Russell’s victory was taken away from him after he was disqualified, while his teammate, the seven-time Formula 1 Champion Lewis Hamilton, inherited the win.
Simply put, according to the regulations, Russell’s car should weigh no less than 798Kg without fuel. However, when the stewards took a sample of 2.8 liters of fuel from the car, it was still found to weigh 796.5Kg, even with fuel in it. This was 1.5Kg less than the allowed weight.
In Mercedes’ race report following the disqualification, Trackside Engineering Director Andrew Shovlin expressed his sympathy for Russell and acknowledged his impressive performance. Shovlin stated, “We don’t yet know why the car was underweight after the race, but we will thoroughly investigate to find an explanation. We believe that the loss of rubber from the one-stop strategy may have contributed, and we will work to understand how this occurred. However, we will not make any excuses. It is clearly unacceptable, and we must ensure it does not happen again.”
Shovlin’s explanation regarding the loss of rubber as a potential reason for Russell’s underweight car seems to be the most plausible theory.
During a stint, a car’s four tires can lose approximately 1Kg of rubber, which teams take into account in their pre-race calculations. The Spa circuit, being the longest on the F1 calendar, combined with Russell’s longer-than-expected stint, may have resulted in even more rubber loss.
Furthermore, at Spa, there is no cool-down lap, and the cars enter the pitlane at the exit of Turn 1. This means there is no opportunity for the cars to pick up rubber marbles, which could have compensated for the lost tire weight.
Another factor to consider is that the preferred strategy for the Belgian GP was a two-stop strategy. However, Mercedes and Russell decided to improvise during the race and opted for a one-stop strategy. This means that Mercedes may not have taken into account the additional loss of rubber from Russell’s set of Hard tires used in his second and final stint.
