Seaway performance assessment for marine vehicles

The close relationship between the ship design process and the new methodology involved in the assessment of marine vehicle performance in a seaway is shown. Without the seaway performance methodology and the onboard instrumentation needed to validate it, the Navy cannot make creditable decisions among alternative ship designs or competitive vehicle types for a particular mission. Each of the 58 links interconnecting the sixteen key elements that make up the design process and the seaway performance methodology is identified and those involving the seaway performance methodology are discussed. Three critical elements and four links, requiring substantially more research are also identified. Even though platform motions have a known profound impact on personnel, on the platform and on mission and platform systems, the links between motions and these elements are shown not to be a part of the seaway performance methodology. Rather the methodology employs 'prescribed' values of the seaway performance criteria (similar in concept to the highway speed limit) which place limits on the magnitude that the motions may safely assume.