THE DATA SET
“Inside the Race” features performance-based analysis of selected races during the Formula 1 season. The data set utilized for the features are the lap charts supplied by the FIA’s official timing and scoring reports. Only representative race laps are included in the analysis as the focus is primarily on evaluating on-track performance; therefore, laps skewed by pit stops, safety car periods, or significant on-track incidents are not included.
Race analysis for Round 2 of the 2010 FIA World Championship, the Australian Grand Prix, was run for a total of seven driver/entries, including the top six finishers of the race as well as Mark Webber who finished the race in 9th place:
- Jenson Button : Vodafone McLaren Mercedes : 1st Place
- Lewis Hamilton : Vodafone McLaren Mercedes: 6th Place
- Nico Rosberg : Mercedes GP Petronas : 5th Place
- Mark Webber : Red Bull Racing : 9th Place
- Felipe Massa : Scuderia Ferrari Marlboro : 3rd Place
- Fernando Alonso : Scuderia Ferrari Marlboro : 4th Place
- Robert Kubica : Renault F1 Team : 2nd Place
- The first line plot is intended to address two primary issues which emerged during the Australian Grand Prix, as evidenced through the performance of the two McLaren teammates: (1) the differences between the ‘optimal’ one-stop strategy of Jenson Button and the ‘optimal’ two-stop strategy of Lewis Hamilton; and (2) Lewis Hamilton’s criticism of McLaren’s decision to place him on a two-stop strategy.
- The conditions in Melbourne on race day provided a reasonable opportunity for teams to try and split strategy between drivers and opt for a one or two-stop strategy. However, with the first round of pitstops occurring within the first 10 laps of the race, it might be better to characterize the two options as a one or no-stop strategy.
- It’s hard to fault McLaren’s decision to pit Hamilton on lap 32 after Mark Webber forced Mclaren’s hand by stopping on lap 31. Hamilton was losing considerable time behind Robert Kubica and the times set by Michael Schumacher on fresh rubber pointed to a significant pace improvement that would pay for the pit stop in less than 15 laps. In fact, McLaren waited too long to make the decision as Webber was able to temporarily leap-frog Hamilton. Even though the decision didn’t work out in the end, going with the same strategy as guys like Ross Brawn and Patrick Head doesn’t exactly qualify for “bonehead” status. Nothing ventured, nothing gained.
- The second and third line plots show the battle behind Jenson Button, with the second plot displaying the full race distance and the third giving a more detailed look at the second half of the race. A couple of interesting trends pop out from the plots, especially after Nico Rosberg and Lewis Hamilton both pitted for their second stops and the results of the one vs. two stop strategy decisions became evident. Two distinct time brackets emerged: the one-stoppers lapping between 1:30 and 1:31, with the two-stoppers running between 1:28.5 and 1:29.5. Notice that 1:28.5 seems to be the absolute floor that the two-stoppers could run to. The decision by McLaren and Mercedes GP to pit their drivers had paid for itself in around 13 laps, but catching the drivers ahead and passing them turned out to be two distinct tasks.
- Perhaps the most intriguing bit of information gleaned from the line plots is the gradual slow-down of Hamilton’s times as he completed lap 49; suggesting that his tires going off, and not an inherent inability to pass, resulted in him eventually spending several laps behind Fernando Alonso without finding a way past the Ferrari driver. The implication is that what was first theorized in the Inside the Race edition for the Bahrain Grand Prix is true: the Bridgestone tires, if coaxed along, can run for an extraordinarily long distance with relative consistency. On the flip-side, if a driver pushes the tires to their performance limit, it appears that the performance life of the tires is quite short. Bridgestone officials stated after the race that the drying conditions allowed for exceptional tire life above and beyond what would be possible in a dry race; but after two rounds, a pattern is emerging regarding tire operating envelopes. Stay tuned.
- Power trend lines were set against the post first stop data set for Jenson Button and Lewis Hamilton, as well as against the second-half of the race for the split of one and two-stop runners in the second plot. What is clear from both line plots is that lap time trends were remarkably uniform dependent on which strategy the driver chose.
- Possibly confirming the tire performance envelope theory is the fact that lap time trends for drivers utilizing their second set of Bridgestone tires mirrored the trend of those who didn’t stop; albeit quicker by about a second. Accounting for identical fuel burn-off rates, the trend line for Rosberg and Hamilton should have dipped much steeper if their tires could be pushed to the limit for a reasonable number of laps without deteriorating.
- For those unfamiliar with box plots, the upper and lower ‘T’ lines show the minimum and maximum lap-times. The upper and lower reaches of the bars show the first and third quartiles of the lap-time data set (or in other words a 25-75% range), while the center ‘+’ denotes mean lap-time.
- The first graph displays the performance of the top six finishers for the duration of the race, while the second plot focuses on the one vs. two-stoppers during the second half of the race.
- Jenson Button’s remarkable consistency is evident in the line plots is also on display in the box plot, as the box representing his quartiles is especially compact and the least skewed away from his mean lap time.
- The true extent of the pace provided by the two-stop strategy is evident in the box plots of Rosberg and Hamilton, as both drivers’ first quartiles dip down to the fastest laps set by the one-stoppers. The second graph further shows the significant difference in lap times between the two sets of drivers during the second-half of the race.
- In closing, two driver/entry-specific notes: (1) Robert Kubica’s pace from Bahrain and now Australia seem to indicate that Renault have a very capable package that sees them nipping at the heels of the “Big Four”; (2) even though Mark Webber and the rest of the Red Bull Racing team had a race to forget, the impressive pace of the RB6 Renault is clearly evident in the second graph.
posted by Trey Blincoe