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.

04.05.2013

Tour de Belle-Ile, no records in sight!.

par Gitana

For the sixth edition of the Tour de Belle-Ile, which is being contested today, 476 yachts will be vying for supremacy as they set off together from the bay of Quiberon. This certainly isn’t a record number in terms of participation, but it is clear that there is still a great deal of enthusiasm for this race, which is open to amateurs and professionals alike. With regard the weather, the race is set to be raced in light airs this year, so the race record currently held by Gitana 11, of 2 hours and 42 minutes, is unlikely to be challenged.

This morning the sun is shining in La Trinité-sur-Mer! For now though, the wind is yet to kick in and a light 5-knot breeze has been recorded at the start zone. As such the start that was initially scheduled for 1000 hours local time, has been put back. Aboard Gitana 11, Sébastien Josse and his seven crew are waiting for the off, hoping the thermal breeze will pick up so they can complete the long course (complete circumnavigation of the island of Belle-Ile) in some relatively normal conditions.

This morning, before casting off from the Breton port of La Trinité-sur-Mer, Charles Caudrelier – the navigator on Gitana 11 – gave the crew the following lowdown on the weather scenario: “The grib files are showing very little wind, with around 5 knots of breeze forecast, but given the glorious sunshine over the zone at the moment, we’re hoping that the thermal breeze will pick up and boost the forecast a little. The grib files are also announcing some cloud cover in the early afternoon, so we’ll have to monitor all that. To make La Teignouse (the first course marker, which marks the exit from the bay of Quiberon) we’ll very likely be punching tide, which would indicate a pretty slow start. In the event of an OCS (overshooting the start line), we don’t head back to re-cross the line, instead we cop a 1-hour time penalty.”

In the light airs forecast, the choice of sails and tactics, particularly along the South coast of Belle-Ile, will be vital. Indeed, during their reconnaissance trip yesterday, Sébastien Josse’s men were able to see at first hand how treacherous the wind shadow between the Pointe des Poulains and Kerdonis lighthouse can be.

Crew aboard Gitana 11 in the Tour de Belle-Ile 2013

Sébastien Josse (skipper)

Charles Caudrelier – Thomas Rouxel – Antoine Koch – Florent Chastel – Cyril Dardashti – Jean-Christophe Mourniac – David Boileau

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