Launched roller coaster

The launched roller coaster is a type of roller coaster that initiates a ride with high amounts of acceleration via one or a series of linear induction motors (LIM), linear synchronous motors (LSM), catapults, tires, chains, or other mechanisms employing hydraulic or pneumatic power, along a launch track.

These launch systems transfer electricity through a motor on the roller coaster's track so that it controls the speed at which it will urge the cars and train either forward or backward on a segment.

However, LIMs can also be used for general transport, such as the Tomorrowland Transit Authority PeopleMover in Magic Kingdom or monorail and maglev trains.

Hydraulic-launched roller coasters, pioneered by Swiss manufacturer Intamin, give the riders greater acceleration with improved smoothness over the electromagnetic and catapult launch mechanisms.

At launch, the fluid under pressure from the accumulators is used to drive a number of hydraulic motors (commonly 16 or 32), which spin a large winch drum that rewinds a cable attached to the lead car of the train, called the catch-car, in a matter of seconds.

Once the pusher connects, the anti-rollback braking system drops beneath the track, giving the train the green light to be launched.

The world's tallest roller coaster, Kingda Ka at Six Flags Great Adventure, was capable of reaching 128 mph (206 km/h) in 3.5 seconds.

The fastest roller coaster in the world, Formula Rossa, reaches 149 mph (240 km/h) in 4 seconds using the hydraulic method.

Accelerator Coasters manufactured by Intamin commonly place a top hat element after the launch, which is a hill in the shape of a tower with a 90-degree ascent and 90-degree drop.

Another manufacturer, Vekoma, began producing hydraulic-launched coasters in 2004 with the opening of Booster Bike at Toverland in the Netherlands, reaching speeds up to 47 mph (76 km/h).