Austria the Republic of Austria, is a country in Central Europe comprising 9 federated states. Its capital, largest city and one of nine states is Vienna. Austria has an area of 83,879 km2, a population of nearly 9 million people and a nominal GDP of $477 billion, it is bordered by the Czech Republic and Germany to the north and Slovakia to the east and Italy to the south, Switzerland and Liechtenstein to the west. The terrain is mountainous, lying within the Alps; the majority of the population speaks local Bavarian dialects as their native language, German in its standard form is the country's official language. Other regional languages are Hungarian, Burgenland Croatian, Slovene. Austria played a central role in European History from the late 18th to the early 20th century, it emerged as a margraviate around 976 and developed into a duchy and archduchy. In the 16th century, Austria started serving as the heart of the Habsburg Monarchy and the junior branch of the House of Habsburg – one of the most influential royal houses in history.
As archduchy, it was a major component and administrative centre of the Holy Roman Empire. Following the Holy Roman Empire's dissolution, Austria founded its own empire in the 19th century, which became a great power and the leading force of the German Confederation. Subsequent to the Austro-Prussian War and the establishment of a union with Hungary, the Austro-Hungarian Empire was created. Austria was involved in both world wars. Austria is a parliamentary representative democracy with a President as head of state and a Chancellor as head of government. Major urban areas of Austria include Graz, Linz and Innsbruck. Austria is ranked as one of the richest countries in the world by per capita GDP terms; the country has developed a high standard of living and in 2018 was ranked 20th in the world for its Human Development Index. The republic declared its perpetual neutrality in foreign political affairs in 1955. Austria has been a member of the United Nations since 1955 and joined the European Union in 1995.
It is a founding member of the OECD and Interpol. Austria signed the Schengen Agreement in 1995, adopted the euro currency in 1999; the German name for Austria, Österreich, derives from the Old High German Ostarrîchi, which meant "eastern realm" and which first appeared in the "Ostarrîchi document" of 996. This word is a translation of Medieval Latin Marchia orientalis into a local dialect. Another theory says that this name comes from the local name of the mountain whose original Slovenian name is "Ostravica" - because it is steep on both sides. Austria was a prefecture of Bavaria created in 976; the word "Austria" was first recorded in the 12th century. At the time, the Danube basin of Austria was the easternmost extent of Bavaria; the Central European land, now Austria was settled in pre-Roman times by various Celtic tribes. The Celtic kingdom of Noricum was claimed by the Roman Empire and made a province. Present-day Petronell-Carnuntum in eastern Austria was an important army camp turned capital city in what became known as the Upper Pannonia province.
Carnuntum was home for 50,000 people for nearly 400 years. After the fall of the Roman Empire, the area was invaded by Bavarians and Avars. Charlemagne, King of the Franks, conquered the area in AD 788, encouraged colonization, introduced Christianity; as part of Eastern Francia, the core areas that now encompass Austria were bequeathed to the house of Babenberg. The area was known as the marchia Orientalis and was given to Leopold of Babenberg in 976; the first record showing the name Austria is from 996, where it is written as Ostarrîchi, referring to the territory of the Babenberg March. In 1156, the Privilegium Minus elevated Austria to the status of a duchy. In 1192, the Babenbergs acquired the Duchy of Styria. With the death of Frederick II in 1246, the line of the Babenbergs was extinguished; as a result, Ottokar II of Bohemia assumed control of the duchies of Austria and Carinthia. His reign came to an end with his defeat at Dürnkrut at the hands of Rudolph I of Germany in 1278. Thereafter, until World War I, Austria's history was that of its ruling dynasty, the Habsburgs.
