Why F1's floor change could lead to unintended consequences

Aerodynamic development will not be frozen though, with the cars likely looking very different from race to race as designers relentlessly pursue performance.

But one aspect of the car's design that will immediately stand out as different across the board in 2021 is the new floor shape, which the FIA has introduced to try to cut downforce by around 10%.

The motivation behind this move is to help F1’s tyre supplier Pirelli, which plans on continuing to use the same tyre construction and compounds for the third season in a row.

Without this intervention from the governing body, it was expected that the teams would continue to ramp up downforce in this area and that could potentially create a situation where the tyres couldn’t cope with the associated loads.

The outcome is a two-fold change in the rules, the first of which looks to resolve a regulatory mishap that’s allowed fully enclosed holes to be placed in the outer 100mm of the floor since 2017.

2021 floor rules

Photo by: Giorgio Piola

The second takes a diagonal slice out of the floor and will compound the issues faced by the designers as they attempt to shield the floor and diffuser from the turbulence created by the wheels.

Floor holes

The proliferation of holes we’ve seen added parallel to the floor’s edge and those angled ahead of the rear tyre in recent years have similar but different aims.

Haas-Ferrari VF-20 floor detail

Photo by: Giorgio Piola

The holes added parallel to the edge of the floor create an aerodynamic buffer, an air skirt as such, that protects the airflow on the underside of the car from the wake turbulence created by the front wheels. 

Haas F1 Team VF-20 diffuser

Photo by: Giorgio Piola

Meanwhile, the angled holes, just ahead of the rear tyres, help to mitigate the impact of ‘tyre squirt’ - a phenomenon caused by the deformation of the rear tyre and airflow that is squirted laterally into the path of the diffuser.

Taking away these design aspects entirely means the designers will go off in search of ways of recovering the losses elsewhere, and that’s where teams’ innovation could cause headaches for the rule makers in their hopes of cutting downforce.

For by removing an obvious and visible mechanism for creating the effect, it has effectively replaced it with many potentially unpoliceable development avenues instead.

As a result we’ll undoubtedly see substantial changes to the leading edge of the floor, the bargeboards and a whole host of other surfaces just to counter their removal. It is expected that they’ll already have overcome the 10% downforce loss by the time the teams reach the first race in 2021.

Obviously this development isn’t for free and comes at a time when F1 is set to adopt a cost and resource cap like we’ve never seen before.

Perhaps a better interim solution, seeing as we’re talking about just one year’s worth of development, would have been to lessen what could have been done on the floor’s periphery.

This may not have met the 10% reduction target, but it may have led to a less costly development race to recover those losses through the adaptation of other parts and flow structures on the car.

The other issue is that whilst it’s widely accepted this will initially create a drop in downforce, it’s not guaranteed it won’t have other unintended consequences that actually lead to more downforce being found had the changes not been introduced.

2020-2021 floor comparison

Photo by: Camille De Bastiani