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.

27.02.2008

A game of cat and mouse towards San Francisco.

After setting out six weeks ago in the conquest of a record never before coveted by a maxi-multihull of Gitana 13's dimensions, Lionel Lemonchois and his nine crew are experiencing their final hours at sea on this Route de l'Or. However, the weather situation currently reigning off the American coast, is forcing the men of Gitana Team into a series…

par Gitana

After setting out six weeks ago in the conquest of a record never before coveted by a maxi-multihull of Gitana 13’s dimensions, Lionel Lemonchois and his nine crew are experiencing their final hours at sea on this Route de l’Or. However, the weather situation currently reigning off the American coast, is forcing the men of Gitana Team into a series of tacks, upwind, to reach their final destination. A configuration, which will require them to cover some extra miles.

In the guise of a final sprint, the crew of Gitana 13 are weaving their way towards San Francisco. “We are trying to gain the maximum of northing in order to make headway along the course, but the weather conditions are forcing us to tack” explained Dominic Vittet from the chart table of the 33 metre catamaran.

Trapped between two very different weather situations, Lionel Lemonchois and his men have had no option but to zigzag from one to the other: “To our West? There’s a zone of high pressure synonymous with light winds, whilst to our East a corridor of steadier winds has formed along the coast. The aim over these final 24 hours is going to be to successively play these two phenomena off against each other. The direct course is guiding us northwards, but as soon as the wind eases too much we put in a tack to regain more pressure. Then as soon as the wind fills in again, we make for the edge of the zone of high pressure again… and vice versa” resumed the onboard navigator.

These numerous manœuvres are not hampering the organisation of the watch system aboard Gitana 13 however, the latter a very well oiled machine after over 41 days at sea, as Dominic Vittet confirmed: “We’re fully into the rhythm and we are still applying our system of three watches of three crew, which rotate on deck every three hours. Off watch, dedicated to the weather and the optimisation of Gitana 13’s trajectory, I nevertheless take part in the 0900 and 2100 hour watch in order to relieve the crew who are permanently on watch.”

The maxi-catamaran equipped by Baron Benjamin de Rothschild is still expected into San Francisco on Thursday morning, where it will cross the finish line situated just off the infamous prison of Alcatraz.

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