Eeeeeyyooowiiii!!!

By Richard Woodbury

From the crest of the first towering hill on the new Texas Giant roller coaster at Six Flags Over Texas, riders can enjoy a glittering view of the Dallas skyline 16 miles distant. But few manage to look at it. They are staring down in horror at the gaping 14-story plunge awaiting them. As the red, white and blue cars slide slowly over the edge and then barrel down the $ 137-ft. incline at 62 m.p.h., the screaming riders begin 90 seconds of tightly orchestrated horror.

Tearing out of the first dip, they reel from the force of 2.7 Gs -- nearly the gravity load that hits shuttle astronauts on their climb to orbit -- but only for an instant. Then they are shooting skyward for 100 ft., only to dive abruptly again, down the second of 21 more hills. Frightening twists and turns dot the nearly one-mile course, and disaster seems inevitable as the train hurtles back and forth through its creaking wood supports. Finally, the sudden squeal of brakes in the station signals a merciful finish, and the stunned but happy passengers scramble off.

The Giant is one of a new class of faster, higher and wilder roller coasters roaring onto the amusement-park scene this summer. Far more terrifying than rides of old, the megacoasters, with names like Viper, Iron Wolf and Georgia Cyclone, employ computer technology, ultramodern materials and aerobatics to deliver a plexus punch to those brave enough to step aboard. Park operators are also souping up old coasters and bringing others out of mothballs in a race to produce the terrifying rides. A total of 176 coasters are running in the U.S., up from 147 in 1978 and the most since the heyday of the 1920s.

"The aim is to build in every bit of fright imaginable. Riders want it," explains coaster designer Ronald Toomer. Most of the new roller coasters are constructed with tubular steel, which lends itself to loops and corkscrew twists. But a number of coaster builders are putting modern tracks and cars within a traditional latticework of wood, which provides the sense of ricketiness, danger and nostalgia that riders love. In fact, roller coasters are safer than ever. Unlike old coasters, which speed out and back over often predictable sets of hills, today's rides careen through tight turns, 60 degrees plunges and dark tunnels, sometimes spinning riders upside down. There are coasters on which passengers ride standing up, others that run backward and still more featuring cars that are suspended below the tracks. At Houston's AstroWorld, the outrageous Ultra Twister hurls its riders headfirst from nine stories up, then barrel-rolls them back and forth through a winding tunnel of steel pipes.

To achieve these extremes, designers create computer-simulation models that show the effects of high speed and sudden force on the riders, the cars and the structure. This enables engineers to build roller coasters with the steepest possible inclines and most sharply banked curves to create the illusion of breakneck speed. All roller-coaster trains are actually gravity propelled after the initial chain-drawn ascent and thus steadily slow down from the first big hill onward.

Engineers have outfitted trains and tracks with tougher steel and replaced dual car axles with single axles that swivel to enable cars to take banked turns faster and more smoothly. To prevent meltdown at high speeds, wheels have been enlarged and coated with heavy polyurethane treads.

Most rides are directed by two sets of programmed logic controllers encased in small bunker-like rooms beneath the stations where riders board the cars. The computers monitor the distances between trains by means of solid-state sensors embedded in the rails. If a train slows or stops, others behind it are halted. Multiple sets of pneumatic brakes can automatically slow a train down midway through the course. By allowing the new coasters to run three or more trains at the same time (as opposed to one on old rides), the electronics have boosted rider capacity from an average of 500 people an hour to more than 2,000.

Park operators say the technology has also improved safety. Some coasters, like nuclear-missile launchers, require two attendants, pushing separate buttons, to dispatch a train. Critical parts are X-rayed and stress-tested. Padded steel lap bars and seat belts make it nearly impossible for riders to fall out.

"Operator error has been eliminated," asserts Richard Kinzel, president of Ohio's Cedar Point park. Says Paul Ruben, editor of RollerCoaster! magazine: "If people really knew how safe they are, roller coasters would lose a lot of their thrill." Still, mishaps do occur. On opening day in April at Kansas City's Worlds of Fun, one train of the year-old Timber Wolf coaster rear-ended another approaching the station, sending nine people to the hospital with minor injuries. Timber Wolf resumed operations after its computer system was replaced.

As coaster builders plot more devilish creations, they see no restraints on how high or fast the rides can go. "The only limits are money and real estate," declares Cincinnati structural engineer Curtis Summers, who has designed 27 wooden coasters. "The higher you go, the more land it takes to dissipate that energy." More uncertain is how much additional fright the average rider can endure. Signs at coaster entrances routinely discourage riders with heart, back or blood-pressure problems. Richard Brown, a Cleveland biomedical engineer and consultant to the industry, sees no immediate problems if the rides are kept relatively smooth. But he concedes that "the psychology of how much you frighten people is a consideration."

For the legion of admirers who queue up to ride, however, getting terrified is what coasters are all about. "It's the ultimate daring adventure that pushes the edge of our own bravery," explains Randy Geisler, president of the American Coaster Enthusiasts, which has tripled its membership to 3,200 in five years. That sentiment was echoed by Greg Blum, 15, of Dallas as he bounded off the Texas Giant recently. "That was almost too much to stomach," he cried. "Let me on again."