Analysis of deck house height and center of gravity in anti-capsize patrol boat

The design of patrol boats, especially in Indonesian waters which have extreme sea conditions, requires fairly good stability capabilities and special self-righting capabilities. Designing a self-righting ship will be closely related to the ship stability because the center of gravity (G) is affected by the load and the height of the deckhouse of a ship, which has implications for the ship's self-righting. Present study was carried out with experimental study for patrol boat design that has capability self-righting moment. The patroal boat has 4 deckhouse height variations with 2.01 m, 2.11 m, 2.21 m, and 2.31 m, respectively. There are 4 variations of the load conditions, i.e., the condition with 50% of the maximum amount of cargo, the condition 50% the passengers and cargo, full load condition without passengers, and the last one is the condition of the passenger baggage is only 50%. The results showed that a deckhouse with a height of 2.01 m has the worst GZ curve analysis, where in some conditions the results touch a negative number before heeling to 180°. The results showed by trial and error that the minimum deckhouse height is 2.07 m to have a self-righting moment in all conditions.