A roller coaster inversion is a roller coaster element in which the track turns riders upside-down and then returns them to an upright position. Early forms of inversions were circular in nature and date back to 1848 on the Centrifugal railway in Paris. These vertical loops produced massive g-force that was often dangerous to riders. As a result, the element eventually became non-existent with the last rides to feature the looping inversions being dismantled during the Great Depression. In 1975, designers from Arrow Development created the corkscrew, reviving interest in the inversion during the modern age of steel roller coasters. Elements have since evolved from simple corkscrews and vertical loops to more complex inversions such as Immelmann loops and cobra rolls. The Smiler at Alton Towers holds the world record for the number of inversions on a roller coaster with 14.
Roller coaster inversion in the context of Centrifugal railway
Centrifugal Railway was the name of a number of early looping roller coasters that were built in Western Europe in the middle of the 19th century. These rides were very similar in their basic design to many modern-day shuttle roller coasters (i.e., they did not make a complete circuit), but with only one lift hill and no launch. A single roller coaster car would ascend to the peak on the coaster before descending rapidly down the same hill and then passing through the central loop with enough speed to remain on the track at the top of the loop. The size of these centrifugal railways differed; some were purported to have vertical loops of a mere 2 metres (6.6 ft), while others were estimated to be 12 metres (39 ft) (although, as described below, early coaster designers were prone to cases of gross exaggeration).
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