has always been an issue with coasters. High speeds and great heights have always made parents apprehensive about allowing their children to go on the rides. Computer design systems have made roller coasters safer by making the designs much more predictable and reliable. After the roller coasters are tested and simulated on the computer, they are built and extensively tested again before they are put into use. Even after they have been made available for the public, theme parks perform routine check-ups on the rides to ensure their safety and they have no qualms about shutting down a ride for repair. Many of us know the disappointment of going to an amusement park and discovering that one of our favorite rides is out of commission for repair. The check-ups ensure not only a secure ride but also one that will last for a long time. In fact most of the roller coasters put into use in the fifties are still in use today, including Matterhorn Mountain [1], [3].
One of the comforting things about the roller coaster experience is that a coaster ride is safer than a normal car trip. The biggest of all safety features in roller coasters is the removal of the possibility of human error. Unlike cars, a roller coaster is controlled by a computer; hence, it is impossible for it to make a bad decision. Also, there is only one cart so there is no chance of miscommunication and dangerous interaction between two vehicles, the leading cause for car accidents. The track that the carts glide on provides a clearly defined path for the ride to follow, so even if the riders don't know what's coming next the designers do. The ability for the cart to be attached to the track, as well as the harnesses that keep the riders in, has provided the designers the ability to design amazing rides that feature corkscrews and loop-the-loops [3]. Loop-the-loops and other features rely in part on centrifugal force
https://illumin.usc.edu/54/roller-coasters/
More than you ever wanted to know about roller coasters


Then I saw this
http://www.express.co.uk/news/uk/582756/alton-towers-roller-coaster-failed-safety-tests-three-times