Skegs

A skeg is a hydrofoil-like fin that projects from the hull of a watercraft, typically near the stern or along the keel. Its primary function is to improve directional stability and tracking, reducing yaw caused by wind, current, or waves. Skegs are common on a range of vessels, including sailboats, powerboats, kayaks, and canoes, where a fin helps maintain a straight course.

Fixed skegs are permanently attached and provide continuous support for tracking. Retractable skegs can be deployed or retracted to reduce drag or to clear shallow water. Some boats use a rudder mounted through or above a skeg, forming a combined rudder-skeg arrangement that provides steering along with added strength and protection for the rudder.

In kayaks and canoes, skegs are often a separate fin that can be lowered into the water to increase straight-line performance in gusty conditions. Surfboards and some small windsurfing boards also use skegs (fin systems) to stabilize direction and improve rail-to-rail control; in these cases they resemble fins rather than rudders.

Materials range from fiberglass and carbon fiber composites to stainless steel or aluminum. Skegs are subject to wear and impact damage and should be inspected for cracks, deformation, or attachment loosening. Proper sizing and fairing are important to minimize drag and ensure effective performance.