Pirelli deny blaming teams after announcing immediate changes to their rear tyres
Tyre supplier to act immediately following Silverstone failures; Further changes to be introduced for Hungary; Practice of running tyres the wrong way round found to have contributed to British GP blowouts
By Pete Gill. Last Updated: 03/07/13 12:03pm
Pirelli have denied blaming the teams for the high-speed failures which marred the British GP after explaining why they will make immediate changes to their much-criticised tyres for this week's German GP.
After a two-day post-mortem into events at Silverstone, F1's sole tyre supplier announced late on Tuesday night that the tyres to be used in Germany will be the Kevlar-based construction tested in Friday Practice at Canada last month. A new type of tyre will then be introduced for the Hungarian GP 'combining the characteristics of the 2012 tyres with the performance of the 2013 compounds'.
Teams will also be forbidden from running their rear tyres the wrong way round after analysis of the Silverstone failures found that the practice of 'reverse mounting' was a contributing factor to the numerous blowouts.
Pirelli were later forced to deny they had sought to blame the teams for the blowouts after citing the practice and highlighting low tyre pressures in their detailed explanation of why the tyres failed.
According to the Italian firm, the dramatic blowouts which tarnished the race at Silverstone were the consequence of a perfect storm of low tyre pressures, the circuit's sharp kerbs, 'extreme' camber angles, and 'tyres that were mounted the wrong way round: in other words, the right hand tyre being placed where the left hand one should be and vice versa, on the cars that suffered failures.'
That eye-catching disclosure immediately sparked suggestions Pirelli were striving to shift the blame on to the teams and, in yet another twist to the torturous tyre saga which has dogged F1 throughout 2013, prompted a second statement from Pirelli two hours after the first in which motorsport director Paul Hembery clarified: "Contrary to the impression that some people have formed, I would like to underline the collaboration and support that we are receiving from the teams, drivers, FIA and FOM.
"In no way are we intending to create arguments or attack anybody. We have taken our responsibilities upon ourselves as our press release indicates."
Pirelli have endured widespread criticism since Sunday's race, but have insisted their tyres are safe 'when used in the correct manner'. However, amid mounting criticism of their compounds and the threat of a driver boycott, Pirelli have opted to make immediate alterations in order to strengthen the tyres and make their rubber 'easier to manage'.
"What happened at Silverstone was completely unexpected and it was the first time that anything like this has ever occurred in more than a century of Pirelli in motorsport. These incidents, which have upset us greatly, have stressed the urgency of the changes that we already suggested - which will be introduced during for free practice in Germany on Friday," said Hembery.
For the Hungarian GP at the end of this month, the new tyres will 'have a structure, construction and belt identical to that of 2012, which ensured maximum performance and safety. The compounds will be the same as those used throughout 2013, which guaranteed faster lap times and a wider working range.'
The tyres will first be run at the rearranged Young Driver Test at Silverstone following the FIA's announcement on Monday that F1 race drivers will also be allowed to run in what will now amount to a fully-fledged tyre test.
Pirelli's statement in full
'A SERIES OF DIFFERENT CAUSES LED TO THE TYRE FAILURES AT SILVERSTONE: REAR TYRES MOUNTED THE WRONG WAY ROUND, LOW TYRE PRESSURES, EXTREME CAMBERS AND HIGH KERBS
'THE 2013 TYRES DO NOT COMPROMISE SAFETY IF USED IN THE CORRECT WAY
'TO DEVELOP AND MANAGE SOPHISTICATED TYRES SUCH AS THOSE USED IN 2013, IT IS ESSENTIAL TO HAVE ACCESS TO REAL TIME TYRE OPERATING DATA. CHANGE IN THE RULES HAS BEEN REQUESTED
'ARRANGED WITH FIA WINTER TEST AND DURING THE SEASON FOR THE DEVELOPMENT OF THE TYRES
THE KEVLAR BELT REAR TYRES TESTED IN FREE PRACTICE IN CANADA WILL BE USED IN GERMANY
'FROM HUNGARY THERE WILL BE A NEW RANGE OF TYRES, WHICH COMBINES THE 2012 STRUCTURES WITH THE 2013 COMPOUNDS. THESE WILL BE TESTED AT SILVERSTONE, USING THE RACE DRIVERS AND 2013 CARS, DURING THE YOUNG DRIVER TEST
'PAUL HEMBERY: "WHAT HAPPENED AT SILVERSTONE UPSETS US. WITH THESE SOPHISTICATED TYRES IT'S VITAL FOR US TO SEE DATA SUCH AS TEMPERATURE, PRESSURES AND CAMBER. WHILE WAITING FOR A REVISION TO THE RULES, WE WILL SUPPLY TYRES THAT ARE EASIER TO MANAGE."
