A Bit of History: The Evolution of Skis

The first downhill skiing competitions began in the 18th century. At that time, the Norwegian army used long planks of hardwood, such as ash, to measure the agility and speed of its soldiers. In the same period, in the Telemark region, the first camber ski appeared, allowing easier turns and giving birth to the Telemark technique still used today.

A few decades later, laminated skis were introduced, combining different types of wood to create lighter, more flexible and responsive skis. Since then, technical development has continued, with skis adapted to each discipline: downhill, giant slalom, slalom, ski cross, moguls, or slopestyle.

Composition: Core, Lamination and Sole

Each discipline imposes different constraints on the ski, and the composition of the materials is chosen accordingly:

• Core: Made of wood (for example ash wood for good rigidity, or poplar for its lightness), foam, or composite.
• Lamination: Fibreglass, carbon, or Kevlar. Fibreglass is ideal for downhill skis, providing robustness and vibration resistance. Carbon films, which are lighter, are preferred for slopestyle or acrobatic disciplines, where manoeuvrability is paramount.
• Sole and edges: To ensure an optimal glide, UHMPE polyethylene (ultra-high molecular weight) is used for the sole, to which specific surface treatments are added to increase durability and grip. Certain types of steel are used for the edges, allowing skiers to grip the ice.

Polymer and Composite Chemistry: Technical Innovations

Chemistry and materials science play a central role in the manufacturing of modern skis, especially when it comes to combining lightness, durability, and performance:

• Resins and fibres: Adhesion between the fibre layers (carbon, glass, Kevlar) and the wood core is crucial. Resins must withstand vibrations, impacts, and temperature variations while maintaining the flexibility necessary for each discipline.
• Multi-layer composites: For downhill skiing, composites enhance longitudinal and lateral rigidity, improving stability at high speeds. For acrobatic disciplines, lighter composites allow for better rebound and shock absorption during jumps and landings.
• Surface and anti-friction treatments: The polyethylene sole is treated to minimize friction with the snow and optimize speed. These treatments are adjusted according to snow type and discipline, directly influencing performance.

Applied Physics: Performance and Behaviour Under Stress

Beyond the choice of materials, each ski must react precisely to the forces generated by the skier and the terrain. Olympic disciplines impose very different constraints:

• Downhill: High speed, wide turns, and icy surface. The ski undergoes significant bending forces and large-scale torsion. The rigidity of an ash core and fibreglass/composite lamination allow vibrations to be absorbed while maintaining trajectory.
• Slalom and moguls: Short turns, quick changes of direction, and jumps. The ski must be flexible to allow quick torsion and impact absorption. The aim is to use wood species such as ash for the core. Using a thin layer of carbon in the laminations reduces weight to facilitate manoeuvrability.
• Ski cross and slopestyle: Combinations of jumps, tight turns, and obstacle landings. Force distribution must be homogeneous, so the ski absorbs shock energy while transmitting enough power to the ground for maximum control.
  

Finally, solid mechanics explain why some skis behave better in certain conditions and how to optimize performance for each course type.

Conclusion: Science and Performance of Olympic Skis

Overall, the design of each ski is a subtle balance between chemistry, physics, and materials engineering to meet the specific requirements of each Olympic discipline.

Que ce soit pour la descente à grande vitesse, les virages serrés du slalom, ou les sauts acrobatiques des bosses et du slopestyle, chaque ski olympique est le fruit d’un travail colossal en amont d’ingénierie et de chimie. 

On the eve of the Olympic Winter Games in Milano Cortina, we wish our athletes every success in making the most of the technology under their feet.

Let’s hope that The nvincible Courage forged through the immense efforts of our Canadian athletes will bring them all the success they deserve!

Go Canada!