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.

10.11.2023

Serious damage to the steering system aboard the Maxi Edmond de Rothschild.

par Gitana

After 12 days of racing, the leading ULTIMs are attacking the home straight of their epic 7,500-mile course across the Atlantic and are currently sailing downwind towards the northern hemisphere, immediately adjacent to a large exclusion zone along the north coast of Brazil where navigation is not permitted. For the men on the Maxi Edmond de Rothschild, this final section of the race is set to be even more difficult than suspected since an incident that occurred this morning. In fact, since setting sail from Le Havre, on 29 October, Charles Caudrelier and Erwan Israël have not been spared of technical woes. As such, they have had to very quickly try to get the best out of a boat that was no longer at her full potential and adapt their race accordingly. This morning, an impact caused serious damage to the steering system and the sailors will have to contend with the major breakage all the way to the finish line, which is still some 2,000 miles away.

A repair procedure under study

This morning, shortly before 10:00 UTC, whilst the crew was making headway on port tack at over 30 knots, the Maxi Edmond de Rothschild’s suddenly lost speed, slowing to under 8 knots. This sudden stalling was the result of an impact a few seconds earlier. Charles Caudrelier and Erwan Israël quickly noticed that the steering system had been seriously damaged. Indeed, with the impact, the steering arm broke. This is part of the system that connects the central rudder to the float rudders.
After a thorough inspection and discussions with his shore team, the skipper of Gitana Team had to face facts: such a breakage is hard to repair at sea, even though the team is not giving up and is currently working on a procedure with the crew to effect repairs. It should be noted that this incident comes on top of some previous issues because, in the opening miles of the Coffee Route, the crew encountered some difficulties with the steering system on their flying maxi-trimaran. Here it’s worth recalling the two rather spectacular bear aways at the start off Normandy. With this system undermined, the giant is very tricky to steer on port tack.

If no repair is possible, it is in this new configuration, with only the rudder on the central hull working, that the five-arrow giant will have to make landfall in Martinique.

This damage some 2,000 miles from the finish in Fort-de-France is a tough blow for Charles Caudrelier and Erwan Israël, who have been slugging it out in the top trio since the start in Le Havre on 29 October. For all that, the two sailors are determined to finish this Transat Jacques Vabre. The Maxi Edmond de Rothschild’s performance will naturally be affected and this is bound to be reflected in the speed of progression. However, the duo is adamant: “We will fight for this third place right to the wire with all the weapons we have left at our disposal.”

Position report on 10 November, 14:00 hours

1) Maxi Banque Populaire XI – Armel Le Cléac’h / Sébastien Josse at 1 741 miles from the finish
2) SVR Lazartigue – François Gabart – Tom Laperche at 50,8 miles from the leader
3) Maxi Edmond de Rothschild – Charles Caudrelier / Erwan Israël at 254 miles
4) Sodebo Ultim 3 – Thomas Coville – Thomas Rouxel at 577,7 miles
5) Actual Ultim 3 – Anthony Marchand / Thierry Chabagny at 704,4 miles

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