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An observation tower is a structure used to view events from a long distance and to create a full 360 degree range of vision to conduct long distance observations . Observation towers are usually at least 20 metres (66 ft) tall and are made from stone, iron, and wood. Many modern towers are also used as TV towers, restaurants, or churches. The towers first appeared in the ancient world, as long ago as the Babylonian Empire.

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82-502: The Spinnaker Tower is a 170-metre (560 ft) landmark observation tower in Portsmouth , England. It is the centrepiece of the redevelopment of Portsmouth Harbour , which was supported by a National Lottery grant. The tower's design was chosen by Portsmouth residents from a selection of three different designs in a 1998 public poll. It has three viewing platforms one on top of the other at heights of 100 m, 105 m and 110 m. The tower

164-506: A hoist , although some pump hydraulic fluid to raise a cylindrical piston like a jack . Elevators are used in agriculture and manufacturing to lift materials. There are various types, like chain and bucket elevators , grain augers , and hay elevators . Modern buildings often have elevators to ensure accessibility, especially where ramps aren't feasible. High-speed elevators are common in skyscrapers . Some elevators can even move horizontally. The earliest known reference to an elevator

246-587: A "Chart for determining the number and size of elevators required for office buildings of a given total occupied floor area". In 1920, Howard B. Cook presented a paper titled "Passenger Elevator Service". This paper marked the first time a member of the elevator industry offered a mathematical means of determining elevator service. His formula determined the round trip time (RTT) by finding the single trip time, doubling it, and adding 10 seconds. In 1923, Bassett Jones published an article titled "The Probable Number of Stops Made by an Elevator". He based his equations on

328-535: A building is at its most busy first thing in the morning; however, in more complicated elevator systems, this model does not work. In 1990, Peters published a paper titled "Lift Traffic Analysis: Formulae for the General Case" in which he developed a new formula which would account for mixed traffic patterns as well as accounting for passenger bunching using Poisson approximation. This new General Analysis equation enabled much more complex systems to be analyzed however

410-553: A concern that the tower might be forced to close. All public buildings in the UK require disabled access under the Disability Discrimination Act 1995 . With the external lift inoperative and only a single internal lift and stairs available as emergency escape routes, disabled people were not allowed to access the tower if they would be unable to use the stairs because a minimum of two escape routes are required by law. This problem

492-545: A cultural attractions group based in York. Continuum also runs five other visitor attractions across the country. The Spinnaker Tower was repainted and rebranded as the "Emirates Spinnaker Tower" from July 2015 following a five-year commercial sponsorship deal with Dubai-based Emirates airline. The Emirates sponsorship deal expired in 2020 and the tower reverted to its original all-white paint scheme and name in April 2021. On 5 May 2023, it

574-426: A deeply grooved pulley , commonly called a sheave in the industry. The weight of the car is balanced by a counterweight . Oftentimes two elevators (or sometimes three) are built so that their cars always move synchronously in opposite directions, and are each other's counterweight. The friction between the ropes and the pulley furnishes the traction which gives this type of elevator its name. Hydraulic elevators use

656-459: A design lifetime of 80 years. Portsmouth's Millennium Tower , as it was originally intended to be named, was a project conceived in 1995 to design a monument to commemorate the Millennium celebrations in the year 2000. It received UK National Lottery funding and was intended to open in late 1999. A choice of three different Millennium Tower designs were presented to the people of Portsmouth for

738-509: A flag pole at its top. Some of these towers are permanently accessible, either free or with the payment of an admission fee. Others are accessible only at certain times, in most cases only with the payment of an admission fee. At these towers the platform is usually open, with some having a restaurant in the basement. There are also towers with a much more extensive use; for example. the observation tower on Rossberg mountains in Reutlingen contains

820-461: A floor at the same time, are usually driven by the same motor. The system increases efficiency in high-rise buildings, and saves space so additional shafts and cars are not required. In 2003, TK Elevator invented a system called TWIN, with two elevator cars independently running in one shaft. In 1901, consulting engineer Charles G. Darrach (1846–1927) proposed the first formula to determine elevator service. In 1908, Reginald P. Bolton published

902-615: A freefall ride to be attached. It opened to the public in June 2018 and featured a bungee jump freefall into a crash net. In 2006, the tower won the RICS Project of the Year award and the RICS Regeneration award. In May 2015, as part of a wider effort to "generate additional revenue by using the advertising potential of council-owned land and other assets", Portsmouth City Council proposed selling

