Indy Hindsight: Q&A with Nick Shorrock

Q: Can you now throw more light on why the Michelin tyres failed at Indianapolis?

Nick Shorrock: If you go back through the series of events in Indy, on Friday afternoon we had two failures, first of all [Ricard] Zonta and then Ralf [Schumacher], and then when we demounted all the tyres on Friday afternoon there were another six tyres that had the anomaly. All the work that we were doing at the track visually inspecting the tyres and then back in Clermont.

Obviously the first thing we tried to do was to recreate the problem we were seeing. That was fairly easy to do because we had tyres from the same production batch back in Clermont and we used the same verification techniques that we use on all our tyres.

Q: And what are those techniques? You use a high-speed rig?

Shorrock: Yes, basically. It spins the tyre at a certain speed and we know when we reach a certain level and a certain time. That correlates after we do all the tests that we do on the circuit and, in fact, no tyre gets out of the four walls of Michelin unless it's passed a certain number of validations. So we ran all that on Friday evening and by the time we got the information back on Saturday morning, the problem was that we couldn't say what the problem was, and that was the most worrying thing.

Our first indication was that we probably had lower pressures than were perhaps necessary, so we gave some recommendations to the teams, as we explained on Saturday morning, and made specific indications to the teams to increase the pressures and in some instances some of the mechanical set-ups of the cars - camber settings. And also that they should use new sets of tyres and run no more than 10 laps.

Q: Why the 10 laps?

Shorrock: That was because we knew that the teams were going to go out and do a certain amount of flying laps but they were also going to have a certain number of 'in' and 'out' laps, so it was a compromise between doing nothing and getting the teams running. That went off very well and we were able to do the Saturday morning tests and the qualifying.

We then took the tyres again from Saturday morning and started to detect tyres that hadn't even done 10 laps, having a problem. That's why we need to be very clear that this 10 lap thing just got totally stopped. There was no way we were going to run that. Because some of the tyres we saw had anomalies on them after as few as three laps.

That then set us in motion again, back in Clermont and in Greenville, South Carolina, and also later on Saturday afternoon and evening, in Akron, to try to understand the problem. And none of those tests brought about a satisfactory conclusion. It helped us understand a lot more about it - such as where the critical areas were - and that's why on Saturday night we made the statement that we made and the request that we made to the FIA, that if we were able to limit the speed going around Turn 13, then we would envisage racing.

What we've done since is to go further into the analysis of the tyres and I think the first thing to stress is that the manufacturing detail, whether it be the raw materials we had for the tyres or the manufacturing process - at no time were found to have any anomalies. So that led us onto the next item, which was looking at the combined effects of running on the circuit. We identified three points: the speed, the lateral acceleration, and the dynamic loads.

Q: When you take those three elements, weren't they, broadly speaking, the same as had been seen before at Indy?

Shorrock: No. If you go back to last year, the difference between last year and this year is that we've changed the type of tyre. The casing itself has fundamentally changed.

Q: Is it fair to say it's softer?

Shorrock: I wouldn't say it's softer or harder. It's changed because instead of doing 80-90kms on a set of tyres, you've got to do closer to 500kms. The next thing is that all the teams, because of the rule changes, have also worked on their aerodynamics, their chassis and their engines and one of the things we do on a regular basis when we're out testing is knowing that there are different packages and evolutions, we try to [run] up to date with all those and are always validating how our product is evolving. Our process for defining the tyre for Indy was to use a certain amount of information that we had from our teams testing in Europe and then, subsequently, simulation.

Q: Now, some people believe that the problem with Turn 13 is that you get more vertical load than anywhere else and that is very difficult to simulate. Is that true?

Shorrock: Well, certainly, one of the things that we weren't able to do is to take the conditions of Turn 13 at Indianapolis - and you know better than I that you can take turns elsewhere on other circuits and they are all different, not only because the circuit is different but because the cars are running different packages and so forth. But in this particular instance we have not been able to test in the particularly severe conditions on a banking which is unique in the 19 races that we are going to do in 2005.

