| 摘要 |
A surfboard having opposed side edges disposed symmetrically about a longitudinal centerline, the surfboard including a tail section, the side edges of the surfboard along said tail section defining a generally hourglass configuration with the contours of tail section side edges approximately hyperbolic curves. In one specific embodiment, the side edges of the tail section approximate the left- and right-hand branches of a hyperbola centered on an origin lying on said longitudinal centerline. According to another aspect of the invention, the surfboard includes a pair of side fins and a tail fin attached to the bottom surface of the board. The side fins are symmetrically disposed relative to the longitudinal centerline and are so oriented that the center planes of the side fins pass through the foci of the hyperbolic side edges of the tail section.
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