In the 14th and 15th centuries, the Habsburgs began to accumulate other provinces in the vicinity of the Duchy of Austria. In 1438, Duke Albert V of Austria was chosen as the successor to his father-in-law, Emperor Sigismund. Although Albert himself only reigned for a year, henceforth every emperor of the Holy Roman Empire was a Habsburg, with only one exception; the Habsburgs began to accumulate territory far from the hereditary lands. In 1477, Archduke Maximilian, only son of Emperor Frederick III, married the heiress Maria of Burgundy, thus acquiring most of the Netherlands for the family. In 1496, his son Philip the Fair married Joanna the Mad, the heiress of Castile and Aragon, thus acquiring Spain and its Italian and New World appendages for the Habsburgs. In 1526, following the Battle of Mohács, Bohemia and the part of Hungary not occupied by the Ottomans came under Austrian rule. Ottoman expansion into Hungary led to frequent conflicts between the two empires evident in the Long War of 1593 to 1606.
The Turks made incursions into Styria nearly 20 times, of which some are c
Doppelmayr Garaventa Group
The Doppelmayr Garaventa Group is an Austrian company that manufactures chairlifts, cable cars, surface tows for ski and amusement parks, as well as urban people movers and material handling systems. To date and Garaventa have produced over 14,600 installations in 89 countries; the Doppelmayr/Garaventa Group was formed in 2002 when Doppelmayr of Wolfurt, Austria merged with Garaventa AG of Switzerland to form the world's largest ropeway manufacturer. Doppelmayr was founded in Wolfurt, Austria, in 1892. In 1967, Artur Doppelmayr, the grandson of the founder, Konrad Doppelmayr, son of Austrian businessman Emil Doppelmayr, became managing director of the company; as alpine recreation expanded around the world during the last half of the 20th century, Artur led and established the Vorarlberg cable car company as the world leader. In 1996, Doppelmayr's holding company purchased a Swiss maker of gondolas and cable cars. In 2002, Doppelmayr acquired a Swiss maker of gondola and cable car cabins; the merger of Doppelmayr and Garaventa was announced in 2001 and completed in 2002.
The company was selected in April 2011 as one of a consortium to build London's Cable Car system. Doppelmayr's core ropeway products include cable cars, detachable chairlifts, fixed grip chairlifts, teleskis that are sold under the Doppelmayr and Garaventa brands; the company pioneered the "3S" tri-cable gondola located in Kitzbühel and Whistler-Blackcomb. It has introduced innovative products such as heated seats on ski lifts. DCC — Doppelmayr Cable Car builds automated people movers for airports and other urban settings; the first installation was completed at Mandalay Bay in Las Vegas in 1999. Other installations can be found at Pearson International Airport in Toronto, Birmingham International Airport in the United Kingdom, Mexico City International Airport in Mexico and Oakland Airport in the United States. More "cable liner shuttles" have been built at Venice in Italy, Caracas in Venezuela and a second one in Las Vegas. Contracts have been awarded for Doppelmayr Cable Car to install an automated people mover in Doha, Qatar.
Doppelmayr Transport Technology sells material-handling ropeway systems. These systems were similar to cable cars and chairlifts designed for people, but fitted with specially designed carriers. In the early 2000s, Doppelmayr developed a cable-driven material-handling ropeway called RopeCon®. RopeCon® is a conveyor system that can transport materials over long distances with little ground disturbance. RopeCon® system installations can be found in Papua New Guinea, Sudan and Austria. CWA Constructions of Olten, was acquired by Doppelmayr in 2001; the subsidiary manufactures cabins, such as gondola and people mover cabins, for Doppelmayr installations as well as for systems built by other manufacturers. The Input Projektentwicklungs division produces mountain systems and amusement rides, such as the experimental Mountain Glider roller coaster in Walibi, Belgium; this project was plagued with problems and the ride was removed. LTW Intralogistics produces automated warehouse technology. Www. LTWUSA.com Garaventa Global Group Doppelmayr Garaventa Group DCC Doppelmayr Cable Car, APM Systems Input Projektentwicklungs GmbH Doppelmayr CTEC CWA-Constructions SA/Corp Doppelmayr Transport Technology GmbH LTW Intralogistics, Inc History
Skiing can be a means of transport, a recreational activity or a competitive winter sport in which the participant uses skis to glide on snow. Many types of competitive skiing events are recognized by the International Olympic Committee, the International Ski Federation. Skiing has a history of five millennia. Although modern skiing has evolved from beginnings in Scandinavia, it may have been practiced more than 100 centuries ago in what is now China, according to an interpretation of ancient paintings; the word "ski" is one of a handful of words. It comes from the Old Norse word "skíð" which means "split piece of wood or firewood". Asymmetrical skis were used in northern Sweden until at least the late 19th century. On one foot, the skier wore a long straight non-arching ski for sliding, a shorter ski was worn on the other foot for kicking; the underside of the short ski was either plain or covered with animal skin to aid this use, while the long ski supporting the weight of the skier was treated with animal fat in a similar manner to modern ski waxing.