'Milan, July 2, 2013 - After exhaustive analysis of the tyres used at Silverstone, Pirelli has concluded that the causes of the failures were principally down to a combination of the following factors:
'1) Rear tyres that were mounted the wrong way round: in other words, the right hand tyre being placed where the left hand one should be and vice versa, on the cars that suffered failures. The tyres supplied this year have an asymmetric structure, which means that they are not designed to be interchangeable. The sidewalls are designed in such a way to deal with specific loads on the internal and external sides of the tyre. So swapping the tyres round has an effect on how they work in certain conditions. In particular, the external part is designed to cope with the very high loads that are generated while cornering at a circuit as demanding as Silverstone, with its rapid left-hand bends and some kerbs that are particularly aggressive.
'2) The use of tyre pressures that were excessively low or in any case lower than those indicated by Pirelli. Under-inflating the tyres means that the tyre is subjected to more stressful working conditions.
'3) The use of extreme camber angles.
'4) Kerbing that was particularly aggressive on fast corners, such as that on turn four at Silverstone, which was the scene of most of the failures. Consequently it was the left-rear tyres that were affected.
'The only problems that had come to light before Silverstone were to do with delamination, which was a completely different phenomenon. To stop these delaminations Pirelli found a solution by suggesting that the teams use the tyres that were tried out in Canada from Silverstone onwards. When this proposal was not accepted, Pirelli found another solution through laboratory testing, with a different bonding process to attach the tread to the carcass. So the problem of delamination has nothing at all to do with what was seen in Great Britain.
'Following the conclusions of this analysis, Pirelli would like to underline that:
1) Mounting the tyres the wrong way round is a practice that was nonetheless underestimated by everybody: above all Pirelli, which did not forbid this.
'2) In the same way, under-inflation of the tyres and extreme camber settings, over which Pirelli has no control, are choices that can be dangerous under certain circumstances. Because of this, Pirelli has asked the FIA for these parameters will be a topic of accurate and future examinations. Pirelli has also asked for compliance with these rules to be checked by a dedicated delegate.
'3) Pirelli would also like to underline that the 2013 tyre range does not compromise driver safety in any way if used in the correct manner, and that it meets all the safety standards requested by the FIA.
'The logical conclusion is that it is essential for tyres with the performance and technical sophistication of the 2013 range to be regulated and carefully controlled by Pirelli itself. In order to ensure the optimal functioning of the tyres, the Italian firm would need real-time data from the teams regarding fundamental parameters such as pressure, temperature and camber angles.
'While waiting for new regulations that would permit Pirelli access to this data, vital for the development and management of these state-of-the-art tyres, the following measures are proposed for the forthcoming grands prix, in agreement with the FIA, FOM, the teams and the drivers:
'1) The use of the evolution of the current tyre that was tested in Canada (and proved to be completely reliable) for the German Grand Prix this weekend. This represents the best match for the technical characteristics of the Nurburgring circuit. In particular, the rear tyres that will be used at the German Grand Prix, which takes place on July 7, have a Kevlar construction that replaces the current steel structure and the re-introduction of the 2012 belt, to ensure maximum stability and roadholding. Given that these tyres are asymmetric as well, it will be strictly forbidden to swap them round. The front tyres, by contrast, will remain unaltered.
2) From the Hungarian Grand Prix onwards, the introduction of a new range of tyres. The new tyres will have a symmetrical structure, designed to guarantee maximum safety even without access to tyre data - which however is essential for the optimal function of the more sophisticated 2013 tyres. The tyres that will be used for the Hungarian Grand Prix onwards will combine the characteristics of the 2012 tyres with the performance of the 2013 compounds. Essentially, the new tyres will have a structure, construction and belt identical to that of 2012, which ensured maximum performance and safety. The compounds will be the same as those used throughout 2013, which guaranteed faster lap times and a wider working range. This new specification, as agreed with the FIA, will be tested on-track together with the teams and their 2013 cars at Silverstone from 17-19 July in a session with the race drivers during the young driver test. These tests will contribute to the definitive development of the new range of tyres, giving teams the opportunity to carry out the appropriate set-up work on their cars.
'Paul Hembery, Pirelli's motorsport director, said: "What happened at Silverstone was completely unexpected and it was the first time that anything like this has ever occurred in more than a century of Pirelli in motorsport. These incidents, which have upset us greatly, have stressed the urgency of the changes that we already suggested - which will be introduced during for free practice in Germany on Friday. We would like to acknowledge the willingness of the FIA, FOM teams, and drivers to act quickly to find an immediate solution to the problem. In particular, the adoption of winter tests, arranged with the FIA, that are more suitable for tyre development and the possibility of carrying out in-season testing will contribute to the realisation of tyres with increasingly improved standards of safety and performance. I'd like to re-emphasise the fact that the 2013 range of tyres, used in the correct way, is completely safe. What happened at Silverstone though has led us to ask for full access to real time tyre data to ensure the correct usage and development of tyres that have the sophistication we were asked to provide and extremely high performance that has lowered lap times by more than two seconds on average. While we wait for a change in the rules, we will introduce tyres that are easier to manage."'