Modification of the Intact Stability Criteria to Assess the Ship Survivability from Capsizing

Assessment of ship survivability is a main requirement that must be satisfied before the ship isoperated. Some assessments of ship survivability which has been applied by IMO such as Intact Stability and Damage Stability in calm water needs to be developed. Sometimes ships are operated in rough water with irregular waves, so the future criteria of ship stability should be associated with ship motion and capsizinginthewaves. Ship capsizing isalways correlated with non-linier ship motion. This paper discusses how to modify intact stability criteria to be righting lever arm onthecalm waterwhich can be used to assess ship survivability from capsizing in the waves using safe basin erosion method. The results shows that the modified IMO‘s Intact Stability Criteria can be considered as assesment of survival of ship capsizing. And the bilge keels have significat effect for improving the survivability of ship capsizing.