Hang glider sailcloth

There are basically two types of sail materials used in hang glider sails Woven Polyester Fabrics, and Composite Laminated Fabrics made of some combination of polyester film and polyester fibers.Woven polyester sailcloth is a very tight weave of small diameter polyester fibers that has been stabilized by the hot press impregnation of a polyester resin. The resin impregnation is required to provide resistance to distortion and stretch. This resistance is important in maintaining the aerodynamic shape of the sail. Woven polyester provides the best combination of light weight and durability in a sail with the best overall handling qualities.

Laminated sail materials using polyester film achieve superior performance by using a lower stretch material that is better at maintaining sail shape but is still relatively light in weight. The disadvantages of polyester film fabrics is that the reduced elasticity under load generally results in stiffer and less responsive handling, and polyester laminated fabrics are generally not as durable or long lasting as the woven fabrics.