A Quantitative Analysis of Uncertainty in Vessel Groundings

Rarely does marine salvage occur in conditions conducive to obtaining the necessary draft readings to accurately estimate a ground reaction. Obtaining accurate information on the condition of grounded vessels is difficult under the best environmental conditions. The analysis presented here quantifies the uncertainty associated with ground reaction calculations using the propagation of errors methodology. Basic relationships gleaned from classic naval architecture calculations are analyzed to examine the importance of each input and develop a cost/benefit relationship for optimizing each parameter. This study provides a framework for evaluating uncertainty in future salvage cases. Included in this analysis is evaluation of multiple real-world casualty responses from planning to execution. Quantifying the accuracy of information available and the extent to which this information is known provides stakeholders with the ability to create a more well-informed picture of the inherent risks of a given salvage operation. Using the framework described here, actionable recommendations are developed which may be used in the development of plans for responding to future grounding scenarios. In particular, this analysis supports the need for flexibility in salvage plans and emphasizes the value in empowering on-scene leaders to make adjustments in response to new information as it becomes available.