Pirelli’s motorsport director Paul Hembery has admitted that the Italian tire supplier underestimated the effect of allowing teams to undertake ‘tire swapping’ at the last race, believing that this was the biggest factor in causing the multiple failures at the British Grand Prix.
Lewis Hamilton, Felipe Massa, Jean-Eric Vergne, Sergio Perez and Esteban Gutierrez all suffered from blowouts during the race at Silverstone, triggering Pirelli to make changes for this weekend’s race. Hembery has admitted that it was a mistake by Pirelli which caused the madness to ensue.
“Just to recap, at Silverstone we’d underestimated the impact of swapping the tires,” Hembery said in the Friday press conference. “The cars were two, maybe three seconds quicker this year. Whilst we’d allowed the teams to do that, we’d underestimated the impact on the tire.”
Teams have been permitted to switch which side of the car they run the Pirelli tires on – i.e. using the front-left tire on the front-right of the car – and it has aided tire management, reducing wear in places. However, Hembery explained how this has caused a weakness in the tire which was evident at Silverstone.
“When you swap them around that creates a point with the metallic belt that we have on it, on the left hand side, the camber side, and that created the weakness.We got that wrong and we needed to get it right going forward.”
As a result, Pirelli have changed the structure of the tire, using a kevlar belt in the tire before reverting to the 2012 constructions for the Hungarian Grand Prix at the end of this month. The process of tire swapping has been banned for this weekend by the FIA following guidance from Pirelli.