Pirelli reveals early findings from Baku F1 tyre blowouts

Stroll and Verstappen’s races ended prematurely in Baku after two separate tyre failures, resulting in high-speed crashes.

Both drivers were running on Pirelli’s C3 hard tyre and after the race, Isola revealed Pirelli found cuts on Lewis Hamilton’s left-rear tyre.

“Obviously we didn’t have the time to perform a full investigation and we need to send the tyres back to Milan,” Isola said. “The plan is to send them by air freight to Milan tomorrow and make an investigation in our laboratories, on this set, plus some other sets used in the same stint. 

“Looking at the tyres used in the second stint, for most of the drivers we didn’t find any evidence, or anything. I believe I can exclude that failures were due to tyre wear, because it is not a matter of tyre wear.

“We found a cut on the inside shoulder of a tyre of rear left tyre used by Hamilton in the same stint, the cut was quite deep and big, and probably 6-7 cm, but not cutting the construction, so the tyre was still in one piece, just the tread is cut, and when there was the red flag and Lewis came to the pit lane and changed the tyres we were able to find the cut.”

While Pirelli doesn’t want to give a conclusive answer until it has carried out a full investigation, its initial verdict is that debris could be the likely cause of the tyre failures in Baku because of what it found with Hamilton's tyres.

“There was no sign, or any warning, according to the teams,” Isola added. “We have to receive the telemetry from them, but they told me there was no warning, no vibration, nothing to think there could be something in the tyres.

“These are the main element collected in this short period of time. Consider that the tyres fitted on the cars that crashed were back in the garage and in our fitting area just minutes ago, so we need a bit of time to analyse them. I don’t want to give any preliminary conclusion.

“It seems it is a cut due to debris. It is not more stressed tyre, we have evidence of another cut in the same position. Both the accidents happened on more or less the same part of the circuit and a few laps difference we have other cars with the same number of laps, same tyres, without any issues.”