Tricks of The Trade

Ever wondered what keeps a ski jumper flying or a luger on track? Here are some answers
January 27, 1988

GILT TRIP
At Calgary all that glitters won't be gold, including the gold medals, which, like those awarded at other recent Olympics, will actually consist of 6.73 ounces of gilded sterling silver. The medals will be only a 10th of an inch thick and worth about $400 each.

FLAT OUT
A luger often turns a blind eye to danger, and he or she will try to visualize the course before lying supine on the sled. But once the run has started, the luger stares at the sky much of the time. This is because raising the head increases wind resistance and slows the sled.

GLIDING VS. SKATING

The way Gerhard Grimmer of East Germany won a 50-km cross-country race in 1971 at Holmenkollen, near Oslo, may have been unorthodox, but it worked. That year fluky snow conditions forced racers to stop repeatedly along the course to rewax or change skis. Grimmer didn't bother. Instead, he abandoned the parallel technique, the graceful gliding motion of classic—as it's now called—cross-country skiing (above, left), and began "skating" (above, right) by pushing off the inside edge of his weight-bearing ski. He won by seven minutes, the equivalent of winning a marathon by a mile.

Since then, variations on Grimmer's technique have gradually transformed cross-country competition. And that has also made a lot of purists pretty hot under the skis. Why? Because the skating method is very fast. Most classic skiers don't stand a chance against well-trained skaters, and many European sports officials, particularly those from the U.S.S.R., Norway and Finland, have tried to get the Fèdèration Internationale de Ski to strictly limit skating in races. "They just didn't like it because it was a change from the sport they think they invented," says John Caldwell, former coach of the U.S. cross-country team.

But you can't keep a good technique down. In 1986 a Solomonic bargain was struck: Half of the cross-country ski races at Calgary (men's 15- and 30-km, women's 5- and 10-km) will be skied using the classic technique; the others (men's 50-km and 4 x 10-km relay, women's 20-km and 4 x 5-km relay) may be done freestyle, which means that anyone who wants to win those races will skate them.

SMOOTHIES

In sports, loose, rough clothing is a drag, literally. For example, a floppy cotton jersey can boost wind resistance by up to 15%. Engineers calculate that in the 100-meter dash a reduction of as little as 2% in resistance can save a 10th of a second. In an Olympic downhill race, that can be the difference between gold and bronze. But racing in the buff isn't the answer, either. Sleek costumes are de rigueur in winter sports not for fashion's sake but because aerodynamically correct togs offer less resistance than bare skin.

Nobody has taken this principle more to heart than lugers, with their suits made of a rubberlike substance. Rubber rompers may sound a bit kinky, but they make aerodynamic sense. As much as 10% of drag is caused by air molecules coming into contact with the surface of a body. The slick covering a luger wears allows the air molecules to slip past more easily.

JUMPING JACKS

Even in this high-tech age the length of a ski jumper's leap is still measured by the naked eye. During competition, officials stand on either side of the hill, at carefully measured one-meter intervals, watching the skier's feet as he flies through the air. When the skier lands, the official closest to the touchdown point raises his hand to indicate the distance of the jump.

During the Sarajevo Games, 114-pound Jens Weissflog of East Germany was likened to "a piece of paper in the wind" when he won the 70-meter jump, but a better analogy would have been a paper airplane, because a ski jumper gets a similar sort of aerodynamic lift. The skier-inflight gets lift by holding his body at about a 35-degree angle over his skis. As he flies, the air is drawn around his body and skis, causing corkscrew vortices to form (see below). The vortices decrease air pressure over the skier's back and increase pressure below his chest. The pressure differential pushes him upward slightly, keeping him from falling like a stone.

HEAD START

It may look as if a skier is trying to go down the hill on his face instead of his skis when he bursts headlong out of the starting gate (below), but he's actually shaving hundredths of a second off his time. By launching his torso out over the run, the skier is already plummeting downhill by the time his legs knock aside the wand that starts the timer.