Q: If there is more vertical load on a tyre in Turn 13...

Shorrock: But it's not just vertical load, it's a combination. You've also got lateral acceleration and so on. What we've been able to clearly identify is that it's a combination of those three elements that have taken us outside the specification that we thought we needed.

Q: I've heard a suggestion that one of the things you may have had to do, because you couldn't simulate Turn 13 accurately, was to reduce the pressure instead to get some sort of approximation when you were doing the simulation. Is that correct?

Shorrock: We're not getting into that. Again, when we arrive at a track you have a tyre casing and on that you are going to put a lump of rubber in order to produce the prime and the option tyre. For any circuit we use previous experience and we also define a number of pressure settings for racing. And that's exactly what we did. We didn't go and specifically reduce pressure.

Q: Some engineers have suggested that it is not just Turn 13 at Indy, and that you go to places like Turn 3 at Barcelona or even Copse at Silverstone, where you have actually got greater loadings. So if the problem is not principally the vertical loads, then you could also face problems elsewhere?

Shorrock: One of the difficulties is that everyone has got their own version. What we tried to do was analyse specifically the combination of those three factors. Sure, you can go to a track like Barcelona, where you are going to get much higher speed but perhaps the lateral acceleration or the downloads are not going to be as demanding.

Q: So you are confident that you won't face that combination anywhere else?

Shorrock: I think it's very clear. All the work we have done has been able to demonstrate that this particular turn, on that particular circuit, this year, 2005, was the problem. Again, there's all this emotion of 'but you've been there for five years.' But that really is irrelevant. What's important is that in 2005 the conditions we found were far more severe than anywhere else and the simulations we've been able to run have justified the choices of tyres that we have made so far this year and that we are intending to make in the weeks and months ahead.

Q: If we continue to have two tyres in F1, have you had sensible discussions about ways of limiting testing?

Shorrock: First of all we are working hard inside to be able to do more work validating before we get to the track so that we can actually perhaps limit the number of choices that we eventually run on the track. And the teams are of the same mentality. They are pushing us very hard to see what we can do not to have to do so much testing. And we can do that.

Q: But there's no way that you could actually define a spec tyre when you have more than one company.

Shorrock: No, but the spirit of the competition doesn't ask for that. That's my view anyway. I don't think that's what we want. These guys are chasing hundredths through modifications in their wind tunnels which are working 24 hours a day, seven days a week, and they'll continue to do that. The tyres are just another element.

Q: FIA president Max Mosley said, last year, that that the governing body should give a year's notice if a tyre company is not going to be allowed to continue (for instance via a single-tyre rule). Have you been given any notice?

Shorrock: None whatsoever.

Q: So as far as you're concerned you are racing next year?

Shorrock: We're racing. We're there, we've got partners expecting us to be there and we've got a programme that's being prepared for 2006.

Q: If it does go single tyre, would you tender for it or would you not be interested?

Shorrock: I think we'd take a long period of time just to think about it. The spirit of Michelin is that we are in competition and it's really for that. It's that which make us progress. Right now, we would say we don't see the sense of a single supplier and just supplying a single tyre. And certainly, we wouldn't want to get into ... because when you talk about tender, is it the highest tender or the lowest...

Q: In the correspondence being batted back and forth between Max Mosley and Edouard Michelin, Edouard referred to Max making contentions that were erroneous based on mere allegations. Could there be some legal repercussions?

Shorrock: I don't know what he's going to come up with. We have no legal contact or link with the FIA.

Q: No, I actually mean from your side?

Shorrock: I think at the moment we are just disappointed at a certain number of things that have been said and we probably want to understand completely where that information comes from. And then discuss it with him, if the FIA believes it to be true. At the moment, that's where we are. We'll see what comes of that.