Vertical loop

The generic roller coaster vertical loop, where a section of track causes the riders to complete a 360 degree turn, is the most basic of roller coaster inversions. At the top of the loop, riders are completely inverted.

The vertical loop is not a recent roller coaster innovation. Its origins can be traced back to the 1850s when centrifugal railways were built in France and Great Britain. The rides relied on centripetal forces to hold the car in the loop. One early looping coaster was shut down after an accident. Later attempts to build a looping roller coaster were carried out during the late 19th century with the Flip Flap Railway at Sea Lion Park. The ride was designed with a completely circular loop (rather than the teardrop shape used by many modern looping roller coasters), but caused neck injuries due to the intense G-forces pulled with the tight radius of the loop.

The next attempt at building a looping roller coaster was in 1901 when Edwin Prescott built the Loop the Loop at Coney Island. This ride used the modern teardrop-shaped loop and a steel structure, however more people wanted to watch the attraction, rather than ride. No more roller coasters with vertical loops were built until 1976 when The New Revolution opened at Six Flags Magic Mountain. Its success depended largely on its clothoid-based (rather than circular) loop. The loop became a phenomenon, and many parks hastened to build roller coasters featuring them.

In 2000, a modern looping wooden roller coaster was built, the Son of Beast at Kings Island. Although the ride itself was made of wood, the loop was supported with steel structure. Due to maintenance issues however, the loop was removed at the end of the 2006 season. The loop was not the cause of the ride's issues, but was removed as a precautionary measure. It is the only successful installation of a loop on a wooden roller coaster. Due to an unrelated issue in 2009, Son of Beast was standing but not operating until 2012, where King's Island announced that it would be removed.

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