Early skiers used spear. The first depiction of a skier with two ski poles dates to 1741. Skiing was used for transport until the mid-19th century, but since has become a recreation and sport. Military ski races were held in Norway during the 18th century, ski warfare was studied in the late 18th century; as equipment evolved and ski lifts were developed during the late 19th and early 20th centuries, two main genres of skiing emerged—Alpine skiing and Nordic skiing. The main difference between the two is the type of ski binding. Called "downhill skiing", Alpine skiing takes place on a piste at a ski resort, it is characterized by fixed-heel bindings that attach at both the toe and the heel of the skier's boot. Ski lifts, including chairlifts, bring skiers up the slope. Backcountry skiing can be accessed by helicopter, snowcat and snowmobile. Facilities at resorts can include night skiing, après-ski, glade skiing under the supervision of the ski patrol and the ski school. Alpine skiing branched off from the older Nordic type of skiing around the 1920s when the advent of ski lifts meant that it was not necessary to walk any longer.
Alpine equipment has specialized to the point. The Nordic disciplines include cross-country skiing and ski jumping, which both use bindings that attach at the toes of the skier's boots but not at the heels. Cross-country skiing may be practiced in undeveloped backcountry areas. Ski jumping is practiced in certain areas that are reserved for ski jumping. Telemark skiing is a ski turning technique and FIS-sanctioned discipline, named after the Telemark region of Norway, it uses equipment similar to Nordic skiing, where the ski bindings are attached only at the toes of the ski boots, allowing the skier's heel to be raised throughout the turn. The following disciplines are sanctioned by the FIS. Many are included in the Winter Olympic Games. Cross-country – Encompasses a variety of formats for cross-country skiing races over courses of varying lengths. Races occur on homologated, groomed courses designed to support classic and free-style events, where skate skiing may be employed; the main competitions are the FIS Cross-Country World Cup and the FIS Nordic World Ski Championships, various cross-country skiing events have been incorporated into the Winter Olympics since its inception in 1924.
The discipline incorporates: cross-country ski marathon events, sanctioned by the Worldloppet Ski Federation. Paralympic cross-country skiing and paralympic biathlon are both included in the Winter Paralympic Games. Ski jumping – Contested at the FIS Ski Jumping World Cup, the FIS Nordic World Ski Championships, the FIS Ski Jumping Grand Prix, the FIS Ski Flying World Championships. Ski jumping has been a regular Olympic discipline at every Winter Games since 1924. Freeriding skiing – This category of skiing includes any practice of the sport on non-groomed terrain. Nordic combined – A combination of cross-country skiing and ski jumping, this discipline is contested at the FIS Nordic Combined World Cup, the FIS Nordic World Ski Championships, at the Winter Olympics. Alpine skiing – Includes downhill, giant slalom, super giant slalom, para-alpine events. There are combined events where the competitors must complete one run of each event, for example, the Super Combined event consists of one run of super-G and one run of slalom skiing.
