2016년 3월 6.67톤 어선이 크레인 작업을 하던 중 복원성 상실로 인한 전복 사고가 발생하였다. 전복은 충돌, 접촉, 좌초, 화재 및 폭발의 결과로 발생한 사고는 제외하고 선박이 뒤집힌 것을 말한다. 지난 9년동안(2010-2018), 전복 사고는 전체 해양사고의 2.34%를 차 지하고 있으며 증가와 감소를 반복하고 있다. 10톤 미만 소형어선의 주된 전복사고 원인은 부적절한 선적에 따른 복원성 상실이다. 어선 법에 따르면 소형 어선은 복원성과 1톤 미만 제한 하중 크레인에 대해서 복원성과 예비검사를 면제해 주고 있다. 본 연구는 고성에서 발 생한 소형 어선의 전복 사고 재결서의 원인으로 언급된 사항 중 크레인 증량에 따른 복원 모멘트 감소에 대해 실제 제원이 비슷한 어선 을 모델링하여 이를 통해 사고 전·후의 어선 상태를 가상하여 복원성을 비교하였다. 그 결과 기존 보다 무거운 크레인으로의 교체 시에는 복원 모멘트 감소와 현단몰입각의 감소로 전복의 위험성이 증가되었다. 표준재화 상태에서는 입·출항시 보다는 어로 활동을 하고 있는 상황에서의 복원 모멘트가 감소되는 것을 확인하였다.

A tragic disaster happened by capsizing O–Ryong 501 trawler at Western Bering Sea in 1st, Dec. 2014. The disaster was caused by the severe weather and the long deferred escape from the storm in fully developed high sea. Lots of sea water from poop deck rushed into the fish ponder with fishes all together after hauling net and then remove the fishes from codend. The vessel became to incline to the one side caused by the weight and the free surface effect of flood sea waters and fishes at initial stage. In spite of crews all effort to discharge the waters, but the work was not achieved successfully. For the worse thing, the order of abandon ship was issued too late. After all, the ship capsized and sank, then almost crews became to the victims of the casualty including captain. In this paper, author carried out restrictively the calculation of dynamic factors influenced on the disaster including the weather condition and effects of the flood sea waters, and found out that the most important causes of the disaster were the decrease of stabilities, GM was decreased from 0.9m to 0.08 m, and the high waves which led to the vessel disaster.

A historical tragic disaster happened by capsizing the passenger ship Sewol at South Western Sea of Korea in 16, April 2014. The ship which left Incheon harbour to bound for Jeju port passed Maengol strait and reached to approach of Byung Pung island, and then capsized and sank with a sudden inclination to the portside in the mean time of starboard the helm. In this time, the ship which has very poor stability without sufficient ballast waters and with over loading cargo listed port side caused by the centrifugal force acting to the outside of turning. A lot of cargoes not fastened moved to the port side consequently, and the ship came to beam end to capsize and sank in the end. No crews including especially captain would offer their own duties in a such extremely urgent time, as a result, enormous number of victims broke out including a lot of student. In this report, author carried out some calculation on the factors which influenced on the stability of the ship, i.e. the ship's speed, the rudder angle, the weight of cargoes and distance of movement, the surface effect of liquid in the tank. We found out that the most causes of capsize were the poor stability with heavy cargoes and insufficient amount of ballast water against the rule, and the cargoes unfastened moved one side to add the inclination as well. Above all, the owner be blamable because of the illegally operating the ship without keeping the rule.