• Journal of Fisheries and Marine Sciences Education
• /
• v.21 no.1
• /
• pp.68-77
• /
• 2009

In this study it will be discussed how to solve the problem of discomfort from rolling motion on the small fishing boats. Up to now, the equipments of reducing rolling system can be examined by various case, but difficult to apply small vessel by function, space and costly establishment. A way of improving the feeling of getting on a boat through the equipped sail at stern edge of bulwark top was researched and developed. The author has tested the sailing performance of the experimental skiff boat, from the signals obtained by the inclinometer in irregular waves and compared with the results got in sail on and off mode operation for 10 minutes duration at the conditions of stop and underway. These data has been analyzed in the application statistical methods. Eventually we summarize the analyzed results obtained from the vessel while stationary and underway for two cases, the vessel with a sail and the vessel without a sail. The field test was done in Jeju outer harbor. The ratio of the motion responses at resonance for the sail with and without cases indicate that under given conditions the motion was reduced by the efficiency of diminution is 4.726%, 2.792% in the stopping and 11.663%, 3.282% in the underway and mean rolling periods are 2.158, 2.142, 2.421, 2.412sec. and 1.968, 1.963, 2.089, 2.051sec. respectively. Consequently the efficiency of diminution was higher when the ship is underway and rolling periods got longer in the equipped sail.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.28 no.6
• /
• pp.955-964
• /
• 2022

According to the statistics of maritime accidents statistics that have occurred in Korea over the past five years, maritime accidents caused by fishing boats have increased every year from 1,646 in 2016 to 2,100 in 2020. In particular, of the 378 capsizing accidents that have occurred in the past five years, 252 capsizing accidents of fishing boats account for a high proportion of 66.7%, therefore, it is urgent to come up with countermeasures. In this study, to determine the cause of the capsizing accident of fishing boat No. 66 poongsung, data such as stability and seawater inflow routes were collected, and the effects of waterproof, additional wood decks, and windbreakers on stability on were quantitatively analyzed. Additional decks, windbreakers, and waterproof installed in No. 66 poongsung cause initial list, deteriorate stability, and fail to meet fishing boat structural standards. In addition, it was analyzed that the stability was weakened due to the characteristics of the hull shape of No. 66 poongsung. To estimate the stability at the time of the accident, the stability at the time of the working in the fishing ground condition, amount of seawater inflow according to the change in sea conditions, hull oscillation situation, and change in stability due to the hull factor were calculated. As a result, the minimum GoM was satisfied at the time of working in the fishing ground, but it could not be restored at the maximum wave height of 4 m, and the minimum GoM was not satisfied at the maximum wave height of 4 m owing to the influence of seawater inflow and oscillation due to the hull list. However, the minimum GoM was satisfied if additional decks and windbreakers installation was excluded among the factors affecting the stability of No. 66 poongsung.