The German Grand Prix from a tyre point of view: Hockenheim, 20-22 July 2012


What’s the story? Pirelli’s latest specification of the P Zero Silver hard tyre was scheduled to make its debut in free practice at Silverstone – before the famous British weather decided otherwise. Consequently, the new hard tyre will now be brought to Germany for the drivers to try out in free practice on Friday. They will have two sets of the new tyre on top of their usual allocation of 11 sets, with the P Zero White medium compound and P Zero Yellow soft nominated for Germany. Hockenheim – which alternates with the Nurburgring to host the German Grand Prix – is one of just three new circuits for Pirelli this year, together with Bahrain and the United States. The Italian tyre firm does have some experience of racing there through the GP3 Series, which it has supplied since 2010, but no P Zero Formula One tyre has ever yet turned a wheel at the track. However, computer simulations of the circuit and mathematical modelling techniques mean that Pirelli’s engineers are well prepared for what they will face over the weekend. Hockenheim – formerly one of the fastest circuits in the world – is now characterised by some long straights combined with a much slower and more technically complex stadium section. This requires a very versatile set-up, and the tyres too have to cope with an extremely wide range of speeds and conditions. Getting good traction out of all the slow to medium speed corners is key to a quick lap, and the tyres play a vital role in this. There are also a number of heavy braking areas, with the tyres having to absorb up to 5g of deceleration forces. Pirelli’s motorsport director says: Paul Hembery: “After a wet Silverstone, we hope to give the drivers the chance to run on the experimental hard compound tyre during free practice at Hockenheim. But the weather in Germany at this time of year can be almost as unpredictable as it is in England: when we were at Hockenheim for the GP3 Series two years ago we saw plenty of rain, although it’s been very hot in the past too. The new hard tyre is not a big evolution, but it has a slightly wider working range, which should make it easier for the teams to get the tyres up to temperature and maintain them in the correct operating window. We’re running them in Friday free practice only as with the championship so finely balanced, we feel that it would be unfair to suddenly alter one of the fundamental parameters that the teams have made a lot of effort to understand and get the most out of. But we enjoy a very productive dialogue with them, and we will always take into account the wishes of the majority. It’s certainly going to be interesting hearing what they have to say about the new tyre, and seeing if their impressions match up to the conclusions that we have drawn from our private testing. Coming to a circuit that is new to us always holds a different challenge, as we don’t have any of our own previous data to compare it with. But the progress that has been made with simulation is incredible: these days you can learn so much about how a tyre will behave on a circuit without even going there. These advanced modelling techniques illustrate just one example of how our Formula One involvement can help to improve our everyday road car product.” The men behind the steering wheel say: Nico Rosberg (Mercedes): “I am very much looking forward to my second home race. It is always something very special for me to come to Hockenheim. I was born close to Wiesbaden and I like this track very much. I think our car should suit it very well. This circuit demands a lot of downforce, which works the rear tyres a lot: particularly when it is hot. Hockenheim is a special track for me because when I was a little boy and my father won the DTM race here I sat next to him on the roof of the car, waving to the crowd. That was probably the moment when I first thought that I wanted to do something similar when I grew up. The atmosphere in the Mercedes grandstand and the stadium section is always something very special. I won many races here in the lower categories, and that’s another reason why I have a lot of happy memories of Hockenheim. So it would be fantastic to celebrate a great result here together with our fans in the Mercedes grandstand. We will give our all to make it happen.” Pirelli’s test driver says: Lucas di Grassi: “My personal memories of Hockenheim are both good and bad: I had the biggest accident of my career here in Formula 3 in 2005 when I touched wheels with another car and went flying upside down over the fence – but I was also twice on the podium in GP2. Unlike the old Hockenheim, the modern circuit is a track that doesn’t have any particular one feature that will push the tyres hard but instead the challenge comes from a combination of factors: there are some heavy braking areas, with lots of energy going through the tyre, and the stadium section relies heavily on lateral grip. You could see some understeer here if the tyres start to wear, but the main limiting factor will be traction – which is very important. A lot depends on the temperature of course and in Hockenheim anything is possible. It’s going to be interesting to see what people think of the experimental hard tyre, which I helped to develop. Unfortunately we won’t be able to compare it to the current hard as this is not nominated for Germany, but I think the drivers will like it: it offers even better traction, particularly if temperatures are at the lower end of the scale.” Technical tyre notes: •    Finding the right set-up that balances both tyre performance and durability is crucial in Hockenheim. If temperatures are high, the rears are especially prone to degradation because of the constant traction demands and relatively high levels of rear downforce. •    At Turn 6, the cars decelerate from 325 kph to 65 kph in just 2.5 seconds, with most of the energy going through the front tyres that have to brake and turn in at the same time. The weight transfer of this heavy braking causes the rear of the car to feel loose, accentuating the natural bumpiness of the circuit. •    The cars run medium to low downforce in order to get the best top speed on the straights: the aerodynamic set-up is not hugely different to Canada. But this can give a lack of grip in the slow and twisty sections. If the car slides too much, this increases tyre wear by creating more friction against the track surface. The tyre choices so far:

  PZero Red PZero Yellow PZero White PZero Silver
Australia   Soft Medium  
Malaysia     Medium Hard
China   Soft Medium  
Bahrain   Soft Medium  
Spain   Soft   Hard
Monaco Supersoft Soft    
Canada Supersoft Soft    
Europe   Soft Medium  
Great Britain   Soft   Hard
Germany   Soft Medium  

Pirelli in Germany: •    Pirelli has two factories in Germany, including a MIRS (Modular Integrated Robotised System) factory in Breuberg, which is capable of producing 10 million tyres per year. Around 80% of the output is for car tyres and 20% is for motorbike tyres. Approximately half of these tyres are sold in Germany, while the other half are sold in Europe. •    Breuberg is also an important training centre as well as a tyre factory: most of Pirelli’s training for new road car tyre engineers and new workers destined for the company’s most highly advanced factories all over the world takes place there. After Milan, it is Pirelli’s second most significant research and development facility. •    The ‘Reifen’ show, held at Essen in Germany last month, is the world’s largest tyre trade fair. Pirelli launched the Cinturato P7 Blue road car tyre there last month and presented the first testing results of Cyber Fleet: a system that transmits tyre data in real time to drivers and fleet managers using electronic sensors and telemetry. Other news from Pirelli: •    Three teams – Williams, Marussia and HRT – participated in the two-day young driver test at Silverstone last week, supplied as always by Pirelli. Finnish driver Valtteri Bottas was quickest for Williams on both days, which used the grand prix circuit on Thursday and the much shorter international circuit on Friday. •    Pirelli recently won the San Marino Rally, the latest round of the Intercontinental Rally Challenge. Former European Rally Champion Giandomenico Basso, from Italy, claimed the very first victory on gravel for the Ford Fiesta Regional Rally Car, using Pirelli’s K and XR pattern tyres. •    Pirelli has been involved in the build-up to the Olympic Games in London, with the Olympic torch passing through the Pirelli Stadium in Burton upon Trent, England, last week. This is the home of Burton Albion football club, sponsored by Pirelli, which has its main UK factory based nearby.