Ship Stability Calculation for Cause Analysis of No. 501 Oryong Sinking Accident

제501 오룡호 침몰사고 원인분석을 위한 선박 복원성 계산

Abstract

Deep-sea fishing vessel No. 501 Oryong was fully flooded through its openings and sank to the bottom of the Bering Sea. The tragic accident was attributed to rough sea weather after a fishing operation in the Bering Sea, and led to the death or loss of many crewmen. In this study, the ship stability calculation was carried out using KST-SHIP (ship calculation system of KST), considering the free surface effect and fish catch arrangement according to the progress of its sinking accident, and stability after flooding was analyzed. The calculation results obtained using KST-SHIP were verified by comparing them to intact stability calculation sheet of the accident ship under the full load departure condition, and intact stability according to displacement from the departure of accident ship up to the moment of the accident was calculated and analyzed. The stability after flooding was also calculated and analyzed according to the progress during its sinking accident.

원양어선 제501 오룡호는 황천 중인 베링해에서 조업 후 피항하던 중 개구부를 통한 침수로 인하여 침몰하였으며 많은 선원들이 사망하고 실종되었다. 본 연구에서는 사고선박 침몰사고의 진행상황 별 유동수 영향과 어획물 배치 등을 고려한 선박복원성 계산을 KST-SHIP (선박안전기술공단 선박계산시스템)을 사용하여 수행하고 사고선박의 침몰사고 시의 침수 후 선박복원성을 분석하였다. 먼저 만재출항상태 (Full Load Departure Condition)에서의 사고선박의 비손상 복원성 계산서와 KST-SHIP을 사용한 비손상 선박복원성 계산 결과를 비교하여 검증하고, 사고선박의 출항 시부터 사고 직전까지의 배수량에 따른 비손상 복원성 계산을 수행하여 비손상 복원성을 분석하였다. 또한 사고선박 침몰사고 시의 진행상황 별 침수 후 선박복원성 계산을 수행하여 침수 후 복원성도 분석하였다.

Fig. 1 Scenery of deep-sea fishing vessel No. 501 Oryong

Fig. 2 Sinking location in the Bering Sea

Fig. 3 Weight distribution under full load departure condition

Fig. 5 Comparison of righting arm (GZ) curve according to displacement from 7. 10. ∼ 12. 1.

Fig. 6 Comparison of righting arm (GZ) curve according to seawater inflow opening in morning and right before accident on 12. 1

Fig. 7 Laden situation of fish catch according to sinking accident progress

Fig. 8 Flooding compartment situation in Case 1

Fig. 9 Righting arm (GZ) curve in Case 1

Fig. 10 Flooding compartment situation in Case 2

Fig. 11 Righting arm (GZ) curve in Case 2

Fig. 4 Righting arm (GZ) curve under full load departure condition

Table 1 Comparison of hydrostatic characteristics of stability calculation sheet and KST-SHIP calculation

Table 2 Comparison of each compartment volume of stability calculation sheet and KST-SHIP calculation

Table 3 Hydrostatic characteristics according to weight under full load departure condition

Table 4 Hydrostatic characteristics of total ship under full load departure condition

Table 6 Comparison of stability criteria between stability calculation sheet & KST-SHIP calculation under full load departure condition

Table 5 Righting arm (GZ) according to heeling angle under full load departure condition

Table 7 Displacement and draft according to loading condition at each fishing date on voyage

Table 8 Intact stability criteria on July 10, August 14, in the morning and right before accident on December 1

Table 9 Comparison of stability criteria according to displacement from 7. 10. ∼ 12. 1.

Table 10 Comparison of stability criteria according to seawater inflow opening in morning & right before accident on 12. 1

Table 11 Permeability according to flooding compartment in Case 1

Table 12 Righting arm (GZ) and area ratio in Case 1

Table 13 Stability criteria after flooding in Case 1

Table 14 Permeability according to flooding compartment in Case 2

Table 15 Righting arm (GZ) and area ratio in Case 2

Table 16 Stability criteria after flooding in Case 2