Too smooth: football and the “Knuckleball” problem

Imagine a football (football ball) in your head and you will probably see the cartoon ideal – a rough spherical shape made of polygonal spots that are sewn together, usually in a familiar pattern of black and white. Many balls were made in this direction for many decades.

Finally, however, the technology continued. The footballs became round, smooth and more colorful. This was seen as a good cause, with every new international competition brought shiny new designs with ever favorable performance. That was until things went too far and the new balls changed the game. So the “Knuckleball” phenomenon was worn.

Glatter is better, isn't it?

From the late industrial age, the footballs were traditionally made with leather panels, which were wrapped around a shape of rubber bubble. Since it is not easy to produce a seamless leather ball, balls from individual leather panels were sewn together to create a vague spherical whole. Early designs had only a few panels and were not particularly good at approaching the shape of a ball. They often had large, wide seams that stretched far above the surface of the ball. Larger seams were largely undesirable as they made the ball more difficult. Combs where the panels met could catch their foot and lead to unpredictable behavior.

Over time, there was a desire to create smooth, round balls for professional game. In the 1970s, football designs began to merge a common format. The standard became 12 pentagonal and 20 hexagonal panels, which could be sewn together in a ball for a relatively good approach. This also enabled the construction of a ball with very fine seams, which enabled a more predictable ball that made it possible to control much finer. The format may have been best made by Adidas Telstar, as used in the 1970 and 1974 World Championships. Although it was not the first that the 12-and-20 design used, the layout and the black and white pattern has been engraved in football awareness since then. In fact, Adidas has produced every following World Cup ball since the 1970 World Cup.

For a while it seemed as if the design of football was colonized. Adidas recorded the 32-panel design until the 2006 World Cup when the +team spirit design unveiled. 14 curved panels were used, which were sewn instead of sewn, creating a smooth ball for even more predictable handling. It was also intended that the design would be waterproof to avoid that wet matches were increased. The ball was criticized by some because of its irregular flight patterns, but was largely considered fit for the purpose.

With another successful World Cup in the belt, Adidas continued for the 2010 World Cup. It created the Jabulani, which consisted of only eight spherical panels, which were connected to an ultra-smooth and cohesive ball. If the World Cup ball 2006 was somewhat controversial, the Jabulani was outrageous. The ball was described as “supernatural” because it tends to suddenly change the direction in flight, which liked the striker to a certain extent, but frustrated the goalkeepers without end. Ultimately, however, this tendency was not good to bring balls to the goal. At the 2010 World Cup, only 147 goals were scored, which very few have changed since the competition in 1998.

The problem came to a phenomenon known as “Knuckling”. This happens when the ball drives through the air with little or no shoot. At a certain speed, the seams on the ball tend to interact with the air flow and to channel them so that it creates sudden and unpredictable movements. The term developed for the first time in baseball, but became relevant for football with the development of the World Cup balls from 2006 and 2010, which suffered this phenomenon more often.

The phenomenon became so well known that the NASA scientists took the opportunity to throw World Cup balls into a test chamber to demonstrate the effects in the game. The ankle behavior tends to reach a high point at a certain critical speed, the effect reduces both sides of the peak. The problem was that the smoother designs “ankle” with higher speeds than balls from earlier generations. The NASA researchers found that due to the ankle, the Jabulani are unpredictable at a speed of 50 to 55 miles per hour – exactly at the speed with which professional strikers can deliver a ball into the net. In the meantime, more traditional 32-panel balls tend to see a climax in a ankle of about 30 miles per hour. Since strikes usually went beyond this speed, the ankle – and thus the unpredictable flight – was not a problem with the older designs.

Adidas was well aware of the problem after the 2010 World Cup and returned to the drawing board and developed the Brazua for the 2014 competition. The number of panels was further reduced to just six. However, Adidas didn't want to be smoother again. Instead, the Brazua had longer, deeper seams than the Jabulani and panels that were covered with structured bumps. Due to the careful design efforts of the company, this brought the critical ankle speed back to around 30 miles per hour, much more similar to a traditional 32-panel ball.

On the whole, the Brazua proved to be far less controversial than its two predecessors. If you are looking for articles on Ball 2014, you will find a little speculation in front of the World Cup before history has died as soon as the competition began. There were no longer unpredictable balls that confused the best footballers in the world. In the meantime, democratic, whereby the +team spirit and Jabulani have spilled hundreds of words on Wikipedia about controversy and criticism, the Brazza has no.

The history of Jabulani is one of the unintentional consequences. Adidas had intended to improve his product in a predictable and routine way just to find an unexpected effect when playing that threw a wrench in the works. As soon as the effect was understood, it could be checked and refined with careful design. Since then, football has not suffered a “supernatural” ball, even if the technology continues to march into the smart ball era. Who still knows what will come next at the 2026 World Cup?