True Radial -- Racing Spinnakers

While differences in spinnaker moulds may not be immediately apparent to the untrained eye, North sail designers refine proven molds/shapes to match the distribution of area, girths and profile to each particular class or yacht. New designs are optimized with North's exclusive FLOW and MEMBRANE computer simulation programs, which analyze pressure and stresses on the sail at various wind speeds and angles. With this data, the designer can create a "flying shape" that more accurately matches the designed shape. The result is a spinnaker that is fast and easy­to­fly.


For the 1995 America's Cup, North Sails New Zealand developed a unique "twisted wind tunnel" to better replicate the differences in wind speed and angle a spinnaker experiences between deck level and the upper part of the rig. The tunnel, developed in conjunction with the University of Auckland, has allowed North sail designers to harness more speed over a broader wind spectrum for a specific spinnaker design.

The ongoing development of fast shapes will continue ­ especially with the upcoming Whitbread Round the World Race; a true test of speed and durability.

Spinnaker Cloth Options

North TRUE RADIAL spinnakers are available in two lightweight cloth types, polyester and nylon. Each has its advantages. For instance, polyesters stretch less for their weight, especially when wet, but cannot withstand "shock­loading" as well as nylon. Conversely, nylon loses as much as half of its strength when wet, but is a better choice for rough water, or offshore racing. Polyesters tend to last longer than nylon styles but are not as resistant to tearing. Following is a table of available cloth weights and colors for the complete range of TRUE RADIAL spinnaker designs.

NorLon™ .75 and 1.5 oz. White, Red, Green, Yellow, Lt. Blue, Dark Blue, Purple, Black, Caribbean, Fuschia, Mango, Grape, Raspberry


NorLon Accent Colors (.75 only) Periwinkle, Sweet Pea, Pumpkin, Yam, Beige* (Great for inlays, faces,and flesh tones)

NorLon 250 Colors White,Red, Blue

.6 Nylon (30/20) White,Red, Blue

.5 Contender SuperLite White,Red, Blue

.5 Polyester White, Red, Yellow, Dark Blue, Gray

.6 Polyester White, Red, Dark Blue, Light Blue, Yellow, Green, Purple, Gray, Hot Yellow, Hot Green, Hot Orange, Hot Pink

.85 Polyester White, Red, Dark Blue, Yellow, Green, Hot Pink

Specifications subject to change and may vary from loft to loft. 1997 North Sails. All rights reserved True Radial and NorLon are trademarks of North Sails.