What's all the Pirelli fuss about?
There are at least two bones of contention, but the one grabbing the headlines recently has been about changing the specification of the new-for-2013 tire after only six races. Red Bull Racing has been pushing to have it changed for something more robust; most of the other teams don't want that because they feel a more robust tire would play to Red Bull's advantage. Initially, Pirelli was adamant that it would not change, but then in the aftermath of the Spanish Grand Prix, it said it was going to introduce a “new” construction for Canada, two races later. However, it will only be a minor tweak, following the FIA's clarification that tire specs could only be changed for safety reasons. Pirelli has been instructed to solve the matter by modifying the current specification of tires.
So Pirelli caved in to Red Bull?
No. The change was considered because the 2013 tires around the punishing Barcelona track caused most cars to do a four-stop race – and Pirelli doesn't like four-stop races because it sends the wrong marketing message regarding its tires' durability. It's felt that two/three stop races are acceptable. There has also been the issue of rear tire treads unwrapping themselves from the carcass when they are damaged, giving a very visible failure that sends all the wrong messages to potential Pirelli customers in the street.
But regardless of what led Pirelli to want to change, the change would favor Red Bull?
A change to a tougher tire would probably help Red Bull, yes, particularly a tougher front tire. According to Pirelli itself – which sees the data from all the cars – the Red Bull RB9 has so much more fast-corner downforce than the others, it would be dominating every race if the tires didn't apply a certain equalizing factor. A more robust tire would allow more of the Red Bull's potential to be accessed.
So how does a tire do that? How can a tire prevent the fastest car being the fastest when they are on all the same tire?
By having a tire that cannot support the forces generated by the fastest car. The Pirelli tires are unusual in that, beyond a certain point, the faster you go, the faster you destroy the tire and this has been apparent at the more demanding fast-corner tracks ever since Pirelli first came in as the F1 control tire supplier in 2011. Teams with the fastest cars have often had to take downforce off them – actually making them slower – in order to find the optimum trade-off between outright speed and the stint lengths necessary for the best stop strategies. It has had the effect of bringing the very fastest car back down to the level of being merely competitive, applying a certain artificial leveling.
So why is it a big thing all of a sudden this year?
Because for 2013 Pirelli introduced an all-new construction which has proved more extreme. It felt that the sequence of one-stop races we had toward the end of last year indicated that teams had now got on top of the challenge of the tires and had found a way of getting durability. Pirelli says that part of the task it accepted when it was chosen to supply F1 was to ensure unpredictability by having multi-stop races. It doesn't therefore like one-stop races but – for the reasons already explained – it doesn't like four-stop races. In order to hit the two/three-stop target, Pirelli felt it needed to introduce a tire that was more challenging for the teams to make last. It has certainly succeeded in that.
So some teams have adapted to it better than others?
Yes. Essentially the same traits as before have been amplified. The Lotus and Ferrari were already good on tire usage last year. Red Bull was less so, Mercedes even worse. On the 2013 tire, the Lotus and Ferrari race day advantage over Red Bull seems to have increased on any tracks where the generic limitation is the outside front tire – this was apparent in both China and Barcelona, the two front-limited tracks we've had so far, and exaggerated in Barcelona by the faster corners.
But the Red Bull is still fast. It has won two of the five races up to Spain.
Yes. It's simply that it is not as fast as it would be were the tires able to withstand higher downforce loads without wilting. And it appears that on tracks like Barcelona with lots of long, high-speed corners, the Lotus and Ferrari have more usable performance over a race stint.
So Lotus and Ferrari have been rewarded for having designed cars with Pirelli tire usage in mind rather than the best theoretical high-speed downforce?
Actually, It's not clear that they have "designed" their cars with that in mind rather than simply stumbled onto it! Here's what recently departed Lotus technical director James Allison said of his car's easy tire usage last year:
“Certainly, suspension design and getting the suspension to work well with the tires have always been priorities with us and perhaps we have paid more attention to that than other teams, I don't know. But no, we have certainly not put a ceiling on the downforce we are trying to achieve with the car. We are always trying to maximize that. No one knows how all the different cars work. You just hopefully have a good idea of how your own works and then you see how that compares on the lap time when you get to the track.”
