British GP tyre failures: What could have been the reason?

Detail view of Pirelli tyres following the British Formula One Grand Prix at Silverstone

But what actually happens when the tyres hit such a damaged kerb? Oscillations are induced into them after running over the kerbs. To be more precise standing waves are generated which can sometimes produce stresses beyond which the design permits. Infact, these standing waves were the reason behind Michelin runners suffering heavily on the long banked curve at Indianapolis back in 2005 and boycotting the race purely for safety reasons- a separate case altogether but having some similarities.

Another interesting point is that Kevlar has much better damping properties than steel, so if a Kevlar belt would have been present the oscillations would not have reached alarming proportions. Remember we didn’t see any such problems in Silverstone last year when the situation was quite similar with a wet Friday and a sunny Sunday. Why this weather pattern needs to be discussed? Because the teams didn’t have enough dry long running data either last year or this year, so lack of data can be ruled out as a potential cause.

Minimum pressure specifications

Pirelli always specify a minimum pressure that must be maintained inside the tyres (generally 18 psi) for higher longevity and prevent damage from the kerbs. But teams rarely obey that and to gain more performance reduce the pressures so as to increase the contact patch and hence the grip. On these lines, it is important to note that neither Lotus nor Force India experienced any problems with the tyres during the race. They later announced that they had stuck to Pirelli’s specification while some of their rivals had to later increase the pressures by 2 psi to prevent their tyres from failing.

The failure on Perez’s car during the dying laps puts a question mark on that. The other three had occurred during the first third of the race and most teams had taken the precautionary measure of increasing the pressures immediately after that. So did McLaren not change their pressures? Or did the failure occur even after that?

This and many other questions remain unanswered. With Pirelli summoned to the Sporting Working Group meeting this week, the haze might clear a little. But the threat of a boycott for the next race looms large and with just 4 days to free practice on Friday there is very less Pirelli can do to stop it. Will we see another USA 2005? At least fans wouldn’t feel cheated this time around, seeing that the drivers’ lives are being put in danger.