With it having become obvious to teams just how much extra performance is being produced by underfloor aerodynamics, both opted to make changes in this area of the car for the French Grand Prix.
And it appears there is an intriguing detailed development battleground opening up between them when it comes to trying to maximise how the airflow is directed towards the floor by fences.
Red Bull, having run the twin outer fence arrangement since the start of the season, decided to abandon it as part of its latest update. Instead, the inner of those two fences was moved further inboard.
Placing the third fence in closer proximity to the two inboard of it not only has an impact on the behaviour of the airflow as it enters the tunnel, but it will likely also result in this third fence stretching back underneath the floor like its siblings inboard.
Previously it had stopped short to help power up the vortex structure produced by the outermost fence.
This fight between the two uses of the third fence also means that it’s not as tall as it was before, instead sitting within the bounds of the leading edge’s floor line, rather than above it, in order it worked in conjunction with the outermost fence.
Red Bull RB18 rear brake duct comparison
Photo by: Giorgio Piola
Red Bull also made a subtle change at the rear of the car, with an additional vane added within the bounds of the rear brake’s inlet scoop (red arrow, old specification inset).
The result of the changes will be minimal but will facilitate a better route for the airflow to take into the pipework alongside which feeds the caliper.
Ferrari F1-75 turning vanes comparison
Photo by: Giorgio Piola
The changes made by Ferrari were also focused on the tunnel entrance for the underfloor, with visible changes made to the height of the floor’s leading edge and the fences.
As we can see in the comparison, above, Ferrari has decided to create more of a two-tier arrangement, with the inner portion of the floor’s leading edge remaining nearer to the upper limit imposed by the regulations, whilst the outer section has been flattened out.
This lowering of the tunnel entrance in the outer section also means that the upper surface of the floor is now divided into two sections, with the lower section more or less aligned with the edge of the sidepod and the inner portion feeds into the sidepod’s undercut.
There’s also changes to the outer fence, as it’s both taller and has been extended forward. There’s also a…