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.

11.11.2002

Mast damage aboard Gitana X.

At 18:30 French time (17:30 GMT), Lionel told the Gitana Team, on watch in La Trinité-sur-Mer, that the upper part of the mast had just broke while Gitana X was sailing upwind with a reefed main sail and the small jib, with 20 to 25 knots of south-westerly wind.

par Gitana

Lionel had been on a port tack for about an hour, following an excellent 290° course and sailing along on a near-perfect route to tackle tonight’s expected low pressure system. Before sunset, he had even set the removable forestay (cable) which would have allowed him to hoist a storm jib (ORC) if the wind was to increase. The sea was beginning to grow heavier, with waves reaching approximately 3 meters. Gitana was sailing at about 12 knots of average speed.
The spar broke approximately 7 meters below the mast head, right at the top of the mainsail (which had two reefs), and below the staysail stay fixation point. No explanation can be given so far concerning this mast breakage.
Lionel managed to secure the broken part onto the undamaged mast portion and started to head back home, downwind, towards La Trinité-sur-Mer (Atlantic Coast), about 200 miles (370 km) away.
At 20:00 French time (19:00 GMT), Gitana was positioned at 46°35’04” N and 07°07’00” W (almost right at the middle of the bay of Biscay), on a 64° heading, at 10,8 knots.

Slow down the boat

With the expected strong winds, Lionel’s main problem is to slow down the boat, since it is impossible to lower the main sail. This sail is hooked at the second reef point, and obviously he cannot use the halyards (ropes) which are usually used to manoeuvre it. As an experienced sailor, after having discussed the matter over with Olivier Wroczynski, the trimaran’s boat master, he decided to let the ropes drag behind the boat, in order to keep the speed below 20 knots (37 km/h). He should thus reach the French coastline by daylight. Two assistance boats with 4 members of the Gitana Team each are in stand-by, ready to leave and meet Gitana X, in order to help Lionel reach his mooring.

Team Spirit

“We’re obviously very disappointed for Lionel and the whole Gitana Team. This incident is a tough one. But that’s the way it goes in mechanical sports“, immediately declared Benjamin de Rotschild, the ship’s owner and crew member, and Olivier Besse, project manager, when they heard the news. They also congratulated Lionel for his careful race debut aboard a brand new trimaran, which had only sailed 2000 miles (3700 km) prior to the Route du Rhum start.

Estimated Time of Arrival (ETA) : between 06:00 and 08:00 French time (05:00 and 06:00 GMT) off Belle Isle, 20 miles (37 km) away from La Trinité-sur-Mer.

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