So Lotus, by its own admission, has got as much downforce as it could possibly find and Red Bull, by Pirelli's admission, has a lot more. Rather than having been cleverer than Red Bull in understanding the demands of Pirelli tires, it's more a case of the traits of the Pirelli tires happening to have come toward the already existing traits of the Ferrari and Lotus, rather than those of Red Bull. That was already the case but, with the 2013 tires, it would seem even more so.
So you could say then that the Pirellis in general have rewarded technical mediocrity and punished excellence?
That would be a very provocative way of expressing it.
Regardless of how intentional it was, shouldn't Ferrari and Lotus be rewarded for having cars better suited to the tires that were provided? The tire specifications were given to everyone at the same time, after all…
Perhaps, yes. But, as we've already said, the motivation for Pirelli changing the tire spec from Canadian Grand Prix onward is not to help Red Bull. That is the last thing it would want to do. It is simply that the answer to the problems Pirelli believes it faces – too many pit stops at Barcelona and four very visible tread unwrapping incidents at Bahrain and Barcelona combined – happen to be an answer that inadvertently might help Red Bull (and Mercedes) and “punish” Lotus and Ferrari.
You mentioned two bones of contention. One is the fuss created by Pirelli announcing it was going to change the spec just six races in. What's the other?
The other is the dawning realization among fans that the Pirelli-era racing is not actually racing as they thought they were watching. Fan opinion is split on this, but there are still those who believe, for example, that Fernando Alonso's impressive Spanish Grand Prix victory came from a display of pummeling, flat-out driving. It did not; in his best stint, even he was lapping 2.4 seconds off his potential pace. It's just that 2.4sec off the pace was faster than anyone else could afford to go in the race.
Alonso's qualifying lap was 1min21.2sec. The cars use around 5.3lbs of fuel per lap around Barcelona and every 22lbs of weight costs around 0.35sec there. At the beginning of his second stint, Alonso will have been carrying around 298lbs of fuel and by the end of it, 12 laps later this will have dropped to around 231lbs. The average fuel weight during that stint was therefore around 264.5lbs. That accounts for 4.2sec per lap (0.35 for each 22lbs x 12 lots of 22lbs). Add that 4.2sec onto his low-fuel qualifying lap and you get 1m 25.4s. His average during that second stint – which was a faster average than anyone else completed a stint in – was 1m 28.8sec, 3.4sec slower.
But part of that qualifying lap time will have come from the approximately 1sec per lap boost you get from a brand-new tire, but which then immediately fades. So Alonso drove the fastest stint of his race approximately 2.4sec per lap slower than he could have done had he not been trying to stretch tire life to get the stint length necessary to stop “only” four times!
Is that bad?
Not necessarily bad, just not what a lot of fans believe they are watching. Formula 1 has always been about all-out performance whereas this is more the type of driving that used to be associated with long-distance endurance racing. In endurance racing now, the cars and tires of the top teams are so good that their drivers have to go flat-out the whole way to stand any chance of winning – just like it used to be in F1. Which is kind of ironic…
But even if it's a different sort of racing we are seeing in F1 now, it's still racing isn't it?
Is it? It is still a competition to see who can get to the end in the quickest time, even if the quickest time does mean driving at least two-and-a-half seconds off the pace around Barcelona in order to make the tires last. But many believe that racing should be about more than just that; it should be about drivers going wheel-to-wheel with each other, about the skills of passing and the counter-skills of defense. And even if a pass doesn't happen, the fact that two drivers are fighting – one trying to pass, the other trying to prevent it – defines it as racing.
But there's lots of passing now…
No. There are lots of place changes, some of them even happening out on track. They look to the casual eye like passes but in many cases they are not – the driver being passed has not defended. Because he knows, or has been told by his team over the radio, that he cannot afford to race the other car because that will eat into his tire life and blow the strategy.
Because the two cars are on different strategies?
Only sometimes. It even happens to cars on the same strategies. At Barcelona, as Kimi Raikkonen's three-stopping Lotus was chasing down the Red Bull of Sebastian Vettel who was trying to three-stop, Vettel's engineer came on the radio to tell him not to race the Lotus, to just allow it past and to continue lapping at the pace that would keep the Red Bull's tires alive (a slower pace than that necessary to keep the Lotus' tires alive). So there was a place change, but it can't be called racing if the guy being passed has chosen to offer no resistance! The performance order of the cars over one lap of qualifying tends to be different from the performance order of them over a race stint (because of the variance in how hard each car uses its tires) and so there is a natural playing out of order changes in the race.
