“They’re black and they’re round,” that’s Sebastian Vettel's verdict on F1’s new Pirelli tyres, but even the reigning world champion had to concede that the new rubber isn’t like anything F1’s had in recent memory.
The Pirellis degrade quickly, which means the drivers have to make more pitstops and that means (potentially) a lot more drama. With that in mind, we spoke to the man who knows them best, Pirelli’s director of Motorsport, Paul Hembery.
Paul, why haven’t Pirelli produced tyres that perform in a similar way to the old suppliers?
We were given a brief to assist the show! The teams and Bernie Ecclestone wanted to have more tyre changes, more movement and tyres brought into the strategy of the race. On the surface that might seem quite easy: in reality it was easier to make a tyre that would last a whole weekend. We are working to produce a prime tyre that will last about 25 laps – but if we get that wrong and it lasts 45 laps, we are back to the one-stop strategy, and we haven’t provided any difference to the sport.
Pirelli has been very active in WRC and MotoGP, can you draw on that experience, or is F1 very different?
F1 is its own beast, because there is no other formula that stresses its tyres so much, that has the braking these cars have, or the traction and torque coming out of the corners. The physical loads on the tyres are far in excess of anything you would find in any other sport. But having said that, as a tyre maker you have certain design philosophies, and certain approaches to your job. You’ve got to make a product that works of the majority of participants, and provide a level playing field for everybody. So there are elements of how we go about our job that we bring from other categories.
Everyone is talking about the tyres, but maybe not for the right reasons. Would you rather they weren’t such a big topic?
I’d like people to be talking about the tyres for the right reasons. We want the tyre becoming an important strategy aspect. Then we are part of the show. We needed a different approach to what we had in WRC, where we became too good and were taken for granted. We never had any punctures so nobody talked about us. Ultimately, it’s very exciting from a technical point of view to be involved in an open competition, but if you lose, it’s your fault, and if you win, it’s down to the driver or the car. Tyres only get a mention if they have a problem.
We also say ‘new rubber’ – but your tyres aren’t made from rubber, are they?
We have gone with synthetic rubber because you can engineer many different versions of it and that opens up a lot of possibilities. Natural rubber is just natural rubber. The synthetic materials give us an element of forced decay and degradation which increases the number of pit stops. 20 or 30 years ago we might have used these ingredients in search of grip; now we’re trying to find the fun.
How much work did you do to develop the tyres so far?
We did a lot of simulation and a lot of testing: 18,000kms for ourselves, plus the official winter sessions with the teams. That gave us a huge data bank of information about how the product was working. We’re looking at temperature profiles to see the temperature build-up across the tread of the tyre, which gives us an idea of how the tyres are being stressed. And from that, you’re adding to your know-how of how a product works on a Formula One car. And then you come racing to see if your data is correct. And I’d say so far, so good.
Is that it, or will the tyres evolve some more?
We have a parallel development programme that’s looking at 2012. We have an opportunity with the teams to evolve the tyres through the year, and the idea is that if we want to make some changes, then the sport has allowed us to do that. We would bring [experimental] tyres to a Friday session and if we’re happy with it, we can go to the FIA and say these will be the new product, and substitute one of the existing products. That’s an option for us. We may or may not use it.
With some hard race data to look at now, are you where you expected to be?
We’re in a good place. Based on the amount of time we’ve had to work, and the amount of time we’ve had to work with the teams, I think we have to be very happy with the progress we’ve made so far, and we’re learning all the time. I’m quite sure our 2012 tyres will be quite different to what we have now, but the priority this year is to provide a very reliable basis for teams to go racing.