L'Imoca de Sébastien Simon au départ du Vendée Globe

What you need to know about the new IMOCA rule

The new Imoca rule which will be applicable from 2022 to 2025, was voted on at the class association’s general assembly on April 15. To understand the main developments, Tip & Shaft interviewed the class president, Antoine Mermod, the architects Quentin Lucet and Sam Manuard, skipper Stéphane Le Diraison and also Pierre-François Dargnies who is the technical director of the Charal Sailing Team (all are members of the technical committee which worked on the subject), as well as speaking to skippers Fabrice Amedeo and  Kevin Escoffier and David Sineau who is the team manager of Initiatives Cœur.

An evolution, not a revolution“, is how Antoine Mermod has described the rule changes,  explaining: “We have an existing fleet which was proven to be reliable on the 2020 Vendée Globe with boats which importantly still have room for improvement, the idea was therefore to avoid promoting a required technological breakthrough.”

Like, for example, the potential and widely called for authorization of foil planes on the rudders which would have allowed the Imoca to properly sustain flight. From the general assembly of August 2020, it was decided to postpone the adoption of these T-rudders. “Personally, I had voted for them because I did not want to be holding back the big teams and I was I was saying that to innovate is in the DNA of the class,” explains Fabrice Amedeo. “But when we see the scenario of this 2020 Vendée Globe fortunately we did not vote for them, so let us further digest big foils and the resulting life on board, and we’ll see for 2028.”

Foils were naturally central to the debates over the 2025 rule. When the principle of their limitation was adopted in August the objective is to avoid continued technological escalation – an arms race –  and to contain costs, but the framework actually then needed to be specified. Should the criteria be the weight, the price, the volume and/or the manufacturing process that is limited? In the end, it was the volume criteria that was chosen, but again, it was necessary to agree on the limit not to be exceeded and on how to calculate it, resulting in endless discussions.

The limit of foils in question

“The debates revolved around the upper limits in particular,” explains Quentin Lucet, whose VPLP firm is notably designing Boris Hermann’s future Malizia 2. “Some argued for it to be equivalent to the volume of the largest foils built so far, others wanted to lower it significantly, which suddenly dropped some boats out the rule. In that case, should they be asked to re-size their foils? It was quite complex.”

Finally, the figure of 8 m3 was adopted, only really affecting the foils of L’Occitane (now Bureau Vallée 3 – 9.6 m3) and Arkéa Paprec (12 m3), which will benefit a grandfather rule. They will be able to continue using their existing appendages, but will have to comply with the new rule if they build new ones. The chosen solution is relevant, comments Sam Manuard, the architect of the future Charal 2. “A lot of boats have foils just a little above that limit but they can easily comply either by cutting the tip a little, or by limiting the extension.”

Pierre-François Dargnies wonders: “It is good to have fixed these limits because it was necessary to avoid going crazy, but in terms of the cost and the construction time we should perhaps have limited the construction process, because depending on which route you choose, the price difference can be 150,000 euros. For Charal 2, we had aimed at around 350 000 euros the pair but we could not manage to hold to that and we are more than 500,000 and everyone will go down this path. If you limit the processes you certainly limit the geometries a bit, but you still leave everyone with more freedom than with one-design foils. However, I’m afraid that in four years, we will switch to one-design foils given the explosion in budgets. “

Reworked….. one-design foils

Kevin Escoffier was seemingly one of the only ones to be in favour of one-design foils “In view of the specifications looking to cost reduction, reliability and reduction of the impact on the environment, I found that it was a good solution, because it also made it possible to make wells and a one-design angle adjustment system, but also for older generation boats to be able to put foils on at a lower cost.”

Asked about this, Quentin Lucet replied: “The one-design foils really would have greatly constrained architectural creativity by leading to a great deal of convergence of the hulls. The diversification of concepts is also what strengthens interest in the Imoca class.”

Another proposal that has not been passed is that of the Initiatives Cœur team to limit the teams to a single foil design over four years. In the end two designs were authorized and three for those participating in The Ocean Race. “For the 2020 campaign, changing the design did not really help: some teams went back to their V1, others broke their V2, I think we can be more reasonable with the first design and live with one in a campaign,” said David Sineau.

Standardization advances

Sineau, the Initiatives Coeur team manager was also promoting the idea of one-design rudders, a proposal that was again rebutted: “Nothing looks more similar on the boats, one to another is the rudders. It is a shame to devote a lot of resources to them when in terms of innovations there is not much difference.”

For Antoine Mermod, the timing was just not right: “When you put in place standardized elements, it’s for 6-8 year hences, or if we move to promising designs in the near future, it seems difficult to adopt a solution today which might last only two years. On the other hand, the proposal of a standardized T-rudder could indeed be a logical step.”

Last August’s General Assembly also decided on standard foil wells, a solution that was not in fact adopted this mid-April: “It had big advantages, in particular to be able to interchange the foils between the boats, but we reversed the idea because it posed significant technical problems of implementation on certain boats, so that risked increasing the cost of the wells. As long as we do not converge towards a design of the foil which will end up becoming the reference, it it is a bit early to standardize the well,” adds Antoine Mermod.

Standardization is gaining ground, however, since in addition to the mast, sail and keel rams, which were already one-design, it is now the turn of the boom, the J2 forestay and runners. Will this reduce costs? “It’s attractive in principle, but in practice, we can see, for example, that the one-design mast did not cost less,” answers Stéphane Le Diraison. “But, fair play, on the other hand, it gives guarantees to our insurers and our sponsors, it is not nothing to tell them that these are costs and equipment which are controlled in terms of reliable specification and development.”

Electronics, more standardised too

Always with the aim of limiting costs, on-board electronics were also at the centre of the discussions“The budgets are exploding completely, and over-sophistication seems a little exaggerated to me, but a lot of people think on the contrary that it is necessary to keep the electronics field open and free because it is performance gain, which is also true”, comments Sam Manuard.

The solution ? For sensors and devices with a commercial value of more than 10,000 euros (gyro-compass, inertia units, etc.), an evolving permitted list of equipment will be authorized. “The costs have certainly increased a lot, but the quality, in particular of the pilots, has made a huge leap.” explains the president of Imoca. “So it is important to continue working on these subjects with very high added value for reliability and safety. Ditto for the sensors: it is expensive to measure and analyze the data, but it makes it possible to better understand and anticipate damage and this benefits the entire fleet.”

Sustainable development, a real step forward or window dressing?

Another evolution of this 2025 rule is the topic of sustainabilty with various rules, as a weight credit of 100 kilos for the use of bio-sourced materials on non-structural elements, a compulsory life cycle analysis for all new construction, the obligation to embark on a green sail, a charter of good conduct…

So many measures that left Kevin Escoffier saying: “I am not sure that the concept of sustainable development in itself is compatible with the very principle of competition in a mechanical sport but these are the first steps.” Sam Manuard is firm on the subject: “You can talk all the nonsense you want, but there is nothing really sustainable about development in ocean racing, I do not know a mechanical that can promote this concept. I think that if we really wanted to take this super important social issue into account, we would have to review everything from the start, agree to sail slower and create a new class of boat.”

Still, some are trying to move forward in this direction, such as Stéphane Le Diraison who wants to return to the Vendée Globe “with a carbon-free boat to show that we are capable of integrating the environmental aspects while preserving performance and the economic model. The source of inspiration is the Class40: when you see the speeds reached by the boats when they are 12 meters long, are made of fiberglass and have a fixed keel, that gives you food for thought.”

Photo: Jean-Marie Liot / Alea

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