Patent ID: 6925950

Claim:
A composite iso-stress sail structure comprising: a sail body, placeable in a chosen sail shape, comprising: a plurality of expected iso-stress lines, said iso-stress lines determined when the sail shape is under at least one loading within a chosen range of loadings; a corner; first and second edges extending from the corner, said first and second edges having first and second lengths; and a sail body material and a plurality of iso-stress elements laminated to the sail body material to create an iso-stress portion extending from the corner along the first and second edges for first and second distances; at least some of said plurality of iso-stress elements being layered one on top of one other; the iso-stress elements comprising a plurality of edges shaped to be at least generally parallel to corresponding ones of said iso-stress lines; and at least one of said first and second distances being greater than 20% of the first and second lengths, respectively.