Symmetrical Spinnakers: S3 Medium Air Reaching
AWS 10-20 kts
Mid Girth 85-95% of foot length
Flat for reaching and reduced shoulders
Medium to heavy cloth to offset heeling loads
Reaching spinnakers are flatter than running chutes to reduce heeling at tighter wind angles. While an S3 has the same area as an S1, the material on the S3 is heavier in order to stand up to the greater loads from higher winds. While an S1 would be made out of .5 oz or .6 oz. nylon, an S3 is be made out of .75 oz. to .9 oz. cloth.
The heart of faster spinnakers is the construction method. The panel layout UK Sailmakers uses is called Matrix, which is a full radial layout that features narrow panels, each oriented to better align the threads in the cloth with the primary load-paths in the spinnaker. This is the most effective way to reduce distortion and make the strongest sail for its weight.
Each panel is shaped on all four sides in order to create a smooth round sail. For one sail to be so versatile, it needs to hold its shape without distorting. Distortion becomes most obvious when close reaching. Spinnakers made with generic nylon cloth stretch in the middle, causing their leeches to harden or hook; which reduces driving power, creates drag, and increases heeling. The only way to prevent distortion, without using too heavy a fabric, is to use performance nylon spinnaker cloth like those made under the Superkote and Airx names. These materials have the same strength and stretch resistance of one weight heavier standard nylon.
Spinnaker Painting Program
Use this program to create a custom look for your new spinnaker or cruising spinnaker. Click here to go to the Spinnaker Painting Program.