IRC
Are you looking in the right place?
We are inching towards the conclusion of an extraordinary season with events cancelled and the international offshore circuit depleted beyond recognition. Social distancing makes multiple crews and overnight voyages difficult, if not impossible, with no immediate end to this requirement in sight at this time. This will not be news to you and in fact you are probably fed up of reading the same head- lines, so I propose we look forward and consider the racing next year with a focus on the smaller boats that are currently doing particularly well in a shorthanded crew configuration. The Rolex Fastnet Race has in recent years seen the smaller
French-sailed, French-designed IRC boats do well in this shorthanded configuration, except for 2019 where we saw Peter and David Askew and their team with an immaculately prepared VO70 Wizard win overall, but even so with some of the best smaller boats nibbling at their heels on corrected time. The 2021 Fastnet, starting in just under a year’s time, will see a new battle and a new challenge with the race finishing in Cherbourg, which will undoubtedly see even more French sailors joining the challenge – along with extra pressure in the shorthanded division. When I refer to more recent small French designs I am referring
to JPK, Sunfast, Archambault and so on, from designers including Joubert Nivelt, Marc Lombard, Daniel Andrieu and Jacques Valer. So why are the French sailors in these boats doing so well? These newer-style IRC boats have appeared at the request of
those French sailors and they are designed for offshore racing with shorthanded crew in mind. These sailors have grown up and trained for offshore racing and from the start they configure their boat and learn to sail it with fewer crew, exploiting the fact that on a race of several days one extra crew member is considerable additional weight when taking account of the extra equipment, food and water. Nowadays we rarely see a French boat competing in the Fastnet
with a full crew. It should be noted, however, that for inshore racing the results are not as good. We also note that in the Mediterranean the results are similarly not anything special, with the influence of different ranges of conditions and different racecourses. It is worth pointing out at this stage that the IRC two-handed cer-
tificate is for a boat configuration change only, for example different sails, ballast or stored power. The formulation does not change due to fewer crew as there are both benefits and disadvantages with less crew and IRC treats the boat the same as if fully crewed. There has been much talk suggesting that there is something specific or unusual about these French designs, maybe their bow
38 SEAHORSE
configuration or a smaller sail plan (sail area/displacement ratio), or their slab keels (with no bulbs), but on deeper analysis by the IRC technical committee such distinguishing characteristics have proved difficult to identify. One area to look at are bow and stern overhang measurements –
used to determine the waterline length with designers regularly attempting to trick the rule into assessing a shorter waterline length. However, IRC takes several measurements at the bow and stern and calculates a dynamic sailing length from a combination of this data. The plot of bow overhang against length of the most successful boats is nothing special, sitting firmly in the middle of the IRC fleet. The notable exceptions on our graphs (right) are the latest Sun-
Fast 3300 (Andrieu) and the one-off Nivelt A13 Teasing Machine (now Phosphorus II) with a greater aft longitudinal bow knuckle posi- tion (X measurement in IRC). This can reduce the dynamic sailing waterline in both reality and in rating terms but getting that balance right is not easy. Phosphorus continues to do well with her current owner Mark Emerson and his young crew picking up where original owner Eric de Turckheim and his professional French crew left off. The SunFast 3300 is a much newer boat but it has already enjoyed a number of big successes. We will watch her too with interest. The keel type of many smaller IRC boats, including the French
designs, has developed to a flat slab keel with no bulb as this is seen as advantageous, particularly offshore where the focus is on offwind performance and low drag. It’s worth pointing out that for 2020 the IRC formulation was tweaked to help transition ratings between different slab keel types and now uses a keel aspect ratio, leaving some of these boats with a small increase; but this year’s absence of racing means that this has yet to be tested offshore. There have been comments that these French-style designs have
a smaller rig with different sail area/displacement ratios – a deter- ministic factor for yacht power. But if we look at the aforementioned designs in a plot of upwind sail area/displacement ratio we again see nothing remarkable when compared to the IRC fleet as a whole. It is a similar story with the downwind sail area ratio. Generally
these French designs do develop a higher proportion of stability through the hull shape (as opposed to the weight of the hull or keel) and this is a designer choice. However, stability does not seem to pose an issue for the boats in a shorthanded configuration, driven also by the rig and sail selection. Faster and with less drag off the wind and with adequate stability racing upwind with a smaller crew, it’s clearly a successful formula. But not the only one.
PAUL WYETH
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