What a difference a rule change can make! The new tire rules are quite hard to understand, but so far they've managed to make the races much more interesting and much less predictable. The presence of a third tire compound has increased the strategic possibilities by an incredible amount and therefore the teams can easily go wrong. Due to the increased grid and more competitive cars compared to last year, the number of overtakes has doubled and after five years of gradual decline overtaking is at its record-breaking 2011 level. For the moment at least.
The 2016 tire rules give the teams the option to use the softest-compound qualifying tire in the race. Although the harder-compound tires are naturally more suitable for the race, they may even lose out to an aggressive soft-tire strategy in the race. However, there is usually not much in between the different strategies, so the compound choice is also determined by the circumstances. For example, in Melbourne many teams chose to run the hardest tire (the medium tire) after the red flag in order to finish the race without further pitstops. Although the more aggressive strategies may have been faster, they also require some overtaking on a track where overtaking is quite difficult.
In Bahrain, one of the first Tilke tracks, overtaking is not so much of a problem. Despite that, we saw a lot of different strategies in the very crowded midfield. Sadly, the battle for the lead was over after the first corner, when Bottas T-boned Hamilton. With a damaged car Hamilton could only manage 3rd, behind Rosberg and Räikkönen. Rosberg was leading by 15 seconds before the first pitstops and from then on he was managing the gap to Räikkönen, so after two races we still don't know how fast the Ferrari is compared to the Mercedes.
More interesting was the battle behind the Mercedes and Ferrari. Ricciardo, Grosjean and Verstappen were the only other drivers to finish in the same lap as the winners, while the Williamses slipped back from 2nd and 3rd after the first corner to only 8th and 9th at the finish. What went wrong? Was it a matter of a poor strategy or were they just not fast enough?
Laptime analysis
Laptimes in the race are determined by many different factors. In this analysis, I've tried to separate the strategic factors, like tires and tire wear, from the intrinsic driver speed. This should give the natural finishing order in case of equal strategies and no further delays (traffic) during the race. The tire-wear data can then be used to evaluate the chosen tire strategies. In the analysis the laps in traffic are automatically excluded, so they don't disturb the results.
Driver speed
The fastest drivers in the race were Rosberg and Räikkönen, who were equally fast. Hamilton was almost half a second slower, but it was claimed that the damage to his car cost him about a second per lap. This suggests that either Hamilton is half a second faster than Rosberg, or that Mercedes has still some pace in hand.
Despite finishing over a minute behind, Ricciardo was 4th-fastest in the race. His intrinsic pace was 0.9 seconds per lap slower than Rosberg's, which accounts for about 50 seconds of his deficit at the finish. The other ten or so seconds were lost in traffic. Verstappen and Grosjean were fifth and sixth pace-wise, but they were almost 0.5 seconds per lap slower that Ricciardo. For Grosjean it was even more impressive to finish where he did, given that he lost quite some time in the pits. Apparently he regained some time with his hyper-aggressive tire strategy. Only slightly slower was Bottas, which suggests that without the drive-through penalty he may have been able to hold on to fifth place. His teammate Massa was 0.2 seconds per lap slower, but he was still a tenth of a second faster than Kvyat, who passed him in the penultimate lap.
Strategy
In the race, fuel and tires have a profound influence on laptimes. The fuel load slowly burns off during the race and is assumed to behave the same for all cars. Yet, I was surprised that the effect was 0.07 seconds per lap. It may not seem much, but it means that the laptimes improve by about 4 seconds during the race and that's quite a lot in this turbo era, as the amount of fuel is limited to 100 kilograms for the entire race. Typical laptime improvements are 0.05 seconds per lap on medium-length tracks nowadays. Possibly the figure is inflated by the track improving during the race (rubbering in or maybe the sand got removed during the race). Anyway, the fuel load is the most noticeable signal in the data. Tire wear was high, which is not surprising. Last year, the race was a boring 2-stopper, with most drivers using two sets of soft tires and one of the medium tires. This year, the supersoft tire was available for the race, with great grip (Hamilton set a lap record in qualifying) and huge tire wear.
Based on the average of all drivers, tire wear was nearly 0.16 seconds per lap on the mediums, 0.23 seconds per laps on the softs and a staggering 0.27 seconds per lap on supersofts. The supersofts were, of course, considerably faster: they were 0.4 seconds per lap faster than the softs and 1.1 seconds per lap faster than the medium tires. Still, in the longer runs the tire compounds were performing similarly and therefore there was quite some strategic variation.
Suppose there are thee equally skilled drivers: Red, Yellow and White. Red can only use the supersoft tires in the race, Yellow only the softs and White only the mediums. Who would win? Based on the tire-wear data, Red would win, but only by 6 seconds. White is a further 7 seconds behind, but he only needs 2 stops instead of 3, which may prove a strategic advantage. So the medium tire was still slower in race-trim, but traffic or exceptionally high tire wear could easily tip the balance towards the medium tire.
The midfield battle
Let's return to the battle for 4th to 8th. All drivers were on different tire strategies: Massa was the only driver on a 2-stop strategy, while the other drivers made 3 stops and were running softer tires. Let's see how their races panned out:
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| Race History Chart of the midfield battle compared to Ricciardo's average pace. |
Massa's race started promising, but at his first stop he switched to mediums and he got passed by Ricciardo, Grosjean and Verstappen on the softer tires. After the final round of pitstops he was still ahead of Grosjean and Verstappen, but they passed him easily on much fresher tires. Even Kvyat, who had to recover from a poor grid position, managed to pass him. Interestingly, Massa's Race History Chart is quite close to the predicted (dashed) curves, which suggests that his race was relatively problem and error-free.
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| Race History Chart and traces of Ricciardo, Grosjean and Massa. |
Massa's first stint on the medium tires was quite poor. His pace was quite good for a few laps, but then he drops back significantly, so he crosses the predicted line at around lap 16. He regains some time due to a very good pitstop and in his last stint his pace is even slightly better than expected; his tire wear looks pretty good. The exact opposite applies to Grosjean, who lost quite some time in the pits, especially at his last stop. Without the delay he would have been very close to Ricciardo, who finished the race on mediums, but due to the higher tire wear of his soft tires he would have to give up the chase anyway. Ricciardo's race was pretty much as expected.
Could Massa have done better with a different strategy? Probably. Due to the high tire wear a 2-stop strategy with just a 7-lap first stint would always be a tall order. Of course Williams had to stop Massa early if they wanted to maintain track position over Ricciardo, but it meant that Massa had to do 50 laps on just two sets of the slowest tire. If he had been patient enough to stop as late as lap 16, then he would have saved 15 seconds in the race, which would still just have been enough for 7th place. With that early pitstop the best strategy was probably to do a 3-stopper on the soft tires, which would have been about as fast as the optimal 2-stop strategy. Without the drive-though penalty 5th (Bottas) and 8th (Massa) was the maximum possible for Williams, which would have been the same result as in Melbourne. Williams is just not very quick in 2016. Mercedes and Ferrari are clearly ahead and Red Bull, Toro Rosso and Haas seem to have a better race pace too.
