Keel

A keel is the main underwater longitudinal structure of a vessel, usually running along the centreline beneath the hull. On sailing boats it provides lateral resistance to reduce leeway and, when ballasted, helps keep the yacht upright. Keels may be full-length, fin, bulb, wing or lifting designs, each affecting stability, manoeuvrability and depth requirements.

For boaters, keel shape and depth influence passage planning, marina access, grounding risk and performance to windward. Knowing your Draught is essential when crossing bars, entering shallow anchorages or using tidal windows. A well-designed keel works with the Hull and Rudder to improve tracking, control and safety in heavy weather.

Keel characteristics also affect routing assumptions, speed prediction and handling in waves. PredictWind Weather Routing and AI Polars can better reflect real-world performance when vessel data and logged sailing behaviour account for keel-driven differences in pointing ability, leeway and speed through varying wind and sea state.