Roller Coaster: The Great Fairground Attraction

How They Move

Like a passenger train, a roller coaster consists of a series of connected cars that move along a track. Unlike a passenger train, however, it has no engine or power source of its own. For most of the ride, it is moved only by the forces of inertia and gravity. Energy is applied only at the very beginning of the ride, when the coaster train is pulled up the lift hill.

The traditional lifting mechanism consists of a long chain running up the hill beneath the track. The chain is fastened into a loop, which is wound around a gear at the top of the hill and another gear at the bottom.

The gear at the bottom of the hill is turned by a motor. This moves the chain continuously up the hill like a long conveyor belt. The coaster cars grip the chain, which pulls them to the top of the hill. At the summit, the train is released and begins its descent.

The purpose of this initial ascent is to build up a reservoir of potential energy. Put simply, the higher the coaster rises into the air, the greater the distance over which gravity can pull it down.

As the train begins to coast down the hill, this potential energy is converted into kinetic energy, or energy of motion, and the train accelerates. At the bottom of the hill, the kinetic energy reaches its maximum and propels the train up the second hill, once again increasing its level of potential energy.

In this way, the track continually converts energy from kinetic energy to potential energy and back again. This fluctuation in acceleration is what makes roller coasters so exciting. At the most basic level, a roller coaster is simply a machine that uses gravity and inertia to send a train along a winding track.

Coasting Through History

Roller coasters have a long and fascinating history. Their direct ancestors were ice slides that were popular in Russia during the 16th and 17th centuries. They consisted of long, steep wooden slides covered with ice.

Riders climbed a ladder or a set of stairs to the top of the slide, which could be as high as twenty-one metres. At the top, they climbed into sleds made from wood or blocks of ice and travelled rapidly down the slope. At the bottom of the slide, the sleds landed in a pile of sand.

The idea appears to have been imported into France. During most of the year, the warmer climate melted the ice, so the French began constructing waxed slides instead.

To help the sleds travel down these slides, wheels were added. In 1817, for the first time, a train was attached to the track. The French continued to develop the idea, creating more complicated track layouts with multiple cars and many different twists and turns.

The first American roller coaster was constructed in the mountains of Pennsylvania during the mid-19th century. It was originally intended to provide a convenient way of transporting coal to a railway twenty-nine kilometres down the mountain.

When the track was first constructed, workers at the bottom of the mountain attached each empty cart to a team of mules, which dragged it back to the top. The mules were eventually replaced by steam engines in order to make the system more efficient.

Soon after these improvements were introduced, the railway company constructed a new tunnel that brought freight trains much closer to the coal mine. As the original track was no longer required for transporting coal, it was converted into a "scenic tour".

For one dollar, tourists could enjoy a leisurely journey to the top of the mountain, followed by a wild and uneven ride directly down the slope. The attraction soon became a great success and drew thousands of tourists every year.

Scenic rides of this kind continued to prosper and were joined by wooden roller coasters similar to those familiar today. These coasters became the main attractions at popular amusement parks throughout the United States, including the numerous parks at Coney Island in New York.

By the 1920s, roller coasters were extremely popular, with approximately 2,000 rides operating across the country.

Following the Great Depression, roller-coaster production began to decline in the early 1930s. However, a second boom during the 1970s and the beginning of the 1980s revitalised the amusement-park industry and introduced numerous innovative tubular-steel roller coasters.

This was followed by a decline in interest throughout the remainder of the 1980s. Since the early 1990s, however, the amusement-park industry has experienced another roller-coaster boom.

New launching methods and other technological developments have provided designers with a much wider range of possibilities. On some modern rides, passengers feel as though they are flying. Over the next few years, many faster, taller and more twisted rides can be expected to appear in amusement parks throughout the world.