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  • There's a lot of nerves and excitement

  • you gain quite a bit of speed in a short period of time.

  • So you start kind of getting like tunnel vision almost.

  • And then when you get into the flying

  • you see the whole mountainside just open up.

  • My name is Anders Johnson and I am the Women's World Cup coach for USA Nordic.

  • He's also a 3 time Olympian in the sport of ski jump

  • a sport that's all about using technique in physics to fly as far as humanly possible.

  • And doing that successfully all comes down to this shape.

  • 100 years ago, Olympic ski jumpers looked like this.

  • Skis were held tightly in parallel.

  • Hands in front of their face, kind of like a less posed version of Superman.

  • By the 1950s, jumpers moved their arms back and to the side.

  • But they kept their skis in the same shape.

  • Everyone did, because...

  • The goal here is to fly farther and with style.

  • Farther because the further you land from this line, the more points you get.

  • And with style because judges award more points

  • on top of your distance score, just for looking cool.

  • And for a while, the best, coolest, most stylish way to ski jump was this.

  • In a straight, elegant line, with skis tight underneath you.

  • This parallel position helped athletes cut through the airquickly.

  • It was the standard for decades.

  • That is, until the 1980s.

  • This Swedish guy named Jon Boklov.

  • He struggled with keeping his skis parallel but he noticed on some of the jumps

  • that he, you know, opened up his skis a little bit wider into a bigger v

  • he was achieving longer distances.

  • That's because this position allows you to catch a lot more air with your body

  • than this one.

  • You have kind of two key parameters you're trying to optimize:

  • how fast you're moving forward but also how fast you're moving down.

  • Tess Saxton-Fox is an assistant aerodynamics professor

  • at the University of Illinois Urbana-Champaign.

  • My research is on the flow of air really close to the surface of planes.

  • Air flow is key to ski jumping to because...

  • You want to go down as slowly as possible once you're in the air

  • because you want to stay aloft

  • but you want to go forward as fast as you can.

  • Surface area has a lot of power there.

  • The parallel position has fairly low surface area.

  • It makes the athlete as thin and small as possible.

  • This is actually a pretty good aerodynamic shape

  • if you're just trying to maximize your forward speed.

  • You are lining up your body with the skis

  • and so the air can go around the ski and the body at the same time

  • in kind of the same little bubble that it forms around you.

  • And so that's good actually for reducing drag.

  • What its not good at is resisting gravity.

  • It doesn't do much to prevent you from falling through the air to the ground.

  • In contrast, when athletes open their skis up into a V

  • they're maximizing their surface area by allowing air to directly push against their body.

  • Instead of just trying to be like a bullet, you're trying to be a wing.

  • This position helps create something calledlift.”

  • Yeah, lift is a tricky concept.

  • And it's an important concept, it's the basis for, you know, flight.

  • It's what makes planes fly, what makes birds fly.

  • The key is that as the air kind of moves over the body

  • it kind of follows the shape of the body.

  • So you'll see that they're at an angle.

  • And that's actually really important.

  • If you put your hand out the window of a car and you put it straight

  • it just pushes straight backwards.

  • But if you put it on an angle, you can kind of play with it, right?

  • It'll actually push you up, push your hand up and back.

  • That's really what they're doing is

  • they're putting themselves at an angle so that they get a force

  • that actually wants to push them up as well as backwards.

  • This 1995 paper from the Journal of Applied Biomechanics

  • does a great job of showing this graphically.

  • The researchers used computer simulations to test out different ski styles.

  • Most importantly the parallel style, which they refer to as classic style

  • and the V-style.

  • The V-style generated much more lift.

  • This extra lift means that athletes got more air time

  • which in turn allows further distances and, ultimately, more points.

  • When Jan Boklov first implemented the V-style

  • it was ridiculed it for its ugly appearance.

  • The Chicago Tribune described the switch as going from

  • anelegantly parallel position

  • toresembling puppies leaping into a swimming pool.”

  • And Jan lost style points because of it.

  • "Here's the man with a unique style."

  • While he travelled 78 meters in this 1988 jump, he only got 85.4 points.

  • Denis McGrane of the US travelled the same distance

  • but he used the classic method.

  • He got 90.4 points.

  • Somewhere along the lines in the early 90s, people started to notice that it was effective.

  • Other teams and other athletes kind of started to test it a little bit.

  • By the 1992 winter Olympics, the gold medal was given to

  • Finnish skier Toni Nieminen, a 16-year-old who used the V-style.

  • He traveled 122 meters, beating every other athlete on distance.

  • And as more gold medals went to athletes who used the V-style, the old style faded away.

  • It sort of just became, you know, probably one of the biggest progressions in the sport.

  • Today, you'd be hard pressed to find an athlete who doesn't use V-style

  • or a variation on it.

  • But that doesn't mean that there isn't still room to innovate on body shape.

  • One thing that I would be curious about is doing a V the other way.

  • So having the tips more closed and the back more open.

  • There's a lot of kind of research on the stability of having that kind of a triangle shape.

  • I would think it would be a very stable configuration.

There's a lot of nerves and excitement

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滑雪(Why ski jumpers hold their skis in a V)

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    joey joey 發佈於 2022 年 02 月 10 日
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