Retractable Y-shaped foils, adjustable in three dimensions

Inspired by the appendages of the America's Cup foiling monohulls, these Y-shaped foils have a wingspan of over 5 metres. They are designed to generate powerful lift, increase power and offer a wide range of adjustments to optimise flight at every point of sail and in all conditions. Beyond their impressive size, these foils feature many unique innovations.

Revolutionary U-shaped rudders

These are probably the most visually striking innovations on the new Maxi Edmond de Rothschild. To fly high above rough seas while maintaining control, the team wanted very long rudders that would remain in contact with the water. The challenge is that longer rudders tend to flex under load, severely affecting steering and the efficiency of their lifting surfaces. A new geometry was needed to give these appendages maximum stiffness, resist cavitation and ultimately improve control of the boat and make better use of its power. The result is a set of U-shaped rudders over 4 metres long, a metre longer than those on Gitana 17. Their shape, reminiscent of a tripod or an inverted π, is only the visible part of what makes them so distinctive.

A daggerboard optimised to stabilise the boat and limit cavitation

With its wide span, the daggerboard resembles an aircraft tail assembly, with two adjustable flaps: one on the vertical section and the other on the horizontal section, the distinctive “manta-ray wing”. On Gitana 18, the innovation is to position this wing behind the vertical part of the appendage, rather than directly beneath it, to minimise flow disturbance and cavitation.

Rig: adjustable spreaders to control mainsail power while sailing

Gitana 18’s mast is 1.50 metres taller than its predecessor’s. The boom is also shorter, creating a more slender sail plan. The major innovation is a set of spreaders that can be adjusted while sailing to bend the mast fore and aft. Actuated by hydraulic rams, these spreaders can pivot through 35 degrees to adjust the bend in the middle of the mast. This unprecedented system allows the sailor to control mainsail power: adding depth in light winds to take off sooner, or flattening the sail to reduce power at high speed or in strong winds. Adjusting the depth, and therefore the power, of the mainsail can also save a solo sailor time and energy by reducing the need for risky manoeuvres or headsail changes.

Central hull:
an integrated, structural coachroof

The naval architects and Gitana design team wanted an exceptionally stiff, structurally robust platform. This applies both to the floats, which must withstand heavy loads from the foils and rudders, and to the central hull, which is subject to torsion. The enclosed coachroof is integrated into the hull and contributes to its structural strength. Inside, the cockpit brings all sail-handling controls together, with ergonomics shaped by many hours of design and development. The coachroof also stands out for the number and size of its windows. This configuration meets the visibility requirements of the Ultim class rules and gives sailors the best possible view to keep a visual watch.

06.11.2023

Beating towards Ascension.

par Gitana

Yesterday, the ULTIMs celebrated their first week of racing in the Transat Jacques Vabre 2023. However, now is not really the time for celebration aboard the Maxi Edmond de Rothschild. For Charles Caudrelier and Erwan Israël, the hours spent in the doldrums have been particularly gruelling both physically and in terms of the ranking. Since then, the Gitana Team duo has put this tough passage to the back of its mind and has been able to make the most of the more favourable conditions to recharge their batteries and get back on the hunt. Third this Monday evening, theoretically around thirty miles shy of the firm leader, the Maxi Banque Populaire XI, they are continuing to apply themselves and take it in turns with the trimming to optimise the trajectory and speed of the five-arrow giant.

Since yesterday, the fleet of giants has been sailing in the southern hemisphere. Having left to port the course mark of São Pedro e São Paulo, a group of rocks and reefs rising up out of the North Atlantic some 1,000 kilometres to the north-east of the city of Natal, the ULTIMS have one by one crossed over the equator into the southern latitudes. Right now, they’re close-hauled in the SE’ly trade wind, beating towards Ascension Island, the next course mark to round before they set a course towards the finish in Martinique.

Watch the video

A very sticky doldrums

Contacted at the radio link-up on Saturday morning, Charles Caudrelier announced: “Today, the doldrums look fairly easy, but according to the latest observations the clouds are not very dynamic.” However, well honed in the exercise of negotiating the Inter-Tropical Convergence Zone, thanks in particular to his past round the world passages, the skipper didn’t forget to use the conditional tense, which is essential in the doldrums: “Our boats can negotiate the doldrums very quickly. If there’s just a sniff of breeze, we can very quickly pick up the pace to 20 knots and we don’t have to endure a rather laborious 300 miles for half a day. We can also take double that time or worse if there’s no breeze though. It can be a whole different ball game depending on your passage time. Things change very quickly from east to west in this zone so you have to monitor the on-board radar and the satellite images from our routing cell. There are no magic solutions in the doldrums and experience does not give you any greater certainty.”
Indeed, not everything went to plan in the end! Back to within twenty miles or so of Banque Populaire’s stern, with SVR – Lazartigue slowly making headway further to the west, the men of Gitana Team could only watch as the exit door got further away from the Maxi Edmond de Rothschild’s bows, just like their rivals, all thanks to an unfortunate cloud developing above their masthead: the famous squalls synonymous with this area! Getting free of its clutches proved both long and laborious. Despite the inconvenience, Charles Caudrelier remained philosophical yesterday: “That’s how it goes, sometimes you win, sometimes you lose… that’s the name of the game in the doldrums!”

The entire fleet back out on the racetrack again tomorrow

Over recent days, France has been swept up in a series of autumnal storms, the intensity of which has forced Race Management in the Transat Jacques Vabre to revise its initial plans. Though the five ULTIMS were able to set sail as planned last Sunday and then dive southward before the arrival of the first depression, Ciaran, and continue on their way without interruption, the other fleets have not enjoyed the same conditions. Indeed, despite also departing Le Havre on 29 October, the Ocean Fiftys and Class 40s have sought refuge in the port of Lorient, Brittany throughout the past week. This morning, at 09:30 UTC for the trimarans and 09:45 UTC for the monohulls, it was finally time for them to rediscover the open ocean. The exchanged smiles in the early hours of this morning, dockside in Lorient La Base, spoke volumes about the eagerness of the forty-six duos to get back out on the racetrack. Tomorrow, it will be the turn of the IMOCAs to cast off. They’ll leave the Bassin Paul Vatine in Le Havre very early for a start off Cap de la Hève at 08:30 UTC.

Position report on 6 November, 18:00 UTC

1. Maxi Banque Populaire XI some 3,781.7 miles from the finish
2. SVR – Lazartigue + 27.5 miles
3. Maxi Edmond de Rothschild (Charles Caudrelier / Erwan Israël) + 31.8 miles
4. Sodebo Ultim 3 + 141.8 miles
5. Actual Ultim 3 + 193.9 miles

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