Bridgestone clarifies Turkey failure cause

Early reports had pointed to a phenomenon known as 'chunking' as having been the culprit, and while the Japanese tyre company has ascertained that this was indeed the case, there was confusion in some initial reports as to what exactly the term 'chunking' meant.

Initial descriptions suggested that the situation arose when marbles from the track became attached to the tyre surface, creating a larger build-up of material that eventually led to weaknesses in the casing.

However Kees van de Grint, Bridgestone's head of track engineering operations, told autosport.com that the reality was actually the complete opposite - pieces leaving the tyre surface, rather than attaching themselves.

"Chunking is when pieces of tyre leave the tread, usually due to either mechanical reasons or because of heat," van de Grint explained.

"There could be an internal blister, the rubber melts and then the holes which are created are called chunking. When pieces of the tread leave the tyre, we call the holes that are left 'chunking'."

Van de Grint said that while chunking is a normal phenomenon that is typical of certain circuits, much in the same way as blistering and graining, Hamilton's problem in Turkey was exacerbated by additional circumstances, started with the massive loads that were being generated through Turn 8.

"The failure in Turkey was caused by stress; it was nothing to do with the heat," he said.

"The appearance of the chunk is different, and a good eye can see the difference. You can analyse from the appearance whether it was caused by heat, or caused by stress. It can even be caused by damage.

"It didn't only happen to Lewis; it happened on more cars. But on Lewis's car, because of the tread breaking up, as a result of stress in this case, the belt area was not protected anymore.

"And then another force was applied from outside - maybe it was kerbs, maybe it was braking - and it was applied on the unprotected belt. Then the belt material broke, and that caused the belt to become separated and go flying away.

"Of course Lewis was quite quick in Turn 8, and with more fuel than anybody else. It could have been a kerb that he hit, it could have been just braking, but there was an additional force that forced the belt to break. And that was it.

"Some survive, but unfortunately Lewis didn't because of some other force that was applied in his case."