North Sails has designed the sails for three-quarters of the Vendée Globe IMOCA fleet, 17 of which have a full set and 7 with a partial set.
Each boat has a distinctive set of sails depending on several parameters such as the shape of the hull, the deck plan, the rigging, or even a new element today: the foils whose air behavior plays a critical role in the stability of the boat.
This wardrobe must also cover all the wind conditions encountered during competition.
Defining the right sail inventory can be complex. Yann Regniau, Yann Andrillon, and Quentin Ponroy, designers at North Sails France, enlighten us on the design of the sails of a singular boat, the IMOCA for an equally singular race: the Vendée Globe.
How do you design a set of sails for a Vendée Globe?
There are no absolute rules. It depends on the team, whether they are building a new boat or not, and on the expertise they have in-house.
In summary, the sail design is fed by three means: theoretical studies from North Sails (aero and structure), a rich database of sails designed for IMOCA boats combined with our expertise and boat-skipper input.
The main stages include the definition of the specifications of the sail with the team – the design (theoretical studies, 3D drawing, and structure).
The manufacturing sheet – the manufacturing of the 3Di structure in Minden (Nevada, USA) and finally the finishes at North Sails France (Vannes, Brittany).
Within North, we have a software solution for designing, studying, and dimensioning the structure of 3Di sails, the North Design Suite, which includes among others Spiral for the sail design, Desman to model the rigging in 3D and Membrain to generate deformed sails. We also use Rhinoceros for the architect’s plans.
What are the main trends in terms of sails since the last Vendée Globe?
The sails have less volume on the upper part and the volumes are further forward. The most visible point is the reduction in head width and the roach of the leech of our mainsails are “S” shaped.
Without forgetting that most of the headsails are load sharing, using the North Sails Helix structure luff.
Can you name the eight sails for this Vendée and what they are used for?
– A Mainsail
– An obligatory storm Jib 20 m2 minimum
– J3: Heavy air upwind sail/gennaker staysail off the wind
– J2: Upwind and close-reaching sail used from 12 knots upwards
– FRO: upwind sailing in light airs and reaching all the way to downwind in heavy air
– J0: Masthead Gennaker (190 m2 flat sail) for light airs and reaching
– A7: Fractional reaching and downwind reaching Gennaker in strong winds
– A3: large Gennaker of around 300 m2 for downwind sailing up to 25 knots
The next edition of the Vendée Globe race is set to start from Les Sables d’Olonne, 8 November 2020.
Vendée Globe race website here . . .