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THE 2006 RINA – Lloyd’s Register Ship Safety Award

JB undertook the detailed design of this vessel

Extract from the submitted abstract for the RINA award:

Subsequent to the research and trials programme, the form and dimensions of the best-performing hull were fine-tuned, by the boat-builder’s consultant Naval Architect, to achieve the buoyancy and performance characteristics required for operational deployment. Material selection, hull lay-up and the processes for construction (described in the submission) were focussed on achieving minimum weight commensurate with appropriate standards for commercial vessel design and MCA certification, while achieving minimum impact upon the environment by choice of “least depletion” high-strength composites and minimisation of waste. Traditional boat-building skills have been readily adapted to these novel materials and techniques. The close involvement of the workforce, in developing the detailed vessel design and constructional processes, has provided further opportunity for weight-saving. The hull resistance data from the model tank tests were used to calculate the power required to achieve the “emergency speed”, for operational service of the full-sized launches, at predicted displacement. Machinery selection is constrained by fuel type availability, within the operational area, and fineness of hull to achieve lowest wash. There is no marine petrol available on the Tidal Thames and commercially-available inboard engines would not fit, with room for ready servicing, within the intended fine hull dimensions. A diesel outboard machinery configuration therefore became necessary. Within a very limited availability of suitable motors, Yanmar D36, 36hp diesel outboard engines were selected and built to special order.

 Calculations indicated that these engines should give an “emergency speed” of 18 knots, which exceeds that available from the existing launches. Throughout the design and build, the combination of:

• optimised low-wash/vessel displacement & performance in design; and

• careful attention to materials selection and processes in construction

should provide patrol vessels which significantly improve safety for “customer” and “stake-holder” river users and, through the reduced resistance - principally achieved through wash reduction - substantially reduce the vessels’ carbon footprint from operational fuel consumption and subsequent emissions.

The first Ecocats E31 patrol launch was delivered to the PLA in October 2006, with the second vessel of the class expected in early 2007. The vessels have a large operational platform, flexible to a variety of tasks, and will carry all equipment and resources required for duty, yet have a displacement less than half that of the current patrol launches. The hull form is expected to allow the normal patrol speed of 6-8 knots to be achieved with virtually no wash and emergency response to be achieved, at 18 knots, with one third the wash wave-height and substantially less wash energy (approximately one fifth of current) than that created by the current semi-displacement monohulls.

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