Influence of Low Stability on Turning Safety of Ro-Ro Passenger Ship

To investigate the safety margin of the Ro-Ro passenger ship (ROPAX) with low stability during turning operations, a four-degree-of-freedom coupled mathematical model was established. The results indicate that during turning maneuvers, the maximum heel angle of the ROPAX vessel significantly exceeds the steady state values specified and calculated by the International Code on Intact Stability 2008 (2008 IS Code). It is noteworthy that this excessive transient heel angle, which exceeds the steady state assessment framework adopted in conventional IMO regulations, often receives insufficient attention in practical engineering and operational evaluations. Nevertheless, its impact on safety is critical. This study provides crucial evidence for evaluating the maneuvering safety margin of the ROPAX vessel and offers a valuable reference for refining stability criteria and operational guidelines for actual navigation.