Abrégé

The present invention is a Low-Drag Fin and Foil System for Surfboards (10), particularly including cambered fin foils (40; 42). The invention (10) also discloses low-drag, directionally unstable fin positions wherein the lesser of negative angle of attack of a trailing fin (50), versus the higher or positive angle of attack of a forward fin (48), makes the board (12) highly maneuverable by creating a yawing moment that aids the rotation of the board (12) as it is turned. The system particularly utilizes fins (40) having foil (42) shapes in which either the cambered side (74) or the non-cambered side (76) is provided with a combination of a convex curvature (68) and a concave curvature (70) to result in an oscillating curvature (72) which has a positive effect on control and acceleration.

Classes IPC  ?

• B63B 32/60 - Appendices de planches, p. ex. ailerons, ailes portantes ou dérives centrales
• B63B 32/00 - Planches de sports nautiquesAccessoires à cet effet
• B63B 39/06 - Installations pour diminuer le tangage, le roulis ou autres mouvements similaires indésirables du navireAppareils pour indiquer l'assiette du navire réduisant les mouvements du navire par l'effet d'ailerons agissant sur l'eau ambiante
• B63B 32/50 - Planches caractérisées par leurs particularités de construction

Abrégé

The present invention is a Low-Drag Fin and Foil System for Surfboards (10), particularly including cambered fin foils (40; 42). The invention (10) also discloses low-drag, directionally unstable fin positions wherein the lesser of negative angle of attack of a trailing fin (50), versus the higher or positive angle of attack of a forward fin (48), makes the board (12) highly maneuverable by creating a yawing moment that aids the rotation of the board (12) as it is turned. The system particularly utilizes fins (40) having foil (42) shapes in which either the cambered side (74) or the non-cambered side (76) is provided with a combination of a convex curvature (68) and a concave curvature (70) to result in an oscillating curvature (72) which has a positive effect on control and acceleration.

Classes IPC  ?

• B63B 35/79 - Planches de glisse, p.ex. planches à voile 
• B63B 39/06 - Installations pour diminuer le tangage, le roulis ou autres mouvements similaires indésirables du navireAppareils pour indiquer l'assiette du navire réduisant les mouvements du navire par l'effet d'ailerons agissant sur l'eau ambiante

Abrégé

The present invention is a Low-Drag Fin and Foil System for Surfboards (10), particularly including cambered fin foils (40; 42). The invention (10) also discloses low-drag, directionally unstable fin positions wherein the lesser of negative angle of attack of a trailing fin (50), versus the higher or positive angle of attack of a forward fin (48), makes the board (12) highly maneuverable by creating a yawing moment that aids the rotation of the board (12) as it is turned. The system particularly utilizes fins (40) having foil (42) shapes in which either the cambered side (74) or the non-cambered side (76) is provided with a combination of a convex curvature (68) and a concave curvature (70) to result in an oscillating curvature (72) which has a positive effect on control and acceleration.

Classes IPC  ?

• B63B 35/79 - Planches de glisse, p.ex. planches à voile 
• B63B 39/06 - Installations pour diminuer le tangage, le roulis ou autres mouvements similaires indésirables du navireAppareils pour indiquer l'assiette du navire réduisant les mouvements du navire par l'effet d'ailerons agissant sur l'eau ambiante
• B63B 41/00 - Quilles rétractables, p. ex. de dérive centrale ou latérale

Abrégé

The present invention is a Low-Drag Fin and Foil System for Surfboards (10), particularly including cambered fin foils (40; 42). The invention (10) also discloses low-drag, directionally unstable fin positions wherein the lesser of negative angle of attack of a trailing fin (50), versus the higher or positive angle of attack of a forward fin (48), makes the board (12) highly maneuverable by creating a yawing moment that aids the rotation of the board (12) as it is turned. The system particularly utilizes fins (40) having foil (42) shapes in which either the cambered side (74) or the non-cambered side (76) is provided with a combination of a convex curvature (68) and a concave curvature (70) to result in an oscillating curvature (72) which has a positive effect on control and acceleration.

Classes IPC  ?

• B63B 35/79 - Planches de glisse, p.ex. planches à voile 
• B63B 39/06 - Installations pour diminuer le tangage, le roulis ou autres mouvements similaires indésirables du navireAppareils pour indiquer l'assiette du navire réduisant les mouvements du navire par l'effet d'ailerons agissant sur l'eau ambiante
• B63B 41/00 - Quilles rétractables, p. ex. de dérive centrale ou latérale

Abrégé

The present invention is a Low-Drag Fin and Foil System for Surfboards (10), particularly including cambered fin foils (40; 42). The invention (10) also discloses low-drag, directionally unstable fin positions wherein the lesser of negative angle of attack of a trailing fin (50), versus the higher or positive angle of attack of a forward fin (48), makes the board (12) highly maneuverable by creating a yawing moment that aids the rotation of the board (12) as it is turned. The system particularly utilizes fins (40) having foil (42) shapes in which either the cambered side (74) or the non-cambered side (76) is provided with a combination of a convex curvature (68) and a concave curvature (70) to result in an oscillating curvature (72) which has a positive effect on control and acceleration.

Classes IPC  ?

• B63B 35/79 - Planches de glisse, p.ex. planches à voile 
• B63B 39/06 - Installations pour diminuer le tangage, le roulis ou autres mouvements similaires indésirables du navireAppareils pour indiquer l'assiette du navire réduisant les mouvements du navire par l'effet d'ailerons agissant sur l'eau ambiante
• B63B 41/00 - Quilles rétractables, p. ex. de dérive centrale ou latérale