A deep dive into strategies from the Spanish Grand Prix
This year's Spanish Grand Prix at Barcelona was widely heralded as one of the most exciting largely due to the way strategies played out, meaning t...
This year's Spanish Grand Prix at Barcelona was widely heralded as one of the most exciting largely due to the way strategies played out, meaning that an intense battle for the lead developed in the final third of the race.
Also we saw the pole sitter Mark Webber dropping to fourth place, Fernando Alonso, the leader on lap one, finishing in fifth place a lap down on the winner and the recovery of Jenson Button, from tenth place on lap one to finish on the podium thanks to a bold strategy variation.
Pre race Strategies
On paper going into the race if a driver had new tyres to use, a three-stop strategy was four seconds quicker than a four-stop.
But few drivers had the luxury of new tyres, most had one new set of softs at best. On old rubber, a four-stop was showing to most strategists as being 10 seconds quicker. So there wasn’t much in it, which is why you saw drivers doing different things and ending up in pretty much the same place, with the exception of Button.
The overriding consideration for engineers and drivers was that the new hard tyre was a lot slower than the soft. The gap between compounds was around two seconds per lap in practice and that came down to just over a second as the track rubbered in. So the stints on hard tyres were quite compromised. Drivers wanted to spend as much time on soft as possible.
But the degradation was such that by half distance some cars, like Webber and Alonso had already made three stops and so were destined to spend the second half of the race on the hard tyre.
The importance of new tyres
Once again we had several graphic illustrations of how new tyres make a massive difference. We saw some key positions change due to the 'undercut', where a following driver pits a lap before the car in front and gets ahead of him.
Sebastian Vettel used the undercut to pass Fernando Alonso for the lead. Vettel pitted early, on lap 18 and his out lap on new tyres was so much faster that when Alonso pitted a lap later, Vettel was through to lead the race. It was crucial for Vettel to get past Alonso in this way as Lewis Hamilton was running longer stints and was looming as a challenger for the win as he was on tyres which were four laps younger than Vettel's.
By pitting early on lap 18 and getting clear of Alonso, Vettel was able to stay ahead of Hamilton at the third pit stops on lap 34/35, when the drivers switched to hard tyres. We have observed Red Bull always tend to pit on the early side, before the tyres start to really lose performance, it is built into their tactical thinking. McLaren in contrast, are willing to run a little longer on the tyres and it brings them very close to Red Bull. In Spain by running a few extra laps they managed to keep their drivers in clear air, where in contrast Red Bull compromised Webber's race early on by bringing him out in traffic after his first stop on lap 10 (see below)
Another clear illustration of how much new tyres count was Nick Heidfeld who started at the back of the grid after a problem in qualifying and managed to use new tyres all race and almost passed the Mercedes in 6th and 7th places at the end. This is what Mark Webber did in China and Kamui Kobayashi did in Turkey. It won't work so well in Monaco where traffic will slow down such progress.
Could Hamilton have used strategy to beat Vettel?
Some people have questioned whether Hamilton might have passed Vettel at the third stop had he stayed out on soft tyres a lap or two longer when Vettel switched to hards.
The analysis shows that in the laps from 34 to 36 Vettel's in laps to the pits and out laps were two seconds faster than Hamilton's. Their pit stop times were almost identical, but Vettel's first flying lap on new hard tyres was fast enough to make the difference at 1m 28.563. Hamilton had been doing 1m 30.0s on his worn softs, so he would not have passed Vettel by staying out at that pace.
However in a comparison of McLaren and Ferrari, McLaren knew that Hamilton's pace was better than Alonso's even on worn tyre so they nursed tyres and literally shifted everything toward the end of 2nd stint.
The worn soft tyre on Hamilton's car was faster than the fresh soft tyre on Alonso's car between laps 19 and 21.
Hamilton's soft tyre showed a degradation rate of 0.1625sec/lap in the first stint. But McLaren were 0.5sec quicker than Ferrari on soft tyres in the race trim so going longer than Alonso was marginal, but worked for him.
How Webber's strategy was compromised early on
Mark Webber started from pole position, looking for the win which would kickstart his season. But he ended the race in fourth place. How did that happen?
Webber's strategy was compromised at the start when he was passed by both Alonso and Vettel into Turn 1. Webber's starts this year have been a problem; in five Grands Prix he has dropped a total of 10 places, so an average of two per race.
To compound the problem by losing position to Vettel, it meant that Vettel had first call on pit strategy so he came in first on lap 9, with Webber forced to wait until lap 10. When he rejoined he was in traffic behind Petrov and Button and this allowed Hamilton who pitted on lap 11 to undercut him, dropping him to fourth.
After that his problem was being unable to pass Alonso who stayed in front of him after the second stops on lap 19. From being four seconds behind Vettel at that point he went to 11 seconds behind in 10 laps.
He was pitted very early next time around - on lap 29 - and had the tactical advantage of being behind Alonso, so he could surprise him by diving for the pits when it was too late for Ferrari to react.
But the element of surprise was lost; Ferrari read it and pitted Alonso at the same time. Red Bull's Dr Helmut Marko has since claimed that Ferrari were listening to Red Bull's radio which he claims is the only way they could have known the plan, but this has not been confirmed.
It was the right thing to do, to try to undercut Alonso. But it was a sacrifice, as that was Webber's only new set of soft tyres and they had only done ten laps. They could easily have gone on for another five or six laps (as Vettel's did on that stint). It had a knock on effect on the rest of his race and cost him the podium to Button.
From Ferrari's point of view they burned through their soft tyres very quickly, covering other people's strategies. The result was that Alonso had no soft tyres left from with 37 laps still to go. In contrast McLaren managed to get Hamilton six laps further and Button only went to hards with 18 laps to go.
How Button went from 10th to the podium on three stops
Jenson Button had a disastrous start from fifth place on the grid and was 10th at the end of lap one. He passed Buemi for ninth.
McLaren decided to stop him just three times and on a used set of soft tyres he managed to get to lap 14, the ideal window for a first stop on that plan, dropping around 8 seconds to the leaders by doing the extra four laps. But it was the platform for his successful strategy as he managed to carry the advantage of being on newer tyres than his rivals through the race. He came in seven laps later than his rivals at his second stop and 13 laps later for his third.
The delayed first stop tactic brought him out in sixth place, having jumped Massa, Rosberg and Schumacher, who had lost time behind Petrov.
He got 16 laps out of his new soft tyres (compared to Webber's 10 laps)
By stretching it out like this without losing too much time, he was able
to go to hard tyres at the same time as Webber, so was not in danger of attack. Also the McLaren turned out to be faster than Red Bull on hard tyres so he was home and dry on the podium.
* The UBS Strategy Report is prepared with input and data from several of the strategists from leading F1 teams.
The graph below is the visualisation of the FIA's official Race History data sheet.
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 or doing a pitstop. The rest show how gaps between the other drivers grew.
Graph 2 - Spanish GP lap times
Red Bull still in control but McLaren closes in
Costa loses job at Ferrari