Besides the usual numbers used to describe a sailboat—length, beam, draft and sail area—CW’s Boat of the Year judges sometimes rely on sail area/displacement and displacement/length ratios, as well as decibels for sound while motoring, to compare similar vessels (see specs, pages 64-65). One caveat, because sailboat design and building materials change over time: Design ratios work best when looking at boats of a similar era rather than comparing, say, a 1975 cruiser to its modern counterpart.
Let’s start with displacement/length. Displacement is a measure of how much water a particular hull form displaces, and length is, well, length. In general terms, the lower the D/L ratio is, the less water is being displaced for a given length, which would indicate better performance. Performance, though, often reflects speed but not…
