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.

18.11.2005

I’d sail a thousand miles….

par Gitana

Gitana 11 still has one thousand miles to sail in the home stretch to the finishing line in Bahia. A straight line course which could be broken by a gybe to get bang smack on track. And a chance to catch up on current leader Banque Populaire. One and a half days to the finish and the final order is still uncertain. Gitana X is making her way down to Ascension Island, a long and laborious battle head to wind. Another day and a half in the same style before hoisting the gennaker and finishing downwind Bahia bound.

A thousand nautical miles, one fifth of the course in the Transat Jacques Vabre, but the last 20% is reeled in just two days! The going in the South Atlantic is much more comfortable altogether once past Ascension Island forcing the fleet to sail close-hauled against steady trade winds and short seas. Faster now too! A 450-mile day is not unusual. That could increase to covering as much as 500 or even 520 miles in 24 hours. A nice long line to plot on the chart! Boat speeds averaged more than 23 knots today, so the going was easier today. Crew’s attention is still intensely focussed on sailing the boat fast. The sun is out, temperatures are much warmest, a steady SE/E breeze is blowing at around 18-20 knots and seas consistent. Nothing like the last three days spent pile-driving through wild seas.

Conditions described above apply to Gitana X. After having stopped twice in Porto and then in Lanzarote, Thierry Duprey du Vorsent and Erwan Le Roux only shook their steed free of the Doldrums on Thursday and since then have been plunging south towards Ascension Island. And that is the most unpleasant part of the 5 190 mile long course which should come to an end for the tandem on Saturday. But they have not been contacted by telephone over the last couple of hours. Same goes for Frédéric Le Peutrec and Yann Guichard. Race HQ in Bahia have not been able to get in touch with them recently either.
But it is easy to imagine that the pair on the « Eleven » is busy pushing its racing machine as hard as they can, mainsail and gennaker flying high. Not only is Gitana 11 sailing fast, she is also trying to gain to windward as an offensive move on the leader. They should be able to snatch back a few tens of miles by gybing north on Saturday around midday as the trade winds gradually start to turn east. Perhaps the last chance for a real offensive move before the landfall in Brazil. If this strategy does come off, Frédéric and Yann could represent a much more serious threat in the last few miles, where the wind could become lighter, change direction, or cease blowing altogether. If they manage to come within 30 miles of Banque Populaire by midday on Saturday, they could even stand a chance of winning. Finishing at night time in Bahia’s All Saints’ could then be critical – the climate changes dramatically. Factors such as wind angle could upset the hierarchy altogether at the very last minute. Patience, patience… a day and a half from now

Rankings – Friday 18th November 2005 at 16h00 :

1-Banque Populaire : 952 ½ miles from the finish
2-Gitana 11 : 1 027.9 miles from the finish
3-Géant : 1 094.9 miles from the finish
4-Gitana X : 1 904.1 miles from the finish

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