The dual slalom event, where racers ski head-to-head, was invented in 1941 and has been a competitive event since 1960. Alpine skiing is contested at the FIS Alpine Ski World Cup, the FIS Alpine World Ski Championships, the Winter Olympics. Para-alpine skiing is contested at the World Para Alpine Skiing Championships and the Winter Paralympics. Speed skiing – Dating from 1898, with official records beginning in 1932 with an 89-mile-per-hour run by Leo Gasperi, this became an FIS discipline in the 1960s, it is contested at the FIS Speed Ski World Cup, was demonstrated at the 1992 Winter Olympics in Albertville. Freestyle skiing – Includes mogul skiing, ski cross, half-pipe, slopestyle; the main freestyle competitions are the FIS Freestyle Skiing World Cup and t
Stepantsminda, is a townlet in the Mtskheta-Mtianeti region of north-eastern Georgia. And ethnographically, the town is part of the Khevi province, it is the center of the Kazbegi Municipality. Stepantsminda was named after a Georgian Orthodox monk named Stephan, who constructed a hermitage at this location on what became the Georgian Military Road; the town is located along the banks of the Terek River, 157 kilometers to the north of Tbilisi at an elevation of 1,740 meters above sea level. Stepantsminda’s climate is moderately humid with dry, cold winters and long and cool summers; the average annual temperature is 4.9 degrees Celsius. January is the coldest month with an average temperature of -5.2 degrees Celsius while July is the warmest month with an average temperature of 14.4 degrees Celsius. The absolute minimum recorded temperature is -34 degrees Celsius and the absolute maximum is 32 degrees Celsius. Stepantsminda’s average annual precipitation is 790 mm.. The town is dominated by large mountains on all sides.
The most notable mountain of the region, Mount Kazbek, lies to the west of town. The second most prominent peak, Mt. Shani, rises to an elevation of 4,451 meters above sea level, 9 kilometers to the east of Stepantsminda; the town is located 10 kilometers to the south of the famous Darial Gorge. According to tradition, Stepantsminda "Saint Stephan", was named so after a Georgian Orthodox monk Stephan, who constructed a hermitage at this location on what became the Georgian Military Highway, it came under the control of a local feudal magnate, the Chopikashvili clan, who were in charge of collecting tolls on travelers in the area in the late 18th century. After the expansion of the Russian Empire into the Kingdom of Georgia in the early 19th century, the people of the region revolted against Russian rule. However, the local lord Gabriel Chopikashvili, son of Kazi-Beg, remained steadfast in his loyalty to Russia and helped to suppress the revolt. In return, he was promoted to officer in the Russian Army.
He adopted the surname Kazbegi, the village under his control was frequently referred to as "Kazbegi". In 1917-1918 Stepantsminda was taken by Germany and The Whites, bar the last who stayed until 1922, the Russians took it from 2008; the name was changed to Kazbegi under Soviet rule in 1925. Gabriel Chopikashvili-Kazbegi's grandson was the famed Georgian writer Alexander Kazbegi, born in this town. In 2006, the town reverted to its original name of Stepantsminda. Horse-riding Paragliding Bike-riding Gergeti Sameba Church Natural mineral waters Mount Kazbek climbing Glaciers Stepantsiminda is known for its scenic location in the Greater Caucasus mountains, is a center for trekkers and mountain climbing. Local attractions include the Kazbegi Museum and Ethnographic Museum in town, the Gergeti Trinity Church outside of town, as well as Mount Kazbegi itself and the alpine meadows and forests of the surrounding Kazbegi Nature Reserve. There is Georgian border crossing point "Larsi" to the Russian Federation 12 kilometers to the North.
