Formula One comes to India for only the second time this weekend, and just like last year Pirelli will bring the P Zero Silver hard and P Zero Yellow soft tyres. However, these compounds are softer compared to their equivalents last year, and with a better knowledge of the Buddh circuit plus some real data, Pirelli can afford to be less conservative this time - which should lead to even closer racing.
Compared to the last grand prix in Korea, where Pirelli brought its two softest compounds, India places heavy demands on the tyres. This is due to a number of factors, starting off with the high ambient temperatures in excess of 30 degrees centigrade. The track layout also takes in several fast corners that put plenty of lateral energy through the tyres: in particular the banked turn 10, which is similar to the famous turn 8 in Turkey. The front-left tyre is subjected to an acceleration of 4g on the exit of the corner, where maximum grip is required to hold the racing line, but the tyres are actually under full lateral load for six seconds during the corner, which increases wear.
At the beginning of the lap in particular, there are some notable elevation changes that exert vertical forces on the tyres as well, combined with a braking force of 3.6g into turn 4. The main straight, which is more than a kilometre long, is one of the longest of the year: while tyre tread temperature peaks at over 100 degrees centigrade during the course of the lap, it tends to cool down considerably by the end of the straight.
As the circuit is not used extensively during the course of the year, a high degree of track evolution is expected over the weekend. A dirty track causes excessive wheelspin as the cars struggle for grip: this also increases tyre wear. Generally though, the surface of the Buddh circuit is quite smooth, which means that degradation is contained.
Paul Hembery: "There was an amazing atmosphere and an extremely warm welcome at the Indian Grand Prix for us last year, so we're all looking forward to going back. This year we know a little more about the track so we've made a less conservative choice, with the hard and the soft tyres striking exactly the right balance between performance and durability. The circuit layout is one of the toughest that our tyres will face throughout the second half of the season and it's also the last time that we will see the hard and soft combination this year, which was previously used in Barcelona, Britain and Japan - which gives you some idea about the demands of this circuit. The Buddh circuit has been specifically designed to encourage overtaking, which is also one of the objectives behind the design philosophy of our tyres, so we should be set for an action-packed race at a crucial point in the championship."
There was a performance gap of up to two seconds per lap between the two nominated compounds last year, but this year the gap should be a lot smaller, allowing the majority of the front-runners to get through Q1 on the hard tyre.
The asphalt of the Buddh international circuit was brand new last year, but one year on the characteristics of the surface may have evolved. A new circuit gradually releases oils from within the asphalt, which forms a slippery layer on the track surface. Over time however this film gradually disappears, giving it more grip and making it more abrasive.
The pit lane in India is one of the longest in Formula One at around 600 metres. This leads to a relatively significant time loss when changing tyres, which is an important factor when considering the race strategy.