The results of a trial at Silverstone in July to limit the amount of spray generated by F1 cars under wet conditions did not produce the intended outcomes. The wheel fairings employed in the trial merely cut down a minor proportion of the spray. More dramatic measures are necessary, claim F1 officials, to sufficiently restrict the spray and facilitate better racing in rainy conditions.
As per Nikolas Tombazis, the FIA‘s single seater director, the Silverstone trial did not meet expectations because of the design deficits in the spray guards. Speaking to F1 Initiative, Tombazis said,“What was done at Silverstone, with the assistance of Mercedes who manufactured parts and McLaren [who deployed a car for spray feedback], was likely an overambitious experiment.” The wheel’s spray guards were too limited in coverage, leading to negligible results.
Tombazis has hinted at the complexities associated with finding a solution to the spray problem. The excessive spray from F1 cars results from several factors including water shooting upwards from tyres, water accumulated between the wheel and asphalt, and water that stagnates in the ground cracks being sucked up and expelled. Tombazis commented, “We believe that the spray from the wheels contributes about 40% of the total. If we could restrict this phenomenon, it’s certain that the drivers wouldn’t have total visibility, but there would be a significant improvement.”
Reflecting on the quest for a solution, Tombazis noted that the FIA has been studying tools developed by the car manufacturing industry for simulating wet-weather conditions. However, these tools need to be accurately calibrated for optimal correlation — a difficult task due to FIA testing restrictions and assembled constraints.
While a larger wheel covering could mitigate the spray issue, it would significantly affect the car’s aerodynamics and underlying airflow. Tombazis acknowledged this fact but explained that all teams would suffer the same downfall. He pointed out that wheel fairings had variable effects on the cars’ downforce, sometimes causing a significant loss. F1 CEO Stefano Domenicali recently suggested that the diffuser could be targeted to reduce spray, but Tombazis dismissed altering specific design regions in the tyre squirt area.
Tombazis emphasized that any solution should be effortless for the teams to implement and should primarily cater to extreme wet conditions — an occurrence perhaps once or twice a year. In terms of changes to the machines, Tombazis prefers to avoid making any alterations. Instead, he hinted that other ideas might be conceived for the 2026 regulations.