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984-431: A half. Abseiling engineers were called to rescue them. David Greenhalgh said "It is personally very embarrassing as project manager and is very disappointing and upsetting". Some, including the franchise's chief executive, felt it was rather fitting that these particular people had been trapped. The external lift was removed during December 2012. Once open, the tower attracted crowds in excess of expectations, despite only

1066-460: A hotel within its structure. Although most of these towers were initially built before World War I , such structures are still being built, in particular as attractions at horticultural shows . Modern observation towers are in most cases no longer built of brick, but concrete, steel and wood are used as the preferred building materials. Permanent observation towers are also sometimes found in amusement parks , however in parks where each attraction

1148-515: A lighthouse is usually between 10 and 50 metres high, and is almost always open air. Some sports facilities have high buildings with observation decks. This is often the case at ski jumps, as these have a tower and are usually unused in the summer. In addition, there are other sports facilities with observation decks, like the inclined tower of the Montreal Olympic stadium. Access to the platform of nearly all sports facilities with observation deck

1230-534: A more compact system. The IGBT also allowed the development of a small, highly integrated, highly sophisticated all-digital control device, consisting of a high-speed processor, specially customized gate arrays, and a circuit capable of controlling large currents of several kHz. In 2000, the first vacuum elevator was offered commercially in Argentina. Some people argue that elevators began as simple rope or chain hoists (see Traction elevators below). An elevator

1312-805: A new partnership with the Macmillan Cancer Support , with the charity becoming the tower's new sponsor beginning in June. Unlike the previous Emirates sponsorship, the tower will not be repainted or renamed, it will just see the charity's logo on one of the tower's legs and the main sign to the entrance. The deal will allow the charity to hold fundraising events at the tower. Observation tower Observation towers that are used as guard posts or observation posts over an extended period to overlook an area are commonly called watchtowers instead. Similar instances of observation towers are recognised as crow's nests , observatories , viewing platforms , etc. Observation towers are an easily visible sight on

1394-571: A novel tourist attraction which they called the "ascending room", which elevated customers to a considerable height in the center of London, providing a panoramic view. Early, crude steam-driven elevators were refined in the ensuing decade. In 1835, an innovative elevator, the Teagle, was developed by the company Frost and Stutt in England . It was belt-driven and used a counterweight for extra power. In 1845, Neapolitan architect Gaetano Genovese installed

1476-443: A public poll in early 1998. The poll was undertaken by Portsmouth City Council in conjunction with Portsmouth's local newspaper, The News between 11 February 1998 and 23 February 1998. The total number of votes received were 9,476, with 65% of the votes selecting Spinnaker , a design by local architects Hedley Greentree Associates Ltd. Due to political, financial, contractual and construction problems and extra funding requests by

1558-416: A red and white colour scheme—similar to that of local football rivals Southampton F.C. —as part of the rebranding but following a petition with over 10,000 signatures, Portsmouth City Council decided to rethink the change. Portsmouth City Council leader Donna Jones said: "We are working up a new design for the tower [which] will reflect the city’s heritage... I don’t want a tower in the city [that] no one likes

1640-402: A restaurant. The height of these platforms, which can be glassed or open-air depending on the height of the building, where they are most common on the topmost floor. As a rule access usually requires the payment of an admission fee, is possible by elevator only at dedicated opening times. Also numerous water towers have, a usually open-air observation deck opened for public traffic, whose height

1722-428: A rule an elevator is available in these buildings for the visitors of the observation deck, as the observation deck lies usually very highly (mostly within the range between 50 and 200 metres, at some towers also more highly). Many of these towers have also a tower restaurant, which can be designed as revolving restaurant. While tower restaurants for the protection of the restaurant guests from the wind are in closed rooms,

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1804-609: A rule, since these buildings are mostly not higher than 20 metres. Active watch towers are not as a rule accessible to the public, since they usually serve for the monitoring of sensitive ranges. However watch towers can be quite ordered for forest fire monitoring a platform accessible for the public or be used during times without forest fire risk as observation towers. Shut down watch towers can however be easily converted to observation towers. Also some radio towers were so built that they can be used apart from their function as transmitting tower also as observation tower. A condition for this

