An Evaluation of Stability Parameter of Small Purse Seiner

Abstract

Purse Seiner is a kind of fishing boat which is operated to catch small pelagic fishes with circle net at night time. This boat is constructed by local boat builders without considering any design parameters which impacts on limitation in boat’s operation particularly stability parameters. In order to evaluate stability parameter inclining test was executed to obtain basic stability parameters of metacentre height GM and vertical centre of gravity KG. A case study was conducted with an observed boat of “Purse Seiner Yana” at Hitu Village in Ambon Island. The study began with providing related documents and executing inclining test. The value KG of 0.874 meter and nondimensional ratio KG/H of 0.740 were found at empty ship (departure) condition, where H is deck height. These values were used further to evaluate stability parameter at large angles of inclination at any loading conditions (arrival). A scenario of variation of placement cargo (fishes) on deck and at fish hold was executed. Placement of cargo on deck decreased stability value followed by combination of placement cargo on deck and fish hold. In fact, all load variations were result in the boat is still stable particularly cargo 3 tons on deck and 3 tons in fish hold. The results of cargo variation are presented in value of KG and ratio of KG/H according to loading positions and quantities. In addition, regression equations are provided to assist designers or boat operators to find any values of loading conditions, particularly at early design phase. The results may be applied as justification for the application of Mobile Phone to evaluate boat’s stability during operation.