Keelboats: ballast, keels and rigs.

What a keelboat is

Wikipedia describes a keelboat as a sailboat with a keel and ballast that help keep it upright, and says it typically has a cabin. That is the main contrast with a dinghy, which has neither. Most modern keelboats have fixed fin keels with considerable draft, though shoal-draft and lifting-keel designs also exist.

Wikipedia adds that monohulls rely on ballast for stability, usually have displacement hulls, and can sink if flooded unless they are built with flotation. UKSA, a UK sailing school, says keelboats are more stable than dinghies because the fixed keel adds weight and lowers the risk of capsize, which suits beginners who are nervous about small-boat instability. Its example is the Hunter 15.

What the keel does

A keel does two jobs. The ballast in it keeps the boat upright, and its shape stops the boat being pushed sideways. Physics Today explains the second job: when the boat moves through the water at a slight angle to its heading, the keel produces sideways lift that balances the sideways force from the sails, and the forward part of the combined forces drives the boat. The same article says deep, narrow keels are hydrodynamically efficient, and that wings at the bottom of a keel reduce induced drag.

ASA adds a practical point: the keel needs water flowing past it at enough speed to work, and marine growth on it reduces its effectiveness.

Keel types

Draft matters as much as keel shape. The German magazine Yacht says a boat's draught should suit where it will sail. Its example: a boat drawing 1.80 m is unsuitable for the East Frisian Islands, where about 1.40 m or less, plus the ability to dry out, is preferable.

Rig types

A rig is the arrangement of masts and sails. The common ones, as Wikipedia describes them:

UKSA calls the sloop a popular rig that helps beginners learn sail trim. For the parts of the rig, see parts of a boat and rigging and hardware.

Racers and cruisers

Wikipedia separates racing yachts, which put performance ahead of comfort with high-performance rigs and efficient hulls, from cruising yachts, which are built with the comfort and amenities needed for overnight voyages. It names the Star, J/70, Melges 24, Etchells, IMOCA 60 and Sun Fast 30 One Design as racing keelboat classes, and the Catalina 30 and Beneteau Oceanis models as cruising examples.

Keelboats race in two ways:

• Handicap fleets. Wikipedia says PHRF is used mainly for keelboats of about 7 m and longer in North America. IRC, whose rating is calculated from a boat's measurements and data rather than race results, is used at events including Cowes Week, the Rolex Fastnet Race and the Rolex Sydney Hobart, according to US Sailing. See handicap systems.
• One-design classes. The 2025 Rolex Big Boat Series in San Francisco ran one-design classes for the Express 37, J/105 and J/88 alongside ORC handicap divisions. See one-design and Olympic classes.

At the far end of the scale, the 2027 edition of The Ocean Race will be sailed in IMOCA 60s with four crew, including at least one woman, according to Sailing Scuttlebutt. More on offshore races.

On a racing keelboat with a full crew, North Sails describes the tactician leading the afterguard and working with the helmsman, primary trimmers controlling the boat in a straight line, a middle group of headsail trimmers, grinders and pit, and a bow team that hoists and lowers the headsails.

Learning on a keelboat

Keelboat courses name the size of boat they use, which gives a feel for how the steps go up:

For how these lead to chartering a boat on your own, see chartering. For choosing a course, see learning to sail.

Size, if you are thinking of buying

Practical Sailor calls 24 to 28 ft a good size for a first boat. It says boats up to about 24 ft are usually trailerable but may lack headroom for tall sailors, that bluewater and liveaboard cruising become practical at around 30 ft, and that past about 40 ft one person may struggle to handle a boat without modern aids. The full picture, including surveys and running costs, is on buying a boat.

On what to wear aboard, the RYA lists a lifejacket as essential for yacht sailing, along with layers under a waterproof hooded outer layer. See life jackets and foul weather gear.