The 17 sail, to my knowledge, has gone through five iterations.

First was the original horizontal cut.

Second was the radial cut, constructed from Teijin Taffeta Mylar. Japanese Fabric, Neil Pryde, Hong Kong constructed. The mylar choice was simple, they were using it in the windsurfing sails they were building at the time. Re-inforcements along the leech to keep the sail from stretching out. The vertical luff panels were 4.0oz dacron.

Third was the same design built by Hobie Cat USA. Hand cut panels.

Fourth was the same design, contructed from Dimension/Polyant 180x, colored mylar taffeta, same fabric developed for windsufing sails, fabric from Germany, same Dacron Luff. Hand cut.

Fifth was a newer design imported from Neil Pryde in Hong Kong, design was same as used by Hobie Cat Europe. Same fabric, new mylar luff, computer cut. Effective around 1997.

Because of tight class rules there has been no change in the fabric.

And to the comment by one of the posters that the loads are less, not quite so. The 17 sail isn't much smaller than the new Tiger main.

Chip Buck
Former head sailmaker for Hobie Cat
www.pointsails.com