The teams are now making their final preparations in Melbourne for Pirelli’s return to Formula One. The Albert Park circuit is one of the most complex of the entire Formula One calendar.

Having brought the hard and soft compound PZero rubber to Melbourne (as the prime and option tyre respectively) Pirelli is expecting two to three pit stops per car in what should be an action-packed race.

The Italian firm explains the reasons behind the choice of the compounds below, and reveals the  highlights of a track that traditionally springs a few surprises.

THE TYRES
The choice of the hard tyre, which is the most durable PZero compound, was influenced by the characteristics of the Albert Park track, which combines a medium aggressive surface with constant changes of elevation, speed and direction. For the same reasons, the soft tyre has been chosen too.

THE TRACK
The Albert Park circuit, which is 5,303 metres long and takes in 58 race laps that total 307.574 kilometres, is home to a wide variety of conditions on a surface that is not greatly rubbered-in. This has a profound effect on tyre wear. Another important factor governing tyre wear is the comparatively high level of downforce used, which is necessary due to the quick succession of corners and absence of long straights.

Yet another element that affects both tyre wear and stress on drivers and cars is the kerbing, straight after the start into the first braking area. Here, the drivers have to judge their turn-in point carefully so that they do not destabilise their cars by taking too much kerb.

A place where the tyres and cars are worked especially hard is the Sport Centre corner. The drivers scrub off 200 kilometres per hour in just 2.5 seconds and 108 metres under braking, subjecting themselves to a 5G deceleration while the front tyres are pushed into the ground by 1150 kilograms of downforce.

Shortly afterwards there is another challenge: a long right-hand corner that is taken flat-out, with slippery asphalt that can provoke oversteer and therefore tyre wear.

The drivers then enter the most technical part of the circuit, which is also the most demanding: a blind bend taken at around 250 kilometres per hour, where it is important to stick to the part of the circuit that is most rubbered-in so as to take maximum advantage of the grip available. This is part of an S-bend complex, with bumpy asphalt that can destabilise the car. Being only a semi-permanent facility, the track has very little rubber on it at the start of the weekend on Friday, which has an inevitable effect on tyre performance.

Waite corner is one of the key points of Albert Park. The exit speed from the corner is in the region of 210 kilometres per hour. The stressed front tyre (on the outside of the curve) is operating at around 105° centigrade, whereas the inside tyre on the right has slightly less work to do and runs five degrees cooler at around 100° centigrade. The rear tyres, which provide the traction, operate at temperatures in excess of 100° centigrade.

Another important area is the braking zone between turns 14 and 16, which loads the front of the car heavily leading into a chicane with tight right-angle corners before the main straight: the only place on the track where the cars top 300 kilometres per hour in seventh gear, and a key overtaking opportunity.

The size of the tyre’s contact patch with the ground varies according to speed and aerodynamic load. At 300 kilometres per hour, the contact patch of the tyre is around three times what is when stationary, offering optimal traction and grip.

PIRELLI’S MOTORSPORT DIRECTOR SAYS:
Paul Hembery: “We’ve worked hard for more action together with all the teams and now we can finally get going. It wasn’t easy to find the best balance in terms of tyre degradation, which would promote pit stops and enhance the show as we were requested but at the same time ensure that the tyres did not deteriorate too rapidly or too slowly. In GP2, where the cars and the tyres are quite similar to Formula One, it was a lot simpler. The teams asked us for structural reliability rather than variable degradation and after the first few races we know that we have come up with a long-lasting tyre that everybody likes. What’s certain is that our PZero Formula One tyres are structurally extremely reliable and can guarantee safety. The degradation is not immediate, but it is enough for the driver to feel a gradual drop off in performance over the course of a stint and then decide whether to change tyres or not. This is where strategy comes into play. In Australia our target is to see between two and three pit stops per car”.