1886-570: A small cabinet houses the controller. The equipment is otherwise similar to that of a normal traction or hole-less hydraulic elevator. The world's first machine-room-less elevator, the Kone MonoSpace, was introduced in the year 1996, by Kone . Compared to traditional elevators, it: Its disadvantage was that it could be harder, and significantly more dangerous, to service and maintain. Double-decker elevators are traction elevators with cars that have an upper and lower deck. Both decks, which can serve

1968-455: A so-called 'flying chair' built for one of his mistresses at the Château de Versailles in 1743. Ancient and medieval elevators used drive systems based on hoists and windlasses . The invention of a system based on the screw drive was perhaps the most important step in elevator technology since ancient times, leading to the creation of modern passenger elevators. The first screw-drive elevator

2050-572: A successful elevator enterprise in Austria-Hungary. The safety and speed of electric elevators were significantly enhanced by Frank Sprague , who added floor control, automatic operation, acceleration control, and further safety devices. His elevator ran faster and with larger loads than hydraulic or steam elevators. 584 of Sprague's elevators were installed before he sold his company to the Otis Elevator Company in 1895. Sprague also developed

2132-433: A t-antenna for medium wave and stands on insulators. However one notices at the first experimental transmissions that at the tower voltages would arise, which would have unpleasant consequences for visitors and so the tower was grounded by the elevator shaft. However this shifted direction of main beam of transmitter away from actual supply area, the city of Berlin. As before World War II nearly whole radio traffic took place in

2214-420: A variety of factors. Hydraulic elevators are cheaper, but installing cylinders greater than a certain length becomes impractical for very-high lift hoistways. For buildings of much over seven floors, traction elevators must be employed instead. Hydraulic elevators are usually slower than traction elevators. Elevators are a candidate for mass customization . There are economies to be made from mass production of

2296-409: A vertical cylinder, allowing the platform, carrying a heavy load, to be raised and lowered. Counterweights and balances were also used to increase lifting power. Henry Waterman of New York is credited with inventing the "standing rope control" for an elevator in 1850. In 1852, Elisha Otis introduced the safety elevator, which prevented the fall of the cab if the cable broke. He demonstrated it at

2378-669: Is a sufficiently stable construction, which permits a permanent safe visitor entrance without interruption of the transmission services. This is the case for towers for radio services in the UHF/VHF-range the case, not however for most types of radio towers for long and medium wave, why a use of these structures as observation tower is impossible in most cases. That the use of a tower as radio tower for medium wave and observation tower not well fits, showed up in Radio Tower Berlin , which originally carried together with an 80 metres high mast

2460-426: Is applied in high-speed elevators worldwide. The Toshiba company continued research on thyristors for use in inverter control and dramatically enhanced their switching capacity, resulting in the development of insulated gate bipolar transistors (IGBTs) at the end of the 1980s. The IGBT realized increased switching frequency and reduced magnetic noise in the motor, eliminating the need for a filter circuit and allowing

2542-446: Is essentially a platform that is either pulled or pushed up by mechanical means. A modern-day elevator consists of a cab (also called a "cabin", "cage", "carriage" or "car") mounted on a platform within an enclosed space called a shaft or sometimes a "hoistway". In the past, elevator drive mechanisms were powered by steam and water hydraulic pistons or by hand. In a "traction" elevator, cars are pulled up by means of rolling steel ropes over

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2624-436: Is in contrast to the entrance of the church usually only possible under payment an admission fee at the opening times of the church. The height of the observation decks is usually in the range between 20 and 50 metres. The platform is nearly always open-air. Some lighthouses have an observation deck open to the public. Access is usually by stairs. An admission fee is often charged and hours may be limited. The observation deck of

2706-514: Is in the works of the Roman architect Vitruvius , who reported that Archimedes ( c.  287 BC – c.  212 BC ) built his first elevator probably in 236 BC. Sources from later periods mention elevators as cabs on a hemp rope, powered by people or animals. The Roman Colosseum , completed in 80 AD, had roughly 25 elevators that were used for raising animals up to the floor. Each elevator could carry about 600 pounds (270 kg) (roughly

2788-486: Is mostly as the height of older observation towers in the height range between 10 and 50 metres. It can be reached depending upon tower by stairs or by an elevator. Some water towers have also a tower restaurant. Prospect platforms of water towers are nearly only accessible under payment during the opening times, which are different for each tower. Also some church towers possess observation decks. However elevators are only available in rare cases. The entrance of this platform

