An overview of the tire failures of 2013

In the last few days there has been a lot of discussion about the cause of the tire failures that F1 experienced at Silverstone. Following this discussion I thought it would be interesting to look at some of the earlier tire failures and what Pirelli said about those failures. I have tried to sum up events as best I could and provide relevant sources, but feel free correct me if you see some wrong or add additional information if you feel I have missed something.

This post is rather long, but I sum up things towards the end so you can just jump to that if don’t feel like reading the whole thing.

- April 20th – Bahrain GP –

A Mercedes driven by Lewis Hamilton suffers a left rear tire delamination during FP3 while using the medium compound tire. Pirelli states that cut were found on the rear tire of Geido van der Garde and that they suspected a single piece of debris caused cuts in both his and Hamiltons tires. Paul Hembery stated “Van der Garde was following and his rear tire had a 10cm cut through it, a very aggressive cut that could only have come from a bit of metal”. Pirelli walked the track following the day’s activity, but were unable to locate and identify the specific piece of debris.

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Pirelli later expressed doubt as to their initial conclusion concerning Hamiltons tire.

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- April 21st – Bahrain GP –

A Ferrari driven by Fellipe Massa suffered two right rear tire failures during the race. The first was a partial delamination on the hard compound tire, the second was a puncture which may have been delamination related, also on the hard compound tire. Pirelli determined that both failures were due to cuts in the tire. Paul Hembery said “The first one we have got a big cut through the tread pack and the second one has a cut in the sidewall. We can see through the tread as there is a hole through the top of the tread as well”. Pirelli concluded that both of these cuts were caused debris, Massa himself stated “Maybe there was debris on the track, but I didn’t feel any contact”. Following the race, Pirelli recovered a large amount of debris from the track, but were a least initially unable to match any of it to the damage on Massa’s tires. Pirelli took the debris back to the lap to continue the investigation, but I have been unable to find any sources on whether they made any progress with that investigation.

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- May 10th - Spanish GP –

A Force India driven by Paul Di Resta suffers a left rear tire delamination during FP2. The tire was of the medium compound.

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The next day, Pirelli concluded that the delamination was caused by a “cut in the rubber”. At the time Pirelli speculated that debris could have caused the cut, but they were unable to identify the piece of debris and from whose car it should have originated.

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- June 29th - British GP –

A Mclaren driven by Sergio Perez suffered a left rear tire blowout during FP3, while using the hard compound tire. Pirelli stated that the explosion was caused by a cut in the tire. Paul Hembery said “First findings show that this was unequivocally caused by a cut in the inner sidewall: something went into the tyre, pierced it, and then came out again, in the direction of travel.” “Whether that was a piece of debris or the edge of a kerb is hard to say at the moment and it is important to point out that this incident was unrelated to any of the delamination issues we have had in the past.”

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- June 30th – British GP-

Three cars, a Mercedes driven by Lewis Hamilton, a Ferrari driven by Felipe Massa and a Toro Rosso driven by Jean Eric Vergne, suffered rear left tire blowouts in quick succession, in the early part of the race. Hamilton and Massa were using the medium compound tire, while Vergne was using the hard compound tire. After the first pitstop, the rear left tire removed from the Red Bull driven by Sebastian Vettel was reported to have suffered at least one very deep cut in the surface of the tire. Towards the end of the race the Mclaren driven by Sergio Perez also suffered a rear left tire blowout, while he was using the medium compound tire. The Sauber driven by Esteban Gutierez is reported to have suffered a front tire failure, and the Ferrari driven by Fernando Alonso is reported to have suffered a rear tire deflation, but it is unclear to what degree these issues were related to the blowouts.

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So to sum up.

During three races this season, Bahrain GP, Spanish GP, and British GP, deep and severe cuts in the tires have been reported. These three tracks are all well known to be hard on tires and the races happened in relatively hot conditions. No problems with similar cuts have been reported during any of the other races.

Initially these cuts were attributed to pieces of debris on the racetrack by Pirelli, and they even suggested that the “aggressive cuts” had been caused by metal debris, rather than the more common carbon fibre debris. Pirelli has been unsuccessful in linking these cuts to specific pieces of debris, and have not found any metal debris.

Follow the tire blowout that Perez suffered during FP3 at Silverstone, Pirelli for the first time mentioned that one of these cuts could potentially be attributed to “the edge of a kerb”. Following the race at Silverstone, most cuts to tires during the race were attributed to Kerbs.

Driving style seems to have impact on who suffers tire failures, as several drivers have suffered multiple failures when others have suffered none. Massa: 3 failures, Hamilton: 2 failures, Perez: 2 failures, Di Resta: 1 failure, Vergne: 1 failure.

All failures so far have been on the Medium and Hard compounds, no problems have been reported on the Soft and Supersoft. There could be a number of reasons for this, but the main seems to be that the softer tires are less used and have been used in less extreme conditions. Of the nine major failures five were on the Medium compound and four were on the Hard compound.

This is the facts, feel free to draw whatever conclusions you want from them.