International America's Cup Class
The International Americas Cup Class are a class of racing yacht, developed for the America's Cup between 1992 and 2007. These yachts, while not identical, were all designed to the same formula to offer designers the freedom to experiment whilst keeping the boats sufficiently comparable to race in real time; the class was established for the 1992 America's Cup because of perceived shortcomings of the 12-metre class, used in the America's Cup since 1958. In addition to the America's Cup, IACC yachts were raced in other regattas, including the IACC worlds. IACC sail numbers were issued according to the date when the ACM measurement committee decided that the hull has reached a certain stage of completion; the number came in two parts: the hull number. The country code changed. Only one boat had a sail number issued twice as in the case of RUS-62, a new boat based on the modified hull of RUS-24 and re-registered as RUS-62. Version 5.0 of the International America's Cup Class Rule was issued on December 15, 2003.
Copyright is held jointly by the'Challenger of Record' BMW Oracle Racing. Typical parameters of an IACC yacht were: length: 25 metres weight: 24 tonnes height of the mast: 35 metres weight of the bulb: 19 tonnes sail surface area: 325 square metres upwind, 750 square metres downwind crew: 17+ "18th man" 2007 America's Cup Winner - Alinghi SUI-100, Switzerland 2003 America's Cup Winner - Alinghi SUI-64, Switzerland 2000 America's Cup Winner - Team New Zealand NZL-60, Team New Zealand, New Zealand 1995 America's Cup Winner - Team New Zealand NZL-32, New Zealand 1992 America's Cup Winner - America³ USA-23, United States 2007 Louis Vuitton Cup Winner - Emirates Team New Zealand NZL-92, New Zealand 2003 Louis Vuitton Cup Winner - Alinghi SUI-64, Switzerland 2000 Louis Vuitton Cup Winner - Prada Challenge ITA-45, Italy 1995 Louis Vuitton Cup Winner- Team New Zealand NZL-32, New Zealand 1992 Louis Vuitton Cup Winner - Il Moro di Venezia ITA-16, Italy The 2007 America’s Cup saw the introduction of the ‘’Umpire Signaling System’’ which allowed the Umpires to notify the two boats regarding their position in relation to each other when overtaking and their position relating to a mark of the course when in close proximity of the mark.
On both the defender and the challenger there was a display unit with three LED lights coloured green and white respectively. GREEN lamp: ZONE ENTRY. Status ‘On’ indicates that the leading yacht has entered a zone of two or three boat lengths from the mark. AMBER lamp: OVERLAP. Status ‘On’ indicates that the bow of the overtaking yacht is overlapping the stern of the leading yacht and there is no restriction on the leeward yacht to steer a direct course for the next mark; the leeward yacht may point higher than the direct course to the next mark causing the windward yacht to either tack or sail higher than needed to the next mark. WHITE lamp: RULE 17.1. Status ‘On’ indicates that the depth of the overlap has increased to the point where the yacht to leeward must now steer a proper course to the mark and hence cannot point higher and force the overtaking yacht to either tack or sail a higher course to the next mark; the rules of racing define what tactics/maneuvers are permissible when a yacht nears a mark and when a trailing yacht starts to overtake the boat in front.
The purpose of the USS is to remove doubt and associated protests caused by competitors having differing opinions of either their positions relative to each other or their distance from marks and performing tactical maneuvers prohibited by the racing rules. The system was developed by Pilotfish Networks AB. Formula: L + 1.25 × S − 9.8 × D S P 3 0.686 ≤ 24.000 m e t r e s DSP: displacement in cubic metres. The boats had to carry what was known as the "18th man", a passenger or the equivalent weight up to 100 kg; this was a sought-after position filled by a celebrity or a representative from one of the key sponsors to the team. After the conclusion of the 2007 America's Cup, Brad Butterworth announced on behalf of Alinghi and America's Cup Management that a new design of boat would be sailed in the next edition of the America's Cup; the feeling was that the existing IACC rule had evolved as far as was practical and that in the spirit of the America's Cup, a new design challenge was needed. Alinghi promulgated a new design, called the AC 90.