2870-427: Is not separately paid for, panorama rides are preferred. Watch towers are observation towers, on which persons supervise a larger area. Strictly speaking, control towers also fall into this category, although surveillance from these structures is mostly done in a non-optical way using Radar . Watch towers usually have a closed pulpit to protect the observer against bad weather. Watch towers do not have an elevator as

2952-551: Is only possible during opening times after paying an admission fee. Depending upon the building the access can be done by an elevator and/or a stairway. The platforms can be vitreous or open. The height above ground lies usually between 10 and 50 metres. Fire lookout towers have been used widely in Australia, Canada, and the United States to hoist fire lookout persons to heights where they can identify and report new wildfires. In

3034-571: Is thought to be the first office building with passenger elevators. In 1872, American inventor James Wayland patented a novel method of securing elevator shafts with doors that are automatically opened and closed as the elevator car approaches and leaves them. In 1874, J. W. Meaker patented a method permitting elevator doors to open and close safely. The first electric elevator was built by Werner von Siemens in 1880 in Germany. Inventor Anton Freissler further developed von Siemens' ideas and created

3116-877: The Henninger Turm , a grain silo with tower restaurant and observation deck in Frankfurt, the bell tower of Berlin Olympic stadium , whose platform is accessible by an elevator, the winding tower of the mining industry museum in Bochum, which has an open-air observation deck to which an elevator runs or a wind turbine in Holtriem wind park, which is equipped with a closed platform accessible over stairs. Also aerial tramway support towers, which serve as observation tower (and aerial tramway station), were realized, like Torre Jaume I in Barcelona. Even on

3198-562: The Purbeck Hills , Dorset . The tower represents sails billowing in the wind, a design accomplished using two large, white, sweeping metal arcs, which give the tower its spinnaker sail design. The steelwork was fabricated by Butterley Engineering . At the top is a triple observation deck, providing a 360° view of the city of Portsmouth, the Langstone and Portsmouth harbours, and a viewing distance of 37 kilometres (23 mi). The highest of

3280-498: The UHF / VHF range ( FM sound broadcasting , TV, public rural broadcasting service, and portable radio service). In some cases this usage of the tower is at least as important as its use as an observation tower. Such towers are usually called TV towers or telecommunication towers. Many towers are also equipped with a tower restaurant and allow visitors access via elevators. Also common is the usage of water towers as observation towers. As in

3362-476: The "Flying chair", an elevator ahead of its time in the Royal Palace of Caserta . It was covered with chestnut wood outside and with maple wood inside. It included a light, two benches, and a hand-operated signal, and could be activated from the outside, without any effort by the occupants. Traction was controlled by a motor mechanic utilizing a system of toothed wheels. A safety system was designed to take effect if

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3444-569: The New York exposition in the Crystal Palace in a dramatic, death-defying presentation in 1854, and the first such passenger elevator was installed at 488 Broadway in New York City on 23 March 1857. The first elevator shaft preceded the first elevator by four years. Construction for Peter Cooper 's Cooper Union Foundation building in New York began in 1853. An elevator shaft was included in

3526-417: The United States, there once were over 5,000 fire lookout towers. Areas where birdlife congregates are often associated with bird observation towers to assist with viewing. Hyperboloid structures have a hyperboloid shape that is usually lattice framework and an observation deck on top. There are also some very different observation towers, which don't fit into other categories. Examples for this are

3608-482: The builders Mowlem, construction did not begin until 2001 and was completed in mid-2005. Because of the six-year delay in opening and not having been ready for the Millennium as planned, the tower was renamed Spinnaker Tower instead, the design name it had been called in the 1998 public poll. The overall development project was over budget, with the tower costing £35.6 million alone. Taxpayers were never intended to fund

3690-500: The car does not reach maximum rated speed or acceleration, and added the functionality of express zones. This equation is now referred to as the 'Up peak Calculation' as it uses the assumption that all the passengers are coming into the building from the ground floor (incoming traffic) and that there are no passengers traveling from a higher floor to the ground floor (outgoing traffic) and no passengers traveling from one internal floor to another (interfloor traffic). This model works well if

3772-666: The car passed through them. The first elevator in India was installed at the Raj Bhavan in Kolkata by Otis in 1892. By 1900, completely automated elevators were available, but passengers were reluctant to use them. Their adoption was aided by a 1945 elevator operator strike in New York City, and the addition of an emergency stop button, emergency telephone, and a soothing explanatory automated voice. An inverter-controlled gearless drive system

