When it comes to picking a sailboat there can be a lot of concerns regarding equipment appropriate to your use. What kinds of sails you pick you can determine if your going to use the boat for speed or day sailing. The number of sails determines the number of sheets you have and if a deck organizer is needed. Likewise, how you plan to enjoy your boat determines the kind of keel you will want.
In general, most sailboats that are over 30 feet in length have fixed keels, while sailboats less than 15 feet have a fixed keel or a retractable centerboard. However, there are also daggerboards and other designs to consider based on a number of implementations.
A centerboard provides for a more stable day on the sea. It allows more balance and even autopilot. In addition, a centerboard is more resistant to wearing and tear as well as bumping into things like reefs or the sea floor in shallow water. The opposite of having a centerboard is having a keel.
Either retractable or fixed, a keel gives boaters a more hands-on experience and more control when it comes to turning, stopping and riding the waves. A keeled boat is a necessity on a sailboat, regardless of the size. Otherwise it would capsize with the first gust of wind. Retractable keels, however, allow boats in shallower water and even beaching. But fixed keels are always in the correct position for ultimate counterbalance in open water.
Ultimately, if you are more concerned with deep water sailing and have a larger, typically seafaring vessel, you will want a fixed keel. This is best for the the sailor concerned with extensive trips and racing, given the added stability. However, if you are more of a bay-lining day sailor, who enjoys beaching his boat and staying close to shore- especially in shallow, calm water- a retractable keel may be exactly what you’re looking for.