 years of age numbered 254; vessels of between 14 and 21 years of age, which totaled 192; and vessels of 14 years of age or older, generally considered superannuated vessels, which numbered 224, or 26.0% of the total.
(4) In terms of time of occurrence, a majority - 22.1% - of groundings during the period happened between 2400 and 0400 hours. The fewest groundings occurred between 1200 and 1600 hours.
(5) The most common location of groundings was the Seto Inland Sea, a body of water with a constantly high concentration of traffic, which accounted for 249 accidents, or 28.9% of the total. The Kyushu coast saw 192 groundings, the Nansei Islands 121 and the south coast of Honshu 111.
(6) Of the 842 vessels with a posted watch on the bridge that ran aground during the period, the majority - 720, or 85.5% of the total - had only one person on watch and 89 had two people on watch.
(7) Of the 842 vessels with a posted watch on the bridge, the majority - 681, or 80.9% - were being maneuvered by the master at the time of the accident. In 77.6% of these cases, the person maneuvering the vessel was over 40 years of age and in 43.0%, the person maneuvering the vessel had more than 30 years experience at sea.
