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www.sname.org/sname/mt April 2013 result in construction of large-scale prototypes at a cost of the same magnitude, or cheaper than other alternatives. Of course, there are disadvantag es to constructing large-scale prototypes. Some of the disadvantages include requiring design work to support production at an earlier project stage than would otherwise be envisioned, and testing limited to the hull form variation chosen for construction (multiple prototypes may be too costly). Other disadvan- tages include test results being limited in applicability to the full-scale conditions present during testing, and poten- tial crew safety risks during testing of truly novel concepts in extreme conditions. Clearly, there are many facets of small craft perfor- mance?from the relatively simple calm water resistance prediction to the much more complicated dynamic response in a seaway?that are beyond the capability of current, straightforward analysis techniques. ere are approaches that can be taken to provide guidance as new concepts are developed, but much more research is needed regarding the hydrodynamics of high-per- formance small craft. In particular, there is a need for experimental data for a wide variety of hull forms oper- ating in the planing regime (volumetric Froude numbers above 3) in calm water and in waves. is data is needed to support assessment of a variety of numerical calcula- tion methods so they can be used appropriately and with con dence in engineering applications. Most importantly, experimental data and hull form geometries that are publicly releasable are necessary so they can be used by members of the small craft community who are involved in development of numerical prediction techniques. Another important facet of future research for small, high-performance craft, particularly in a time when funding for such research is extremely limited, is close col- laboration of the entire spectrum of personnel involved with small craft development. It is critical that personnel developing numerical techniques, performing experiments, analyzing experimental data, and designing/engineering/ developing small, high-performance craft communicate so that as opportunities arise for testing, at model or full scale, consideration can be given to using those opportu- nities to collect data to support development of analysis techniques for these craft. For example, it is important for code developers to unders tand the charact eristics that designers/engineers need to evaluate so that simulations of those characteristics, or equations for predicting them, can be developed.Similarly, experimenters need that information, as well as a detailed understanding of how that information should be collected, so that it can be used to facilitate evaluation of new analysis techniques. Whether a persons interest is in theoretical research, experimentation/analysis, or in design/engineering as it relates to small, high-performance craft, there is enormous opportunity to explore the eld of hydrodynamics and provide signi cant contributions that enhance the state of the art for predicting the performance of these craft. MTChristine Schleicher is a naval architect at the NSWCCD Combatant Craft Division, and supports various aspects of research, design and engi- neering for a variety of naval small craft. THE ADVANTAGE OF large- scale (or even full-scale) prototyping is that many of the errors introduced in numerical calculations or model scale testing are eliminated. LOMOceans Azzum , a 12 m trimaran, has a v-bottom hull shape and relies on dynamic lift to reduce wetted area.