Roller Coasters Are Safe; Tech Makes Them Safer.
Roller coasters are the staple of the American amusement park. They are being built taller and faster than ever before these days, and all the while are tremendously safe. In fact, you are millions of times more likely to die in a car accident on your way to an amusement park than die due to a roller coaster accident.
So how is that? How do roller coasters work and remain so safe consistently? Well for starters, it could be argued pretty easily that amusement parks are in the business of safety. If there is even the slightest rumor that a park’s coasters are unsafe, it will pretty much kill the reputation of the park and possible kill the business. So maintaining that status of extreme safety is arguably the number one priority for an amusement park.
This need for parks to have safe rides fuels most of why they are so safe, as typically every coaster is thoroughly examined every day prior to the park opening. But to get into how technology helps make coasters run safely, I need to go over the basics of how coasters work.
Roller coasters are powered by physics and Newton’s Law of Motion. The traditional coaster starts with a chain-hill lift pulling the coaster train up to the top of its first (and tallest) drop. Heading up the first hill, the coaster begins to build potential energy, meaning the higher the coaster goes the longer distance gravity can pull the coaster train down. As the train descends down the first drop, gravity pulls the train downward faster and faster, and that potential energy is turned into kinetic energy, which is the energy that pushes the train along the rest of the coaster’s track.
While some coasters use other methods to power the kinetic energy of the coaster (electro-magnets and air pressure are some examples), the traditional coaster gets 100% of its power to run its entire track from the kinetic energy it obtains from the first drop. This means that there is no point on the roller coaster that is higher than that first drop, as there will never be enough kinetic energy to exceed the height of the first drop; something us RollerCoaster Tycoon babies learned the hard way.
After the first drop, a coaster is run by momentum and G-Forces. Its track is designed to have a good balance of thrill, without making the Gs too high. Newton’s Laws of Motion states that objects in motion tend to stay in motion and objects at rest tend to stay at rest. This is why you get pushed back into your seat when the train accelerates, you get pushed laterally when the train turns, and why you lift out of your seat over a hill and get pushed into your seat at the bottom of a drop. Too many Gs on a human can make them either pass-out or die, so it's extremely important that the design of the coaster doesn’t create Gs too dangerous for humans to undergo.
So now that we know how roller coasters work, how are they safe? What is done to make them so safe during such violent movement?
Plenty of reasons, but for starters you have the wheel-assembly. The first and probably most important issue with roller coaster safety would be making sure that the train doesn’t jump the tracks and crash during the ride. Coaster train wheel-assemblies have three sets of wheels, one on top, and one on the side to maintain smooth movement down the track. They also include what’s called underfriction wheels that run on the underside of the track and pin the train on the tracks preventing derailment during the ride’s violent motion.
The coaster’s harnesses and restraints are usually power by pneumatics (pressurized air; very powerful) or hydraulics (pressurized water; insanely powerful) to ensure the motion of the coaster and its Gs, as well as the weight of the rider, cannot force the restraint open. Of course as a safety measure, they usually also contain seatbelts or clasps as a failsafe in the event something goes wrong during the ride.
Lifthills and coaster train cars all have anti-rollback features that have a saw-tooth shaped strip of metal running alongside the chain lift, and the train cars all have “dogs”, or strong pieces of metal that slide over the saw-tooth strip allowing the train to freely move up the hill, but should power failure occur or the lift chain breaks, the “dog” will dig into the strip and stop the train car from rolling back into the station. It’s this safety feature that makes the “clack-clack” noise synonymous with riding the lift of a roller coaster.
Block zones are also used to prevent coaster trains from colliding if they are running more than one train at the same time. This is done by designing the ride into several different sections (typically 2 or 3) and having sensors on each train, tracking their locations. The coaster’s software is written in a way that only allows one train onto each “block” at a time, so a train can be stopped at the end of every block if it is getting too close to the train in front of it, making a collision impossible.
Lastly, but not leastly, Programmable Logic Controllers (PLCs) are the computers used to control the roller coaster’s operation. PLCs are capable of automatically detecting faults and errors with the ride’s status and mechanics, preventing a ride from starting if a possible error could occur. They also decide when to invoke boosts, brakes, track-switches, cameras, environmental elements, and lifts all based on the current state of the ride and configured actions of operation assigned by its software, ensuring the ride does what it needs to in order to work properly, and can alert technicians if something doesn’t look right.
Lots of people love coasters, including me (although I hate to admit I can’t ride them like I used to due to my mother’s motion sickness genetics), it’s comforting to know just how safe roller coasters really are and how technology is used to ensure they remain safe; the vast majority of amusement park ride accidents occur due to rider misconduct, rather than the coaster’s operation. What may be less comforting is how much more likely you are to die on your way to the amusement park than on a ride, so buckle up, because humans are way worse at making mistakes than physics and programs.
