|Originally Released 12/97 |
|Ellen Morrissey or Donald Lehr |
From Outlaw Amusement to World-Class Sport:
Snowboarding Engineers an Olympic Debit
From the curve of a skate to the slope of the luge, engineering will be a crucial player at Naganoand the new Winter Olympic sport of snowboarding is a prime example.
Snowboarding may seem like the slacker version of skiing, but an organization no less distinguished than the National Engineers Week Committee is spearheading an effort to let the world know that when it comes to geometry, chemistry and bio-mechanics, the newest sport of the Winter Olympics is engineering at its purest.
After more than 30 years on the edge of mainstream athletics, snowboardingthe bad boy of winter sportswill come of age next February when it debuts at the 1998 Nagano Olympiad. This official imprimatur marks a dramatic rise in status for a sport mostly known, at least until now, as a pastime for daredevils with baggy jeans and messy haircuts.
Yet, according to the National Engineers Week Committee, a consortium of more than 70 of America's most prestigious engineering societies and corporations dedicated to increasing public awareness of engineering in our daily lives, that casual facade belies a discipline as dependent on the intricacies of hard science as engineering itself.
"Snowboards have introduced an engineering marvel," says Beat (pronounced Bay-ott) vonAllmen, a civil engineer whose Salt Lake City firm specializes in planning and engineering ski and mountain resorts and who competed with the Swiss ski team in the 1964 Winter Olympics at Innsbruck. He notes that the camber, or arch, of the snowboard, which allows the deft turns that is the signature of the sport of snowboarding, created so much fun for the rider that ski manufacturers quickly lifted the idea for use in their equipment. "It has accelerated the evolution of skiing by introducing the freedom to make a turn without effort."
It has also introduced some heavy-duty chemistry. Take the composition of the snowboard. Through layered combinations of fiberglass, wood, epoxy, polyurethanes and engineering wonders such as Kevlar (created from the discovery of a polymade solvent in 1966 by a woman engineer, Stephanie Kwolek), snowboard manufacturers tune the flexibility of the board.
The board's "flex pattern," its stiffness, determines how it responds to the rider, who exerts two forces while performing in the two categories of Olympic snowboarding: alpine, which is all about downhill racing, and freestyle, which is all about tricks. First, there's the downward energy of the rider's weight, known as a "normal force," and then there's the energy exerted during a twist, known as a "moment force."
While it may appear as rigid as a skateboard, snowboards are pliable enough to wrap around a tree, though most riders specifically aim to never prove that point. Achieving the perfect balance of pliability and stiffness, however, is critical. If the board is too stiff, it will break like a diving board that won't spring. Conversely, if the board is too flexible, or "damp" (what snowboarders call a "noodle"), it will buckle, a dangerous possibility if you're hurtling down a hill at speeds up to 70 miles an hour and pulling up to two-and-a-half G-forces rounding a corner.
So board manufacturers must apply a quantifying formula to the board's construction. They must figure the thickness of the wood core, the thickness of the fiberglass, the orientation of the fiberglass weave, and the density of the epoxy that glues it all tight. Too much glue and the board becomes too heavy. Too little and it breaks. And the board's stiffness must be finessed every inch of its length, because the nose and tail must be soft enough for turning, but in the center, beneath the rider's feet, it must be stiff enough for stability.
As might be suspected, the exact composition of each board is among the most tightly guarded of trade secrets among manufacturers.
Besides the relationship between rider and board, there's also plenty going on between board and snow. From the time the nose of a snowboard hits a patch of snow until the tail passes over it, the National Engineers Week Committee points out, an amazing piece of thermodynamics takes place. As the nose hits the snow, it encounters frozen water particles, but the friction of the board causes an instant heating that turns the snow into water.
Thus, the board is floating on water during its entire run over snow, which is constantly subjected to what physicists call a "phase transition" of turning from ice crystals into water. At the tail of the board a second phase change takes place as the abrupt end of friction returns the water to snow. This puts an incredible demand on the gliding wax applied to the board's underside which must smoothly facilitate the rapidly changing forms of H2O.
To accommodate this, top riders and coaches often carry full complements of various waxes. Before each run, they measure snow density, snow temperature and air temperature and pick their wax or waxes accordingly. Just as manufacturers consider the formulation of their boards' composition to be top secret, riders and coaches jealously guard their selection of waxes.
Finally, there is the simple geometry of the board. Besides camber, length, width, tail, and nose, there is the sidecut to consider. The sidecut gives the board its hourglass shape when viewed from the rider's vantagepoint. Just as it does with skis, the subtlety of the sidecut directly relates to the board's ability to make a turn. Measured in terms of the radius of a circle that cuts into the board from the side, a 15-meter sidecut would allow ease of handling but require a wide berth for turning. A drastic six-meter sidecut, by contrast, would be a bear to handle, but make for a wickedly tight turn.
Beyond its dependence on the hard sciences, even the pedigree of snowboarding is rooted in engineering. The National Engineers Week Committee proudly points out that the first snowboard was made by an engineer. In 1965, an industrial-gases engineer, Sherman Poppen of Muskegon, Michigan, saw his daughter attempting to stand up on her sled while sliding downhill. Using dowels, Poppen screwed two child snow skis together and gave it to his daughter, who created a local rage for the new invention.
Thirty-three years later, that engineering flight of fancy moves front and center on the world stage.