There are several types of launch coasters but the most common is an LSM (linear synchronous motor) launching system. These launches use powerful magnetic fields to push and pull the train along the track without any physical contact. For this post I will be using Full Throttle from Six Flags Magic Mountain as an example.
How does it work?
An LSM, or Linear Synchronous Motor, is a set of motorized magnets that pull the train through the launching area of the ride. An LSM consists of three things: Stators, thyristors, and a magnetic yoke.
Stators (image) are the main form of the launching system, they are the magnets that are being powered to launch the train. Stators can also slow and stop a train, this makes any area where stators are located a block zone.
Thyristors are the cables connected to the stators, they bring power to the stators during the launch.
Magnetic Yokes are magnets located on the bottom of the train. These magnets are the opposite polarity of the stators. When the stators become powered they pull the magnets in the magnetic yoke forward causing the launch.
Other Types of Launch Coasters
Hydraulic Launch Coaster
One of the most well-known types of launch systems is the hydraulic launch. This system uses pressurized hydraulic fluid to build up energy and then release it all at once to propel the train forward. Here’s how it works: hydraulic pumps fill a set of accumulators (which are like high-pressure tanks) with hydraulic fluid. These accumulators compress nitrogen gas inside, storing a lot of energy. When the launch is triggered, valves open and the pressurized fluid spins a large winch drum connected to a cable. The cable pulls a catch car, which is attached to the bottom of the train. When the catch car reaches the end of the launch track, it disconnects, and the train continues on its own.
Hydraulic launches can create extremely fast accelerations. For example, Top Thrill Dragster and Kingda Ka both used this system to launch trains to over 100 mph in just a few seconds. However, hydraulic launches are complex and require a lot of maintenance due to the pressure systems, valves, and cables involved.
Pneumatic Launch Coaster
A pneumatic launch works similarly to a hydraulic one, but instead of hydraulic fluid, it uses compressed air. Air compressors fill large tanks, and when the launch starts, that air is rapidly released into cylinders that push a piston forward. The piston is connected to a catch car that pulls the train down the track. This system allows for quick and powerful launches, though it’s not as smooth as LSM or hydraulic systems.
A good example is Dodonpa (now Do-Dodonpa) at Fuji-Q Highland in Japan, which once held the record for the fastest acceleration in the world. Pneumatic systems are less common today because they’re very loud and can be harder to control precisely compared to magnetic systems.
Flywheel Launch Coaster
A flywheel launch uses a giant spinning wheel (the flywheel) to store energy as rotational momentum. When the launch is triggered, the flywheel is quickly connected to a cable system using a clutch, and its stored rotational energy pulls the train forward through a cable attached to the catch car.
This type of launch is fast and powerful but requires time between launches to spin the flywheel back up to speed. A classic example is Montezooma’s Revenge at Knott’s Berry Farm, which uses a flywheel to launch the train out of the station and then backward through the loop later in the ride.