Plans to introduce this class were superseded by Alinghi's loss to BMW Oracle in the 2010 America's Cup and the subsequent creation of the AC72 class of catamarans. The last IACC yacht completed was hull number 100, the 2007 defender. Maxi yacht List of International America's Cup Class Yachts Louis Vuitton Cup
2007 Louis Vuitton Cup
The 2007 Louis Vuitton Cup held in Valencia, from April 16 to June 6 was the event used to select the challenger for the 2007 America's Cup. Eleven potential challengers competed in the competition which consisted of two round robins, two semi-finals and a final; the winner was Emirates Team New Zealand, who challenged the defender Alinghi in June 2007 for the America's Cup. Managed by Grant Dalton and skippered by Dean Barker, the crew included Terry Hutchinson. Ben Ainslie and Kelvin Harrap sailed the trial boat. Skippered by Chris Dickson, the crew included Gavin Brady, Phil Jameson, Paul Westlake, Scott Crawford, Alberto Barovier, Brad Webb, Brian MacInnes, Joe Spooner, Ross Halcrow, Robbie Naismith, Bertrand Pacé, Craig Monk, Carl Williams, Peter Isler and owner Larry Ellison. Luna Rossa Challenge was led by helmsman James Spithill; the crew included Peter Gilmour, Francesco Bruni, mid-bowman Max Sirena, Emanuele Marino, Manuel Modena, Marco Montis, Benjamin Durham, Andy Horton, Michele Cannoni, Gilberto Nobili, Joey Newton, Shannon Falcone, Christian Kamp, Romolo Ranieri, Emanuele Marino, Andrew Taylor, Matteo Plazzi, Simone de Mari, Massimo Gherarducci, Paolo Bassani, Alan Smith, Olympians Torben Grael, Philippe Presti, Michele Ivaldi, Magnus Augustson and Charles and Jonathan McKee.
Skippered by Luis Doreste, the boat was helmed by Karol Jabłoński and John Cutler was the teams tactician and technical director. The team was coached by Paul Cayard. Magnus Holmberg skippered Victory Challenge; the afterguard included Stefan Rahn, Santiago Lange, Thierry Fouchier, Morgan Larson. The crew included six members of the former GBR Challenge. Jeremy Scantlebury was the sailing team manager. Vasco Vascotto was the skipper for Mascalzone Latino, which included helmsman Flavio Favini, Cameron Dunn, Jes Gram-Hansen, Andrea Pavan, Chris Dougall, Pierluigi De Felice, Giuseppe Brizzi, Davide Scarpa, Nacho Postigo, Giulio Giovanella and funder Vincenzo Onorato. South Africa's first challenge, Team Shosholoza was skippered by Ian Ainslie; the crew included Tommaso Chieffi. Managed by Dawn Riley, Areva Challenge was led by Thierry Peponnet and included Sebastien Col, Tanguy Cariou, Frederic Guilmin, Jean François Cuzon, Jim Turner, Wade Morgan. From Italy, +39 Challenge included non-sailing skipper Luca Devoti, helmsman Iain Percy, other Olympic competitors such as Rafael Trujillo and Ian Walker.
The rest of the crew was navigator Bruno Zirilli. United Internet Team Germany was skippered by Jesper Bank and included America's Cup veteran David Dellenbaugh. Pierre Mas was the skipper of China Team. Only two of the crew were Chinese. Round robin 2 was completed on May 9, 2007. Teams had accrued bonus points based on their results in the Louis Vuitton Acts which took place in the preceding years. For the round-robin races, two points were awarded for zero for a defeat; the first four boats progressed to the semi-finals stage of the Louis Vuitton Cup and the remainder were eliminated. As winner of the round-robin events Emirates Team New Zealand won the right to choose their opponent; the 2007 Louis Vuitton Cup started with all races postponed for the first four days of competition due to light and variable winds. There were rumors that BMW Oracle was planning on rotating the crew off the boat because they were running out of stories to tell as they sat in the boat waiting for wind. To entertain fans, some teams came up with interesting stunts.
