Curves of form

The curves of form are the family of hydrostatic properties plotted against draft for the upright, level hull: displacement, TPC (tons per centimeter immersion), MCT1cm (moment to change trim one centimeter), KB, BM, KM, LCB, and LCF. They are derived by integrating the offsets at successive waterlines. A naval architect enters at the operating draft and reads every quantity needed for a stability and trim calculation. The set is computed for design trim, usually even keel, and forms the backbone of the trim and stability booklet. Cross-curves of stability extend this to large heel angles, which the upright curves of form do not cover.