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.

15.11.2008

A combined attack at the approach to Cape Verde.

par Gitana

For the twenty-six competitors in the Vendée Globe 2008-2009, the descent towards the equator continues but the rhythm has changed pace. Indeed the periods spent slipping along downwind in steady tradewinds of between 20 and 25 knots have given way to more gentle sailing in an easing breeze of around ten knots. The reason for this is a ridge of high pressure which is stretching out towards the SW. Still holding onto pole position after three days, Loïck Peyron and the monohull equipped by Baron Benjamin de Rothschild continues to be tailed by Jean Le Cam and Sébastien Josse, respectively 14.8 and 23.1 miles astern at the 1600 hour ranking.

This Saturday afternoon, the voices of the solo sailors sounded clearer and less exhausted at the daily radio session from Race HQ, based at the foot of the Tour Montparnasse. “The sea is calmer. There is a blazing sunshine and not a cloud in the sky. The temperatures are climbing and the fleeces are coming off!”, announced Loïck Peyron. The sailing conditions experienced by the head of the fleet on this sixth day at sea, are finally enabling the sailors to think about themselves: washing themselves, washing their clothes and tidying up are all on the programme! “I’m tidying up and I’m preparing for the coming week, which should be one of the hottest of our circumnavigation of the globe. The sea state has enabled me to perform some checks for wear after nearly a week’s sailing. I still have to check the rig so I’ll be treating myself to a little climb up the mast”. However, just so we know what’s what, although life onboard has switched to a calmer mode, the gentler pace currently being experienced by the leaders is a long way off being a long, tranquil river: “the wind is very shifty and variable in terms of strength and you really had to be on top of the trimming last night to get the ‘baby’ making headway. After this the conditions will become a little too calm to feel calm about it!” admitted the skipper of the monohull in the colours of the LCF Rothschild Group.

Indeed, those leading the way are currently sailing close to a ridge of high pressure and the NE’ly tradewind is starting to get out of breath. This change of pace already looks set to cause a tricky passage around the Cape Verde islands, as the skipper of Gitana Eighty confirmed at midday: “According to the different options, we should see to some minor tussles around the islands of Cape Verde.” There is a strong chance that the fleet will have to weave their way around them which will require concentration and lucidity!

Leading the way for the past three days, Loïck Peyron is tracking southwards, without worrying too much about the trajectories of his rivals for now. Although there is still some lateral separation, the courses of the Imoca monohulls are tending to converge; an observation which could prove the words of the skipper of Gitana Eighty right: “Within a few days time we should pretty much all end up in the same area!”

This 6th edition of the single-handed round the world without assistance is living up to all the expectations of the observers: bunched together as they would be in a transatlantic race, the solo sailors are putting on a fantastic spectacle and are an inspiration to the admiring landlubbers.

Ranking on 15th November – 1600 hours (French time)
1. Gitana Eighty (Loïck Peyron) 21,948 miles from the finish
2. VM Matériaux (Jean Le Cam) 14.8 miles from the leader
3. BT (Sébastien Josse) 23.1 miles
4. Paprec Virbac (Jean-Pierre Dick) 31 miles
5. PRB (Vincent Riou) 44.2 miles
6. Brit Air (Armel Le Cléac’h) 53.1 miles
…

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