The invention relates to a fabric for lightweight nautical sails, such as spinnakers, asymmetric spinnakers, and gennakers, for sailboats and other surface vessels, the fabric being formed of continuous polyester warp and weft yarns and being coated on one or both of its two surfaces with a crosslinked polymer, characterised in that the polyester is poly(ethylene terephthalate) (PET) having a tenacity greater than or equal to 6 cN/dtex; in that the fabric has a density of between 20 and 50 threads/cm, in terms of warp and weft density; in that the polymer is a crosslinked polyurethane (PU) that is polyether-, polyester-, or polycarbonate based; and in that this PU is derived from the crosslinking (1) of a single-component polyurethane elastomer having a modulus at 100% elongation comprised between 1 and 15 MPa, better still between 2 and 15 MPa, in particular between 6 and 15 MPa, according to the standard DIN 53504, used in implementation in solvent phase; and (2) by a crosslinking agent, based on a proportion of dry crosslinking agent relative to the dry elastomer of between 20% and 75% by weight, in particular between approximately 30% and approximately 75% by weight. The coated fabric has an elongation in the bias direction under 20 Lbs, comprised between 10 and 30 hundredths of an inch.

The invention relates to a fabric for lightweight nautical sails, such as spinnakers, asymmetric spinnakers, and gennakers, for sailboats and other surface vessels, the fabric being formed of continuous polyester warp and weft yarns and being coated on one or both of its two surfaces with a crosslinked polymer, characterised in that the polyester is poly(ethylene terephthalate) (PET) having a tenacity greater than or equal to 6 cN/dtex; in that the fabric has a density of between 20 and 50 threads/cm, in terms of warp and weft density; in that the polymer is a crosslinked polyurethane (PU) that is polyether-, polyester-, or polycarbonate based; and in that this PU is derived from the crosslinking (1) of a single-component polyurethane elastomer having a modulus at 100% elongation comprised between 1 and 15 MPa, better still between 2 and 15 MPa, in particular between 6 and 15 MPa, according to the standard DIN 53504, used in implementation in solvent phase; and (2) by a crosslinking agent, based on a proportion of dry crosslinking agent relative to the dry elastomer of between 20% and 75% by weight, in particular between approximately 30% and approximately 75% by weight. The coated fabric has an elongation in the bias direction under 20 Lbs, comprised between 10 and 30 hundredths of an inch.

Disclosed is a sail comprising a head, a tack, and a luff extending between the head and the tack; a luff region extending along the luff; wherein the luff region has a significantly higher degree of elasticity compared to the average elasticity of a remainder of the sail. Also disclosed is a method of making a sail comprising laying out material to form the sail; arranging material in a luff region of the sail and in the remainder of the sail such that in the direction of the luff, the luff region has a higher degree of elasticity compared to the remainder of the sail; curing or sewing the sail to form a cohesive structure.

Disclosed is a sail comprising a head, a tack, and a luff extending between the head and the tack; a luff region extending along the luff; wherein the luff region has a significantly higher degree of elasticity compared to the average elasticity of a remainder of the sail. Also disclosed is a method of making a sail comprising laying out material to form the sail; arranging material in a luff region of the sail and in the remainder of the sail such that in the direction of the luff, the luff region has a higher degree of elasticity compared to the remainder of the sail; curing or sewing the sail to form a cohesive structure.

A multi-layer bladder construct consisting of a non-stretchable outer covering and a stretchable inner bladder. The outer covering has an inner surface and is made from woven polymer fibers having a warp direction and a weft direction. The inner bladder is made from a bi-axially oriented polymer film. The inner bladder has an outer surface area that is smaller than the inner surface area of the outer covering. Upon inflation, the inner bladder stretches and expands until the outer surface of the inner bladder engages the inner surface of the outer covering, whereby a portion of tensile force loading on the outer covering is shared with the inner bladder. A stretchable flexible film is incorporated into the inner bladder in at least one selected location. The stretchable flexible film has an elastic expansion range which is greater that the elastic expansion range of the remainder of the inner bladder.

A laminate (1) delimited by at least a protective skin (30) and provided internally with reinforcing means (10) comprising a plurality of traction members (12, 20) arranged according to lines (L) traced in a given manner; at least one plastic matrix (M) shaped so as to stably embody each traction member (12, 20) to maintain it, under load, stably arranged point to point just as the corresponding line (L).

A laminate (1) delimited by at least a protective skin (30) and provided internally with reinforcing means (10) comprising a plurality of traction members (12, 20) arranged according to lines (L) traced in a given manner; at least one plastic matrix (M) shaped so as to stably embody each traction member (12, 20) to maintain it, under load, stably arranged point to point just as the corresponding line (L).

A mast fairing for a sailboat includes an upper fairing and an optional lower fairing configured to reduce turbulent airflow over the upwind and downwind sides of a sail. The upper fairing includes a fairing wrap includes a central segment configured to wrap around a mast, a left-side panel, a right-side panel, and a sail track attached to trailing edges of the left- and right-side panels. One or more fairing supports are optionally attached to the sail track between the left- and right-side panels of the fairing wrap. The optional lower fairing includes a central segment, a left-side panel, and a right-side panel configured for installation on a mast and boom below the upper fairing. The upper and lower fairings reduce turbulent airflow over the surfaces of a sail and increase regions of laminar airflow to improve the performance of the sail.

A mast fairing for a sailboat includes an upper fairing and an optional lower fairing configured to reduce turbulent airflow over the upwind and downwind sides of a sail. The upper fairing includes a fairing wrap includes a central segment configured to wrap around a mast, a left-side panel, a right-side panel, and a sail track attached to trailing edges of the left- and right-side panels. One or more fairing supports are optionally attached to the sail track between the left- and right-side panels of the fairing wrap. The optional lower fairing includes a central segment, a left-side panel, and a right-side panel configured for installation on a mast and boom below the upper fairing. The upper and lower fairings reduce turbulent airflow over the surfaces of a sail and increase regions of laminar airflow to improve the performance of the sail.

Propulsion apparatus for an aquatic vessel comprises an aerodynamic body which extends along a longitudinal axis between first and second ends and in a transverse direction between a leading edge and trailing edge. The aerodynamic body has one or more external wind-receiving surfaces which extend between the leading edge and the trailing edge, thereby defining an aerodynamic profile of the aerodynamic body in cross-section substantially perpendicular to the longitudinal axis. The propulsion apparatus further comprises at least one air vent and at least one air flow generator configured to expel air through the at least one air vent. The at least one air vent and/or the at least one air flow generator are configured to direct expelled air across at least a portion of the one or more or more external wind-receiving surfaces.