3854-674: The case of TV towers the visitor will usually reach the observation deck by elevator, which is usually at a lower height above ground The typical height of the observation deck of water towers is 20 metres up to 50 metres, while the typical height of the platform of TV towers is from 80 metres up to 200 metres. Finally, some church towers may have observation decks, albeit often without an elevator. Many other buildings may have towers which allow for observation. In particular prior to World War I rambler associations, and some municipalities, built observation towers on numerous summits. Usually these towers were built of stone, however sometimes wood or iron

3936-485: The components, but each building comes with its own requirements like different number of floors, dimensions of the well and usage patterns. Elevator doors prevent riders from falling into, entering, or tampering with anything in the shaft. The most common configuration is to have two panels that meet in the middle and slide open laterally. These are known as "center-opening". In a cascading telescopic configuration (potentially allowing wider entryways within limited space),

4018-404: The contract with the builders, which at one point would have cost the council more to cancel than to complete. The Spinnaker Tower has suffered from a number of issues since opening, including a malfunctioning external glass lift . During the final construction phase, a protester from the rights group Fathers 4 Justice scaled the tower wearing a high-visibility jacket and unfurling a banner in

4100-458: The cords broke, consisting of a beam pushed outwards by a steel spring. The hydraulic crane was invented by Sir William Armstrong in 1846, primarily for use at the Tyneside docks for loading cargo. They quickly supplanted the earlier steam-driven elevators, exploiting Pascal's law to provide much greater force. A water pump supplied a variable level of water pressure to a plunger encased inside

4182-465: The countryside, as they must rise over trees and other obstacles to ensure clear vision. Older control rooms have often been likened to medieval chambers. The heavy use of stone, iron, and wood in their construction helps to create this illusion. Modern towers frequently have observation decks or terraces with restaurants or on the roof of mountain stations of an aerial ropeway. Frequently observation towers are used also as location of radio services within

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4264-578: The design because Cooper was confident that a safe passenger elevator would soon be invented. The shaft was cylindrical because Cooper thought it was the most efficient design. Otis later designed a special elevator for the building. Peter Ellis , an English architect, installed the first elevators that could be described as paternoster elevators in Oriel Chambers in Liverpool in 1868. The Equitable Life Building , completed in 1870 in New York City,

4346-573: The desire existed to provide these towers with a tower restaurant and an observation deck, in order to make the building of towers more economical via admission fees and increased notability. Several water towers were also built with this in mind, but many have not survived to the modern day. Elevator An elevator ( American English ) or lift ( Commonwealth English ) is a machine that vertically transports people or freight between levels. They are typically powered by electric motors that drive traction cables and counterweight systems such as

4428-409: The doors roll on independent tracks so that while open, they are tucked behind one another, and while closed, they form cascading layers on one side. This can be configured so that two sets of such cascading doors operate like the center opening doors described above, allowing for a very wide elevator cab. In less expensive installations the elevator can also use one large "slab" door: a single panel door

4510-533: The elevator in the late 19th century made taller observation decks possible. Most notably, the Eiffel Tower and the Blackpool Tower were built in this era. Radio towers developed as combined sending and observation tower between 1924 and 1926 in the city of Berlin . After World War II , a great need for tall observation towers arose, due to their dual usage as television and radio transmitters. In large cities,

4592-452: The elevator shaft when the car was not being entered or exited. In 1887, American inventor Alexander Miles of Duluth, Minnesota , patented an elevator with automatic doors that closed off the elevator shaft when the car was not being entered or exited. In 1891, American inventors Joseph Kelly and William L. Woods co-patented a novel way to guard elevator shafts against accident, by way of hatches that would automatically open and close as

4674-482: The equations had now become so complex that it was almost impossible to do manually and it became necessary to use software to run the calculations. The GA formula was extended even further in 1996 to account for double deck elevators. RTT calculations establish an elevator system's handling capacity by using a set of repeatable calculations which, for a given set of inputs, always produce the same answer. It works well for simple systems; but as systems get more complex,

4756-491: The first book devoted to this subject, Elevator Service . The summation of his work was a massive fold-out chart (placed at the back of his book) that allowed users to determine the number of express and local elevators needed for a given building to meet a desired interval of service. In 1912, commercial engineer Edmund F. Tweedy and electrical engineer Arthur Williams co-authored a book titled Commercial Engineering for Central Stations . He followed Bolton's lead and developed

