US Grand Prix Technical Preview - Q+A
with Pascal Vasselon
13.06.2007
Can you talk through Jarno's suspension problem in Friday practice in Canada?
The problem, which was visible, was that we broke the front right upright around the connection of the lower wishbone. The first thing that guided our analysis was that this upright design is almost two years old, introduced with our major kinematic suspension change with the TF105B at the end of 2005. That told us it was not a basic design problem and we had to look for differences compared to other years because we have already raced in Montreal with this design. We came to the conclusion that the combination of set-up parameters we used to work around the huge rear limitation, which all cars have, was generating interference between the lower wishbone fixation and the upright. We had to find some counter-measures and we implemented two. The first was technical, going back to a range of set-up parameters in terms of camber, ride height and suspension travel, that cleared the interference. Secondly, because we didn't want to take any further risks, we asked the drivers to avoid the extreme part of the kerb in Turn 8. I would say it was a unique loading case related to the highest part of that kerb.
Was Jarno taking more kerb at Turn 8 than Ralf?
Yes, and it wasn't just a case of taking more kerb, it was also a question of Jarno using a different driving line on the kerb.
How much lap time did it cost Jarno to no longer use that kerb?
From our performance analysis of each sector it looked like around two tenths of a second.
Given the circumstances, how good a job did Jarno do to qualify 10th?
He did a great job but even taking into account those two tenths, it was the first time that we did not have the potential to be ahead of the tight midfield group comprising Red Bull, Renault and Williams.
What caused Ralf to qualify 18th?
Ralf's weekend had actually been going pretty well. He'd been on the pace from the very early laps of first practice but was unfortunate that in qualifying he encountered four cars on his fast lap. That lap was obviously going to decide whether he went into Q2, he had to let Wurz pass, and met Barrichello, Button and Kubica.
Presumably the red flag made the session even more hectic?
Exactly. It meant a high density of traffic at the end of the session.
Were you surprised to emerge from the race with a point?
It was one of those chaotic races where just about anything could happen, and did! I have to say, first of all, that I am delighted that Robert Kubica has escaped from such a horrific looking accident relatively unscathed. He had been racing with Jarno and I know that Jarno was concerned about the situation because he had seen the medical car out for a long time. After that, Jarno had a flat tyre and had to pit, then had a late stop to make, after which he went straight on into the tyres at Turn 1. It's perhaps understandable that his thoughts were elsewhere and the whole team wishes Robert well. Ralf was fuelled up for a long first stint which meant he stayed stuck in traffic at the beginning of the race but he has been reasonably competitive when in free air and was rewarded with a point.
Moving on to Indianapolis, how big a set-up compromise is it?
It has been said that Indy is two circuits in one - an oval with a Monaco-style infield, two very large compromises from the aerodynamic side. Typically when you scan the simulation for your different possible wing levels, you get a very flat answer. That means that in terms of lap time you can achieve very similar performance with high or low downforce. So Indy is a place where theoretically you could go with a very different downforce level. For the race you have to add another parameter, which is the capacity to pass or avoid being passed, because there are definitely overtaking opportunities. You have the banking on to the long main straight with a very real overtaking possibility at the end of it.
So that means you might qualify with higher downforce than you race?
You will use the limits of the adjustments you are allowed to make between qualifying and race but, overall, Indy is always the first track when you start to use your low downforce level settings. Montreal is medium/low downforce and Indianapolis is definitely low downforce.
What about other concerns?
There should be nothing too significant. There are no braking issues simply because there is so much time to cool down the brakes around the banking and down the straight -- something like 23 seconds at full throttle.
Are tyre concerns a thing of the past?
Yes. We are now using different constructions and you could almost say that nobody is even thinking about it anymore.
Do you get a feel for the size of Indianapolis and its history?
Truthfully, not really. I know that there is a huge racing heritage there, of course, and the Indy Museum and everything, but part of the problem is that the race follows straight on from Montreal. Back-to-back flyaway races are quite demanding for team personnel and we are really too preoccupied to enjoy our surroundings!