At the bottom of the bill, the timer stops when the skier breaks an electronic beam at about knee height. By lifting the tips of his skis, a clever skier can make the skis pass through the beam ahead of his legs.

Lugers have similar tricks. The timer is triggered at the start of the run and stopped at the end by electronic beams aimed three inches above the ice. Many lugers draw their knees up before hitting the beam at the top—thus delaying the timer's start by a fraction of a second—and extend their toes as far in front of the sled as possible at the bottom of the run.

BOBBING ALONG

Before doing an $850,000 bobsled design for the U.S. team, engineers at Airflow Sciences Corp., a fluid-mechanics consulting firm in Livonia, Mich., conducted computer simulations to find out where they should concentrate their efforts. They simulated hundreds of bobsled runs, varying such things as the weight of the sled, starting speed, friction on the sled's runners and aerodynamic drag. To their surprise, it is the athletes who matter most. More important than sled design is push time—how long it takes the sledders to propel their craft and leap into it over the 50-meter starting run. As little as a 10th of a second off push time shaves a quarter to a third of a second off run time, which is plenty of time to determine who will win—or lose—a gold medal.

The engineers' simulations didn't take into account the trickiest part of launching a bobsled—jumping into it without scratching your teammates with the hundreds of needles that project from the soles of your sledding shoes. The needles grip the ice during push time.

KING TUCK

A downhill race goes to the swiftest, and often that's the racer who follows the shortest course. A skier tries to avoid being airborne because time spent in the air increases the distance he must travel. To keep from being pitched skyward by bumps, he prejumps them by pulling his skis off the snow just before they hit the bumps (above).

Downhill racers reduce wind resistance by tucking their bodies into something close to the fetal position (left). The tighter the tuck, the more smoothly air flows around the skier. When the flow is chaotic, eddies are created behind the racer, lowering the air pressure and exerting a slight backward tug.

FIGURE THIS OUT

Unraveling how the judges score Olympic figure skating is just about as difficult as skating the figures yourself. Here's how it works. The competition consists of three events: the compulsory figures, which count for 30% of the total score; the short program (20%); and the long program. The skater is required to perform three figures during the compulsories and seven elements in the two-minute short program—including spins, specific sequences of foot movements and jumps. The freestyle program lasts four minutes for women, 4½ minutes for men.

Now matters get complicated. Each of the compulsory figures is awarded a score ranging from zero to six on the basis of technical merit. The short and long programs get one mark each for technique and one for artistic impression. Fractions of a point are deducted for incorrect technique and for elements missed from the short program. The nine judges keep track of the scores they've given each competitor, and when all the contestants have finished, each judge ranks them by these scores.

There's more. After each event has been completed, accountants compute a skater's total score by this formula: They multiply his rank in the compulsories by 0.6, his rank in the short program by 0.4 and his rank in the long program by 1.0, and add it all together for the skater's total score.

Here's an example. Let's say a skater finishes second in the compulsories, then fourth in the short program and third in the long. His score for the compulsories would be 2 x 0.6, or 1.2. For the short program it would be 4 X 0.4, or 1.6; for the long, 3 X 1.0, or 3.0. Thus his total is 1.2 + 1.6 + 3.0 = 5.8. Oh, yes, the contestant with the lowest score wins.

TWO ILLUSTRATIONSYVONNE GENSUROWSKY/SRW, INC. PHOTONANCIE BATTAGLIA TWO ILLUSTRATIONSROB WOOD/SRW, INC. TWO PHOTOSCARL YARBROUGH TWO ILLUSTRATIONSGREG HARLIN/SRW, INC. PHOTODAVID LISSY PHOTOMANNY MILLAN THREE ILLUSTRATIONS

HOLE YARDS PAR R1 R2 R3 R4
OUT
HOLE YARDS PAR R1 R2 R3 R4
IN
Eagle (-2)
Birdie (-1)
Bogey (+1)
Double Bogey (+2)