The ideal sailcloth fiber would:

But in the real world, available fibers exhibit varying degrees of these attributes with some materials having vanishingly small levels of stretch for weight, but less than desirable durability, while others are tough, but somewhat stretchy. Finding the right balance of properties for your type of sailing and keeping within budget is the key to being happy with your sails.

3Di technology is made possible because of three components:

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OLD but good explanation

A New Class Of Superyacht Cruising Sails 3Di OCEAN is engineered to meet the expectations of large global cruising yachts. OCEAN features the highest UltraPE ‘Dyneema’ content of any 3Di product, maximizing the benefits of UltraPE material properties in spread filament, molded composite sailmaking. 3Di OCEAN sails provide ease of use and handling by reducing bulk, weight and stiffness while retaining ultimate breaking strength and reliability. 3Di OCEAN employs protective outer surfaces of woven polyester taffeta tapes that are tougher and more durable than non-woven ‘skins’. This surface provides additional protection against flex, chafe, abrasion and UV degradation. Available in a choice of surface colors, 3Di OCEAN sails provide the striking appearance and performance of 3Di, with a focus on long term durability and value.

3Di ENDURANCE is the most rugged version of our composite molded sail technology. ENDURANCE sails strike a balance between performance and reliability. Evolved from the original 3Di sail and continually refined, 3Di ENDURANCE represents the state of the art in high performance and durability.

In addition to the unique benefits inherent to all 3Di sails, the defining characteristic of ENDURANCE is a special group of external non-woven filament tapes that carry a tough, proprietary, surface resin. ENDURANCE offers enhanced protection against damage from flex, abrasion and UV exposure. For many sailors, this added durability is a worthwhile benefit despite a modest increase in sail weight and thickness compared to RAW sails.

Coastal Cruising / Offshore Cruising / Inshore Racing / Offshore Racing / Multihull

Square Top Mainsails, our most advanced model, dominate Grand Prix racing worldwide. The square top profile provides highly efficient progressive twist, reduced mast tip vortex and optimized sail area distribution. North designers precisely balance sail camber with head width while accounting for specific mast bend characteristics and target sailing conditions. All sail elements work together, including membrane modulus, batten stiffness, and batten configuration – resulting in finely controlled airfoil performance.

Roller Furling Genoas are the primary workhorse on most cruising boats. North Furling Genoas have the strength and toughness to withstand the inevitable flogging, furling, rig impact and shock loading associated with bluewater sailing. We offer a dedicated range of cruising materials designed to endure harsh conditions.

Our specialized cruising designs provide smoother shape on all points of sail – whether beating, reaching, or running wing on wing. To ensure many years or cruising performance and value, North Sails cruising experts customize your genoa to fit your needs.

For the first time, sailors can enjoy the benefits of 3D molding and composite construction in select downwind sails.

3D molding provides a precisely shaped and smooth sail surface for optimized aerodynamics. Composite construction enables high-resolution spread filament tape distribution, placing exactly the right amount of material in exactly the right direction.

3Di Downwind eliminates the parasitic weight and inevitable distortion of mylar film – a significant advantage in lightweight downwind sails.

Offshore Racing / Course Record Breaking / Multihull Racing and Cruising

Helix Code Sails are designed for ultimate versatility and steady power delivery. This new generation of Code Sails features a Structured Luff that optimally shares the overall load with a purpose-built Future Fibres cord; enabling steady power delivery, lower the total load, greater luff projection, and a wider range. The performance potential of Helix Code Sails is maximized with North 3Di but is also available for downwind paneled sails.

More about Helix

North’s powerful Racing Asymmetrics are the evolutionary descendants of our dominant America’s Cup and Volvo Ocean Race designs. They have been developed using the University of Auckland Twisted Flow Wind Tunnel and the North Sails Virtual Wind Tunnel™ downwind flow simulation software.

The result is a stable asymmetric spinnaker that delivers increased drive and reduced drag over a broader wind spectrum, which is especially important for today’s generation of lighter, faster-accelerating boats.

North Racing Asymmetrics are offered in six different wind range models, each with a targeted selection of high performance downwind materials to precisely match your boat and type of racing.

WIND ANGLE CHART