TECHNICAL UPDATES FROM THE WORLDS, SEMI RADIAL OR CROSSCUT?

 Whats the difference between the two models? And how should you choose the right sail for your sailing style and conditions?

CD SAILS TECHNICAL UPDATES FROM THE WORLDS, SEMIRADIAL OR CROSSCUT? THE PAPPAS AND LUBIANSKA CASE. 

 

During the last World Championship, held in Portorož, Slovenia, our sail models delivered an outstanding performance. Lighter sailors were flying with the Medium model, while heavier sailors held their pace with the DRS++.

One of the most frequently asked questions we receive is: How do you choose between a crosscut and a semiradial sail model?

In this article, Id like to present two different case studies. On one hand, we have Nikos Pappas, who won the overall title using the CD Medium model. On the other, Olha Lubianska, sailing with the DRS Classic, finished 5th overall and claimed the female world champion title.

Both sailors weighed under 40 kg and had the opportunity to test both semiradial and crosscut models.

So, whats the difference between the two models? And how should you choose the right sail for your sailing style and conditions?

Which are the  advantages of a Semiradial Cut? 

When comparing the two different cuts, the main distinguishing factor is shape stability. A semiradial model distributes tension along the direction of load, which is made possible by the orientation of the sail panels. This results in a structure that better resists deformation, especially under higher loads or in gusty conditions.

Pict. 1. Ripstop tissue, Warp fibres horizontally and Fill fibres vertically providing stretch resistance.

Pict.2 DRS classic, visual explanation of the direction of the panels in a semiradial cut vs a crosscut

By observing Picture 1, we can see that the warp and fill directions of the sailcloth help prevent deformation, while the diagonal axis is more susceptible to shape changes due to the tension transmitted by the wind through the spars.

Less deformation of the sailcloth ensures a more stable shape during navigation. Whether a sail is designed to be stable or not ultimately depends on the sailmakers intent.

The design of the sail determines the cut and influences how the material behaves while sailing.

This is the result of a complex process involving numerous tests and adjustments.

Why dont we develop full radial sails?

 This ties into the previous topic. While its possible to produce full radial sails, they do not perform in the same way as DRS sails. The performance of the DRS comes from a well-considered combination of radial and crosscut sections, along with precise shaping and careful adjustment of tension along the luff and leech. Given how effectively the DRS performs, theres currently no need to change it.

Which are the advantages of a cross-cut model?

A clean crosscut design is easy to rig and tune. Sailors can easily identify how to adjust the sail to achieve the desired shape. Our crosscut models delivered outstanding results in 2025, winning several national championships, the Female Overall Europeans, and the Overall World Championship. These sails are all-around, user-friendly, modern in both shape and design, and deliver excellent performance on the water.

Whats the next step in developing Optimist performance?

CD Sails has developed a new line of masts, specifically designed to complement our sails. These masts are lighter than most currently on the market and come with varied stiffness options. Every time a disruptive product enters the market, it opens up new possibilities for performance gains through different gear combinations. Now is the time to experiment with different spar setups and CD sail models to gain a competitive edge.

 

Different Applications of the DRS Model According to Sailor Weight and Gear

Over the past six months, we have tested the DRS in a variety of conditions, with different gear setups and a wide range of sailor weights. After extensive testing and gathering direct feedback from coaches and athletes, Claudio Demartis decided to introduce two new versions of the semi-radial model: the DRS- and the DRS++.

After extensive testing and gathering direct feedback from coaches and athletes, Claudio Demartis decided to introduce two new versions of the semi-radial model: the DRS- and the DRS++.

Each of the three models (DRS-, DRS, and DRS++) features a distinct design. These are not just flatter or more powerful versions of the standard DRS — they are tailored for different sailor profiles and conditions. Each model is best suited for a specific weight range, which can be slightly adjusted by fine-tuning the type of spars used.

Choosing the Right Model Based on Sailor Weight

The primary factor in selecting the appropriate DRS model is the sailors weight. Once this parameter is clear, you can then fine-tune your setup with appropriate gear.

Recommended weight ranges for each model:

DRS-: 34–38 kg

DRS: 38–45 kg

DRS++: Over 46 kg

These recommendations provide a starting point for approaching the CD Sails DRS range. Below is a guide to pairing each model with the appropriate spars.

How to Choose Spars for Each DRS Model

DRS- (34–38 kg)

Positioned between the Flat and Medium models, the DRS- is ideal for sailors who can handle a more technical sail shape and who feel underpowered with the CD Flat in light conditions.

This model is best used with softer spars. Start with the gear the sailor typically uses, then progressively test stiffer or softer combinations.

Recommended setup:

Mast: MK3, MK3 Medium, MK3 Flex, CD Soft

Boom: 45 mm

Sprit: MK3 Flex, MK3 HF

Progression Tip:

After using the DRS-, sailors may transition to the CD Medium. Alternatively, they can move to the DRS model while retaining soft spars, gaining more speed in light-to-medium winds, though possibly sacrificing performance in stronger wind.

DRS (38–45 kg)

Previously described as a sail best paired with stiff spars, the DRS remains highly effective in that configuration. However, feedback from high-level, lighter sailors over recent months has shown success using the DRS with softer spars as well.

If a sailor is at the lighter end of the range, softer spars can enhance performance in light and medium winds while still offering control in heavier conditions. Conversely, heavier sailors within the range should opt for stiffer setups for better power handling.

Recommended setups:

Lighter sailors (38–41 kg):

Mast: MK3 Flex, CD Soft

Boom: 45 mm

Sprit: MK3 HF

Heavier sailors (42–45 kg):

Mast: MK3, MK4, CD Medium, CD Hard

Boom: 45 mm or 48 mm

Sprit: MK3 Flex, MK3

Tuning Advice:

Adjust the stiffness of your gear according to your position within the weight range. Lighter sailors benefit from extra power and flexibility, while heavier sailors need stability and control.

DRS++ (46+ kg)

Designed for sailors who are comfortable with the DRS but have outgrown its optimal weight range, the DRS++ offers more power while retaining the signature fine-tuning, angle, and acceleration characteristics of the DRS.

This model has proven successful in recent national trials, helping many sailors achieve top results.

Recommended setup:

Mast: MK3, MK4, CD Medium, CD Hard

Boom: 45 mm or 48 mm

Sprit: MK3 HF

Performance Tip:

This model is ideal for heavier sailors seeking an extra performance edge without sacrificing handling or responsiveness.

 

 

by Santiago Lopez

 

CD Sails sail and mast models scheme: