Keelboats & Keel Yachts for Sale

Keelboat or keel yacht – what exactly does that mean?

In nautical terms, keel yachts and/or keelboats are sailboats or sailing yachts with a ballast keel fitted to the underside of the hull. This keel provides weight stability when the yacht or boat heels under the sail area set, depending on wind strength and wind angle.

Keelboats or keel yachts – the definition.

In nautical terms, keel yachts and/or keelboats are a sailboat or a sailing yacht with a ballast keel attached to the underside of the hull. This keel provides weight stability when the yacht or boat heels (leans over) due to the sail area set, depending on wind strength and wind angle. The keel then creates a hydrodynamic counterweight to windward that is designed to prevent the yacht or boat from capsizing. A keel also reduces the leeway of a sailing yacht when sailing upwind – more or less effectively, depending on the keel shape.

The advantages of a keel?

Most keels are designed so that the boat rights itself again without outside help after a simple capsize – sails and mast on the surface of the water (the roly-poly effect).
In heavy weather at sea and in high seas, keel yachts can nevertheless turn turtle (boat rotated 180 degrees, mast under water, keel pointing upwards above the surface). Whether and how quickly the self-righting effect, or righting moment, takes place depends on the height of the incoming waves and on the keel design. Modern offshore yachts such as the IMOCAs, which are sailed single-handed and non-stop around the world, for example, undergo capsize tests. The yachts are capsized with the help of a crane in order to check whether they right themselves again without outside help.
Turning turtle on the open sea mostly causes severe damage to yachts, such as a broken mast or torn sails, can seriously injure people below deck, or catapult an unclipped deck watch overboard.

Keel shapes currently used in boat and yacht building:

• Long keel: Runs horizontally along almost the entire length of the underwater hull and tapers vertically in a hydrodynamic shape. Nowadays mostly found only on classic yachts and replicas.

• Short keel: The term «short» refers to the horizontal length of the keel along the hull in relation to the length of the boat. This version is used on most sailboats and sailing yachts in modern boat building. Paradoxically, the keel fins on short keels are disproportionately long. As a result, the draft of boats with a short keel is usually significantly greater than that of long-keeled boats.

• Keel centerboarder: A centerboard can be raised and lowered from a relatively short keel fin.

• Bilge keel: Two short keels with short keel fins mounted on the sides of the hull. Often used in tidal waters, as the yacht can dry out on its bilge keels without any problem and stays in a horizontal position.

• Lifting keel: Special devices in the yacht allow the keel fin to be raised into the interior of the boat. Particularly suitable for yachts that are transported frequently.

• Swing keel: The keel fin can be tilted/folded up under the hull.

• Canting keel: A usually disproportionately long keel fin with a bulb is raised to one side by an elaborate hydraulic system. This reduces the boat's heel, so it sails more upright. Canting keels are fitted almost exclusively in offshore racing yachts. Their righting moment is especially appreciated by shorthanded crews (no more than two people on board). Once the canting keel has been swung to windward, the increased leeway this creates has to be counteracted with additional daggerboards.

You can find a detailed definition of the keel types used on Boat24 in our magazine: Keel types