US GP: Michelin preview

After bidding farewell to Europe, Michelin and its partner teams are gearing up to return to North America for the penultimate Formula One event of the season, which takes place in Indianapolis.

The Clermont-Ferrand firm's motorsport director Pierre Dupasquier says: "The previous race in Monza had many positive elements for us, in fact I'd go so far as to say it was extremely positive. Our partners monopolised the top of the timesheets from free practice on Friday morning until the Sunday warm-up, Juan Pablo Montoya made history by setting the fastest-ever pole position lap in his Williams-BMW and our tyres enabled Jaguar Racing and Renault F1 to take third, fourth and fifth places.

"Our compounds did everything that was required of them: they proved to be fast, durable, consistent and sufficiently resistant to the hot temperatures that we didn't suffer any blistering. We have every reason to believe our development programme is heading in the right direction."

Atlantic crossing ...

The track at Indianapolis is unlike any other on the F1 calendar. It measures 4.192 kilometres (2.605 miles) and requires teams to find a set-up that allows their chassis to be quick around the ultra-fast banking without over-compromising performance through the tight and twisty infield.

Michelin's F1 project chief Pascal Vasselon explains some of the challenges the track presents:

"Indianapolis is a circuit of contrasts, a bit like the old Hockenheim: there are some high-speed sections that demand very little wing, but you need as much downforce as possible for the tighter parts of the track. You have to find the best possible aerodynamic compromise, something that offers enough downforce to optimise tyre grip without leaving you prone to being eaten up down the long straight that runs from Turn One of the famous oval.

"Custom dictates that Indy is a one-stop race because a heavy fuel load is not too punitive in terms of lap times. You lose about 0.25 seconds for every extra 10kg you carry.

"As far as tyres are concerned, the high-speed banking generates a considerable amount of heat, particularly on the left-hand side of the car. On this section of the track vertical loads increase and the effect of centrifugal force is partially offset. You also have to take into account an increased degree of tyre scrub.

"The track surface is quite abrasive on the banking but fairly normal elsewhere. Our two dry-weather compounds have been selected from the middle segment of our range and were designed to cope first and foremost with the most challenging part of the track, the aforementioned banking."

-michelin-