Ticket to Ride

By Jeffrey KlugerAug 1, 1992 5:00 AM


Sign up for our email newsletter for the latest science news

This summer Cedar Point amusement park in Sandusky, Ohio, celebrates the one hundredth anniversary of its first roller coaster. Frankly, I can’t imagine why. To me the idea of the leisure industry celebrating 100 years of roller coastering is roughly akin to the medical industry celebrating 100 years of proctoscopy. No doubt there would be some people who’d consider the occasion worth commemorating, but I, for one, would not want to attend the press event.

It was in 1966, during a summer-camp field trip, that I took my first ride on a major roller coaster. Even before we set out, the expedition seemed fishy to me. The way I understood it, my cabinmates and I would be hustled into buses after dark, driven to an undisclosed location, force-fed enough junk food to feed the population of Micronesia, strapped into rickety carts, and sent speeding along a wooden track in an excruciating demonstration of every physical law Newton ever proposed. Sounded like a great plan.

The actual roller coaster experience was every bit as horrific as I’d anticipated, culminating in my losing lunches I wasn’t even scheduled to eat until the following month. When I finally set foot back on the ground, I loudly swore off roller coasters forever. It was a vow I was able to keep for 26 years until--in the name of research--breaking it last spring.

As a lifetime loather of all things coaster, I am in a very small minority. In this country there are over 200 roller coasters up and operating. Cedar Point itself boasts 10, holding the Guinness record for number of coasters at one site. In this year alone, fully a dozen new roller coasters are opening nationwide.

No one knows when the first roller coaster appeared, but recently released tablets put the date at perhaps 20,000 years ago, which was, regrettably, a good 15,000 years before the invention of the wheel, the track, or the festively painted cart. Primitive roller coasters thus consisted of nothing more than a sheer cliff, off of which primitive tourists were invited to jump (provided they met the minimum height requirement). This, of course, turned out to be murder on repeat business, as well as on the T-shirt concessionaire who had inadvisedly set up his stand at the bottom of the cliff.

The first real roller coasters--the ones that have the historical advantage of having actually existed--were built by the Russians more than 400 years ago. These Russki-rollers consisted not of carts but of sleds, which slid along an inclined snow-covered track supported by wood scaffolding. It wasn’t until the early nineteenth century that the French adapted the idea, changing the sled blades to wheels and the snow track to dry rails--and no doubt adding an on-board fruit-and-beverage service as well.

Modern coasters fall into two categories--wooden or steel--and are designed by people who fall into one category: terrorists. Actually, this isn’t true; roller coasters are designed by a special type of person, one who from an early age dreams of gathering up hundreds of folks he’s never met before, placing them in tiny carts, hauling them high into the sky, and, for no apparent reason, dropping them straight down to the ground. Terrorists usually draw the line at car bombs.

One of the country’s most accomplished--and most congenial-- roller coaster designers was Curtis Summers, head of the aptly named Curtis Summers, Inc., in Cincinnati. Summers started his career as a garden- variety engineer, went into the coaster dodge in the mid-1950s, and kept at it until his death last May. After nearly four decades of work, he left the world’s thrill lovers a considerable coaster legacy, building 31 roller coasters of different sizes and designs, including a new 20-story model on the Japanese island of Kyushu. Talk about your effective forms of Japan bashing.

I didn’t always want to design roller coasters, Summers told me when I talked to him early last spring. But right after the Navy, I started working with the Old Coney Island park in Cincinnati, helping renovate their existing coasters so they could accommodate faster cars. After a while I just got caught up in it.

Roller coasters, Summers explained, are based on some pretty simple physics, and for most of their route rely on just one form of fuel: gravity. As a roller coaster begins its ride, Summers said, it is hauled up an incline by an ordinary chain drive. This introduces potential energy into the system. At the top of the incline that energy is released simply by pushing the train forward and allowing it to roll downhill. People sometimes ask why roller coaster designers always put the biggest hill at the beginning of the course, but this is the only way to build up enough momentum for the whole ride. On any roller coaster, every hill will always be smaller than the one before it, since energy declines the farther you go.

