Formula One’s governing body took emergency action ahead of a potentially title-deciding Qatar Grand Prix sprint race on Saturday after Pirelli warned of the risk of sudden tyre blowouts.
The governing FIA introduced an extra practice session ahead of qualifying for the 100km sprint and said Sunday’s main event could become a mandatory three-stop race to limit tyre usage.
The FIA also made revisions to the track limits at turns 12 and 13.
The qualifying shootout was delayed by 20 minutes to accommodate the extra track time.
Red Bull’s Max Verstappen is poised to win his third championship in the sprint, the Red Bull driver needing only three points to put the title out of reach of team mate Sergio Perez.
Verstappen has already qualified on pole for Sunday’s grand prix.
Further tyre analysis will be carried out after the sprint to decide if further action is needed before Sunday’s main event.
Should that be the case, teams will be told not to exceed 20 laps on new tyres used in the race.
Pirelli’s analysis of returned tyres used in Friday’s sole practice session found a small separation in the sidewall between the topping compound and the carcass cords on many of those used for around 20 laps.
“It is the view of the FIA and Pirelli that a significant number of additional laps on these tyres could result in circumferential damage of the tyres with subsequent air loss,” added the governing body.
“Tyres analysed with lower lap numbers showed a much-reduced extent of the issue.”
The FIA said the issue had likely been caused by the sidewall coming into contact with the 50mm “pyramid” kerbs used at the circuit, with drivers riding the kerbs to get the quickest lap time.
Haas team boss Guenther Steiner said the situation was embarrassing for the sport.
“This should not happen in Formula One,” the Italian told reporters.
The Qatar circuit has been resurfaced since it last hosted a race in 2021, its debut on the calendar.
That race saw a spate of tyre failures which Pirelli said then were caused by running over the kerbs.
Pirelli motorsport head Mario Isola told reporters on Saturday that the damage was microscopic, similar across all compounds and had been reported to the FIA on Friday.
“It’s not just the geometry of the kerbs, because these kerbs are used in many other circuits, it is the time and the speed they (the drivers) stay on the kerbs that is important,” he said.
“During the lap all the drivers are spending quite a lot of time at high speeds on the kerbs and this is damaging the construction.”