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History of the Wear

©1993 NAOC TM NAOC 7-056

Faster, Farther, and Safer than A Sweater


Development of Ski Jump Wear

The story of Japanese ski jumpers getting the triple medals of gold, silver, and bronze in the normal hill at Sapporo Olympics (1972) is often told even today.

At the time of Sapporo Olympics, ski jumpers, Alpen skiers, and also skaters wore the sweaters and the pants.
Since then “the faster, the farther, and the safer wear”, has been developed and improved.



From One Piece Suit to Five Layer Texture


History

One-piece suit appeared in the late 70s.
Elastic two-way tricot (cloth used with a swimsuit) was used and a feeling of wearing improved drastically.

In the 80s, the scientific technique such as the wind tunnel experiment began to be used for development. The suit texture which reduced surface air resistance was developed.

Furthermore,in the1990s, texture of 5 layor structure is developed and used nowadays.


⋄ Directions of force applied to the ski jumper
Increasing the lift and decreasing the drag results in distance improvement.



Wing Suit, Baloon Suit — 1970s


Regulation for the ski wear

Various trials for the development of the suit was done in the late 70s.
For example, the suit which has wings between the arms and the body (so called wing suit) or the suit which has large breathability in the front texture and small breathability in the back region, keeps the air in the suit and stays in the air longer (so called baloon suit) was invented.

However, the International Ski Federation (FIS) came to establish the regulation for the safety of the skiers and the equity of the competition.
All such suits were forced to change.

The rule of FIS says:

  1. The breathability of the material (the quantity of air that the suit cloth lets go through) must be
    more than 40 liters per 1 square meter a second with the ski jump suit.
    With Alpen ski suit, more than 30 liters.
  2. The suit must be made from a single texture and the whole consists of the same material.
  3. The material must have 8mm or less thickness.

Accoring to the regulation, various original and unique suit production came to be limited.



How to Fly Longer Distance — 1980s


Jump suit in 1980s

The development of the suit aiming at flying distance improvement began in the 80s.

That figure 1 (see page1) shows the directions of the force on the ski jumper.
To fly longer distance, important factors are:

  1. lightweight ⋅⋅⋅ suit material must be light.
  2. great lift force ⋅⋅⋅ moderate space ratio between the suit and the body (porosity).
    Keep some hardness to material and avoid the flapping of the wear.
  3. minimum surface resistance ⋅⋅⋅ smooth off the material surface.

Picture 1 shows both the new texture of minimum surface resistance and the normal resistance texture



Victory with Wind Tunnel Suit


Scientific suit

Picure 2 shows the wind tunnel experiment.
The jump suit was tested measuring the drag and the lift to improve the flying distance.
Jens Weißflog, 19-year-old East Germany jumper, won a gold medal with this type of suit in Sarajevo Olympic Winter Games in 1984.



Suits in Nagano Winter Olympic Games —1990s


Jump suit in the 1990s

The flight style changed to V-shape, and the demands on suit function changed.
The suit that keeps its shape against the wind pressure, and is light and also elastic was wanted.
However, with single texture, it was impossible to make the suit satisfing all these demands . Conbination material was developed.

The texture in figure 2 was deviced through the wind tunnel experiment of flying capacity and wearing fitness.
The material of the same structure is used in Nagano Olympic Winter Games.



Jump Suit applied to Skating and Alpine Skiing suit


Skating suit

Material developed for a jump suit in the 1980s was also used for a skating suit and Alpain ski suit.
The soft feeling and high elasticity are welcomed by the athletes. Many of them said that the new wear is confortable and free from the wearing pressure.

1990s attracted attention how to reduce the form drag of skating suit.
Two types of air resistance :

  1. surface resistance — smooth the surface using very thin fiber with small resistance
  2. form drag — add a line-formed silicon projection to the part where the surface air exfoliates and produce resistance

Photograph 3 shows the suit enforced by (2) and was actually used in Albertville and Lillehammer Olympic Winter Games.



Minimizing Air Resistance


Alpain ski suit

Alpine ski suit which wraps the body tightly and reduces the air resistance was developed in 1990s.
The suit material has three layor structure with polyurethane elastomer in the middle.