Thoughts on integrating stability into risk based methods for naval ship design

Abstract

Design for Safety (DFS), Goal Based Standards (GBS) and Formal Safety Assessment (FSA) are powerful tools which establish a framework for integrating stability into a risk based design process. They provide a foundation for the development of novel designs which can provide insight that is not attainable through any other means. Naval ships are complex systems, sometimes operating in an environment defined by risk acceptance and risk taking beyond those of their commercial counterparts. The hazards seen by a naval ship in its service life may not be foreseen during design. The development of a design for safety process for naval ships should be capable of reflecting the nature of the military mission. Concurrently, there is certain fidelity inherent in the process that should be carefully defined. Three cases to categorize the risk assessment ‘fidelity’ are defined and discussed. These highlight the dangers of overstating and understating risk. Lastly the challenges of defining intact and damage stability risk in light of the sensitivity to the state of knowledge for naval ships are discussed.