Japan in Depth: How different strategies are optimal for different cars

Posted on October 11, 2011

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Hindsight is a wonderful thing. It’s easy to say after the event whether strategy decisions worked out or not, but it’s not so easy to tell whether the strategy decisions taken were actually the best decisions which could have been taken. With the intelligentF1 model, the underlying pace of each car/driver combination can be calculated on each type of tyre, and the tyre degradation can be assessed, so we can determine which strategy would theoretically have been the quickest for each team. And as you might expect, the answers are not always obvious.

Let’s start with Red Bull. Another article on this site suggests that they would have been better off doing four stops, due to the high degradation on the prime tyres. Further data analysis shows that had they been brave, they could have gone option-prime-prime and done just as well, as shown in the chart below. The blue dashed line is two stops (option-prime-prime), the black line is three (3 options-prime) and the red line is four (3 options-2 primes). Admittedly if we allow for the safety car, it shifts the final stint on primes back a couple of laps and the degradation (based on other cars) is such that the four stop just becomes optimal again. The curves in the lines are where the tyre degradation becomes significant – the Red Bull option tyre degradation is such that they cannot do a three stop race without this happening.

What about a team which is easier on their tyres, like Ferrari? Well, for them the story is different. This time, as the options last 12 laps before the degradation becomes serious, and the primes are about the same amount slower (0.8s for Ferrari, 0.9s for Red Bull), Ferrari are able to use the strategy that was expected to be optimal – and it is a full 10s better than two or four stops. The chart is below, and the same lines are used for the different strategies. Same race, different car, different answer.

To complete this discussion, we look at Sauber. Their tyre wear was roughly the same as Ferrari at Suzuka, perhaps a touch better on the options and a touch worse on the primes, but the key difference is that in the hands of Perez (especially) the Sauber was quick on the prime tyres. The options were worth only an additional 0.3s of performance per lap to the Mexican. This gives us the chart below.

This time, the two stop is the optimal strategy. Interestingly, Sauber ran a two stop, but prime-option-option instead of option-prime-prime as shown here. This does not do quite as well as even the Sauber does not have the necessarily longevity of life on the option tyres – the few laps under the safety car did them a favour.

Three cars, three strategies. For one of them there was a clear optimum, for the other two a choice. But all three strategies could have been chosen (Red Bull four stops, Ferrari three and Sauber two) and justifiably considered as the best choice. So, the next time a statement is made about one team’s strategy being better than another team’s strategy, it might just be the case that they both got it right. Or both got it wrong.

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