11/05/2013
NEWS STORY
Pirelli believes that track debris was to blame for the failure which side-lined Paul di Resta on Friday afternoon, though the Italian manufacturer will review the construction of its tyres.
With almost every conversation about F1 eventually returning to tyres, Pirelli was under scrutiny again on Friday when di Resta's left-rear tyre appeared to fail exiting the final corner on to the main straight.
Echoing similar incidents that befell Felipe Massa and Lewis Hamilton in Bahrain, not to mention ongoing criticism from a number of teams, there were concerns that Pirelli's drive to produce tyres that deliberately degrade might have gone a step too far. Not so, says Paul Hembery, who insists that di Resta's failure was due to debris piercing the tread of the tyre.
"What we have changed this year is that when there is debris or an issue, it doesn't cut through the belt pack and deflate the tyre which is what would have happened last year," he told reporters. "Instead, it's arriving at the belt pack and then you get the tread being the weak point. It overheats and comes away, which visually is very dramatic, though the structure is still intact.
"Last year that would have collapsed on to the rim and the car probably would have crawled down the pitlane on three wheels," he added. "It's the mode of failure that's changed. Bizarrely, it's probably safer this way.
"For us, it's worse because it's visually, from a tyre maker's point of view, not great," he admitted. "From a safety point of view, it's probably safer because the actual tyre is still inflated. It's not something due to quality or design."
Admitting that his company will seek a solution to the problem, he warned that this might not happen until the British Grand Prix as the teams would have to approve any changes which might influence the performance of their cars.
"We can't test and if we make too dramatic changes we influence maybe the aerodynamics and some of the chassis design," he said. "If we make anything significant, we have to convey it to the teams and we have to know if that is going to affect what they are doing. It's a very delicate balance.
"Is our solution to make the tyre deflate when it has debris? Does that look better from a tyre maker's point of view? Is it worse for the teams or better? It's a strange dilemma to be in," he sighed.
Referring to the problems in Bahrain, Hembery claims that Hamilton's failure was probably due to a suspension issue or an object on track that damaged the suspension, while Massa's failures were due to debris.
"There were cuts in the tyres," he said. "I found a bit of one car in one tyre and I know which one it was because it had the branding on it. We are frustrated, because we don't like to see the tread coming off, but we are not alarmed for any safety issues."