Surfboard fin

A surfboard fin or skeg is a hydrofoil mounted at the tail of a surfboard or similar board to improve directional stability and control through foot-steering. Fins can provide lateral lift opposed to the water and stabilize the board's trajectory, allowing the surfer to control direction by varying their side-to-side weight distribution. The introduction of fins in the 1930s revolutionized surfing and board design. Surfboard fins may be arrayed in different numbers and configurations, and many different shapes, sizes, and materials are and have been made and used.

History

Historically, surfboards had no fins; some amount of control was achieved through convex hulls and the surfer dragging a foot in the water. A common problem with these early boards was "sliding ass", in which the tail would slip sideways, usually causing a wipeout. The first fixed fin was introduced by surfing pioneer Tom Blake in 1935. In Waikiki, Blake attached a 12-inch (30 cm) long, 4-inch (10 cm) deep metal keel from an abandoned speedboat to his surfboard, and was immediately impressed with the results. Around 1936, Woody Brown independently added a fixed fin to his second surfboard design in San Diego, which further popularized the feature.