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.

18.02.2024

2,200 miles to Brest.

par Gitana

This Sunday 18 February at 12:30 UTC, Charles Caudrelier began his seventh week at sea in the Arkea Ultim Challenge. Setting sail from Brest forty-two days ago, the Maxi Edmond de Rothschild passed the latitude of Cape Verde early this morning. This afternoon, the leader of the round the world for ULTIMs is making headway at 21° north and benefiting from around fifteen knots of NE’ly wind to post an average speed of 25 knots, close-hauled in a trade wind sea of 2.5 to 3 metres. Since crossing the equator on Friday morning, the skipper of Gitana Team has made no secret of the fact that this long tack northward towards the Azores is a tad monotone. This is especially true after six weeks of racing and some 2,000 miles from the finish, when the urge to reach the finish line is increasingly strong. However, Charles Caudrelier is remaining pragmatic because having scanned the latest weather forecasts, he knows that the end of the course promises to be tough and particularly windy.

In race mode

42 days… the solo round the world record under sail, which was set by François Gabart in 2017, will not be beaten. Up to the halfway mark in the Arkea Ultim Challenge, Charles Caudrelier was very much inside the record time and even a few hours ahead of schedule on passing South-East Cape in Tasmania at the exit from the Indian Ocean. However, the weather sequence in the Pacific, with forty-eight hours on stand-by shortly after Point Nemo and a particularly slow South Atlantic put the stopwatch to the bottom of the list of priorities. For the skipper of the Maxi Edmond de Rothschild, this is in no way a disappointment. In fact he insists: “I’m racing. It’s first place that I’m interested in, not the rest!”

Charles Caudrelier, 18 February

“The fastest routing has us finishing on Thursday evening or Friday, but we have slightly complicated weather at the end, so we’ll have to decide if we become embroiled in the weather system or sit it out for a bit to let the worst of it roll through. The weather for the end of the week is shaping up to be pretty boisterous, with very heavy seas. Either way, I hope we’ll finish by the end of the weekend.
François Gabart’s record will not be beaten, but that was not my objective on a personal level. I’m in a race, not a record attempt, and I didn’t choose my weather window. Racing is a whole different ball game. There is some strategy involved in relation to adversaries and that changes everything. Prior to Cape Horn, when we had to stop for 48 hours to let the bad weather roll over us, it was an easier decision to make because we were in front with a sizeable lead over the 2nd boat. During a record attempt, you know the course and your rival’s schedule. That really changes the deal in terms of the way you tackle your own navigation.
On paper, the Maxi Edmond de Rothschild has greater potential than Macif did at that time as we are flying around the world. However, what is notable on this course is that the weather is much more important than the potential of the boat. Record times, like the one for the Saint Exupéry in solo format or the crewed Jules Verne, are so low today that you need a perfect sequence of weather systems to beat them.”

Ranking at 16:00 UTC

1/ Maxi Edmond de Rothschild – Charles Caudrelier
2/ Sodebo Ultim 3 – Thomas Coville – 2,263.5 miles behind the leader
3/ Maxi Banque Populaire XI – Armel Le Cleac’h – 2 578,2 milles behind the leader (on a pit stop in Rio) 4/ Actual Ultim 3 – Anthony Marchand – 5,940.8 miles behind the leader
5/ Ultim Adagio – Eric Peron 6,468.1 miles behind the leader

Abandon SVR Lazartigue – Tom Laperche

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