The crossing was opened on 1 March 2010. During winter, it is open daily from 7AM till 7PM, during summer from 6AM till 10PM; the customs is multilateral, for all citizens of the world. The cross-border road is in a mountain tunnel, it is not possible to cross the border on foot. In December, 2016 it was announced that AGH holding company plans to build an international airport in Stepantsminda. AGH founded "Aviator" company will provide Air Taxi service that will comprise individual charter flights to any airports in Georgia as well as to neighbouring countries. Mtskheta-Mtianeti "Kazbegi." Georgian Soviet Encyclopedia. Vol. 10, Tbilisi, 1984, pp. 617 Rosen, Roger. Georgia: A Sovereign Country of the Caucasus. Odyssey Publications: Hong Kong, 1999. ISBN 962-217-748-4 Kazbegi Municipality. Mtskheta-Mtianeti Regional Administration website
Bakuriani is a daba and a skiing resort in the Borjomi district of Georgia. It is located on the northern slope of the Trialeti Range, at an elevation of 1,700 meters above sea level; the region around Bakuriani is covered by coniferous forests. The resort is located within the so-called Bakuriani Depression/caldera; the resort is connected with Borjomi by an electrified narrow-gauge railway. The present-day area of the town was built up by lava flows from the nearby Mukhera volcano; the ski area of the resort is split into two separate parts: Kokhta/Kokhta-Mitarbi. Mount Kokhta provides a maximum skiable altitude of 2,269 metres, whereas the highest lift in Didveli reaches 2,702 metres; the climate of Bakuriani is transitional from humid maritime to humid continental. The winters are cold and experience significant snowfall while the summers are warm. Average annual temperature of the town is 4.3 degrees Celsius. The average temperature in January is -7.3 degrees Celsius while the average August temperature is 15 degrees Celsius.
The annual precipitation is 734 mm. The depth of snow from December to March is 64 cm. Bakuriani is home to the Botanical Garden of the Georgian Academy of Sciences, it was the home town of luger Nodar Kumaritashvili, who died during event training on the first day of the 2010 Winter Olympics in Vancouver, British Columbia, Canada. He lived in Bakuriani for much his life, the street he lived on was named in his honor after his death. Georgia's flag-bearing athlete at the opening ceremony, alpine skier Iason Abramashvili resides there; the 37 km Borjomi-Bakuriani railway "Kukushka" uses 912 mm track gauge. A few km south of Bakuriani lies the trajectory of the Baku–Tbilisi–Ceyhan pipeline. List of ski areas and resorts in Europe Samtskhe-Javakheti Bakuriani K-115 www.bakuriani.ge
The Caucasus Mountains are a mountain system at the intersection of Europe and Asia. Stretching between the Black Sea and the Caspian Sea, it surrounds the eponymous Caucasus region and is home to Mount Elbrus, the highest peak in Europe; the Caucasus Mountains include Lesser Caucasus in the south. The Greater Caucasus runs west-northwest to east-southeast, from the Caucasian Natural Reserve in the vicinity of Sochi on the northeastern shore of the Black Sea nearly to Baku on the Caspian Sea; the Lesser Caucasus runs parallel to the Greater about 100 km south. The Greater and Lesser Caucasus ranges are connected by the Likhi Range, to the west and east of the Likhi Range lie the Colchis Plain and the Kur-Araz Lowland; the Meskheti Range is a part of the Lesser Caucasus system. In the southeast the Aras River separates the Lesser Caucasus from the Talysh Mountains which straddle the border of southeastern Azerbaijan and Iran; the Lesser Caucasus and the Armenian Highland constitute the Transcaucasian Highland, which at their western end converge with the highland plateau of Eastern Anatolia in the far north east of Turkey.
