September 2004, Issue #32
Feature Article – Roller Coaster Engineering – Exclusive reprint from The Fantastical Engineer (Bonamy Publishing, 0-9664762-2-8 $17.95).
According to a 1997 roller coaster census, there were 871 operating coasters worldwide.
Roller Coaster Design
No discussion on themed entertainment would be complete without at least a mention of roller coaster design. Roller coasters are in many theme parks and of primary concern to aspiring designers. When asked the question, "If you could design any ride in a theme park, what would it be?" Most of us thrill seekers inevitably choose the biggest, baddest and most exhilarating ride imaginable. We begin with roller coasters.
Click-clack up the hill it goes to drop into a death defying corkscrew roll. The machine has us out of our seat and screaming our confessions so that this thrill may not be taken away from us. The most famous coasters are referred to by terms like Scream Machine and given names such as Atom Smasher, Mind Bender, Cyclone, Beast, Steel Phantom, Thunderbolt, and Giant Dipper, and with good reason.
In the year 2000, coasters were being built bigger, faster and more intense than ever. Parks now have 30 different types of coasters to choose from and are adding them by the handful. According to an April 2000 interview in Park World Magazine, "advancements in technology are allowing manufacturers to build new and unique types of coasters which give theme parks unlimited choices when shopping for the next great marketable attraction," observes Jim Seay, president of Premier Rides. "Theme parks are buying coasters because it is smart business. It has been proven time and time again that new coasters quickly pay for themselves and bolster annual attendance. The average attendance at parks that added Premier Rides coasters in 1999 was up 43 percent. That is a strong statement for the business side of introducing new roller coasters." In 1998, 300 million people descended on amusement parks to experience thrills achievable in no other way. We want to be hurled around the track at incredible speeds; we want to be terrified and we want to have fun in complete safety. When the ride is over, we rush back into line to do it again.
Enthusiasts are constantly in search of steeper hills, more G's, tighter rolls, and more airtime. Today, roller coaster design is all about what the human body can withstand. The Steel Phantom and Fujiyama reach lightning speeds of 85 M.P.H. A new coaster, Millennium Force, released in May 2000 reaches 92 M.P.H., and Superman Kryton Coaster, the world's tallest and fastest floorless coaster reaches 70 M.P.H.
Roller coaster designs may take 2 or 3 years to complete and cost as much as $8 million. The design of coasters is now done on computer using CAD systems and the safety of riding has increased considerably. CAD systems can design the layout as well as calculate the forces and stresses on riders and the ride itself.
Designing roller coasters is practically an art form. In the simplest terms, a designer wants to create a ride that is heart-stopping, exhilarating, thrilling, addictive, and safe. You must provide the ultimate thrill or experience but not leave the riders feeling like they have been run over by a MACK truck.
G-Forces are the various forces or pressure your body encounters on a coaster ride. Actually, negative G's is airtime, or coming out of your seat, while positive G's are the force your seat is exerting against you. A good design will usually not exceed 4 G's or the pressure that makes you feel as if you weigh 4 times your current body weight. Obviously, when designing a ride that descends 225 feet, as the designer, you must be sensitive to how those forces are applied to the human body. Every element of the design, from the corkscrew loops to the sudden accelerations, will put some kind of stress on the riders. Just watch the face distortions of riders shooting down the entire 225 feet of the Steel Phantom.
The fate of the coaster lies in the forces and velocities the designer decides to apply to your body at the precise moments. Horizontal forces as well as airtime forces also need consideration from the designer. Remember the last time you rode a coaster and how you were squashed into the corner (lateral G's) or onto the person next to you when looping around a tight corner? You felt that because when the coaster moved into the turn, your body and the coaster wanted to continue moving in a straight line. According to Ron Toomer, the designer of Kennywood's Steel Phantom, "we bank the track to push the coaster into the turn." Designers attempt to convert the momentum to downward force so you don't squish the rider next to you. However, the landscape and the space available can be limiting. Coasters are all about gravity. The first hill is always the highest to gain enough speed to make it through the rest of the track. When the Steel Phantom opened in 1991, it was the tallest and fastest coaster ever with a 225-foot drop. "When you are building something like the Steel Phantom, you don't worry too much about making it scary. It's scary already," said Toomer.
General Roller Coaster Info
Lots of great information about Roller Coasters
http://www.me.utexas.edu/~uer/roller/index.html
The use of different materials in building roller coasters
http://www.tms.org/pubs/journals/JOM/0205/Byko-0205.html
Activities
Physics Day at a Theme Park
http://ali.apple.com/ali_sites/ali/exhibits/1000910/
Design a virtual roller coaster
http://www.learner.org/exhibits/parkphysics/coaster/
Amusement Park Rides: Ups and Downs in Design
http://www.wepan.org/pdf/activities/roller_coaster_7_8.pdf
The It's a Wild Ride Project
http://www.netc.org/classrooms@work/classrooms/
middleteam/learning/
