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.

11.07.2002

Lively delivery to Zeebrugge….

After leaving La Trinité-sur-Mer (Atlantic/France) on Monday July 8th at the end of the afternoon - heading for the Grand Prix de Zeebrugge (Belgium) - Gitana X reeled in the miles in a moderate wind. During one of the inspections programmed for this first major sailing, a crack in the trailing face of the forward starboard crossbeam fairing was di…

par Gitana

After leaving La Trinité-sur-Mer (Atlantic/France) on Monday July 8th at the end of the afternoon – heading for the Grand Prix de Zeebrugge (Belgium) – Gitana X reeled in the miles in a moderate wind. During one of the inspections programmed for this first major sailing, a crack in the trailing face of the forward starboard crossbeam fairing was discovered, and it was decided to stopover in Boulogne (North of France).

And yet all had been going well since the start, with Gitana X covering 400 miles (740 km) at an average speed of about 20 knots (37 kph). At 13.00 French time (11.00 Gmt), Olivier Besse, project manager and member of crew on board stated: “This delivery is astonishing. We spend our time slipping over the water between 25 and 28 knots (46 and 52 kph). We have even managed a peak of 32 knots (60 kph). Gitana X is really nicely balanced. We haven’t even nose-dived. Everything works perfectly“.

For the record, Gitana is on sea trials and the crew’s main task is to test everything…: operation of the appendages (foils, daggerboard, rudders), the canting of the mast, the on-board computer systems and the hydraulics.

Safety halt

But an hour after these serene comments, during a routine inspection of the boat whilst Gitana X was sailing on starboard tack (wind coming from the right), a crack on the trailing face of the starboard forward crossbeam was observed. Immediately, after speaking with the builder Multiplast, it was decided to call into Boulogne 20 nautical miles (37 km) away. On board for this sail, Jack Michal from the Gilles Ollier Design Team and a member of the Gitana Design Team which designed the boat, confirmed this wise decision.

On Wednesday, Gilles Ollier, boss of Multiplast and a team from his yard drove to Boulogne to carry out a deeper assessment of the damage. Gilles Ollier: “We used ultrasonics for the test, which enables us to make an in-depth analysis of the zone concerned. A similar approach to the one used on the boat before she was rolled out of the yard“.

After this test, repairs were decided. They were immediately started so that the trimaran can put to sea again and continue her sea trials.

Weather conditions permitting, Gitana X should be able leave Boulogne with the midnight lock tonight July 11.

Next news tomorrow Friday 12th July.

Delivery crew

Lionel Lemonchois / Skipper
Benjamin de Rothschild / Owner / Crewman
Olivier Besse / Project Manager / Crewman
Marc Guessard / Navigator
Yann Marilley / Crewman
François Denis / Crewman
Olivier Wroczynski / Crew
Jack Michal / Gitana Design Team & Multiplast / Crew

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