Britain Preview Quotes: Renault

Jarno Trulli: "The R24 was very competitive with Ferrari last weekend in Magny-Cours, and we hope to be able to continue that in Silverstone. Personally, I will obviously be looking to get over my disappointment from France. Looking back at the last lap, I was quite wide on the entry to the penultimate corner, which gave Rubens the opportunity to make his manoeuvre. Once he had done that, though, I had two options: either I could try and close the door and risk a collision and not finishing, or I could accept I had made a mistake. I was really dejected after the race, but that's reality in Formula One: you cannot afford even the tiniest mistake. It was a hard lesson to learn, but I am determined to come back stronger this weekend in Silverstone. I was on the front row there last year - after our performance in Magny-Cours, we have to be looking for podium finishes once again.

"Silverstone is another technical circuit, and very demanding for the cars: it has every type of corner, so it is not easy to find the right set-up and set a good lap. When we are working in practice, we need to make the car responsive through the fast and slow corners, and find the confidence to push right to the limit: there are a number of corners where you need to be very committed to get a quick lap-time, like Copse or Bridge. In terms of enjoyment, Becketts is definitely the best section of the circuit, but every part is challenging."

Fernando Alonso: "I'm feeling great coming in to the Silverstone race. Magny-Cours was a strong race for the whole team, and we really forced Ferrari into racing hard for the win - not many people have done that this year, so really we should be pleased. I think Silverstone should suit us quite well too: you need good aerodynamic performance there, and we have that. It is a power circuit, and we were a little bit behind our rivals at the last test in June, but we have found more performance since then. I am expecting us to be very competitive.

"In terms of driving the circuit, Silverstone is one of those places where it is hard to make a real difference: every driver knows it, and we test there a lot, so the performance between the drivers is quite equal - there is not much advantage to gain from circuit knowledge. The first sector is undoubtedly the best - with high speed corners, it is interesting for the driver. But the third sector, which looks quite normal, quite standard, is where you can gain a lot of time if you really focus on it. The other strange thing at Silverstone is the wind direction - as a driver, it is very hard to tell what is happening. You can guess, but never be totally sure. Usually, we only find out about a tailwind or headwind when we start braking, and find it is too late or too early - so you sometimes need to be able to adjust very quickly!"

Bob Bell, Technical Director

Q. Bob, what was your verdict on the weekend in Magny-Cours?

BB:

Overall, we were extremely pleased: Fernando took a very strong second place, and was beaten only by Michael (Schumacher) in better equipment. What's more, it was no walk in the park for Ferrari: the fact they were prepared for a four-stop strategy meant they were concerned we could push them hard, and we did.

Q. Obviously, though, it could have been two cars on the podium.

BB:

Sure, but the morning after, we couldn't help but recognise that Magny-Cours was our best result so far. Jarno has to bounce back at Silverstone, and we know he is capable of that; whatever he may have felt immediately after the race, it is in the past now and he must put it behind him. Had he finished third on Sunday, he would have been a hero after driving a great race to defend his position. As it was, he learned one of the harshest lessons F1 has to offer - that you are punished for every mistake, no matter how small.

Q. Is that a significant lesson?

BB:

I think it is a timely reminder for the team: until we have completed the last lap of the last race of championship, we cannot afford to drop our guard, or lose focus on our objectives. We may have scored thirteen points in France, but we still have a fight on our hands for second, and a long way left to go this season.

Q. How are you expecting to perform at Silverstone?

BB:

When we tested there, we suffered from the familiar problem of the changeable wind direction, and the R24 seemed quite sensitive to it. However, this particularly compounded the driveability problems we were then suffering from, and significant improvements have been made in this area since then. Barcelona and Silverstone are similar circuits: having been competitive in Spain, we are reasonably optimistic for the coming weekend, but Ferrari and BAR will be quick, while McLaren now seem to be back in the mix as well, and potentially capable of taking points from any of the top three teams in the event of a lapse.

