Not ready for steady flight

The 60-foot IMOCA has evolved into a high-flying offshore boat as sidefoils reduce displacement and increase speed. But foiling boats perform best with a balance of lift surfaces to provide steady flight, and that was the debate for the IMOCA Class:

It was at the Annual General Meeting (AGM) of the Class where members voted on a revision of the one-design mast which aims to increase safety coefficients, possible new rules on engine size, limits to the number of sails carried during races and other technical measures and improvements.

But the biggest discussion point was on the issue of T-foils on rudders which would convert IMOCAs from skimming boats with foils to even faster fully flying ones.

Those in favor of the change say it would be within the spirit of innovation that is a cornerstone of the IMOCA Class’s philosophy, that the change can be made simply and that it would greatly improve the level of comfort for skippers as they fly above the waves.

Those against, meanwhile, point to the likelihood that T-foils would lead to big changes in the way boats are built, to cope with the extra stresses and speeds, and that masts would have to be re-designed amongst many other changes which would make this additional capability expensive to implement.

Antoine Mermod, the President of the IMOCA Class, said the collaborative spirit and level of debate was very impressive from the group. He said this latest decision will not be validated and confirmed until next April when the Class rules up to 2029 will be confirmed.

“Having this meeting, with most of our teams having input and sharing in the debate, is the right way to build something stronger because it is a long process to establish good rules and find the right balance that will then be accepted by most of the teams,” he said.

Mermod said the issue of T-foils was a complex one with many elements to consider.

“When you choose the next step – the next innovation – it’s quite easy to feel what it might be, but the problem is more about when you do it than what it is,” he explained. “If the Class is enjoying a successful period in its evolution, then sometimes it is good to make it stronger incrementally and to make changes at the right time, more than being led by technical innovation.”

The switch to fully-foiling may happen, Mermod argues, but the key issue is when that is.

“For sure, at one point the goal will to be go around the world by flying over the waves – which is fantastic – but to do it in the best conditions, is that now or a bit later?” he questioned.

“When you hear all the arguments that were put forward at the AGM, they are all good actually and all the speakers were right in what they said. But, if you see the group as a whole, people are considering if this the right time or not and that’s why the vote on this is something strong.”

Source: IMOCA