For instance, United Internet Germany came up with a way to wakeboard, by having their largest sail trimmers pull on the wakeboarder using the jib trimming system. +39, an Italian challenger, used the windless days off to continue making repairs to their mast, which shattered in a starboard-port situation with Internet Team Germany two weeks earlier, completed mast repairs by the time racing had commenced. The highlights for the week were not on the water, but rather off it; the Measurement Committee released the final rule interpretations. The rules state that any cup team can remain anonymous. Additionally, any interpretation by the committee stays private for 6 months; every cup team and all the media was trying to find out more about two of the final interpretations. It seems that one boat may have found a significant advantage, but everyone would have to wait until the end of the Cup to find out who and what had happened. Racing was scheduled to start on April 16, 2007, but did not get underway until April 20, 2007.
All the scheduled races for April 21, 2007, were postponed by the race committee to April 22, 2007, due to light winds. Some of the scheduled races for April 22, 2007, all of the races on April 23, 2007, were postponed by the race committee until April 24, 2007, due to poor wind conditions; some of the scheduled races for April 27, 2007, were postponed by the race committee until April 28, 2007, due to light and variable winds. The following week brought a little wind, although most days the race committee postponed races for wind, they were able to race most days. Although many of
Italy the Italian Republic, is a country in Southern Europe. Located in the middle of the Mediterranean Sea, Italy shares open land borders with France, Austria and the enclaved microstates San Marino and Vatican City. Italy covers an area of 301,340 km2 and has a temperate seasonal and Mediterranean climate. With around 61 million inhabitants, it is the fourth-most populous EU member state and the most populous country in Southern Europe. Due to its central geographic location in Southern Europe and the Mediterranean, Italy has been home to a myriad of peoples and cultures. In addition to the various ancient peoples dispersed throughout modern-day Italy, the most famous of which being the Indo-European Italics who gave the peninsula its name, beginning from the classical era and Carthaginians founded colonies in insular Italy and Genoa, Greeks established settlements in the so-called Magna Graecia, while Etruscans and Celts inhabited central and northern Italy respectively; the Italic tribe known as the Latins formed the Roman Kingdom in the 8th century BC, which became a republic with a government of the Senate and the People.
The Roman Republic conquered and assimilated its neighbours on the peninsula, in some cases through the establishment of federations, the Republic expanded and conquered parts of Europe, North Africa and the Middle East. By the first century BC, the Roman Empire emerged as the dominant power in the Mediterranean Basin and became the leading cultural and religious centre of Western civilisation, inaugurating the Pax Romana, a period of more than 200 years during which Italy's technology, economy and literature flourished. Italy remained the metropole of the Roman Empire; the legacy of the Roman Empire endured its fall and can be observed in the global distribution of culture, governments and the Latin script. During the Early Middle Ages, Italy endured sociopolitical collapse and barbarian invasions, but by the 11th century, numerous rival city-states and maritime republics in the northern and central regions of Italy, rose to great prosperity through shipping and banking, laying the groundwork for modern capitalism.
These independent statelets served as Europe's main trading hubs with Asia and the Near East enjoying a greater degree of democracy than the larger feudal monarchies that were consolidating throughout Europe. The Renaissance began in Italy and spread to the rest of Europe, bringing a renewed interest in humanism, science and art. Italian culture flourished, producing famous scholars and polymaths such as Michelangelo, Leonardo da Vinci, Raphael and Machiavelli. During the Middle Ages, Italian explorers such as Marco Polo, Christopher Columbus, Amerigo Vespucci, John Cabot and Giovanni da Verrazzano discovered new routes to the Far East and the New World, helping to usher in the European Age of Discovery. Italy's commercial and political power waned with the opening of trade routes that bypassed the Mediterranean. Centuries of infighting between the Italian city-states, such as the Italian Wars of the 15th and 16th centuries, left the region fragmented, it was subsequently conquered and further divided by European powers such as France and Austria.