Pulled by gravity alone, roller coasters can attain speeds as high as 80 miles per hour, which is 25 miles per hour faster than you should travel in a Country Squire station wagon, let alone in a sort of Flexible Flyer on rails. Speed, however, doesn’t travel unaccompanied; also generated are g’s. These, it’s important to point out, are not the same things as Gees, which are often produced by people who are actually having fun. G’s are those things created by an ascending rocket or a centrifuge, which, if you remember The Right Stuff, used to flatten most astronauts’ faces into something resembling a flesh-toned jack-o’-lantern-- only not as handsome. This explains why all the Life magazine photos were taken before the flights.

Generally we don’t let the g-forces on a coaster get above 3.5, said Summers, or about 3.5 times the pull of gravity. Jet pilots generally black out at about 10 g’s and brown out at about 8.5. Beyond 3.5, we find, ordinary people become frightened. And become plaintiffs.

G-forces accumulate only when the coaster is climbing. As it speeds downhill, the pull of gravity is actually reduced, producing negative g’s, or a feeling of weightlessness. Astronauts orbiting the Earth experience zero-g, said Summers. On a roller coaster we go no lower than .2 g. This is enough to give people the thrill of being airborne but, in a worst-case scenario, keeps them in the car if the lap bars or seat belts fail.

Assuming high g’s don’t reduce you to a flapjack with shoes, and low g’s don’t launch you into an adjacent zip code, you still have to concern yourself with horizontal motion--that phenomenon you experience on a bus when a sharp turn crushes you against the muttering man in the aluminum-foil hat sitting just to your left. The two biggest things that determine horizontal motion, said Summers, are speed and radius of turn. When the train comes out of the station, you’re going less than 10 miles per hour, so your turn can have a radius as little as 30 feet. At 60 miles per hour, that radius has to grow to about 115 feet to keep horizontal motion down. Even the widest turn, however, can still get you a little cozy with your seatmate. To eliminate this remaining bumping and--not incidentally--to help keep the car on the track, the turns are banked.

On very low speed turns, tracks are banked perhaps three or four degrees, said Summers. On high-speed turns with the widest radii, the bank is up to 65 degrees. The whole purpose of this is to make the force of the turn move down through the rider and into the seat. Bank any further than 65 degrees, of course, and you run the risk of having something else pass through the rider and wind up on the seat.

Indeed, throughout the body, the effect of all this bucking, heaving, and weaving can be decidedly unpleasant. Even before the roller ride begins, the stomach has already started to secrete extra acid, courtesy of the fight-or-flight response (which, in the case of roller coaster riders like me, is also known as the fight-flight-and-openly-weep response). When the coaster is actually under way, the increase in g-forces causes the stomach to flatten out. This sudden squashing can lead to the surprise reappearance of the chili dog and fries you ate only half an hour earlier and, in extreme cases, of every morsel of food you’ve consumed since roughly the mid-1970s.

Also affected by roller coaster motion are the semicircular canals in your inner ear and the bursas--or sacs--that surround all the joints in your skeleton. When you move your head or body even a little bit, fluid in the canals and bursas sloshes against tens of thousands of tiny nerve endings, sending signals to your brain that tell it which way is up, which way is down, and so on. In a violently moving vehicle, the fluid splashes around so erratically that the nerve endings get confused, sending signals that they don’t know which way is up, that they frankly don’t care, and that if the brain thinks it’s ever going to talk the rest of the body into getting on a roller coaster again it’s got another think coming.

Things can get even messier when riders take their stomachs, ears, and bursas from a wooden coaster to a state-of-the-art metal model. Roller coaster enthusiasts debate the relative merits of woodies and steelies with the same vociferousness that hunting enthusiasts use to debate the relative merits of shotguns and assault weapons--though coaster enthusiasts typically have opposable thumbs and upright posture.

Among the advantages of woodies, Summers cited the clickety-clack sound created by the interplay of metal wheels, metal tracks, and an underlying wood framework. This, he explained, can be more exciting than the relatively silent steelies, which use neoprene coatings on the wheels to keep down the din that would be created by steel on steel on steel. The most dramatic difference, however, is the comparative lack of variety that wood provides in track design. Since metal is much more flexible than wood, only the metal coasters have the loop-the-loops, corkscrews, and other features generally frowned upon by representatives of Amnesty International.

In designing early metal coasters, engineers had to learn as they went along. The first 360-degree loop-the-loops, for example, were designed as perfect circles, which turned out to be aesthetically pleasing but physically bad. The relatively gentle curve made the coaster lose speed at the top of its climb, lowering centrifugal force and causing upside-down riders to drop out of their seats. While this feature helped reduce annoying lines at ticket booths, it proved unpopular with fussy fairgoers. Eventually loop-the-loops were redesigned into a sort of teardrop shape-- called a clothoid loop--which sharpens the upper portion of the curve, keeping both speed and centrifugal force high.

