Pirelli explains long stints cause of F1 British GP tyre failures

Both Mercedes drivers and McLaren's Carlos Sainz Jr sustained front-left tyre punctures during the final laps of last weekend's British GP, with Lewis Hamilton winning the race on three wheels after his tyre failed with half a lap to go, as both Bottas and Sainz dropped out of the points after their late stops.

Pirelli Formula 1 boss Mario Isola suggested after the race on Sunday the unexpectedly long second stints could be a key factor to the late failures, while the "biggest forces ever seen on tyres" in F1 was also a contributing factor.

PLUS: Why Silverstone is "not friends" with tyres

Every driver except Romain Grosjean and Alex Albon pitted on lap 12 or 13 during the second safety car period, triggered by Daniil Kvyat's crash that co-incidentally was because of a right-rear puncture, to reach the finish of the 52-lap race on the hard tyres.

"The key reason is down to a set of individual race circumstances that led to an extremely long use of the second set of tyres," the Pirelli report confirmed.

"The second safety car period prompted nearly all the teams to anticipate their planned pit stop and so carry out a particularly long final stint: around 40 laps, which is more than three-quarters the total race length on one of the most demanding tracks of the calendar.

"Combined with the notably increased pace of the 2020 Formula 1 cars (pole position was 1.2 seconds faster compared to 2019) this made the final laps of the British Grand Prix especially tough, as a consequence of the biggest forces ever seen on tyres generated by the fastest Formula 1 cars in history.

"The overall result was the most challenging operating conditions for tyres. These led to the front-left tyre (which is well-known for working hardest at Silverstone) being placed under maximum stress after a very high number of laps, with the resulting high wear meaning that it was less protected from the extreme forces in play."

Pirelli will stick with its original plan to go one step softer for this weekend's 70th Anniversary GP at Silverstone, with the C2, C3 and C4 in use, without the hardest C1 compound.

However, it is likely to mandate higher minimum pressures as a safety precaution.

There was no mention of debris as a contributing factor, despite speculation that Kimi Raikkonen's late front wing failure could have played a role.