| 摘要 |
A fore and aft sail (10) (e.g. a headsail or mainsail) is constructed with a fore portion (18) and an aft portion (19) in such a way as to have a cross-sectional shape which can vary in response to varying wind conditions, similar to a bird's wing in nature. The sail (10) has lines of directional stability (20) in the luff area (18) extending between the head (12) and the tack (13) to provide a stable fore portion (18). The sail (10) also has lines of directional stability (21,16) which radiate from the clew (14) towards the aft edge (20) of the fore portion (18) of the sail (10). In use the aft edge (20) of this fore portion (18) becomes the collector for the majority of the stresses at the clew (14). Where the aft portion (19) is formed from woven material the aft portion (19) can be made up of a series of substantially triangular panels (19A-19E) with the lines of directional stability formed by the warp or the weft of the fabric being aligned along one long edge (21,16) of each substantially triangular panel (19A-19E). Alternatively, the lines of directional stability may be formed from strips of material (60,61), e.g. tapes or the like, superimposed on the surface of a sail (50). |
