Ski Jump —Why V-style flies father? —

©1993 NAOC TM NAOC 7-056

History of V-style Jump

History of V-style ski jump

Most of the ski jumpers fly in the V-style recently.

In 1992 at Albertville (France) Winter Olympic Games more than half ski jumpers kept their skis parallel after the take off.
However in 1994 Lillehammer (Norway) Olympics found all the ski jumpers competing in the V-style.
Why can the V-style fly further? How was the V-style proved to be better style?

Here is an introduction of the research conducted in Japan.

Characterisics of bird's wing

How can birds and airplanes fly?

They both have wings and the shape of the wings has the secret to fly well.
Watching the wings, you may find the front part is thick and the rear part is becoming gradually thinner.
Careful watcher may know that the front top is the thickest. This shape produces the lifting force and pulls the wings upward as they go through the air.

Spread the wing and catch the air

Why does the V-style fly further?

The shape of the wings of a flying bird relates to the V-style.

Imagine a seagull or a kite flying easily in the sky.
With its wings widely open, it can hold a lot of air and get the lifting force which can keep it in the air. The same thing happens when the skier opens the skis widely.

Wind tunnel experiment

Wind Tunnel Experiment

Human size doll wears the skis, helmet, gloves, ski jump suit, and goggle just like a real ski jumper.

The wind tunnel is operated so that the doll gets as strong wind as in the real ski jumping situation.

Experimental Condition:
The force that the human size doll receives from air stream is measured using the similar equipments as the real ski jumpers.

Wind Tunnel Feature:

  1. size: 3 meters in diameter
  2. wind velocity: 50meter/sec (180km/h)
  3. elctric moter: 500 horse power

⋄The experiment was performed in Research Center for Advanced Science and Technology at Univ. of Tokyo

Idealistic jump

What is measured in the wind tunnel?

The lifting force produced by the wind is measured as well as the air resistance.
Idealistic V-style is then calculated. The best V-style form was estimated in this way.

⋄Prallel Style Mesurement
The picture shows the experiment of parallel style ski jump.
The arms of the skier are widely open from the body in this picture.
However better performance is obtained when the skier keep their arms tightly at the side of the body.

Wind stream and swirl

Smoke Wind Tunnel Experiment

The smoke wind tunnel helps you to see the air stream.
You can find the turbulence and the whirl of the air. The smoke helps to find the idealistic V-style.

Ski jump doll finds the ideal V-style

V-style ski jumper doll in the wind tunnel

The doll's legs are opened in various degrees in the wind tunnel. The influence of the open legs is tested.
The angle between the skis and the body was also measured to find the idealistic form of the V-style.