By the mid-19th century, rising Italian nationalism and calls for independence from foreign control led to a period of revolutionary political upheaval. After centuries of foreign domination and political division, Italy was entirely unified in 1871, establishing the Kingdom of Italy as a great power. From the late 19th century to the early 20th century, Italy industrialised, namely in the north, acquired a colonial empire, while the south remained impoverished and excluded from industrialisation, fuelling a large and influential diaspora. Despite being one of the main victors in World War I, Italy entered a period of economic crisis and social turmoil, leading to the rise of a fascist dictatorship in 1922. Participation in World War II on the Axis side ended in military defeat, economic destruction and the Italian Civil War. Following the liberation of Italy and the rise of the resistance, the country abolished the monarchy, reinstated democracy, enjoyed a prolonged economic boom and, despite periods of sociopolitical turmoil became a developed country.
Today, Italy is considered to be one of the world's most culturally and economically advanced countries, with the sixth-largest worldwide national wealth. Its advanced economy ranks eighth-largest in the world and third in the Eurozone by nominal GDP. Italy owns the third-largest central bank gold reserve, it has a high level of human development, it stands among the top countries for life expectancy. The country plays a prominent role in regional and global economic, military and diplomatic affairs. Italy is a founding and leading member of the European Union and a member of numerous international institutions, including the UN, NATO, the OECD, the OSCE, the WTO, the G7, the G20, the Union for the Mediterranean, the Council of Europe, Uniting for Consensus, the Schengen Area and many more; as a reflection
Spain the Kingdom of Spain, is a country located in Europe. Its continental European territory is situated on the Iberian Peninsula, its territory includes two archipelagoes: the Canary Islands off the coast of Africa, the Balearic Islands in the Mediterranean Sea. The African enclaves of Ceuta, Peñón de Vélez de la Gomera make Spain the only European country to have a physical border with an African country. Several small islands in the Alboran Sea are part of Spanish territory; the country's mainland is bordered to the south and east by the Mediterranean Sea except for a small land boundary with Gibraltar. With an area of 505,990 km2, Spain is the largest country in Southern Europe, the second largest country in Western Europe and the European Union, the fourth largest country in the European continent. By population, Spain is the fifth in the European Union. Spain's capital and largest city is Madrid. Modern humans first arrived in the Iberian Peninsula around 35,000 years ago. Iberian cultures along with ancient Phoenician, Greek and Carthaginian settlements developed on the peninsula until it came under Roman rule around 200 BCE, after which the region was named Hispania, based on the earlier Phoenician name Spn or Spania.
At the end of the Western Roman Empire the Germanic tribal confederations migrated from Central Europe, invaded the Iberian peninsula and established independent realms in its western provinces, including the Suebi and Vandals. The Visigoths would forcibly integrate all remaining independent territories in the peninsula, including Byzantine provinces, into the Kingdom of Toledo, which more or less unified politically and all the former Roman provinces or successor kingdoms of what was documented as Hispania. In the early eighth century the Visigothic Kingdom fell to the Moors of the Umayyad Islamic Caliphate, who arrived to rule most of the peninsula in the year 726, leaving only a handful of small Christian realms in the north and lasting up to seven centuries in the Kingdom of Granada; this led to many wars during a long reconquering period across the Iberian Peninsula, which led to the creation of the Kingdom of Leon, Kingdom of Castile, Kingdom of Aragon and Kingdom of Navarre as the main Christian kingdoms to face the invasion.
Following the Moorish conquest, Europeans began a gradual process of retaking the region known as the Reconquista, which by the late 15th century culminated in the emergence of Spain as a unified country under the Catholic Monarchs. Until Aragon had been an independent kingdom, which had expanded toward the eastern Mediterranean, incorporating Sicily and Naples, had competed with Genoa and Venice. In the early modern period, Spain became the world's first global empire and the most powerful country in the world, leaving a large cultural and linguistic legacy that includes more than 570 million Hispanophones, making Spanish the world's second-most spoken native language, after Mandarin Chinese. During the Golden Age there were many advancements in the arts, with world-famous painters such as Diego Velázquez; the most famous Spanish literary work, Don Quixote, was published during the Golden Age. Spain hosts the world's third-largest number of UNESCO World Heritage Sites. Spain is a secular parliamentary democracy and a parliamentary monarchy, with King Felipe VI as head of state.
