After facing stern criticism for its findings after the investigation triggered by the tyre blowouts of Lance Stroll and Max Verstappen in Baku, Pirelli has come out and clarified things a little more where it seemingly claims that both Red Bull and Aston Martin were running lower tyre pressures during the race than prescribed which resulted in the sidewall of the tyres collapsing.
What happened in Baku is simply that the running conditions expected were different compared to the actual running conditions - and that created the failure," said Pirelli motorsport boss Mario Isola.
"When you have a lot of energy going into the tyres, with the pressure that is lower compared to the expectation, the result is that on the sidewall you have what we call standing waves. Standing waves are putting a lot of energy into the inside shoulder of the tyre. And at a certain point, the tyre breaks. That is what happened, and the reason why we had this situation in Baku," he added.
Isola further explained the crashes stating that the expected loads from the simulations were not the values that it found on the track. He added that the tyre pressures Pirelli had assumed and taken a margin for, wasn't what was found on the tyres of the cars which crashed.
Mario Isola is Pirelli's F1 boss who is taking a lot of the flak for the issues
"We assume that they are running at a certain pressure, and a certain camber. And with a margin on it, of course, we run in a condition that is okay for the tyre. In that case, we didn't achieve these conditions, not because teams were doing something against the regulations, but because they were looking as usual for performance, and that created a different scenario to what we were expecting. And the different scenario was that mainly the tyres were running at a lower pressure compared to expectation, " he explained.
While doing so he was careful to note that the team had not done anything wrong against the regulations, but all these explanations almost caused a mini-revolt in the pit lane as there were rumours of the drivers wanting to boycott the driver briefing. Pirelli had intended to join them for the briefing to allay their concerns.
The Red Bull and Aston Martin, the two teams involved in the crashes, came out against what Pirelli had insinuated. Eventually, Isola did attend the drivers briefing and there was no boycott. However, many drivers come out against what Pirelli said.
"I think the short answer would be, I can't say 100% yes, and I can't say 100% no," said 4-time world champion Sebastian Vettel, whose teammate Lance Stroll suffered the crash.
Stroll was more despondent in the pre-race driver's press conference. "I don't have much to say. We drive with a tyre pressure that is legally prescribed by Pirelli. There was nothing wrong with our car. Pirelli are now going to put the pressure back on and they think that is the solution," said the young Canadian.
Verstappen kicked the rear left tyre of the car after it disintegrated cause his car to crash at over 300 kph
Max Verstappen who was the other causality and crashed while leading the race quite easily was more scathing in his assessment of the Pirelli response.
"It would also be nice to just know if it was tyre pressure-related... just speak out, I think that would be I think a bit easier to understand than I think the explanation we got so far because the team didn't do anything wrong. They explained that they don't have measurement tools during the race but we gave them our tyre pressures and they were within the limits they set," said the 23-year-old Dutchman, who almost lost the lead of the world championship due to the crash.
"If those limits are not correct, there is nothing we can do about it, we just follow what is possible within the rules. If that means we have to go up on pressures we will, everyone will go up on pressures. They have to look at themselves and we are here, of course, happy to help with everything but they already went up on pressures from Friday to Saturday so that means that something, maybe it wasn't enough," the feisty Dutchman added.
Interestingly, this issue has been picked up by the rivals of Red Bull and Aston Martin who claim this could be the reason for the performance advantage the two teams had during the race in Baku.
World champion Lewis Hamilton came out batting for Pirelli for once even though often he has been critical of the tyre manufacturer. "More often than not, [it's] that the tyres are not being run at the pressures that are being asked. We didn't have a problem with our tyres. I think they've done a great job with the tyres this year, they're more robust than before, and I think in this particular instance, I don't think Pirelli are at fault," he said.
"I'm happy that they have acknowledged that they need to clarify it, and I think what's really, really important from now is how they police it because they've not been policing how the tyres are being used, tyre pressures, tyre temperatures, and we need to do better. It's great that they've done a TD, but it's the action now. We need to see them really follow through and be really vigilant to make sure that it's equal across the field," he added talking about the technical directives Pirelli had issued in the build-up to the investigation.
Ferrari's new star revealed that modified tyre pressures would be a reason for its competitors to faster
Ferrari's Carlos Sainz Jr had even more interesting insight claiming that his team didn't have issues warming the tyres up which was reflective in the excellent progress the team had made in the last two races with pole positions for Leclerc, however, if the tyre pressures were being played around with, that would certainly give a huge advantage to its rivals.
"Baku was no exception so I'm sure every team was doing whatever it could to keep temperatures and pressures as low as possible. Whether they went below their limits only those teams can know that. But we are very good in qualifying at switching the tyres on. We are not very good in the race with overheating," he said.
"So this gives us some clues as to the reasons why we were not so good in the race, clarifications for why we can make it work over one lap in qualifying but then go backwards. There's a trend there. It's going to help us understand the whole picture," he said, which could mean the new technical directives could help Ferrari's race pace.
Even Alpine executive director Marcin Budkowki has expressed his concerns around the potential tinkering of tyre pressures.
"The reaction of the FIA really is actually not a significant change in the operating procedures, it's a lot more clarity and a lot more tightening of the operational procedures. Whether that suggests that some people were taking some freedoms with operational procedures, that's a step I won't make, because I don't know. But if that's the case, it's quite worrying, because it's a safety-critical matter," he said.
