Abstract: A composite iso-stress sail structure comprises a sail body having an expected iso-stress line, when in a chosen sail shape and under a loading within a chosen range of loadings. An iso-stress element is laminated to the sail body material to create an iso-stress portion at a corner of the sail body. An edge of iso-stress portion is shaped to be at least generally parallel to the iso-stress line. The iso-stress portion extends from the corner along at least one of the sides of the sail distances greater than 20% of the lengths of the sides, respectively.

Abstract: A composite iso-stress sail structure comprises a sail body having an expected iso-stress line, when in a chosen sail shape and under a loading within a chosen range of loadings. An iso-stress element is laminated to the sail body material to create an iso-stress portion at a corner of the sail body. An edge of iso-stress portion is shaped to be at least generally parallel to the iso-stress line. The iso-stress portion extends from the corner along at least one of the sides of the sail distances greater than 20% of the lengths of the sides, respectively.

Abstract: A composite iso-stress sail structure comprises a sail body having an expected iso-stress line, when in a chosen sail shape and under a loading within a chosen range of loadings. An iso-stress element is laminated to the sail body material to create an iso-stress portion at a corner of the sail body. An edge of iso-stress portion is shaped to be at least generally parallel to the iso-stress line. The iso-stress portion extends from the corner along at least one of the sides of the sail distances greater than 20% of the lengths of the sides, respectively.

Abstract: A sail body comprises sail body material with reinforcement stitching along expected load lines. Optionally, the sail body may be a molded, three-dimensional sail body. At least half of the reinforcement stitching may extend along at least half of the lengths of the expected load lines. The reinforcement stitching may also comprise a combination of stretch-resistant and controlled-stretch stitching styles, the combination of stitching styles may further comprise a length of stretch-resistant stitching followed by or preceded by a length of controlled-stretch stitching. Optionally, the sail body material may be molded to create a three-dimensional, molded sail body. The molding step may be carried out before the reinforcement stitching is applied to the sail body material.

Abstract: A low-stretch, flexible composite, made of one or several sections, particularly useful for making a sail (2), includes first and second polymer films (52, 62) with discontinuous, stretch-resistant segments (16) therebetween. The segments extend generally along the load lines (17) for the sail. The segments have lengths which are substantially shorter than corresponding lengths of the load lines within each section. The ends of the segments are laterally staggered relative to one another. Mats (20) of generally parallel mat elements can be used as the segments. The mat elements typically include discrete multifiber yarns (24, 26) and/or a fiber array (22), typically created by pneumatically laterally spreading apart the fibers of an untwisted multifiber yarn (32). A laminating assembly includes first and second flexible pressure sheets (66, 68), defining a sealable lamination interior (82) containing the material stack (64) to be laminated, housed within an enclosure (90).

Abstract: A composite iso-stress sail structure comprises a sail body having an expected iso-stress line, when in a chosen sail shape and under a loading within a chosen range of loadings. An iso-stress element is laminated to the sail body material to create an iso-stress portion at a corner of the sail body. An edge of iso-stress portion is shaped to be at least generally parallel to the iso-stress line. The iso-stress portion extends from the corner along at least one of the sides of the sail distances greater than 20% of the lengths of the sides, respectively.

Abstract: A sail body (3), which can be finished along its edges and corners to create a finished sail (2), includes a number of sail sections(46) joined along their edges (47). Each sail section includes a reinforced material (20) laminated between first and second films (32,42). The reinforced material includes sectors of reinforced material (30,31), each sector having a set of generally parallel reinforcement elements (24), such as fibers. The sectors of reinforced material are preferably elongate sectors in which at least the majority of the sectors have lengths (34) at least five times as long their widths (36). The sectors are arranged in an overlapping pattern and so that the set of reinforcement elements are generally aligned with the expected load lines (28)for that section of the sail body. Sections can be made of different shapes but are typically triangular or quadrilateral. The reinforce material is typically a mesh or scrim containing sets of parallel, transversely oriented fibers (24,26).

Abstract: A low-stretch, flexible composite, made of one or several sections, particularly useful for making a sail (2), includes first and second polymer films (52, 62) with discontinuous, stretch-resistant segments (16) therebetween. The segments extend generally along the load lines (17) for the sail. The segments have lengths which are substantially shorter than corresponding lengths of the load lines within each section. The ends of the segments are laterally staggered relative to one another. Mats (20) of generally parallel mat elements can be used as the segments. The mat elements typically include discrete multifiber yarns (24, 26) and/or a fiber array (22), typically created by pneumatically laterally spreading apart the fibers of an untwisted multifiber yarn (32). A laminating assembly includes first and second flexible pressure sheets (66, 68), defining a sealable lamination interior (82) containing the material stack (64) to be laminated, housed within an enclosure (90).

Abstract: A low-stretch, flexible composite, made of one or several sections, particularly useful for making a sail (2), includes first and second polymer films (52, 62) with discontinuous, stretch-resistant segments (16) therebetween. The segments extend generally along the load lines (17) for the sail. The segments have lengths which are substantially shorter than corresponding lengths of the load lines within each section. The ends of the segments are laterally staggered relative to one another. Mats (20) of generally parallel mat elements can be used as the segments. The mat elements typically include discrete multifiber yarns (24, 26) and/or a fiber array (22), typically created by pneumatically laterally spreading apart the fibers of an untwisted multifiber yarn (32). A laminating assembly includes first and second flexible pressure sheets (66, 68), defining a sealable lamination interior (82) containing the material stack (64) to be laminated, housed within an enclosure (90).

Abstract: A sail body (3) includes first and second skin layers (40, 42), each skin layer having an outer film (22) at an outer side (34) and reinforcement elements (28, 30) at an inner side (36). The skin layers are laminated with the inner sides abutting to form the sail body. The skin layers are each made up of skin components (38) joined to other skin components of the same skin layer another along their aligned edges (43). The joined edges (44) of the first skin layer are offset from the joined edges of the second skin layer to strengthen the sail body. The sail body is preferably a three-dimensional molded sail body. The fibers or other reinforcement elements are preferable generally aligned with the expected load lines (32) of the sail body.

Abstract: A one piece sail is made on a mold and includes an outer impervious layer, such as film, and an inner layer of continuous and uninterrupted yarns disposed in continuous trajectories from one edge of the sail to the other and carrying the majority of the load imposed on the sail.

Abstract: A reinforcing patch is secured to a sail to support the inner ends of battens carried in pockets on the sail. The patch is a laminate having yarns radiating in an omnidirectional pattern from the end of the batten pocket and batten.