Sailing yacht
[1][2][3] There is no standard definition, so the term applies here to sailing vessels that have a cabin with amenities that accommodate overnight use.
To be termed a "yacht", as opposed to a "boat", such a vessel is likely to be at least 33 feet (10 m) in length and have been judged to have good aesthetic qualities.
jachten, which means "hunt"), and originally referred to light, fast sailing vessels that the Dutch Republic navy used to pursue pirates and other transgressors around and into the shallow waters of the Low Countries.
Upon his restoration to the English crown, Charles commissioned a series of royal yachts, which included at least one experimental catamaran.
The first recorded yacht race between two vessels occurred in 1661, followed by the first open sailing competition in 1663 in English waters.
Boatbuilders, who had been making fast vessels both for smugglers and the government revenue cutters, turned their skills again to yachts.
[8] The fast yachts of the early 19th century were typically luggers, schooners, or sloops with fore-and-aft rigs.
By the 1850s, yachts featured large sail areas, a narrow beam, and a deeper draft than was customary until then.
[8] English and American design philosophies for sailing yachts diverged in the early 1800s: the English favoring a narrow beam (width) and a deep-draft keel and the Americans favoring a broad beam and a shallow draft with a moveable centerboard to provide lateral resistance and righting moment.
American yachtsmen, in turn, found that their shallow "skimming-dish" designs were not faster or safer than the visiting English yachts.
[7][10] By the turn of the 20th century, racing yachts featured long overhangs, fore and aft, and a narrow, deep keel by historic standards.
Along the way, yacht designers discovered that handicapping rules based on tonnage or length were not good indicators of performance, although they remained a basis for taxation in the two home countries.
[11] In the 1930s yacht hulls were designed with a "fisherman" underbody, whereby the slope of the bow continued to the fullest extent of the draft and then carried horizontally aft.
Successful designers of this era were Olin Stephens, Philip Rhodes, Aage Nielson, and C. Raymond Hunt.
This rule was augmented with the International Measurement System (IMS) to assure safe designs for extreme conditions, following the disastrous 1979 Fastnet Race in which only 86 of the 303 participants finished owing to failed equipment and loss of 19 lives and five boats.
[20] Traditionally, all sailing yachts were made of wood, using a wooden keel and ribs, clad with planks.
A keel-stepped mast is better able to withstand a failure of its supporting standing rigging, but requires a penetration of the cabin roof and the need for waterproofing.
A cruising yacht's deck usually has safety line to protect the crew from falling overboard and a bow pulpit to facilitate handling the jib and the anchor.
Target shaft horsepower for the engine per unit of displacement is related to hull speed per square root of waterline length all to the third power.
As to sheer, traditional yachts have the deck follow a curve below an imaginary straight line from stem (top of bow) to stern.
[22] Underwater foils can become more specialized, starting with a higher-aspect ratio fin keel with hydrodynamically efficient bulbs for ballast.