But you'd see order changes if you stood at the side of a busy freeway. That's not racing.
Exactly. Although, again, that's a very provocative way of putting it. You might say it's racing in the long-term sense (that is, trying to get to the finish before the others) but not necessarily in the moment of it (in other words, passing might not actually be defended).
Can the driver influence how fast his tires are degrading or is it all about the car?
He can influence it only by driving to whatever lap time has been found to be the most efficient trade-off between speed and stint length. For Alonso's Ferrari at Barcelona, that was 2.4sec off the pace, for Nico Rosberg's Mercedes it was 4.5sec off the pace. That 2sec difference dwarfs any difference that a subtle difference in technique might make. It's almost all about the car.
In qualifying, do we still see F1 drivers on the limit?
At most circuits, yes. At somewhere with long, fast corners like Barcelona, no. There, the long Turns 3 and 9 put so much heat into the tires if you attacked them fully that your rear tires were too hot by the time you got to the slow-speed acceleration zones in the final sector. There's more lap time to be found in the slow sections than the fast, so the switched-on drivers had worked out that the fastest lap time came from not going flat-out through the two long, fast turns.
Before the FIA insisted last week that the tire specs could only be “tweaked,” what was Pirelli's plan?
It was believed that Pirelli would revert to the 2012 construction for the rear tire, but retain the existing construction for the front. This will reduce the rear tire's propensity to suffer heat degradation. Heat degradation is simply the measure of how much the tire's performance degrades through its structure becoming too hot. They are designed to work in equilibrium at a range between 100-150 degrees Celsius (212-302 F). Get them above that and the performance drops off massively as the tire's internals soften and can no longer support the loads placed upon them. The tire doesn't actually wear out, but just becomes so much slower it's not worth keeping it on. Even the driver backing off cannot bring it back in less time than it would take to visit the pits and have a fresh set fitted (around 20-25sec, typically).
The 2013 tire is essentially a radial construction and the 2012 tire was a cross-ply. The internal plies – longitudinal and lateral – that make up the core of the tire cross at 90deg to each other in a radial. But in a cross-ply there is much narrower angle than that. The longitudinal plies control the movement of the tire under braking and acceleration. The lateral plies control it under cornering load. With the two types of load controlled more strongly in the radial, the core of the tire is inherently more rigid. The less rigid core of the cross-ply requires a very strong sidewall to contain the movement of the structure.
A radial can have a much more flexible sidewall. This allows a steel belt to be fitted between the carcass and the sidewall that separates the movement of the sidewall from that of the core of the tire. In this way, the footprint of the tire (its contact patch) remains much more securely planted, as the flexing sidewall is accepting some of the load that's otherwise trying to break the contact patch's grip with the pavement. But this does allow you to get greater combined braking/cornering grip and if your compounds are not up to it, that will tend to make the tire hotter.
Pirelli has a mix of normal tire compounds and non-gripping chemicals in its rubber (in order to create heat degradation, in order to have multiple stop races) and the increased combined braking/cornering of the 2013 construction has overwhelmed this rubber more easily. The big problem for Pirelli is that the steel belt-type construction means that when the tire gets damaged, instead of just getting an instant puncture like with the 2012 construction, it just puts a stress load on that part of the tire until it breaks and the tread unravels itself from the carcass – very visibly and dramatically in front of all those potential Pirelli customers watching the “race.”
HOW DID WE GET HERE? WAS IT DELIBERATE?
Only partly. When Pirelli bid for the contract, we'd just had the 2010 Canadian Grand Prix where Bridgestone had brought an option tire that turned out to be way too soft – and it created a randomly chaotic race very different from what was then the norm. The feedback from fans was such that the teams and F1 promoter Bernie Ecclestone together asked Pirelli to produce tires that would replicate that. Pirelli was only doing what it had been asked. But in order to get such multi-stop races, it has been necessary to create tires on which you cannot race flat-out and on which the fastest cars are penalized.
In other words, there has been a lot of unintended consequence to meeting the original brief.