Australian Grand Prix: Race Notes

Posted on March 18, 2013

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I must admit to a feeling of quiet satisfaction whilst watching the Australian Grand Prix. From the Friday practice data, Ferrari and Lotus looked to be at least as fast as the Red Bull over a race stint, and the Lotus looked good on its tyres.  So I was looking to see what the Ferraris and Lotuses were doing when we got to about lap four. And sure enough they started catching the Red Bull in front. By the time Kimi went long in the second stint, the die was cast – there was only going to be one winner.

The difficulty with the Friday data is that you don’t know the fuel loads exactly, and there are times when a team is much faster (or much slower) in the race. However, after doing the analysis for the Spanish Grand Prix last year and (wrongly) assuming that the fastest car (Maldonado) must have been running light, I did a little work to check how well the Friday times stack up against race pace. And it suggested that there are occasionally significant differences (for example Red Bull did run heavy on the Friday in Korea), but in general the Friday pace is a very good indicator of the Sunday race pace. I didn’t want to miss another Maldonado, and although Raikkonen was less of a shock, it looks like most people talked themselves out of suggesting that Lotus might win even with their fast Friday pace. I decided that I wasn’t going to do that.

And so, on to Sunday, where there were some things which were quite different from last year and from practice. First, the degradation in the race was much closer to the degradation in the race last year (with the exception of the ‘graining phase’) then the degradation seen in Free Practice. Secondly, the race pace was slower (just) than last year, despite the indications (not definite as FP3 and qualifying itself were damp) being that the qualifying pace is faster, which must be all to do with the new Pirelli tyres – and the fact that the ‘golden lap’ is very significant.

What I will do in this post is to highlight a few features of the race using the race history charts (which I will try to make clearer…). I will follow-up with a post giving the underlying pace for each car on each tyre type.

From the opening 20 laps of the race, we can see a few interesting pointers on the way the cars use the tyres. The chart below shows the progress of the first five finishers (plus Sutil) during the opening laps. Each line represents a car – cars ahead appear above cars behind, and the steeper the line, the faster the car is going.

2013_australia_2

The first thing to note is that Vettel’s pace on new tyres is fast for both his stints. This confirms that in terms of pure pace, the Red Bull is the fastest car, but this is not the case over a stint.The change in gradient in Vettel’s curve shows that he has used the best of his tyres by lap 3, and then he settles to a new pace – which is what I curve fit for the stint pace. My understanding is that this slower pace is caused by the tyres graining (balls of rubber forming on the surface as the tyre slides across the track).  This effect is also seen in the data from the other cars, and caused the initial pitstops.

The Mercedes cars lasted longer into the stint before they saw the pace drop-off, but they kept going through this phase (Hamilton coping much better than Rosberg) and were rewarded as the tyres cleaned up and showed good pace again. Very interesting is the fact that the impact on Raikkonen was very small – Lotus clearly have a car which is good on tyres, and this seems to be more effective the softer the tyres.

Sticking with the first four cars, the chart below shows the way the race panned out.

2013_australia_3

Once the cars had made the first stops, it only took a few laps to come across Adrian Sutil going long on the harder tyres. This slowed the pace, and showed Raikkonen’s hand. He easily has the pace to catch the cars ahead, but he sat back until Sutil had stopped. Then he showed his real pace (which is roughly the same as the Ferrari/Red Bull pace – although he may have had some in hand) on the harder tyre – the difference being that he could keep the tyres alive much longer.  Once he was on two stops, he was clear to win.

Key to Alonso beating Vettel was his pace at the end of the third stint. Not only had he successfully undercut Vettel at the beginning of the stint, but after having looked after his tyres well at the start of the stint (the undercut is powerful enough to tyre preserve and gain places), he was then able to unleash pace at the end of the stint – Vettel tried to go with him, but didn’t have the tyres left.

And one last thing from this chart. Alonso ahead of Massa – Ferrari favouritism, better strategy, pace? Well, without the strategy, Alonso may well not have passed Massa, but once past, there is no question that Alonso was the quicker Ferrari driver in the race. The curve fits are quite conclusive.

So what to make of it all? Let’s hope that the performance of the tyres continues to play a role in the races, because at the moment we have an ideal situation where the pecking order on pure pace is Red Bull, Ferrari, (Mercedes), Lotus and the race pace order is Lotus, Ferrari, Red Bull. Could make for some fun races.