Pirelli reveal results of investigation into Baku tyre failures

Formula 1’s tyre supplier Pirelli say an investigation into the left-rear tyre failures suffered by both Lance Stroll and Max Verstappen in the Azerbaijan Grand Prix demonstrated there was “no production or quality defect” on any of the tyres “nor was there any sign of fatigue or delamination”.

Aston Martin’s Stroll suffered a blowout near the pit entry and spun hard into the wall, bringing out a Safety Car. Red Bull’s Verstappen then suffered a similar blowout going down the main straight, when he was leading the race, and speared into the wall. Both drivers emerged unscathed.

Initially, Pirelli believed debris was to blame for the two incidents, but on Tuesday evening, the Italian manufacturer released the results of their analysis which showed that this was not the case.

On the eve of the French Grand Prix, Pirelli said in a statement: “This analysis also took in the tyres used by other cars in the race, which had the same or a higher number of laps on them compared to the ones that were damaged. The process established that there was no production or quality defect on any of the tyres; nor was there any sign of fatigue or delamination.

“The causes of the two left-rear tyre failures on the Aston Martin and Red Bull cars have been clearly identified. In each case, this was down to a circumferential break on the inner sidewall, which can be related to the running conditions of the tyre, in spite of the prescribed starting parameters (minimum pressure and maximum blanket temperature) having been followed.”

Following the investigation, Pirelli submitted their report to all 10 teams as well as governing body the FIA and issued a new set of protocols which will come into force at this weekend’s race in France.

“The FIA and Pirelli have agreed a new set of the protocols, including an upgraded technical directive already distributed, for monitoring operating conditions during a race weekend and they will consider any other appropriate actions,” added Pirelli.

Shortly after the tyre supplier revealed the results, Red Bull issued a statement: “We have worked closely with Pirelli and the FIA during their investigation into Max’s tyre failure on lap 47 of the Azerbaijan Grand Prix and can confirm that no car fault was found.

“We adhered to Pirelli’s tyre parameters at all times and will continue to follow their guidance.

“We are grateful that following the weekend’s high speed impacts no drivers were injured.”

Aston Martin later issued their own statement: "Following the tyre issue on Lance Stroll’s car on lap 29 of the Azerbaijan Grand Prix, we have worked with the FIA and Pirelli during their investigation.

"We can confirm there was no car fault that caused the tyre to fail.

"The team has always operated its tyres within the Pirelli prescribed parameters and will continue to do so."