A closer look at two Ultims, winners of
the Jules Verne Trophy
Idec Sport (2006) & Sodebo Ultim’3 (2019)
Two yachts that circumnavigated the globe in 40 days! That warranted an architectural analysis. One of them “flies,” the other doesn’t. Actually, their designs didn’t have the same goals. This comparison highlights 20 years of progress.
Idec Sport
Launched in 2006, Idec Sport betrays her age, with a fairly central mast, high bows, and basic lines. Originally known as Groupama 3, she was rechristened Maxi Solo Banque Populaire VII in 2013, before taking on her current name, Idec Sport, in 2015. She has twice won the Jules Verne Trophy, in 2010 and 2017, and has triumphed four times on the Route du Rhum. Sailing under the flag of The Famous Project, she has just set a new benchmark for an all-female crew, led by Alexia Barrier.
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| © F. Chevalier |
Idec Sport
Maximum overall length: 31.50 m
Maximum beam: 22.5 m
Mast height: 120% of the maximum length.
Maximum beam: 22.5 m
Mast height: 120% of the maximum length.
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| © F. Chevalier |
Sodebo Ultim’3
The innovative feature of the Sodebo Ultim’3 lies in the position of the living quarters forward of the mast.
This results in a more centered weight distribution, as opposed to a roof placed ahead of the aft beam. A mast seated well back, beyond section 6, offsets the balance. The Sodebo’s mast is the rearmost of the entire Ultim fleet. The advantage of freeing up the area under the mainsail allows for the creation of a transom at the stern, like America’s Cup yachts. Since her launch in 2019, extensive work on weight reduction, aerodynamics, and foils has improved the performance and flight characteristics of this Ultim.
This results in a more centered weight distribution, as opposed to a roof placed ahead of the aft beam. A mast seated well back, beyond section 6, offsets the balance. The Sodebo’s mast is the rearmost of the entire Ultim fleet. The advantage of freeing up the area under the mainsail allows for the creation of a transom at the stern, like America’s Cup yachts. Since her launch in 2019, extensive work on weight reduction, aerodynamics, and foils has improved the performance and flight characteristics of this Ultim.
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| © F. Chevalier |
Sodebo Ultim’3
Maximum overall length: 32 m
Maximum beam: 23 m
Mast height: 120% of the maximum length.
Maximum overall length: 32 m
Maximum beam: 23 m
Mast height: 120% of the maximum length.
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| © F. Chevalier |
Idec Sport central hull
The central hull features a V-shape that broadens from bow to stern, with oval-shaped bottoms at the bow that round out to the center and flatten toward the stern.
Unlike the more modern Ultim models, the hull remains wide all the way to the stern. The deepest point emerges at the center of the centerboard, but the volume above it increases toward the stern.
Unlike the more modern Ultim models, the hull remains wide all the way to the stern. The deepest point emerges at the center of the centerboard, but the volume above it increases toward the stern.
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| © F. Chevalier |
Sodebo Ultim’3 central hull
Like her side floats, the main hull includes an inverted bow designed as a wave-piercing bow. This minimizes deceleration in head-on swells or when coming down from planning.
The hull features highly tulip-shaped sections, contributing to a slender waterline and ample buoyancy in the upper sections. The hull is rounded throughout the front and gradually flattens out from the centerboard. Despite its age, the hull still offers impressive speed potential compared to recent Ultim models.
The hull features highly tulip-shaped sections, contributing to a slender waterline and ample buoyancy in the upper sections. The hull is rounded throughout the front and gradually flattens out from the centerboard. Despite its age, the hull still offers impressive speed potential compared to recent Ultim models.
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| © F. Chevalier |
Idec Sport floats
The bow and sections, with their rounded shapes both on top and at the bottom, characterize the 2000s. The bow is high and slender; at the time, in 2006, inverted bows weren’t yet adopted, although the smaller Class C boats just began to use them. The curved foil, with a tab at its lower end, provides greater stiffness, allowing the sail area to be maintained without the float sinking excessively.
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| © F. Chevalier |
Sodebo Ultim’3 floats
Shortened by 3.35 m at the stern and fitted with retractable rudders for the 2021 season, these hulls have the lowest displacement of any current Ultim. Their hull sections boast a distinctive tulip shape, with a flat bottom at the bow and stern, a rounded midsection, flared sides, and a sharp-pointed deck in the forward half. With little draft, and despite narrow bottoms, they offer a relatively good buoyancy reserve. The foils have grown longer over time, and the boat now flies with great stability.
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| © F. Chevalier |
Comparison of the central hulls and float sections
A side-by-side view of the two Ultims highlights their differences in design.
Thirteen years have passed since their conception, and the designers have refined the outlines of these Ultims by reducing wind resistance at the bow and the boat’s impact when sailing in waves. The hull shapes have also evolved, as speed has become a priority.
Thirteen years have passed since their conception, and the designers have refined the outlines of these Ultims by reducing wind resistance at the bow and the boat’s impact when sailing in waves. The hull shapes have also evolved, as speed has become a priority.
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| © F. Chevalier |
