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.

01.11.2010

Wave hopping in the Bay of Biscay.

par Gitana

The first night at sea is now in the wake of the eighty-five solo sailors in the Route du Rhum, as is the first route selection on rounding the tip of Brittany; especially for the nine ‘ultimate’ multihulls who are leading the way. Aboard Gitana 11, Yann Guichard has nicely adjusted his trajectory since leaving Saint Malo at 1302 hours yesterday, but for the time being he’s finding himself penalised by short, big seas associated with an established N to NW’ly breeze of around 25 knots. Such weather conditions are forcing the skipper of Gitana Team to ease off the pace to spare his steed. At the first position report of the day, the maxi-trimaran fitted out by Baron Benjamin de Rothschild was positioned in 5th place with a deficit of around forty miles on the current leader.

We sensed it yesterday evening on observing the cartography: four of the top five competitors in the Ultimate category have opted for a S’ly course, diving down into the Bay of Biscay, whilst for now solely Sydney Gavignet seems to be favouring a trajectory closer to the great circle route (direct route). And among this foursome currently heading for the headland of Finisterre, three have opted to pass between Ushant’s Traffic Separation Scheme and the island of the same name. This was the choice made by Yann Guichard and Sylvain Mondon. Here it is worth noting that the TSS is a protected perimeter which takes the form of shipping lanes. Its aim is to keep the large commercial shipping away from the coast. For obvious safety reasons, taking so-called pleasure craft into these navigation zones is strictly forbidden.

As forecast, the first night for the solo sailors hasn’t been a restful one at all. Since the start, aboard the 23.50 metre maxi-trimaran, Yann Guichard has linked together a series of manœuvres with no less than seven gybes and a change of sail plan on rounding the island of Ushant. Such constant work enabled the sailor little respite. However, the skipper of Gitana Team, who has the most suited boat for this type of exercise as it is much more manoeuvrable than those of his rivals, has certainly come off the best in this very physical introduction to the race.

After the mild conditions at the start of the race, the solo sailors are now into the thick of the action as they pass the tip of Brittany: an established breeze of between 20 and 25 knots and above all big, short seas which aren’t very favourable for making rapid progress. Fortunately though, the fleet of the Route du Rhum 2010 are passing through the zone on the back of a big system. Indeed Yann Guichard and his playmates are arriving on zone behind a very active low, which has traversed the Bay of Biscay and will pass over France in the coming hours. This disturbed air flow led to 10 metre waves to the North of La Coruña yesterday morning, whilst the wind was gusting in excess of 50 knots…

Though the weather forecasts are holding true on the race zone, around 25 knots of breeze – 30 in the gusts – was hitting the fleet shortly after 0400 hours this morning, the wind is set to become slightly more intense, peaking at 33 knots. However, it is forecast that the N-NW’ly air flow will very rapidly settle down at daybreak. The trend observed at the first position report of the day, namely a Gitana 11 less at ease and less speedy than her rivals in these wind conditions and heavy seas, is set to continue for a few hours, before the situation is reversed with the calm conditions expected at around 0700 hours this Monday morning.

Ranking for the Ultimate Category on 1st November at 0400 hrs
1. Sodebo
2. Oman Air Majan à 5,5 miles
3. Groupama 3 à 31,5 miles
4. Idec à 36,4 milles
5. Gitana 11 à 43,3 miles
6. La Boite à Pizza à 77,3 miles
7. Défi Cancale à 89,5 miles
8. Saint-Malo 2015 à 105,7 miles
NL. Côte d’Or II

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