Strategy wise, this race didn’t turn out as expected. The key consideration for the strategists on Sunday was thermal degradation of the tyres, especially the rears. This is due to the surface temperature of the tyres being very high, due to braking, traction and very heavy fuel loads at the start. With Singapore being a high fuel consumption track, cars were over 10 kilos heavier at the start than for the average F1 race.
Before the race, the talk was of three stop strategies at the front and so it proved for the leading four cars, but the way they did it was not forseen and had the Safety Car stayed out a little longer than the four laps it circulated for, we might have seen some strategists switching to a two stop. There was however one driver who made a two stop work and he set an example early on which led all the leading teams to react and copy him.
As the tyre covers came off the cars on the grid, 10th placed Paul di Resta’s car caught the eye immediately. He and his team had opted for the soft tyre, while all the other top ten cars were starting on supersofts, including his team mate Adrian Sutil (9th) and Mercedes’ Michael Schumacher (8th), both of whom had the choice of what compound to start on because they didn’t set a lap in the Qualifying 3 session. This race strategy was planned on Saturday before qualifying even started.
Force India had realised in practice that they had good race pace and some hints that they might even be faster than Mercedes over the race distance, even if they were half a second slower in Q2. They had noticed that Mercedes were struggling with tyre degradation, as they have for most of the season and reasoned that by starting on the harder tyre they would be able to do one less stop than the Mercedes. They also had an inkling that the difference between the soft and supersoft might turn out to be less in the race than others imagined and it was the key to their race.
With this strategy in mind they opted not to run in Q3 and then Di Resta planned a longer first stint on a new set of soft tyres. Meanwhile the cars he was racing against, Sutil, Schumacher and Rosberg, all started on used supersofts. Sutil had to do so because he had used two sets of supersofts in Qualifying 2. This proved to be a problem for him in the race as he couldn’t quite go long enough on the used set in the opening stint. The Mercedes meanwhile was also slightly limited by having a smaller fuel tank, so would not be able to use the blown diffuser to best effect as it consumes a lot more fuel.
Rosberg had to pit early on lap 9 and Sutil on lap 11, while Di Resta went to lap 19. But what had been apparent to Force India was now apparent to everyone else; that they could keep a good pace on the soft tyres relative to the supersofts. During the first stint of the race everyone else realised that this was the way to go. So Vettel, Button, Webber and Alonso all put new soft tyres on at their first stop, not what Pirelli had predicted at all. Instead they were all reacting to what Di Resta was showing them.
In the opening laps Sutil was faster, but by lap six Di Resta was matching and beating his lap times. As the supersofts suffered thermal degradation with the heavy fuel loads, especially the rears, it was clear that Di Resta was on the best tyre.
The Force India cars got ahead of Rosberg when the Mercedes driver had to make his second stop on lap 22. Then, on supersoft tyres that were eight laps younger than Sutil’s softs, Di Resta passed Sutil on lap 26, crucially before the safety car came out for Schumacher’s accident. Both Force India cars pitted under the safety car, as did Rosberg, but the team had to hold Sutil as Perez was coming in and this lost him four seconds and a place to Rosberg. Now all three on new soft tyres, Di Resta drove away from the other two in the long final stint to record a career-best sixth place. Looking back, it’s surprising that more drivers didn’t start on the soft. Only the Virgin drivers, Kobayashi and Petrov did it. Force India certainly thought Perez would do it, given his strategy choices this season.
The question arises, why did Schumacher not do the same strategy as Di Resta, given that he had the choice? Unlike Di Resta, Schumacher had saved a new set of supersofts and he was clearly on a “fastest possible race” strategy of three consecutive stints on supersoft and then a final stint on softs. This “sprint” strategy called on him to push very hard and, as we saw, he pushed a little too hard, hitting Perez on lap 29 and triggering the safety car.
Who was helped by the Safety Car?
Wherever there is a Safety Car there are always winners and losers. Lewis Hamilton was helped by it as it allowed him to close up after losing so much time with extra pit stop for a nose change and then a drive through penalty. By lap 15 he had been in the pits three times.
It also helped the leaders because the slower traffic was a real problem and the Safety Car bunched everyone up at mid distance, meaning the leaders had to make half the lapped traffic passes they would otherwise have had to make. Although it helped Button by cutting Vettel’s lead of 18 seconds, the revised rules on lapped traffic meant that he had Trulli, Liuzzi and Kobayashi between himself and Button at the restart. By the time Button had cleared them all Vettel was 10 seconds clear of him.
And to round out a day of “reactive strategy” in the final stages of the race, we saw the leading teams covering each other as they stopped for a set of supersoft tyres; so when 3rd place Webber stopped on lap 47, 2nd place Button covered him on lap 48 and then the leader Vettel covered him on lap 49.
Although he gave himself a shot at a podium with another fine start, Alonso was unable to do much on strategy as the Ferrari was slow on both types of tyre, unlike Monaco and Hungary where it had been relatively competitive on the same tyres. Here the tyre degradation was worse for Ferrari than expected which pushed them into running only the opening stint on supersofts and then the other three stints on softs.
The Strategy Report, brought to you by UBS, is written by James Allen with data and input from strategists and engineers from several F1 teams.
Showing gaps behind leader; The zero line is simply the race winner’s average lap time (total race time divided by the number of race laps). This is why his curve can go above the line if he’s lapping faster than his average, and below the line if he’s slower than his average, (under safety car or doing a pitstop).
Note the drop off in performance towards the end of the race as Di Resta, Sutil, Rosberg try to get to the finish on tyres they have had on since the Safety Car period. Note also the alarming drop off in performance of the Renault cars (yellow lines), taking them into the grasp of the Lotus cars.