Earlier this year we had reason to take a fresh look at the VPP-based ORCi rule, which continues to be popular in the eastern Mediterranean and Baltic, and subsequently carried out an in-depth analysis of the rule’s strengths, weakness and opportunities, using Numeca’s highly accurate FINE-Marine RANS CFD code on our own computer cluster to probe for errors and opportunities within the algorithms.

An effective process we use for designing to any rule is to first identify the unrated aspects and maximise or minimise accordingly, then using a combination of judgement, experience and analysis we maximise the underrated attributes and minimise the overrated effects, all while meeting the client’s brief in terms of size, budget, competition and ease of use.

Designing to ORCi requires a totally different approach to IRC. IRC has a similar number of measurements to a typical box rule, so after setting our own box limits according to studies of the design space, we proceed as if it were a box rule design and we simply maximise performance within the limits of the box...

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Apart from floating on the same sea and being blown by the same winds, people who race across the ocean and those who cruise it seem to live in two parallel worlds. Once discovered, the speed thing is difficult to put down, and most ocean-racing buffs would turn a bit grumpy on a long voyage at 6kt or so. Although this cultural divide is explicable, the paucity of exchange of ideas between these two separate worlds is an unnatural constraint on the development of true, ocean-cruising yachts that are, nonetheless, a real pleasure to sail.

Your average committed speedster might ask why you wouldn’t just put some plastic boxes of food on a raceboat and take it cruising. People do that, but usually as part of a delivery to or from some regatta venue. But here we’re talking more about live-aboard, long-range cruising – for which something with more heft is required.

For an enhanced ocean-cruising yacht a crucial and fundamental decision first has to me made about how the dspl/length ratio is to be pitched and, at the risk of being banned from these pages for ever more, I’d say that some mass in these boats is pretty much what is needed...

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Below: The 57-foot Irens-designed schooner Farfarer displaces some 28 tonnes – no lightweight but certainly not as heavy as some other world-cruisers of this size. Farfarer’s predecessor Maggie B finished a circumnavigation shortly before being destroyed in a boatyard fire on her return