Modern roller coaster launch systems have replaced traditional chain lift hills as the primary way to gain speed on the most thrilling rides. Where a chain lift takes 30 seconds or more to reach the top of a 200-foot hill, modern launches accelerate trains from 0 to 70 mph in less than three seconds. The technology behind these launches falls into several distinct categories, each with engineering trade-offs that affect both the ride sensation and the park’s maintenance budget. Understanding the different systems explains why your favorite launched coaster feels the way it does.
Linear Synchronous Motors (LSM)
LSM launches use a series of electromagnets along the track that precisely control train acceleration. The magnets pull on permanent magnets fixed to the train, with computer-timed pulses delivering smooth, sustained acceleration. LSM systems can also be reversed for braking, which is why launches like Universal’s VelociCoaster can pulse trains forward and backward through the launch zone.
The advantage is precise control and minimal mechanical wear. The disadvantage is high energy demand and complex control systems that require specialized maintenance.
According to technical documentation on LSM systems, the technology was first applied to roller coasters in the late 1990s and has since become dominant for new launched installations.
Linear Induction Motors (LIM)
LIM systems work on similar electromagnetic principles but generate force by inducing currents in a metal fin attached to the train, rather than acting on permanent magnets. LIM launches typically deliver shorter, more aggressive acceleration than LSM, producing the punchy “kick” that older launches like California Screamin’ (now Incredicoaster) at Disney California Adventure deliver.
LIM systems are simpler and cheaper than LSM but less efficient and harder to control precisely.
For more on how launch G-forces affect your body, our breakdown of how roller coaster G-forces affect your body explains the physiological response to sudden acceleration.
Hydraulic Launches
Intamin’s hydraulic launches power coasters like Top Thrill 2 (formerly Top Thrill Dragster) and Kingda Ka. The system uses a massive cable winch driven by hydraulic motors, capable of accelerating trains to 120 mph in under 4 seconds. The brutal acceleration produces some of the most intense launch sensations in the industry.
The downside is reliability. Hydraulic launch systems have suffered notable mechanical failures, including the cable incident that closed Top Thrill Dragster from 2021 until its 2024 rebuild as Top Thrill 2.
Compressed Air Launches
Premier Rides’ air launch system uses a piston driven by compressed air to accelerate trains. The technology produces extremely fast launches with low maintenance compared to hydraulic systems, powering rides like Maverick at Cedar Point and Stealth at Thorpe Park in the UK.
Air launches typically deliver faster initial acceleration than electromagnetic systems but lower top speeds.
Industry coverage at Coaster101 notes that air launches have become increasingly favored for mid-sized installations because they balance thrill with maintenance costs better than hydraulic alternatives.
Friction Wheel Launches
The original launch system used spinning rubber wheels to grip and accelerate trains. While dated by modern standards, friction wheel launches still operate on rides like Rock ‘n’ Roller Coaster at Disney’s Hollywood Studios. The systems are simple and reliable but limited to relatively modest top speeds (60 mph or less).
Why Launch Systems Matter to Riders
The launch system on your favorite coaster determines not just top speed but the character of the experience — the smoothness of acceleration, the punch of the initial kick, and even the sound the ride makes. As LSM systems become more affordable, expect them to displace older technologies on most new installations through the 2030s.
For more on how launches fit into the broader coaster category landscape, our piece on every type of roller coaster explained covers how launches differ from chain lifts, gravity drops, and other ride classifications.
Frequently Asked Questions
What is the fastest launch system?
Hydraulic launches like Intamin’s system on Top Thrill 2 deliver the fastest absolute speeds, exceeding 120 mph on the most extreme installations.
How does an LSM launch work?
Linear Synchronous Motors use a series of electromagnets along the track that act on permanent magnets fixed to the train, providing precise, computer-controlled acceleration.
Are launched coasters safer than chain lifts?
Both are extremely safe when properly maintained. Launches have different failure modes than chain lifts but no significantly higher accident rate.
Why do some launches go backwards?
LSM systems are reversible, allowing rides like VelociCoaster to pulse trains forward and backward. Hydraulic and friction wheel launches generally cannot reverse direction.
How long does a typical coaster launch last?
Most launches last 2 to 5 seconds depending on target speed, with hydraulic systems delivering the shortest, most aggressive acceleration profiles.