Warship Damage Stability Criteria Case Study

Abstract

All navies struggle to achieve a balance between safety and military capability, ensuring that activities in peace time are undertaken with an acceptable level of risk. Despite the need for intrinsic differences in construction, increasingly, the acceptable level of safety for the navies is becoming equivalent to those of merchant vessels under civil law. Navies are resorting to Classification Societies for assistance in this matter. Rules and regulations of the Classification Societies for ships are set within the framework of international law overseen by International Maritime Organization (IMO), particularly the international convention for the safety of life at sea (SOLAS). These “IMO” agreements are not always appropriate for the majority of warships, so that the military mission demand solutions in the design and operation that are not fully compatible with the philosophy of the conventions “IMO” and prescriptive solutions. Separate rules of the Classification Societies of the conventions “IMO”, to apply to ships of war, create a vacuum that can lead to confusion. This confusion can be misinterpreted and as a result there can be a drop in safety standards. Stability in case of collision is a critical theme to maintain buoyancy in ships. These aspects are even more critical given the increasing size of the boats and the growing number of passengers and crews onboard. Both experience and performed studies demonstrate that the most dangerous issue for the ships with closed deck is the impact of an accumulation of water on the deck. The studies have clearly shown that the residual freeboard of the ship and the height of the waves in a specific sea area influence in a very relevant manner the amount of water that could be accumulated after a clash. The article concludes by presenting a series of comparisons between the criteria used by both, leading to some interesting conclusions as to the current criteria used by the navy. This can be enormously improved with a few minor changes, to maintain the integrity of its basic approach, and increase the similarities with the criterion of “IMO”, such as the calculation of water on deck out in the Stockholm Agreement.