Roller coasters have provided some of the biggest challenges for structural engineers since their invention in the last century. Steel and timber structures supporting twisting and plunging rides have become increasingly complex over the last 100 years as amusement park owners have battled to stay ahead of their competitors.
Civil engineer David Bennett's recently published book Roller Coaster* reveals that today's rides have come a long way since bored Russians developed toboggan-style hillside ice slides in 15th century St Petersburg.
The book covers the whole gamut of rides from the first gravity railway at Mauch Chunk Pennsylvania right up to Blackpool's Pepsi Max Big One and Japan's Fujiyama, reputedly the world's tallest steel roller coaster.
Roller coaster design really began to evolve during the late 19th and early 20th centuries as increasingly spectacular wheeled rides began to capture the public imagination.
Many 19th century roller coasters had been popular if at times rather pedestrian attractions. Cars on the fastest ones travelled at speeds up to 48km/h, although some were as slow as 9.6km/h. But a new generation of ride allowed designers to produce rides with drops of between 18m and 30m capable of pushing cars along at an exhilarating 88km/h.
'Under-friction wheels', which stopped coaster cars from lifting off their tracks while allowing them to keep moving at speed, enabled designers to develop the first mega rides at the turn of the century.
Bigger, more frightening rides followed, pushing designs to new limits ultimately leading to the introduction of the first steel supported roller coasters at Disneyland in California at the end of the 1950s.
Although serious accidents on roller coasters are rare, much of the mystique of riding them lies in the feeling the riders are dicing with death. Indeed, Roller Coaster includes an account of one ride where the owners let it be known that a nurse was always on duty.
In fact few serious accidents appear to have been caused by structural failures induced by fast moving cars.
Whiplash injuries to several passengers on an early loop the loop ride at Coney Island forced its premature closure, but fatalities have been rare. The man who died on the Bobs at Riverview Park Illinois fell off after standing up as his car reached the top of the ride. He was struck by a 'stay seated' sign.
Roller coaster design took a second leap forward in the mid 20th century when the first steel rides began to challenge the dominance of timber framed structures.
The first steel ride was developed by Karl Bacon and Walt Disney Imagineering in the 1950s for the original Disneyland in Los Angeles. Steel has pushed roller coaster technology to new limits, taking the rides away from their rattly, 'runaway train' roots. Instead modern steel structures produce a sensation of smooth, rapid low level flight and give designers the flexibility to introduce spirals and complex multi radius curves.
*Published by Atrium Press. Tel: (0171) 637 3225, price £14.99