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.

09.06.2004

Damaged dagger board for Fred Le Peutrec.

As Yann Marilley , Gitana Team Manager was getting ready to hop on board a plane for at 14h this afternoon, he received a telephone call from Fred Le Peutrec, skipper of Gitana 11, informing him that he has struck non-identified object yesterday evening.

par Gitana

Lying 700 miles from the finish at the time, Fred was sailing downwind, dagger board raised, which minimised the damage to what is a vital appendage for upwind sailing. Fred waited until the daylight hours before checking the board and calling the Gitana Team to discuss necessary repairs before the boat sets out on her delivery passage for Québec on 20th June. The dagger board’s crash box (which acts as a fuse in the event of an impact) has broken, the lesser of two evils compared to what happened to Marc Guillemot on Gitana X, whose lowered dagger board snapped clean away on a level with the underside part of the hull. Yann Marilley and Jean Le Houérou Kérisel will have to wait until Gitana 11 gets in before being in a position to fine tune the early diagnosis and set about making the necessary repairs with the shore crew.For the time being, the end of the race is going to be difficult for Fred who is now without his Solent and for whom the efficiency of the dagger board is severely reduced, all the more so given that part of the course remaining to be covered has to be sailed upwind.

Originally expected in Thursday night – Friday morning, his technical crew have now pushed the ETA back a few hours.

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