Paul di Resta's close shave: Pirelli probe tyre flops in accident fear

Italian tyre suppliers Pirelli have launched an investigation following a spectacular failure that affected Force India driver Paul di Resta on Friday.

The Scot was forced to bring his Force India car to a halt after the tread completely came off the left rear tyre during the second free practice session ahead of Sunday's Spanish Grand Prix.

An initial analysis suggested that the problem was caused by overheating of the tread rather than debris on the circuit.

Pirelli motorsport director Paul Hembery said: "It doesn't look pretty when you get the tread coming away like that. If anything like that happens, it tends to collapse the tyre on to the rim, so it did not look good. This year we are seeing the tread coming away.

"Visually it looks rubbish. We don't like that and we are looking at seeing if there are things we can do to eliminate that."

Di Resta's frightening experience was not the first of its type this season.

Lewis Hamilton suffered a similar incident during practice with Mercedes at the Bahrain Grand Prix.

Hembery said that he believed a new system of construction of the tyres this year -- with the sidewalls made much stiffer -- had contributed to this particular type of failing.

"That has pushed the failure into a different type of conclusion, so we are looking at what we can do under the constraints that we have," he explained. "We dont like it and we are taking a very close look at it."

Di Resta's failure came soon after Hamilton's experience and Brazilain Felipe Massa's double punctures, also in Bahrain.

Di Resta said that he was not unduly concerned about the tyre failure -- which he said had been unexpected.

"It is not something we have experienced before, and we as a team are quite light on tyres," he said.

"I don't' think it is anything we do with the tyres. Whether it is something to do with the compound I don't know."

Other drivers have raised more concerns.

Sergio Perez of McLaren said: "With the tyre how it is at the moment, you do a couple of laps and then it is very difficult to have any feeling. It is a big concern for all of us.

"With two, three cars per weekend (hitting trouble), it can really be a serious accident."

Pirelli have been under pressure to improve the reliability and durability of their tyres for two seasons because their low-wear thresholds have created too much uncertainty in Formula One and turned the sport into a tyre-wear contest.