Other such design refinements involve the corkscrew, which is typically built to resemble a sort of stretched spring lying on its side, with the cars riding around and around on the spring’s interior. When the design was first tried, engineers discovered that the large number of turns and the track friction led to a loss of momentum and a slow-moving coaster. The answer was to lift one end of the corkscrew a bit, so that while the train spirals it also heads slightly downhill.

Ultimately, of course, there was only so much I could learn by talking to the guys who design these rides. If I really wanted to understand coasters, there was just one truly courageous way to do it: pay an anonymous party an enormous sum of cash to ride a coaster for me and tell me all about it. Unfortunately, I didn’t have an enormous sum of cash, so the only alternative was to go myself.

I chose to take my roller ride at Six Flags Great Adventure in Jackson, New Jersey--mostly because it’s just a short drive from my home, which gave me a little extra time to get my personal affairs in order. Great Adventure is a gigantic park with several coasters to choose from, all of which have names like The Great American Scream Machine, The Shock Wave, and The Major Cranial Surgery Without Anesthetic. I opted for the comparatively tame sounding Rolling Thunder, not only because of its name, but also because it was the only woodie in the park, which meant it was the only one that didn’t elevate g-loads and trigger nausea in people while they were still waiting in line to buy tickets.

When I finally arrived at Rolling Thunder, I was dismayed to learn that my coastering experience would not be even a semiprivate one. Safety regulations require that weight in coaster trains be distributed evenly, which means that every car must have two people riding in it. I was paired with a sort of generic teenage boy who had that generic teenage habit of shouting Woooo! in a really high pitched voice whenever he got excited by something. Unfortunately, exciting moments for him included not only riding in roller coasters but standing in line at them, so by the time we were finally seated in our car our relationship was already in trouble.

The actual ride could, I suppose, have been less pleasant--but only if the train had left the tracks, plunged to the ground, and embedded itself in the mantle of the planet. The climb to the top of the first hill was interminable, and while the other riders spent this period gazing around at the dwindling panorama beneath us, I chose to stare at my equally scenic feet.

When we moved over the crest of the hill, I was nothing short of horrified at the sensation. The 80 percent reduction in g-force reduced my body weight to what I quickly calculated was 29 pounds--clearly too little for my 5-foot-9 frame. I briefly considered asking my seatmate if he was using his .2 g and if I could maybe have it, but he was due for a woooo and I didn’t want to disturb him.

When we reached the bottom of the hill and started back up, of course, I had more g’s than I could possibly want, transforming me and my stomach lining into something resembling a human-size decal on the back of my seat. The remainder of the ride was a series of steadily smaller climbs, drops, and hairpin turns, producing the same--if less severe--sensations. By the time we pulled back into the station, my hands were locked into talons, my face was frozen into something resembling an electrocuted Art Garfunkel, and I found myself renewing my 1966 vow never to go near a roller coaster--or for that matter a bumper car, a flume ride, or a piece of wheeled office furniture--again.

A funny thing happened, however, after I left the station, when I had a chance to catch my breath, regain my bearings, and reflect on the experience I had just had. That funny thing was: I hated it even more. I know, I know, I’m supposed to say I suddenly understood the exhilaration, the liberation, the sense of freedom roller coasters provide. But I just didn’t. I don’t like them and that’s that. I don’t doubt other people do-- dozens of happy folks on the very train I was on obviously did. But other folks also like blue cheese, so what does that prove? For my money, I’d just as soon explore gravity in a La-Z-Boy, banking at Chase Manhattan, and inertia on a good two-week vacation in Aruba. You wanna build that kind of theme park? I’ll be the first in line.

1 free article left
Want More? Get unlimited access for as low as $1.99/month

Already a subscriber?

Register or Log In

1 free articleSubscribe
Discover Magazine Logo
Want more?

Keep reading for as low as $1.99!


Already a subscriber?

Register or Log In

More From Discover
Recommendations From Our Store
Shop Now
Stay Curious
Our List

Sign up for our weekly science updates.

To The Magazine

Save up to 40% off the cover price when you subscribe to Discover magazine.

Copyright © 2023 Kalmbach Media Co.