The Engineer's View, Pat Symonds

"Many years ago, the site that is now home to Silverstone race track was an airfield and naturally, these were built in flat areas. An obvious consequence of this is that they are very exposed to any prevailing winds. Silverstone is no exception, and an understanding of where the wind is coming from, and how it affects the car, is important when preparing for any event at this circuit because, as Fernando's qualifying lap earlier this year in Barcelona demonstrated, invisible and unpredictable gusts of wind can potentially have a significant impact on the handling of the car.

"A Formula One racing car is fundamentally a very sophisticated aerodynamic device, and therefore the wind plays an important part in its performance. For many years, racing cars were tested in wind tunnels with the wind blowing directly onto the nose of the car in the straight ahead position. These days, it has been understood that this is only part of the story and testing now takes place with the model at many different attitudes. One of the most important of these is to test the vehicle in yaw. Yaw can be thought of as a rotation of the vehicle about a vertical axis through the centre of the car, so that the wind, instead of blowing straight on over the nose, is coming at the vehicle from a slight angle. When one looks at the aero devices on a racing car, we can see that items such as the wing endplates, while being very effective when the wind is travelling fore and aft, also have the effect of masking the wing slightly if the air is coming from an angle, and thus reducing the amount of downforce generated once the car is turning. If the car encounters a crosswind, this induces what we term 'apparent yaw'.

"The downforce generated by a racing car is proportional to the square of its speed through the air. Consequently, if the wind is blowing towards the front of the car, then windspeed is added to wheelspeed to produce additional downforce. If the wind is blowing towards the rear of the car, then it is subtracted from vehicle speed to produce less downforce. It might be thought that the effect of wind which rarely blows at more than 20kph would not have a big effect on a vehicle that can be travelling at 320 kph, but with a racing car you are always trying to operate at the very limit of the performance envelope and hence even relatively small changes can affect what the driver feels. As downforce is proportional to the square of its velocity, a 20kph headwind - which represents a 6% increase in speed at 320kph - will actually see the downforce increased by approximately 13%, and the effect on what the driver feels will be magnified the faster he is travelling, once again because downforce is proportional to the square of the speed.

"Of course, if the wind is blowing at any angle, then not only do you have a component of the wind that may be adding to or subtracting from the total downforce, but you also have a degradation in performance due to the apparent yaw effects mentioned earlier.

"The main area for understanding these effects is the wind tunnel. The less sensitive you can make the car to abnormal wind conditions, the faster it will be, irrespective of prevailing conditions. In order to understand what the wind has done to the car, we also continuously record the 'apparent wind' the car sees using two methods. On the front of every car, you will see a pitot tube, a device that measures windspeed. The speed it measures is the combination of the true atmospheric wind and the 'apparent wind', which is the airspeed generated by the movement of the car. By comparing the airspeed velocity with the car velocity measured by wheel rotation, we can deduce the windspeed. In addition, the cars sometimes carry a more sophisticated device known as a yaw probe. This works in a similar way as a pitot tube by measuring the dynamic pressure of the wind and comparing the static pressure of the air, but with added sophistication of being able to determine the angle of the wind.

"With the wind having such an effect on the performance of the car, we obviously need to be aware of it and do what we can to mitigate its effects. From Silverstone onwards, we will once again be able to time our qualifying runs in order to be on circuit when the wind is at its lowest - a luxury the one-lap system did not afford. However, with the sessions requiring a minimum number of laps to be completed, and being short in length, occasions will undoubtedly arise when we are forced to run irrespective of the prevailing climatic conditions.

"However, it is also important for the drivers and the engineers to understand the wind conditions so they can best handle them. For example, T1 at Silverstone - Copse Corner - is one of the fastest corners of the season, taken very nearly flat. A headwind on entry is an asset the driver should exploit in order to take the corner faster, while a tailwind means he needs to exercise extra caution. The complication for the drivers comes when the wind gusts unpredictably - at this point, they must make a split-second judgement of the conditions in order to judge exactly how fast the can take a particular corner."