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.

11.11.2017

The Maxi Edmond de Rothschild in ambush.

par Gitana

The Inter-Tropical Convergence Zone, which the Edmond de Rothschild duo entered yesterday evening at 8° North, was not a mere formality. In all probability, less sluggish than their competitors in the squalls, Sébastien Josse and Thomas Rouxel made the most of their 6th night at sea to close the gap in relation to Sodebo Ultim’. At the 12:00 UTC position report, with the exit from the doldrums taking shape, the Maxi Edmond de Rothschild was positioned just 7.4 miles astern of the leader of the Transat Jacques Vabre. The race is certainly living up to its promises and, as the sailors keep repeating during the audio sessions, the battle being fought just a few miles from the southern hemisphere is absolutely thrilling.

Doors to exit

For the past few days, the night phases have seemed to turn to the advantage of the Josse-Rouxel duo. Indeed, from Thursday night through into Friday, Gitana 17 made up half the deficit in relation to her adversary thanks to better positioning on the Atlantic chessboard. Last night, the wind gods showed a gentler side to the two sailors from Gitana Team, enabling them to better negotiate the pitfalls of the doldrums. At daybreak, the Maxi Edmond de Rothschild was back to within 4 miles of Sodebo Ultim’.

Antoine Koch, the onshore router for the five-arrow team, described the conditions encountered last night by Sébastien and Thomas: “The doldrums configuration proved to be fairly classic for the season. They initially entered a zone of squalls with streets of clouds all nicely lined up and moving with the easterly wind. The game plan involved following the line of clouds, accompanying them and then moving from squall to squall to get the best of the slightest puff of breeze. At the end of this first zone, they hit a wall of cloud. At that point, the squalls had much more punch, with fairly strong wind picking up quickly. It was a phase where they had up to 25 knots. That’s where the complexity of this zone hits home. It requires a quick reaction time and a high level of physical engagement, with a huge amount of manœuvres, which are difficult due to the sheer scale of these big machines. After this band of strong wind, the breeze usually backs as it eases. That’s potentially where the much-dreaded erratic winds can strike. In our case, the wind never dropped below 8 knots and it even increased fairly quickly to around 12-13 knots. Gitana 17 never came to a complete standstill, which is fantastic news. Since this morning, the wind has been a bit more stable, veering a little more, and already there are the early signs of the south-easterly trade wind. The exit is very close!”

The southern hemisphere in their line of sight

This Saturday 11 November, Armistice Day, the atmosphere in the Atlantic is more one of fighting being resumed. The equator, this imaginary demarcation line between the northern and the southern hemisphere, might well take on the form of a restart in this Transat Jacques Vabre 2017. Still nearly 300 miles ahead of them at noon today, the two crews should make the switch to the southern latitudes midway through tonight. The lights of Salvador de Bahia will then be just 900 miles in front of the bows of these two driving forces at the head of the race.

Ranking at 11:00 UTC, Ultime category – Saturday 11 November

1 – Sodebo Ultim’ – 1,214.6 miles from the finish, 19.5 knots over 1hr
2 – Maxi Edmond de Rothschild – 1.9 miles behind the leader, 22.2 knots over 1hr
3 – Prince de Bretagne – 873.7 miles behind the

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