Launched roller coaster

The launched roller coaster is a modern form of roller coaster which has increased in use in the last decade. In place of a traditional chain lift, the launched coaster initiates a ride with high amounts of acceleration via one or a series of Linear Induction Motors (LIM), Linear Synchronous Motors (LSM), catapults, or other mechanisms employing hydraulic or pneumatic power. These are some of the fastest rides in the world.

Launched coasters mainly feature improved speed, and capability to accommodate more "thrilling" layouts. These coasters, however, can be less reliable than traditional chain-lifted coasters, and are considered to require heavier maintenance. The first launched roller coaster was Montezuma's Revenge at Knotts Berry Farm in Southern California.

Linear Induction Motor (LIM) and Linear Synchronous Motor (LSM) coasters use propulsion via electromagnets, which utilize large amounts of electricity to propel the coaster train along its track into the ride elements (e.g. inversions, twists, turns and short drops). Seven design companies managing these types of rides are Vekoma Industries, Intamin, Gerstlauer, Premier Rides, Maurer Söhne, Zierer, MACK Rides and just recently, Bolliger and Mabillard added Thunderbird at Holiday World which is their (meaning Holiday World and Bolliger and Mabillard) first ever launched coaster.

Electricity is transferred into a motor so that it controls the speed at which it will urge the car forward. LIMs are mainly used in Premier Rides roller coasters and Intamin impulse coasters. However, LIMs are also used for transport systems and the Tomorrowland Transit Authority in the Magic Kingdom for low acceleration, unlike what most roller coasters use for high acceleration.

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