An integration of present navy ships intact stability criteria in the perspective of ship performance assessment in a seaway

In the paper a possible integration of the present intact stability criteria for navy ships is proposed with the aim to include ship stability performance assessment in a seaway. In this view, IMO Second Generation Intact Stability Criteria (SGISC) are considered, as an interesting source of inspiration. In the background, the innovative approach formulated within the Naval Ship Code is described, as a possible framework where the above mentioned integration can take place. In order to get practical feasibility test, applications are carried out on three navy ship typologies, characterized by different sizes and operational profiles in order to compare the level of severity of the present intact stability navy criteria with the one implied by the first vulnerability level criteria of the SGISC. As a furthere step, then the second vulnerability level criterion for the dead ship stability failure mode is applied to the same set of ships. The criterion in fact can be a possible supplement of investigation, beside the usual beam winds combined with rolling criterion, in order to better frame ship behavior in a seaway.