The Chain Lift Hill is used to transport the roller coaster train to an elevated point or peak in the track. Upon reaching the peak, the train is then propelled by gravity coasting through the circuit using its own momentum. Chain Lift Hills are the traditional method utilised for propelling roller coasters but in more recent years a number of new methods have been implemented including the popular powered launch.
How Chain Lift Hills Work
Chain lift hills utilise a long, continuous chain which travels through a steel trough in the centre of the track. The chain is normally powered by one or more motors which are positioned underneath the lift hill. Mounted onto the underside the roller coaster train is a heavy piece of metal called a chain dog. The chain dog is engaged by the chain and the roller coaster train is pulled up the lift hill. At the crest of the lift hill, the chain wraps around a gear wheel where it begins its return to the bottom of the lift (running underneath the track). The roller coaster train is continually pulled along until gravity takes over and it accelerates downhill. The spring-loaded chain and anti-rollback dogs will disengage themselves as this occurs.
Anti-Rollback Safety Device
The familiar Click-Clack sound that a roller coaster makes as the train ascends the lift hill is the Anti-Rollback Safety Device.
Roller coaster trains are fitted with anti-rollback “dogs” which are essentially heavy-duty pieces of metal which fall and rest in each groove of the anti-rollback device on the track as the trains ascend the lift-hill. This makes the familiar sound and allows the train to go upwards only, effectively preventing the train from rolling back down the hill should it ever encounter a power failure or broken chain.
Vertical Lift Hill
A recent new development found on roller coasters manufactured by Gerstlauer is the Vertical lift hill. Utilising a similar mechanism to a regular Chain Lift Hill, rather than transporting the roller coaster train to an elevated point or peak in the track via a banked incline, a Vertical Chain Lift Hill goes straight up. In addition to providing riders with additional thrills, Vertical Chain Lift Hills are also ideal when space is at a premium, thanks to the limited amount of space that they require.
The Ultimate at Lightwater Valley
On occasions, roller coasters may have more than one chain lift hill, which helps to increase the duration of the ride and the area covered. The Ultimate at Lightwater Valley is an example of this, using its first lift hill to gain the energy required to propel the roller coaster train to the far end of the park. The ride then uses a second lift hill to provide the energy to bring the roller coaster back again.