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.

26.01.2008

Putting on the brakes.

The maxi-catamaran fitted out by Baron Benjamin de Rothschild left New York on 16 January in attempt to beat the record on the prestigious Route de l'Or. Gitana 13 entered its 10th day of sailing at the end of the afternoon today. But if Lionel Lemonchois and his crew had hoped to make good time in the southern-hemisphere trade winds, current condi…

par Gitana

The maxi-catamaran fitted out by Baron Benjamin de Rothschild left New York on 16 January in attempt to beat the record on the prestigious Route de l’Or. Gitana 13 entered its 10th day of sailing at the end of the afternoon today. But if Lionel Lemonchois and his crew had hoped to make good time in the southern-hemisphere trade winds, current conditions are not cooperating. The boat’s average speed in recent hours has been below 10 knots.

Re-thinking the strategy

Until yesterday, Gitana 13’s strategy was to avoid a developing stormy low-pressure system off the coast of Rio de Janeiro by moving farther from the Brazilian coast and skirting the eastern side of the disruptive weather system. But the changing weather forecast has led Lemonchois and Dominic Vittet, who together determine the strategy, to revise their plan. “Given the eastward progression of the storm system and the position of the Saint Helena high-pressure system, which is more sprawling during the southern summer, we decided in the end to go west,” said Vittet, the onboard navigator.
To top things off, in addition to barring Gitana 13’s route, the low-pressure system has disrupted the southeastern trade winds, thereby complicating the ten sailors’ task. Lemonchois and his crew are now experiencing a weak, unstable breeze, and their speed has dropped significantly in the past few hours. This situation is expected to last through the weekend.

This slowdown should not affect the maxi-catamaran’s projected date for rounding the legendary rock at Cape Horn: on or around 2 February.

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