A roller coaster, or rollercoaster, is a type of amusement ride that employs a form of elevated railroad track designed with tight turns, steep slopes, and sometimes inversions. Passengers ride along the track in open cars, and the rides are often found in amusement parks and theme parks around the world. LaMarcus Adna Thompson obtained one of the first known patents for a roller coaster design in 1885, related to the Switchback Railway that opened a year earlier at Coney Island. The track in a coaster design does not necessarily have to be a complete circuit, as shuttle roller coasters demonstrate. Most roller coasters have multiple cars in which passengers sit and are restrained. Two or more cars hooked together are called a train. Some roller coasters, notably Wild Mouse roller coasters, run with single cars.
The oldest roller coasters are believed to have originated from the so-called \"Russian Mountains\", specially constructed hills of ice located in the area that is now Saint Petersburg, Russia. Built in the 17th century, the slides were built to a height of between 21 and 24 m (70 and 80 feet), had a 50-degree drop, and were reinforced by wooden supports. Later, in 1784, Catherine the Great is said to have constructed a sledding hill in the gardens of her palace at Oranienbaum in St. Petersburg.
The first modern roller coaster, the Promenades Aériennes, opened in Parc Beaujon in Paris on July 8, 1817. It featured wheeled cars securely locked to the track, guide rails to keep them on course, and higher speeds. It spawned half a dozen imitators, but their popularity soon declined.
Using this idea as a basis, LaMarcus Adna Thompson began work on a gravity Switchback Railway that opened at Coney Island in Brooklyn, New York, in 1884. Passengers climbed to the top of a platform and rode a bench-like car down the 600-foot (183 m) track up to the top of another tower where the vehicle was switched to a return track and the passengers took the return trip. This track design was soon replaced with an oval complete circuit. In 1885, Phillip Hinkle introduced the first full-circuit coaster with a lift hill, the Gravity Pleasure Road, which became the most popular attraction at Coney Island. Not to be outdone, in 1886 Thompson patented his design of roller coaster that included dark tunnels with painted scenery. \"Scenic railways\" were soon found in amusement parks across the county.
By 1919, the first underfriction roller coaster had been developed by John Miller. Over the next decade, roller coasters spread to amusement parks around the world and began an era in the industry often referred to as the \"Golden Age\". One of the most well-known from the period is the historical Cyclone that opened at Coney Island in 1927. The onset of the Great Depression in the 1930s, however, significantly impacted the amusement park industry and brought an end to the rapid growth experienced during the Golden Age. This aside, roller coasters were still built with varying success from location to location. In May 1932, the Scene Railway witnessed somewhat of a revival in the UK, including the opening of the roller coaster at Great Yarmouth. Today it is one of only two scenic railways still in operation in the UK.
In 1959, Disneyland introduced a design breakthrough with Matterhorn Bobsleds, the first permanent roller coaster to use a tubular steel track. Designed by Arrow Development, the tubular track was unlike standard rail design on wooden coasters, allowing the track to bend in sharper angles in any direction, leading to the incorporation of loops, corkscrews, and inversion elements into track layouts. A little more than a decade later, the immediate success of The Racer at Kings Island in 1972 sparked a new era of roller coaster enthusiasm, which led to a resurgence across the amusement park industry over the next several decades.
There are several explanations for the name roller coaster. It is said to have originated from an early American design where slides or ramps were fitted with rollers over which a sled would coast. This design was abandoned in favor of fitting the wheels to the sled or other vehicles, but the name endured.
Another explanation is that the phrase originated from a ride located in a roller skating rink in Haverhill, Massachusetts in 1887. A toboggan-like sled was raised to the top of a track which consisted of hundreds of rollers. This Roller Toboggan then took off down gently rolling hills to the floor. The inventors of this ride, Stephen E. Jackman and Byron B. Floyd, claim that they were the first to use the term \"roller coaster\".
