Managing tyres at Spa-Francorchamps takes ‘special skill’ – Pirelli
Former Formula One racer Jean Alesi has emphasised the importance of tyre management at the Belgian grand prix. Held at one of the quickest circuits of the season in Spa-Francorchamps, Pirelli’s brand ambassador said that the number of fast corners, combined with the length of the track and variable weather could mean that the tyres cool during the latter stages of the lap, making achieving even performance throughout the lap difficult. The exclusive tyre supplier is bringing the P Zero Orange hard and P Zero White medium tyres, the two hardest compounds in the range, to Spa – an allocation that Pirelli says is “perfectly suited” to the high-energy demands of the circuit. Inclement weather could bring the Cinturato Green intermediate and Cinturato Blue wet tyres into play too.
Alesi said: “Spa is a circuit that everyone talks about and over the years I’ve not heard anybody say anything apart from the fact that it is awesome. It’s so fast and so challenging, but one of the key characteristics is the fact that it’s very long. So it’s never monotonous, as you do very few laps compared to other tracks. Managing the tyres takes a special skill: there are lots of fast corners and the length of the track as well as the variable temperatures mean that your tyres can actually cool down after the first part of the circuit. But in qualifying, if you start off with your tyres too warm, then you won’t get the maximum performance from them throughout the entire length of the lap.
“There’s a huge amount of variation possible in terms of set-up as well: some teams add downforce to get more grip in the mid part of the lap, and that will also have an effect on how the tyres work. Probably the most important characteristic is the high possibility of rainfall. You can have a completely dry corner and then a fully wet track a few corners later. Underneath the water though, the surface is quite abrasive and offers good grip, so you can still drive. The bigger problem is the sudden rivers of water that run across the track in a zigzag shape: you’ve got to know where they are, so that the aquaplaning doesn’t catch you out. There’s also a lot of spray at Spa when it rains, which makes visibility very difficult in wet conditions.”
Spa has been part of the Formula One world championship since it got underway in 1950, though the track changed radically before arriving at its current layout in 1979. The fast and flowing 7km lap – the longest of the season – has an average speed in the region of 230km/h. Cars are on full throttle for around 80 per cent of the lap, sometimes for more than 20 seconds at a time. Pirelli suggests that this makes qualifying performance less important than it can be on other circuits.
At high speeds, aggressive camber angles can cause blistering as heat builds up around the edges of the tyres. However, Pirelli has given the teams maximum recommended camber angles, which should help prevent this phenomenon. The big compression at Eau Rouge subjects the front tyres to the highest vertical load of the season: 1,000kg.
Button and Vettel – first and second last year – used a one-stop strategy, while third-placed Raikkonen stopped twice. Most drivers started on the medium tyre, but Hulkenberg’s fourth place finish starting on the hard tyre with a two-stop strategy, showed that different strategies can be successful. Pirelli predicts a performance gap between the hard and medium tyre of more than a second per lap.
Motorsport director Paul Hembery added: “Spa is not only an epic circuit, but also one of the biggest challenges for our tyres all year. Mostly this is because of the very high-energy loads that go all the way through the tyres, both vertically – due to the big compressions such as Eau Rouge – and also laterally at fast corners like Blanchimont. Often, the tyres are subjected to forces acting in different directions at the same time, which increases the work still further. So looking after the tyres is very important, particularly as it’s such a long lap.
“This means that there are a very wide variety of possible strategies available at Spa as well, with plenty of time to be won and lost if the right tactics are chosen. However, any strategy has to be very flexible, because it’s the changing weather that often makes Spa such a fascinating race. The conditions can change extremely quickly, which then makes how the teams use the intermediate and wet tyres the key to success – as we have seen so often in the past. Both our wet-weather tyres have proved their performance over previous races; with the intermediate tyre in particular showing how well suited it is even to inconsistent and drying conditions. There are plenty of overtaking opportunities, and the blend of performance and durability offered by our nominated tyres should maximise those chances this weekend.”
Pirelli’s last outing in Spa was at the Spa 24 Hours last month. This was one of Pirelli’s biggest-ever logistical operations, with 8552 tyres available on site, transported by a convoy of 19 trucks. The fitting service delivered a tyre every 26 seconds on average (over a 22-hour period).
Alguersuari, di Grassi ‘high calibre’ testers
Pirelli says that it has been able to rely on two high calibre test drivers this year in Jaime Alguersuari and Lucas di Grassi. Alguersuari completed the first two tests in 2013, while di Grassi is scheduled to take over later this year.
Their work consists of assessing the latest experimental compounds from Pirelli during private tests, driving a 2010 Renault that has been modified to replicate the latest regulations. Once they have driven on the prototype tyres, they give their feedback to Pirelli’s engineers about each compound’s characteristics and how the tyres could be improved for the future. The use of two test drivers ensures that the engineers get two different perspectives and opinions: essential when tyres are being developed for a grid of 22 drivers.
Alguersuari became the youngest driver to start a Formula One race when he made his debut in 2009, then he completed two further full season with Toro Rosso before becoming a Pirelli test driver, with a best result of seventh in Italy and Korea in 2011. As well as a skilled racing driver, he is also a talented DJ, topping the charts in Spain.
Meanwhile di Grassi drove for the Virgin Formula One team during its debut season in 2010, taking the car to 14th in Malaysia. He joined Pirelli in 2011 and is also a factory Audi driver in endurance racing, finishing on the podium at this year’s Le Mans 24 Hours.
More testing has been completed on Pirelli rubber recently by Lotus driver Kimi Raikkonen, who tested a GP3 car last week. The Finn tried out the car in Barcelona during an official development test. “The GP3/13 is a very good tool for young drivers, especially when you have to learn about tyre management like we have in F1,” he said.