4838-802: The idea and technology for multiple elevators in a single shaft. In 1871, when hydraulic power was a well established technology, Edward B. Ellington founded Wharves and Warehouses Steam Power and Hydraulic Pressure Company, which became the London Hydraulic Power Company in 1883. It constructed a network of high-pressure mains on both sides of the Thames which ultimately extended 184 miles (296 km) and powered some 8,000 machines, predominantly elevators and cranes. Schuyler Wheeler patented his electric elevator design in 1883. In 1884, American inventor D. Humphreys of Norfolk, Virginia , patented an elevator with automatic doors that closed off

4920-469: The internal lift working, with more than 600,000 people visiting it in the first year. It is one of a number of observation towers around the world that have become popular, including Vancouver 's Harbour Centre , Toronto's CN Tower , Blackpool 's Tower , New York City's One World Trade Center (as well as the original Twin Towers ) and Shanghai's Oriental Pearl Tower . In June 2006, the local press raised

5002-457: The introduction of steel beam construction, worked together to provide the passenger and freight elevators in use today. Starting in coal mines, elevators in the mid-19th century operated with steam power , and were used for moving goods in bulk in mines and factories. These devices were soon applied to a diverse set of purposes. In 1823, Burton and Homer, two architects in London , built and operated

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5084-464: The long -, medium and shortwave range, first after World War II with introduction of radio services in UHF/VHF-range required towers only acting as antenna carriers, radio towers with observation decks built. For this the closed reinforced concrete construction way was nearly always used. Radio towers with observation decks often serve for TV transmission or for radio relay link services and are called therefore usually TV tower or telecommunication tower. As

5166-498: The look of." The new design, unveiled on 19 June 2015, featured a blue, gold and white colour scheme. Tim Clark , President and CEO of Emirates said: "We listened to the feedback and worked with the council to adapt the designs in order to create something that Portsmouth residents will be proud of." In April 2021 the tower was repainted its original all-white colour, as the five year sponsorship deal with Emirates had ended on 30 June 2020. On 5 May 2023, Portsmouth City Council announced

5248-457: The principles of hydraulics (in the sense of hydraulic power ) to pressurize an above-ground or in-ground piston to raise and lower the car (see Hydraulic elevators below). Roped hydraulics use a combination of both ropes and hydraulic power to raise and lower cars. Recent innovations include permanent magnet motors, machine room-less rail mounted gearless machines, and microprocessor controls. The technology used in new installations depends on

5330-492: The process. Another incident happened a year later when a base jumper managed to get past site security and jumped off the Tower; he quickly ran off site after parachuting down. The tower was dedicated on 16 October 2005 and opened two days later. On opening day, the tower's project manager , David Greenhalgh, and representatives of Mowlem and Maspero were stranded in its malfunctioning external lift (built by Maspero) for an hour and

5412-417: The prospect platform can be open or in a closed room. An open platform is more favourable for photographing, since no reflexes at the disk arise, while closed platforms are for many visitors more pleasant. Prospect outlooks on TV towers are opened only at certain times and their entrance is possible only under payment of an admission fee. Also numerous highrise buildings have observation decks , sometimes even

5494-505: The pylons of suspension bridges were already observation decks installed, as the example of Nový Most in Bratislava shows. A very unusual observation tower is Pont basculant de la Seyne-sur-Mer . It was once a bascule bridge, now permanently put upright and used as observation tower. In Germany, observation towers first appeared on the countryside at the end of the 18th century. These early towers were often built by wealthy aristocrats . It

5576-412: The theory of probabilities and found a reasonably accurate method of calculating the average stop count. The equation in this article assumed a consistent population on every floor. He went on to write an updated version of his equations in 1926 which accounted for variable population on each floor. Jones credited David Lindquist for the development of the equation but provides no indication as to when it

5658-450: The three observation platforms, the Sky Deck, has only a wire mesh roof, so visitors are open to the elements. The windows extend above head height, so it is not possible to get a view unobstructed by glass. A glass floor is located on the first viewing deck at 100 metres above sea level. It has three viewing platforms one on top of the other at heights of 100 m, 105 m and 110 m. The tower has

5740-541: The tower to be renamed as the Emirates Spinnaker Tower. On 5 June 2015, the city council confirmed that Emirates had been secured as the sponsor. Councillor Luke Stubbs said: "It's clearly a very good deal for the city and shows the benefit that Portsmouth is deriving from the America’s Cup... This also associates Portsmouth with a global brand and that can only be a good thing." The tower was to be repainted in