In many languages, the name refers to \"Russian mountains\". Contrastingly, in Russian, they are called \"American mountains\". In the Scandinavian languages, the roller coaster is referred as \"mountain-and-valley railway\". German knows the word \"Achterbahn\", stemming from \"Figur-8-Bahn\", like Dutch \"Achtbaan\", relating to the form of the number 8 (\"acht\" in German and also Dutch).
Roller coaster trains are not typically powered. Most are pulled up a lift hill by a chain or cable and released downhill. The potential energy accumulated by the rise in height is transferred to kinetic energy, which is then converted back into potential energy as the train rises up the next hill. Changes in elevation become smaller throughout the track's course, as some mechanical energy is lost to friction and air drag. A properly-designed, outdoor track will result in a train having enough kinetic energy to complete the entire course under a variety of stressful weather conditions.
Not all coasters feature a lift hill, however. A train may also be set into motion by a launch mechanism such as a flywheel, linear induction motor (LIM), linear synchronous motor (LSM), hydraulic launch, or drive tire. Some launched roller coasters are capable of reaching greater speeds using less track when compared to traditional coasters that rely on a conventional lift hill.
A brake run at the end of the circuit is the most common method of stopping a roller coaster train as it returns to the station. One notable exception is a powered roller coaster, which instead of relying on gravity uses one or more motors to propel the trains along the course.
In 2006, NASA announced that it would build a system using principles similar to those of a roller coaster to help astronauts escape the Ares I launch pad in an emergency, although this has since been scrapped along with the rest of the Ares program.
A variety of safety mechanisms protect riders on roller coasters. One of these is the block system. Most large roller coasters have the ability to run two or more trains at once, and the block system prevents these trains from colliding. In this system, the track is divided into two or more sections known as blocks. Only one train is permitted in each block at any given time. There is a section of track at the end of each block where a train can be stopped if necessary, such as preventing dispatch from the station, stopping a lift, or simply applying brakes. Sensors detect when a train passes so that the system's computer is aware of which blocks are occupied. If a train attempts to enter an occupied block, the stopping mechanisms in all blocks are engaged.
Restraints are another critical aspect to roller coaster safety. Generally speaking, roller coasters usually have two different types: Over-the-shoulder-restraints and lap bar restraints. With both, hydraulic and mechanical safety mechanisms are used within the restraints. Mechanical restraints use a system known as a ratchet and pawl. When riding a roller coaster with a ratchet and pawl system, the sound of clicks can be heard when pulling down the restraint. Hydraulic restraints use a piston and cylinder. Unlike mechanical restraints, there is no feeling of physical or sound of clicks from the restraint being locked in place. Most modern day roller coasters have sensors that are used to make sure each restraint is locked. If all the restraints are locked, it will send a signal to the ride computer letting it know that it is clear for dispatch. If all restraints are not locked, the train will not be able to move out of the station until each restraint is locked.
Another key to safety is the programmable logic controller (PLC), an essential component of a roller coaster's computer system. Multiple PLCs work together to detect faults associated with operation and automate decisions to engage various elements (e.g. lift, brakes, etc.). Periodic maintenance and visual inspection by ride engineers are also important to verify that structures and materials are within expected wear tolerances and functioning correctly. Effective operating procedures further enhance safety.
Wheels are a critical part in rollercoaster design. The purpose of wheels is to keep the train on the track and to prevent it from flying off. A majority of roller coaster wheels are made from polyurethane. There are 3 kinds of roller coaster wheels which include road wheels, side friction wheels, and up-stop wheels. Road wheels ride on top of the track. Side friction wheels ride on the side of the track so that the train can move through turns without flying off the side of the track. Up-stop wheels are the wheels that ride below the track and prevent it from lifting off the track.
Roller coasters are statistically very safe when compared to other activities, but despite all the safety measures in place, accidents still occur. The International Association of Amusement Parks and Attractions (IAPPA) reports that a rider has one chance in 15.5 million of being injured on a ride. Also, \"In a typical year, more than 385 million guests enjoyed in excess of 1.7 billion rides at approximately 400 North American fixed-site facilities\". IAPPA is required to report annual ride incidents to the National Safety Council. 59ce067264