The Spa Francorchamps circuit is an epic track, with the longest lap of the year, huge changes in elevation, plenty of time spent at full throttle and variable weather conditions. It is a true driver’s track: all the multiple winners at Spa have claimed at least one driver’s title each. Here are some of the reasons why…
Eau Rouge is one of the most difficult but most satisfying corners of the entire championship. The drivers arrive at 290kph: the aerodynamic load takes in 1G of vertical compression and 5G of lateral acceleration, putting the equivalent of 1000 kilograms on the front-left tire and 950 kilograms on the rear tire – which has to generate traction all the way around the corner.
At Pouhon the cars reach this demanding downhill left-hand corner with their tires fully up to temperature, leaning on them at a speed of 290kph. There is 4G of sideways acceleration throughout the whole of the bend. The tire’s job is to counteract this force and allow the driver to maintain a perfect line through the corner, even when the car is under acceleration.
In the third sector of the lap, which is fast and flowing, the car is at full speed for a long period of time. The tires have to cope with a vertical load of 1100 kilograms from all the downforce generated. Then, throughout the flat-out corners, the tires counteract 4G of sideways force to maintain the necessary precision that is vital to hold the racing line at more than 300kph.
During the final part of the lap, the drivers brake hard for the Bus Stop chicane, which is made up of tight right-angles, before opening up the throttle again for the start-finish straight.
Lucas di Grassi, Pirelli’s test driver says: “Spa is a real old-style circuit, which is very fast and technical. I love it, and it’s always a huge pleasure to go there. In terms of set-up it’s always a compromise, as you need plenty of straight-line speed but also lots of downforce for all the quick corners. There are several points where you can overtake – after Eau Rouge is a good place, for example – and this is always a circuit where it pays to be brave. For the tires, it’s definitely a challenging race as a huge amount of energy goes through them because of the high speeds and big aerodynamic loads. The other big factor is the weather: from my experience here in the past I would definitely expect to see the intermediate and the rain tires being used at some point during the weekend. Even when it is dry on one part of the track, it can be raining at another place.”
Ecological disposal of the Formula One tires:
As part of Pirelli’s ‘green technology’ program, the Italian company is committed to environmentally sensitive working practices, having started to eliminate aromatic oils from some of its road and competition tires since 2007. Since January 1, 2010, as required by European legislation, all of Pirelli’s road and motorsport tires are produced without aromatic oils.
Part of this commitment also involves the ecological disposal of the tires once they have been used. All the tires are transported back to Didcot after each grand prix, where they are finely shredded, along with other road car tires.
The shredded tires form small pellets, which are then burnt at extremely high temperatures as fuel for cement factories. The extremely high temperatures, in excess of 1400 degrees centigrade, means that no noxious fumes are released and the only particles that remain are very fine, non-toxic, ash.
Pirelli has been using this technology since 2002 in Italy, and also used it throughout its return to single-seater competition last year with the GP2 season. In total, Pirelli will dispose of up to 80,000 competition tires this year using this method – which has been adopted as well in other countries throughout the world.
Pirelli’s motorsport director Paul Hembery commented: “The environment has always been extremely high on our agenda at Pirelli. The way that we dispose of the tires is firm evidence of this: in fact, the road surfaces that spectators drive on to get to grands prix in future could well be made up of some of our recycled tires”
Pirelli Tire North America designs, develops, manufactures and markets tires for passenger vehicles in both the original equipment and replacement markets as well as markets and distributes tires for motorcycles and motorsports. Located in Rome, Georgia, Pirelli’s Modular Integrated Robotized System (MIRS) employs state-of-the-art technology to manufacture tires for both export and domestic markets. For more information please visit www.us.pirelli.com.