Enhanced Structural Design and Operation of Search and Rescue Craft

This paper is a conceptual overview of the approach adopted to enhance the structural design and operation of high-speed craft through a set of design curves. It outlines how to construct a structural limit curve as a function of speed and sea state severity. The curve contributes to defining the ‘operational envelope’ of the craft, which informs design teams and crews on the limits to speed for the safe operation in waves. The construction of a structural limit curve requires an understanding of the loads that the structure sustains in operation and how it responds. This is achieved through a combination of numerical hydrodynamic and structural simulations, towing tank tests and sea trials. The study, which is conducted on the Severn Class lifeboat of the Royal National Lifeboat Institution (RNLI), has wider applicability in the design of future lifeboats and small high-speed craft. Explicit results, not presented here, are referenced throughout the paper. Length overall LOA 17.00 m Length waterline LWL 15.50 m Beam overall BOA 5.62 m

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