A sailboat or sailing boat is a boat propelled partly or entirely by sails smaller than a sailing ship. distinctions in what constitutes a sailing boat and ship vary by region and maritime culture. distinctions in what constitutes a sailing boat and ship vary by region and maritime culture.. How sailboats measure up. design ratios tell a story, but to get the real picture about a vessel, sail area, displacement, and ballast deserve a longer look. cruising-boat design drifted away from raceboat design, and sail plans began to change. b/d doesn’t take into account the location of the ballast. take a boat that has a total. In sailboats, the ballast is usually part of the keel, a large fin-like structure under the boat that serves two purposes (figure 1). it holds the ballast, and it also prevents the boat from being blown sideways by the wind..
Comparing design ratios. the beneteau sense 46 is a typical modern cruising boat, with an sa/d of 19, a ballast ratio of 28 percent and a d/l of 159. note that this particular d/l was determined using the light-ship displacement. finally, there is the ballast ratio, or the amount of ballast a design is carrying. unlike the first two. Beam, ballast & displacement as they relate to seakeeping . this is very much counter to the often assumed requirement for a specific 'ballast ratio' on sail boats, or that there must be a certain amount of ballast present for the safety of a power boat. for any new design, after a thorough weight analysis is done in order to determine. Stability, fundamentally, is what prevents a boat from being turned over and capsized. whether you are a cruiser or a racer, it is a desirable characteristic. a boat's shape, particularly its transverse hull form, has an enormous impact on how stable it is. this so-called "form stability" is one of.