It is a major developed country and a high income country, with the world's fourteenth largest economy by nominal GDP and sixteenth largest by purchasing power parity. It is a member of the United Nations, the European Union, the Eurozone, the Council of Europe, the Organization of Ibero-American States, the Union for the Mediterranean, the North Atlantic Treaty Organization, the Organisation for Economic Co-operation and Development, Organization for Security and Co-operation in Europe, the Schengen Area, the World Trade Organization and many other international organisations. While not an official member, Spain has a "Permanent Invitation" to the G20 summits, participating in every summit, which makes Spain a de facto member of the group; the origins of the Roman name Hispania, from which the modern name España was derived, are uncertain due to inadequate evidence, although it is documented that the Phoenicians and Carthaginians referred to the region as Spania, therefore the most accepted etymology is a Semitic-Phoenician one.
Down the centuries there have been a number of accounts and hypotheses: The Renaissance scholar Antonio de Nebrija proposed that the word Hispania evolved from the Iberian word Hispalis, meaning "city of the western world". Jesús Luis Cunchillos argues that the root of the term span is the Phoenician word spy, meaning "to forge metals". Therefore, i-spn-ya would mean "the land where metals are forged", it may be a derivation of the Phoenician I-Shpania, meaning "island of rabbits", "land of rabbits" or "edge", a reference to Spain's location at the end of the Mediterranean. The word in question means "Hyrax" due to Phoenicians confusing the two animals. Hispania may derive from the poetic use of the term Hesperia, reflecting the Greek perception of Italy as a "western land" or "land of the setting sun" (Hesperia
Société Nautique de Genève
The Société Nautique de Genève is a yacht club based in Geneva. It was founded in 1872 with the goal of developing nautical sports and high level sailors; the club has about 3000 members. The club held the America's Cup from 2003 until 2010, staging one successful defense in 2007 with its Alinghi syndicate; the club is active in yacht racing and high-performance catamarans have been developed for the lake. The design of Alinghi 5, the defender of the 2010 America's Cup, was influenced by those racing catamarans; the best-known event, the "Bol d'Or" runs from Geneva to the end of the back. America's Cup Management announced on 5 July 2007 that the protocol for the 2010 America's Cup had been agreed between the defending yacht club, the Société Nautique de Genève of Switzerland and Challenger of Record, Club Náutico Español de Vela of Spain; however this arrangement did not survive a legal challenge from BMW Oracle Racing, who argued that Club Náutico Español de Vela was not a valid Challenger of Record due to non-compliance with the terms of the America's Cup Deed of Gift.
After extensive court action, Golden Gate Yacht Club was declared Challenger of Record and sailed against Société Nautique de Genève, in the 2010 America's Cup during February 2010, in Valencia, Spain. The competing boats, Alinghi 5 and USA 17 were both 90-foot multihulls. USA 17's rigid wing sail provided a decisive advantage and USA 17 won the first two races in a best of three race contest to win 2010 America's Cup on behalf of the Golden Gate Yacht Club. Website of the Société Nautique de Genève
Switzerland the Swiss Confederation, is a country situated in western and southern Europe. It consists of 26 cantons, the city of Bern is the seat of the federal authorities; the sovereign state is a federal republic bordered by Italy to the south, France to the west, Germany to the north, Austria and Liechtenstein to the east. Switzerland is a landlocked country geographically divided between the Alps, the Swiss Plateau and the Jura, spanning a total area of 41,285 km2. While the Alps occupy the greater part of the territory, the Swiss population of 8.5 million people is concentrated on the plateau, where the largest cities are to be found: among them are the two global cities and economic centres Zürich and Geneva. The establishment of the Old Swiss Confederacy dates to the late medieval period, resulting from a series of military successes against Austria and Burgundy. Swiss independence from the Holy Roman Empire was formally recognized in the Peace of Westphalia in 1648; the country has a history of armed neutrality going back to the Reformation.