The highest peak in the Caucasus range is Mount Elbrus in the Greater Caucasus, which rises to a height of 5,642 metres above sea level. Mountains near Sochi hosted part of the 2014 Winter Olympics. Geologically, the Caucasus Mountains belong to a system that extends from southeastern Europe into Asia; the Greater Caucasus Mountains are composed of Cretaceous and Jurassic rocks with the Paleozoic and Precambrian rocks in the higher regions. Some volcanic formations are found throughout the range. On the other hand, the Lesser Caucasus Mountains are formed predominantly of the Paleogene rocks with a much smaller portion of the Jurassic and Cretaceous rocks; the evolution of the Caucasus began from the Late Triassic to the Late Jurassic during the Cimmerian orogeny at the active margin of the Tethys Ocean while the uplift of the Greater Caucasus is dated to the Miocene during the Alpine orogeny. The Caucasus Mountains formed as the result of a tectonic plate collision between the Arabian plate moving northwards with respect to the Eurasian plate.
As the Tethys Sea was closed and the Arabian Plate collided with the Iranian Plate and was pushed against it and with the clockwise movement of the Eurasian Plate towards the Iranian Plate and their final collision, the Iranian Plate was pressed against the Eurasian Plate. As this happened, the entire rocks, deposited in this basin from the Jurassic to the Miocene were folded to form the Greater Caucasus Mountains; this collision caused the uplift and the Cenozoic volcanic activity in the Lesser Caucasus Mountains. The entire region is subjected to strong earthquakes from this activity. While the Greater Caucasus Mountains have a folded sedimentary structure, the Lesser Caucasus Mountains are of volcanic origin; the Javakheti Volcanic Plateau in Georgia and the surrounding volcanic ranges which extend well into central Armenia are some of the youngest features of the region. Only was the Caucasus a scene for intense volcanic activity: the Armenian highland was flooded by calc-alkaline basalts and andesites in the Pliocene and the highest summits of the Caucasus, the Elbrus, the Kazbek, formed as Pleistocene-Pliocene volcanoes.
The Kazbek is no longer active, but the Elbrus erupted in postglacial times and fumarole activity is registered near its summit. Contemporary seismic activity is a prominent feature of the region, reflecting active faulting and crustal shortening. Clusters of seismicity occur in northern Armenia. Many devastating earthquakes have been documented in historical times, including the Spitak earthquake in December 1988 which destroyed the Gyumri-Vanadzor region of Armenia. Europe's highest mountain is Mount Elbrus 5,642 m in the Caucasus Mountains. Elbrus is 832 m higher than the highest peak in the Alps and western Europe at 4,810 m; the crest of the Caucasus Mountains is taken to define the continental divide between Asia and Europe for the region between the Black and Caspian Seas. The table below lists some of the highest peaks of the Caucasus. With the exception of Shkhara, the heights are taken from Soviet 1:50,000 mapping; the list includes all mountains over 4,500 m height with 300 m prominence.
Mount Ararat in Turkey is just south of the lesser Caucasus. The climate of the Caucasus varies both vertically and horizontally. Temperature decreases as elevation rises. Average annual temperature in Sukhumi, Abkhazia at sea level is 15 °C while on the slopes of Mt. Kazbek at an elevation of 3,700 metres, average annual temperature falls to−6.1 °C. The northern slopes of the Greater Caucasus Mountain Range are 3 °C colder than the southern slopes; the highlands of the Lesser Caucasus Mountains in Armenia and Georgia are marked by sharp temperature contrasts between the summer and winter months due to a more continental climate. Precipitation increases from east to west in most areas. Elevation plays an important role in the Caucasus and mountains receive higher amounts of precipitation than low-lying areas; the northeastern regions and the southern portions of the Lesser Caucasus Mountains are the driest. The absolute minimum annual precipitation is 250 mm in the northeastern Caspian Depression.
