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The most blood-curdling coasters in the U.S.

Looking for a good scare? These fiendish rides will give you goosebumps Gene J. Puskar  /  AP file
Originally called the Steel Phantom, this coaster at Kennywood, in Mifflin, Penn. was modified in the 2000-2001 off-season and renamed Phantom's Revenge. The original four loops were taken out, and the drop of the coaster increased to 228 feet. Max speed: 82 mph.
By Lisa LaMotta updated 10/29/2007 1:43:56 PM ET 2007-10-29T17:43:56

Zero to 128 miles an hour, straight up, like a rocket, then down 41 stories, twisting in a 270-degree spiral. Total time: 28 seconds.

No, we're not talking about the subprime mortgage market. This is Kingda Ka, the tallest and fastest roller coaster in the world, which opened at Six Flags Great Adventure in Jackson, N.J., back in 2005.

If you're looking for a good scare, modern coasters like Kingda Ka can deliver. As well they should: Some of the nastiest cost up to $25 million to design and build, let alone maintain.

"On Kingda Ka, it was very clear from the beginning that [Great Adventure] wanted to have the highest ride, the fastest ride," says Andreas Wild, an engineer with Stengel Engineering in Munich, Germany, which worked on the coaster in conjunction with Intamin, a manufacturer. "It was the top priority for the project."

Erecting one of these monsters is a ton of work. Take another Stengel project, Maverick, a 105-foot tall, two-and-a-half-minute long steel beast that opened last May at Cedar Point in Sandusky, Ohio. "It was a three-year project from the initial talks and concepts to the introduction of the ride," says Tony Clarke, a company spokesperson.

The design phase takes about a month, says Wild. With coasters, everything is mapped out—from height and speed to colors and movie-themed tie-ins. Superman: The Escape—a $20 million coaster at Six Flags Magic Mountain in Valencia, Calif.—minds the details right down to the entrance, modeled after Superman’s crystal fortress of solitude.

Even local culture plays a role in coaster design. While Americans and Brits crave height and speed, for instance, "in southern Europe, especially Spain, [riders] are concerned about loops and screws," says Wild. "They don’t want to go that fast."


Lately, Wild and other designers have been looking to airplane acrobatics for chilling inspiration. Take the "Immelmann" loop, named after a tenacious German pilot who flew during WWI. In this design, the track bends into a normal loop, flipping riders upside-down, only to flip them right-side-up as the loop is completed.

Most designers and manufacturers are located in Europe; many manufacturers do their own designs as well. To help it compete, Stengel writes its own project-management software. "We build most of our own programs because there is nothing on the market," says Wild. "There is no such thing as 'Roller Coaster Office.' Maybe Microsoft and Bill Gates haven’t thought of that yet." Tim Larsen  /  AP file
The Kingda Ka, at Six Flags Great Adventure in Jackson , N.J., is the fastest roller coaster in the world and goes from 0 to 128 miles an hour, straight up, like a rocket, then down 41 stories, twisting in a 270-degree spiral. Total time: 28 seconds. Need we say more?
As for safety checks, designers run a battery of computer simulations on new coasters, while park maintenance crews scour daily for fractures or sticky control systems. Six Flags has more than 900 full-time maintenance employees at its 31 parks. But all of those precautions don't make some of these rides any less intimidating.

So where can you find the scariest coasters around?

With help from the folks at the Roller Coaster Database, Forbes.com assembled a list of the most blood-curdling of the bunch, weighted by top speed, height and drop, in that order of significance. (Reason: Many modern coasters run on both gravity and additional propulsion systems, so top speed can be independent of height.)

After Kingda Ka comes the Top Thrill Dragster, another Cedar Point favorite. Opened in 2003, its yellow and red steel frame towers a dizzying 420 feet high; passengers hit a maximum speed of 120 mph.

Superman: The Escape took the No. 3 spot, followed by Millennium Force (also at Cedar Point) and Titan at Six Flags Over Texas, in the town of Arlington.

Of the top 10 scariest coasters, half are open to the public from April through October. The others are open on weekends throughout the winter. No. 8, called Xcelerator, at Knott's Berry Farm in Buena Park, Calif., is closed only on Christmas.