It pursues an active foreign policy and is involved in peace-building processes around the world. In addition to being the birthplace of the Red Cross, Switzerland is home to numerous international organisations, including the second largest UN office. On the European level, it is a founding member of the European Free Trade Association, but notably not part of the European Union, the European Economic Area or the Eurozone. However, it participates in the Schengen Area and the European Single Market through bilateral treaties. Spanning the intersection of Germanic and Romance Europe, Switzerland comprises four main linguistic and cultural regions: German, French and Romansh. Although the majority of the population are German-speaking, Swiss national identity is rooted in a common historical background, shared values such as federalism and direct democracy, Alpine symbolism. Due to its linguistic diversity, Switzerland is known by a variety of native names: Schweiz. On coins and stamps, the Latin name – shortened to "Helvetia" – is used instead of the four national languages.
Switzerland is one of the most developed countries in the world, with the highest nominal wealth per adult and the eighth-highest per capita gross domestic product according to the IMF. Switzerland ranks at or near the top globally in several metrics of national performance, including government transparency, civil liberties, quality of life, economic competitiveness and human development. Zürich and Basel have all three been ranked among the top ten cities in the world in terms of quality of life, with the first ranked second globally, according to Mercer in 2018; the English name Switzerland is a compound containing Switzer, an obsolete term for the Swiss, in use during the 16th to 19th centuries. The English adjective Swiss is a loan from French Suisse in use since the 16th century; the name Switzer is from the Alemannic Schwiizer, in origin an inhabitant of Schwyz and its associated territory, one of the Waldstätten cantons which formed the nucleus of the Old Swiss Confederacy. The Swiss began to adopt the name for themselves after the Swabian War of 1499, used alongside the term for "Confederates", used since the 14th century.
The data code for Switzerland, CH, is derived from Latin Confoederatio Helvetica. The toponym Schwyz itself was first attested in 972, as Old High German Suittes perhaps related to swedan ‘to burn’, referring to the area of forest, burned and cleared to build; the name was extended to the area dominated by the canton, after the Swabian War of 1499 came to be used for the entire Confederation. The Swiss German name of the country, Schwiiz, is homophonous to that of the canton and the settlement, but distinguished by the use of the definite article; the Latin name Confoederatio Helvetica was neologized and introduced after the formation of the federal state in 1848, harking back to the Napoleonic Helvetic Republic, appearing on coins from 1879, inscribed on the Federal Palace in 1902 and after 1948 used in the official seal.. Helvetica is derived from the Helvetii, a Gaulish tribe living on the Swiss plateau before the Roman era. Helvetia appears as a national personification of the Swiss confederacy in the 17th century with a 1672 play by Johann Caspar Weissenbach.
Switzerland has existed as a state in its present form since the adoption of the Swiss Federal Constitution in 1848. The precursors of Switzerland established a protective alliance at the end of the 13th century, forming a loose confederation of states which persisted for centuries; the oldest traces of hominid existence in Switzerland date back about 150,000 years. The oldest known farming settlements in Switzerland, which were found at Gächlingen, have been dated to around 5300 BC; the earliest known cultural tribes of the area were members of the Hallstatt and La Tène cultures, named after the archaeological site of La Tène on the north side of Lake Neuchâtel. La Tène culture developed and flourished during the late Iron Age from around 450 BC under some influence from the Gree
Sailing employs the wind—acting on sails, wingsails or kites—to propel a craft on the surface of the water, on ice or on land over a chosen course, part of a larger plan of navigation. A course defined with respect to the true wind direction is called a point of sail. Conventional sailing craft cannot derive power from sails on a point of sail, too close into the wind. On a given point of sail, the sailor adjusts the alignment of each sail with respect to the apparent wind direction to mobilize the power of the wind; the forces transmitted via the sails are resisted by forces from the hull and rudder of a sailing craft, by forces from skate runners of an iceboat, or by forces from wheels of a land sailing craft to allow steering the course. In the 21st century, most sailing represents a form of sport. Recreational sailing or yachting can be divided into cruising. Cruising can include extended offshore and ocean-crossing trips, coastal sailing within sight of land, daysailing; until the mid of the 19th century, sailing ships were the primary means for marine commerce, this period is known as Age of Sail.
