““Soccer is not a matter of life or death. It is more important than that.”Bill Shankly
Bill Shankly, former manager of the Liverpool Football Club and author of the above quote, exemplifies the passion and downright lifestyle that many soccer enthusiasts have around the globe .
Soccer Ball Aerodynamics
Stitching can further disrupt the smooth air flow from the front of the ball to the rear of the ball and aggravate the turbulence experienced on the surface of the ball. To reduce the unpredictability that stitches can introduce in a ball’s trajectory, the Jabulani uses only eight panels (as opposed to the traditional soccer ball’s 32) which are then thermally bonded, ensuring that no stitching is used to bind the surface. Fewer panels also means a smoother surface (Fig. 3).
An incredible round ball, however, has its drawbacks. Simon Choppin, a sports engineering researcher at Sheffield Hallam University, explains that a typical soccer ball has a dense, uniform seam pattern which yields a relatively rough surface . This type of ball does not bounce or roll as consistently as a smoother one, but the airflow around it becomes turbulent almost all at once, resulting in less differentials in air pressure, leading to a smoother, more hyperbolic trajectory.
This is why certain free kicks in soccer will unexpectedly dip or sway after being in the air for a few moments—the ball is initially hit from around 70 MPH, and, as it slows down, the velocity eventually falls below the critical 20-30 MPH zone, leaving the turbulence threshold and entering the laminar threshold. The ball suddenly slows down a lot more rapidly, enough to affect the trajectory . A video of this very principle can be seen in a famous David Beckham free kick during a 2001 World Cup Qualifier match against Greece on the YouTube website . All spheres experience this, and the Jabulani was no exception.
The slower a ball travels with the same amount of spin, the more it will curve. This, coupled with a unique characteristic of the Jabulani, is what made the ball so unorthodox in terms of flight characteristics.
NASA and the Jabulani
-  T. Asal. “The Physics of Football.” Physics World 1 June 1998: 25. Print.
-  “Adidas ‘JABULANI’ Official Match Ball of the 2010 FIFA World Cup.” Loughborough University, 4 Dec. 2009. Web. 20 Oct. 2010. lboro.ac.uk
-  S. Davis. “More Jabulani Match Ball Chat, Now From a U.S. Player Perspective.” Daily Soccer Fix, June 15 2010. Web. 18 Oct. 2010. dailysoccerfix.com
-  “Maradona takes another kick at Jabulani ball.” Deccan Herald, 23 June 2010. Web. 21 Oct. 2010. deccanherald.com
-  “World Cup 2010: David James Criticises Jabulani Ball.” BBC.co.uk. British Broadcasting Company, 2 June 2010. Web. 27 Jan. 2012. http://news.bbc.co.uk/sport2/hi/football/world_cup_2010/8716699.stm.
-  T. Azzoni. “Adidas Shocked at Criticism of World Cup Ball.” NBC, 31 May 2010. Web. 18 Oct. 2010. nbcsports.msnbc.com
-  T. Chartier. “Bending a Soccer Ball with Math.” Davidson: Davidson College, 2010. Print.
-  E. Covert. Thrust and Drag: Its Prediction and Verification. New York: American Insti-tute of Aeronautics and Astronautics, 1985. Print.
-  “Drag.” The Internet Encyclopedia, n.d. Web. 20 Oct. 2010. daviddarling.info
-  S. Choppin. “Jabulani, a Ball in Crises?” Engineering Sport: The Centre for Sports Engineering Research, 25 June 2010. Web. 20 Oct. 2010. engineeringsport.co.uk
-  “Beckham Free-Kick Vs Greece.” YouTube, 7 Apr. 2006. Web. 18 Oct. 2010. youtube.com
-  R. Marlaire. “NASA Scores Big With Student Soccer Players in the U.S.A. and Canada.” NASA, 16 June 2010. Web. 20 Oct. 2010. nasa.gov
-  “World Cup Ball: What’s Wrong With It?” Discovery News, 30 June 2010. Web. 24 Oct. 2010. discoverynews.com
-  “FIFA Admits Problem with World Cup Ball.” The Final Third: Men’s Soccer Lifestyle Magazine, 26 June 2010. Web. 20 Oct. 2010. thefinalthird.com
-  “500 Days: Time to Mobilise a Nation.” FIFA, 26 Jan. 2009. Web. 21 Oct. 2010. FIFA.com
-  S. Barber, and M. Carre. Computational Fluid Dynamics for Sport Simulation (Lectures Notes in Computational Science and Engineering). Germany: Springer-Verlag, 2009. Print.