Belgium 2009: Post-Qualifying Car Weights

The FIA have published the measured and declared weights of all the runners and riders for tomorrow’s Belgian Grand Prix. With a Force India on pole position, it had been expected that Giancarlo Fisichella was light on gas. As you will see in just a moment, the Italian is not that skinny, and in P2, Jarno Trulli is heavier and poised for a Trulli-train; Rubens Barrichello is probably kicking himself right now.

If we take Williams’s figure of 2.25kg of fuel needed to cover a normalised distance of 5km, we can figure out that a Formula One car will on average use 3.15180kg of fuel to complete a 7.004km lap of Spa Francorchamps. Allowing for a couple of laps for grid formation and margin and taking off the minimum weight of the cars, we can guess when the drivers will first call into the pits for fuel and tyres, assuming the weather is dry and the safety car remains at the end of the pitlane.

Belgium 2009 Post-Qualifying Car Weights		Car Weight Kilograms	Fuel Weight Kilograms	First Stop Estimated Lap
1.	Giancarlo Fisichella Force India	648	36.7	12
2.	Jarno Trulli Toyota	656.5	45.2	14
3.	Nick Heidfeld BMW	655	43.7	14
4.	Rubens Barrichello Brawn	644.5	33.2	11
5.	Robert Kubica BMW	649	37.7	12
6.	Kimi Raikkonen Ferrari	655	43.7	14
7.	Timo Glock Toyota	648.5	37.2	12
8.	Sebastian Vettel Red Bull Racing	662.5	51.2	16
9.	Mark Webber Red Bull Racing	658	46.7	15
10.	Nico Rosberg Williams	670	58.7	19
11.	Adrian Sutil Force India	678.5	67.2	21
12.	Lewis Hamilton McLaren	693.5	82.2	26
13.	Fernando Alonso Renault	684.4	77.4	25
14.	Jenson Button Brawn	694.2	82.9	26
15.	Heikki Kovalainen McLaren	697	82.2	26
16.	Sebastien Buemi Scuderia Toro Rosso	685	73.7	23
17.	Jaime Alguersuari Scuderia Toro Rosso	704.5	93.2	30
18.	Kazuki Nakajima Williams	706.1	94.8	30
19.	Romain Grosjean Renault	704.7	93.4	30
20.	Luca Badoer Ferrari	691.5	80.2	25

From the table we can see that Fisichella is not the lightest of the front runners and in fact Rubens Barrichello should be calling into the pits before him. Fisichella is on par with Robert Kubica and Timo Glock, and only a couple of laps lighter than Jarno Trulli, Nick Heifeld and Kimi Raikkonen. If Rubens is to have an impact on the leading trio, he will need to make up places on the first lap, otherwise he could find himself stuck behind the slower BMW and Toyota.

The top ten all seem to be on a two-stopping strategy (although Nico Rosberg remains flexible), and the bottom ten all seem to be attempting a one-stop strategy. The heaviest driver on the grid is Kazuki Nakajima, closely followed by Romain Grisjean and Jaime Alguersuari. The lightest car starting the race tomorrow is Rubens Barrichello, which just highlights the problems facing the Brawn team at the moment.