Western parts of the Caucasus Mountains are marked by high amounts of precipitation. The southern slopes of the Greater Caucasus Mountain Range receive higher amounts of precipitation than the northern slope
An elevated passenger ropeway, or chairlift, is a type of aerial lift, which consists of a continuously circulating steel cable loop strung between two end terminals and over intermediate towers, carrying a series of chairs. They are the primary onhill transport at most ski areas, but are found at amusement parks, various tourist attractions, in urban transport. Depending on carrier size and loading efficiency, a passenger ropeway can move up to 4000 people per hour, the fastest lifts achieve operating speeds of up to 12 m/s or 43.2 km/h. The two-person double chair, which for many years was the workhorse of the ski industry, can move 1200 people per hour at rope speeds of up to 2.5 m/s. The four person detachable chairlift can transport 2400 people per hour with an average rope speed of 5 m/s; some bi and tri cable elevated ropeways and reversible tramways achieve much greater operating speeds. A chairlift consists of numerous components to provide safe efficient transport. At American ski areas, chairlifts are referred to with a ski industry vernacular.
A one-person lift is a "single", a two-person lift is a "double", a three-person lift a “triple”, four-person lifts are “quads”, a six-person lift is a "six pack". If the lift is a detachable chairlift, it is referred to as a “high-speed” lift, which results in a “high-speed quad” or “high-speed six pack”. Rope speed the speed in feet per minute or meters per second at which the rope moves interval the spacing between carriers, measured either by distance or time capacity the number of passengers the lift transports per hour efficiency the ratio of loaded carriers during peak operation expressed as a percentage of capacity; because fixed grip lifts move faster than detachables at load and unload, misloads are more frequent on fixed grips, can reduce the efficiency as low as 80%. Fixed grip each carrier is fastened to a fixed point on the rope detachable grip each carrier's grip opens and closes during regular operation allowing detachment from the rope and travel for load and unload. Detachable grips allow a greater rope speed to be used twice that of a fixed grip chair, while having slower loading and unloading sections.
See detachable chairlift. The capacity of a lift is constrained by the motive power, the rope speed, the carrier spacing, the vertical displacement, the number of carriers on the rope. Human passengers can load only so until loading efficiency decreases; the rope is the defining characteristic of an elevated passenger ropeway. The rope stretches and contracts as the tension exerted upon it increases and decreases, it bends and flexes as it passes over sheaves and around the bullwheels; the fibre core contains a lubricant which protects the rope from corrosion and allows for smooth flexing operation. The rope must be lubricated to ensure safe operation and long life. Various techniques are used for constructing the rope. Dozens of wires are wound into a strand. Several strands are wound around a textile core, their twist is oriented in the same or opposite direction as the individual wires. Rope is constructed in a linear fashion, must be spliced together before carriers are affixed. Splicing involves unwinding long sections of either end of the rope, winding each strand from opposing ends around the core.
Sections of rope must be removed. Every lift involves at least two terminals and may have intermediate supporting towers. A bullwheel in each terminal redirects the rope, while sheaves on the towers support the rope well above the ground; the number of towers is engineered based on the length and strength of the rope, worst case environmental conditions, the type of terrain traversed. The bullwheel with the prime mover is called the drive bullwheel. Chairlifts are electrically powered with Diesel or gasoline engine backup, sometimes a hand crank tertiary backup. Drive terminals can be located either at the bottom of an installation; the drive terminal is the location of a lift's primary braking system. The service brake is located on the drive shaft before the gearbox; the emergency brake acts directly on the bullwheel. While not technically a brake, an anti-rollback device acts on the bullwheel; this prevents the disastrous situation of runaway reverse operation. The rope must be tensioned to compensate for sag caused by wind load and passenger weight, variations in rope length due to temperature and to maintain friction between the rope and the drive bullwheel.
Tension is provided either by a counterweight system or by hydraulic or pneumatic rams, which adjust the position of the bullwheel carriage to maintain design tension. For most chairlifts, the tension is measured in tons. Either Diesel engines or electric motors can function as prime movers; the power can range from under 7.5 kW for the smallest of lifts, to more than 750 kW for a long, detachable eight-seat up a steep slope. DC electric motors and DC drives are the most common, though AC motors and AC drives are becoming economically competitive for certain smaller chairlift installations. DC drives are less expensive than AC variable-frequency drives and were used