5822-413: The tower's naming rights to a commercial sponsor. The proposed sponsorship deal would include the naming rights for the tower for at least five years, repainting and rebranding the tower in the sponsor's choice of colours and logos and new signage to be installed "no later than July 17" ahead of the 2015 America's Cup World Series . Dubai-based airline Emirates was reported to be the favoured sponsor, with

5904-545: The tower, but Portsmouth City Council eventually contributed £11.1 million towards construction. In March 2004, Portsmouth Council's former leader Cllr Leo Madden resigned as leader of the Labour Group on the council after a highly critical report of the council's handling of the project and its failure to exploit revenue opportunities, such as the Millennium. Barry Smith, the project's legal advisor, also retired after being suspended on full pay, mostly because of controversy over

5986-501: The weight of two lions) 23 feet (7.0 m) up when powered by up to eight men. In 1000, the Book of Secrets by Ibn Khalaf al-Muradi in Islamic Spain described the use of an elevator-like lifting device to raise a large battering ram to destroy a fortress. In the 17th century, prototypes of elevators were installed in the palace buildings of England and France. Louis XV of France had

6068-403: The width of the doorway that opens to the left or right laterally. These are known as "single slide" doors. Some buildings have elevators with the single door on the shaftway, and double cascading doors on the cab. Elevators that do not require separate machine rooms are designed so that most of their power and control components fit within the hoistway (the shaft containing the elevator car), and

6150-657: Was also used. At nearly all these towers access to the observation deck , usually at a height of between 5 and 40 metres, is only possible by way of stairs. Most of these towers are used only for tourism, however some of these towers might also be used, at times of high forest fire risk, as fire observation posts or in times of war as military observation posts with anti-aircraft positions placed beside it. Further uses were not intended at most of these buildings, although some of these towers today now carry antennas for police/fire engine radios, portable radio or low power FM- and TV-transmitters. Older observation towers frequently have

6232-663: Was announced that Macmillan Cancer Support would become the tower's new sponsor beginning in June. At a height of 560 feet (170 m), the tower is one of the tallest accessible structures in the United Kingdom outside London. The tower is visible around Portsmouth, changing the horizon of the area. It can be seen from the Isle of Wight , the Manhood Peninsula , Highdown Gardens and Cissbury Ring in Worthing and Nine Barrow Down in

6314-540: Was built by Ivan Kulibin and installed in the Winter Palace in 1793, although there may have been an earlier design by Leonardo da Vinci . Several years later, another of Kulibin's elevators was installed in the Arkhangelskoye near Moscow . The development of elevators was led by the need for movement of raw materials, including coal and lumber , from hillsides. The technology developed by these industries, and

6396-455: Was designed by local firm HGP Architects and engineering consultants Scott Wilson and built by Mowlem with steelwork by Butterley Engineering . The Spinnaker Tower reflects Portsmouth's maritime history through its design and is named after a spinnaker , a type of sail that balloons outward. The tower was opened on 18 October 2005. The tower is owned by Portsmouth City Council and is operationally managed by Continuum Leading Attractions,

6478-448: Was first proposed. Although the equations were there, elevator traffic analysis was still a very specialist task that could only be done by world experts. That was until 1967 when Strakosch wrote an eight step method for finding the efficiency of a system in "Vertical transportation: Elevators and Escalators". In 1975, Barney and Dos Santos developed and published the "Round Trip Time (RTT) formula", which followed Strakosch's work. This

6560-510: Was not until the mid-19th century that citizens took control of the construction of such towers. In Austria and Switzerland many observation towers were established by alpine and tourist associations, and continue to be cared for by them. In the Waldigen Mountains , many citizen committees were active. Because of the long reign of emperor Franz Joseph , many observation decks carry the name "anniversary observation platform". The invention of

6642-509: Was rectified by investing in an evacuation chair and training staff to use it. In the event of evacuation, should the internal lift be inoperable, those unable to navigate the 570 steps can use the evacuation chair. The Spinnaker Tower, being a landmark of southern England, features in the title sequence of the BBC South Today news programme. It also features on ITV News. In June 2009, the tower's operators succeeded in gaining permission for

6724-492: Was the first formulized mathematical model and is the simplest form that is still used by traffic analyzers today. Modification and improvements have been made to this equation over the years, most significantly in 2000 when Peters published "Improvements to the Up Peak Round Trip Time Calculation" which improved the accuracy of the flight time calculation, making allowances for short elevator journeys when

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