Throughout history sailing has been instrumental in the development of civilization, affording humanity greater mobility than travel over land, whether for trade, transport or warfare, the capacity for fishing. The earliest representation of a ship under sail appears on a painted disc found in Kuwait dating between 5500 and 5000 BCE. Polynesian oceanfarers traveled vast distances of open ocean in outrigger canoes using navigation methods such as stick charts. Advances in sailing technology from the Middle Ages onward enabled Arab, Chinese and European explorers to make longer voyages into regions with extreme weather and climatic conditions. There were improvements in sails and rigging. From the 15th century onwards, European ships went further north, stayed longer on the Grand Banks and in the Gulf of St. Lawrence, began to explore the Pacific Northwest and the Western Arctic. Sailing has contributed to many great explorations in the world. According to Jett, the Egyptians used a bipod mast to support a sail that allowed a reed craft to travel upriver with a following wind, as late as 3,500 BCE.
Such sails evolved into the square-sail rig. Such rigs could not sail much closer than 80° to the wind. Fore-and-aft rigs appear to have evolved in Southeast Asia—dates are uncertain—allowing for rigs that could sail as close as 60–75° off the wind; the physics of sailing arises from a balance of forces between the wind powering the sailing craft as it passes over its sails and the resistance by the sailing craft against being blown off course, provided in the water by the keel, underwater foils and other elements of the underbody of a sailboat, on ice by the runners of an ice boat, or on land by the wheels of a sail-powered land vehicle. Forces on sails depend on the speed and direction of the craft; the speed of the craft at a given point of sail contributes to the "apparent wind"—the wind speed and direction as measured on the moving craft. The apparent wind on the sail creates a total aerodynamic force, which may be resolved into drag—the force component in the direction of the apparent wind—and lift—the force component normal to the apparent wind.
Depending on the alignment of the sail with the apparent wind, lift or drag may be the predominant propulsive component. Depending on the angle of attack of a set of sails with respect to the apparent wind, each sail is providing motive force to the sailing craft either from lift-dominant attached flow or drag-dominant separated flow. Additionally, sails may interact with one another to create forces that are different from the sum of the individual contributions each sail, when used alone; the term "velocity" refers both to direction. As applied to wind, apparent wind velocity is the air velocity acting upon the leading edge of the most forward sail or as experienced by instrumentation or crew on a moving sailing craft. In nautical terminology, wind speeds are expressed in knots and wind angles in degrees. All sailing craft reach a constant forward velocity for a given true wind velocity and point of sail; the craft's point of sail affects its velocity for a given true wind velocity. Conventional sailing craft cannot derive power from the wind in a "no-go" zone, 40° to 50° away from the true wind, depending on the craft.
The directly downwind speed of all conventional sailing craft is limited to the true wind speed. As a sailboat sails further from the wind, the apparent wind becomes smaller and the lateral component becomes less. In order to act like an airfoil, the sail on a sailboat is sheeted further out as the course is further off the wind; as an iceboat sails further from the wind, the apparent wind increases and the boat speed is highest on the broad reach. In order to act like an airfoil, the sail on an iceboat is sheeted in for all three points of sail. Lift on a sail, acting as an airfoil, occurs in a direction perpendicular to the incident airstream and is a result of pressure differences between the windward and leeward surfaces and depends on angle of attack, sail shape, air density, speed of the apparent wind; the lift force results from the average pressure on the windward surface of the sail being higher than the ave