In the summer of 1895 crowds flooded the Coney Island boardwalk to see the latest marvel of rollercoaster technology the flip-flap railway. This was America’s first-ever looping coaster, but its thrilling flip came at a price. The ride caused numerous cases of severe whiplash, neck injury, and even ejections all due to its signature loop.
Today coasters can pull off far more exciting tricks without resorting to the thrill of a hospital visit.
What exactly this rollercoaster is doing to your body? And how have they managed to get scarier and safer at the same time?
At the center of every rollercoaster design, is gravity. Unlike cars or transit trains most coasters are propelled around their tracks almost entirely by gravitational energy. After the coaster crests the initial lift hill it begins an expertly engineered cycle, building potential energy on a sense and expending kinetic energy on descents. This rhythm repeats throughout the ride acting out the coaster engineers choreographed dance of gravitational energy. But there’s a key variable in this cycle that wasn’t always so carefully considered, that’s you.
In the days of the flip-flap, ride designers were most concerned with coasters getting stuck somewhere along the track. This led early builders to overcompensate hurling trains downhills and pulling on the brakes when they reached the station. But as gravity affects the cars it also affects the passengers and under the intense conditions of a coaster gravity’s effects are multiplied.
There’s a common unit used by jet pilots astronauts and coaster designers called G-force. One G-force is the familiar tug of gravity, you feel when standing on earth. This is the force of Earth’s gravitational pull on our bodies. But as riders accelerate and decelerate they experience more or less gravitational force.
Modern ride designers know that the body can handle up to roughly 5G’s, but the flip-flap and its contemporaries routinely reached up to 12G’s. At those levels of gravitational pressure, blood is sent flying from your brain to your feet, leading to lightheadedness or blackouts. As the brain struggles to stay conscious and oxygen deprivation in the retinal cells impair their ability to process light causing greyed out vision or temporary blindness. If the riders are upside down, then blood can flood the skull, causing a bout of crimson vision called a readout.
Conversely, negative G’s create weightlessness within the body. Short-term weightlessness is mostly harmless, it can contribute to a rider’s motion sickness by suspending the fluid in their inner ears which coordinates balance.
The bigger potential danger and thrill comes from what ride designers call air time, this is when riders typically experience seat separation and without the proper precautions ejection. The numerous belts and harnesses of modern coasters have largely solved this issue. But the passenger’s ever-changing position can make it difficult to determine what needs to be strapped down.
Fortunately, modern ride designers are well aware of what your body and the coaster can handle. Coaster engineers play these competing forces against each other to relieve periods of intense pressure with periods of no pressure at all. Since a quick transition from positive to negative G-force can result in whiplash headaches and back and neck pain. They avoid extreme changes in speed and direction so common in thrill rides of old
Modern rides are also much sturdier, closely considering the amount of gravity they need to withstand. At 5 G’s your body feels five times heavier, so if you weigh 100 pounds you’d exert the weight of 500 pounds on the coaster. Engineers have to account for the multiplied weight of every passenger when designing a coaster supports.
Still, these rides aren’t for everyone. The floods of adrenaline, lightheadedness and motion sickness aren’t going anywhere soon. But today’s redundant restraints, 3d modeling, and a simulation software have made roller coasters and more thrilling than ever.
Our precise knowledge about the limits of the human body has helped us build coasters that are faster taller and loopier and all without going off the rails.
In terms of human evolutionary instincts, rollercoasters don’t make a lot of sense. But people love to be scared.