At Mercedes, its new floor appeared to have delivered some good potential, but there remains a degree of uncertainty about what we actually saw following Lewis Hamilton’s post-race disqualification for plank wear.
Meanwhile at Aston Martin, its latest developments were clouded by the team suffering major brake problems in FP1 that left it unable to get a proper feel for things.
It took the bold step of starting both its car from the pitlane, and even abandoning the new parts on Fernando Alonso’s car, to help fast track its understanding.
Haas also started its cars from the pitlane because it felt that the settings it had committed to after FP1 were far from ideal.
This is why all three teams will be hoping the more normal timetable in Mexico this weekend will allow them a lot more time to get to grips with the changes.
Here, we take a deeper look at the changes the teams made.
Mercedes floor
The floor update introduced by Mercedes was not isolated to just one particular area.
Instead, it extended to several different aspects, which resulted in a compound performance gain, as each of those new components worked in unison to yield more than the sum of their individual parts.
Externally we can see where the changes have been made but, with the bottom of the car remaining hidden for now, we are unable to see how the underfloor’s volume has been affected.
However, there are some clues, with the blisters on top of the floor having been moved around and/or optimised indicative of the space that’s also created beneath.
The additional and repositioned volume created here provides more flow by virtue of the floor’s leading edge having been raised. The inboard fences have also been optimised both in shape and position.
Meanwhile, the outer fence also features a number of tweaks, not only to its angle relative to the ramped section but also in terms of the detail ahead of that transition. The tall step that had previously dominated this region gives way to a softer feather-like profile.
On the edge of the floor, Mercedes has made further changes to increase load, with the scrolled front portion of the edge wing modified once more.
Altering the height and shape of the scrolled section has also been married with a change to the vanes housed upon it, as their shape and orientation have been adjusted to better interact with the changes made to the floor and associated elements ahead of it.
Mercedes also followed in Alpine’s footsteps from a few races ago, as it implemented a similar old school method to check that the region was performing the same way in the real world as it had during their CFD and wind tunnel tests, utilising tufts (main image, red arrow).
Aston tweaks
Aston Martin also updated its floor edge and edge wing design for this race, with the team employing an external variant, rather than the underfloor one it has used so far this season.
It is in a similar style to many other solutions seen up and down the grid, with the forwardmost section rolled up and additional vanes added to help guide the airflow.
Unlike its rivals, which have opted to create more of an exaggerated twist in the forward portion of the edge wing, Aston Martin has gone for a gentle curvature along the length of the edge wing.
Furthermore, where many of its rivals have opted to taper the floor edge and the edge wing in the latter half, Aston Martin has not, resulting in a much larger tyre spat deck.
Allied to the floor changes are some alterations to the sidepods too, as the front undercut has been made deeper, with the frontal bulge removed as a consequence.
Downstream of this, the gutter undercut has also been reprofiled, providing a wider passage for the air to move to the rear of the car.
Haas goes downwash
Haas introduced a significant update package for the United States Grand Prix, as it became the last team to make a wholesale conceptual shift from its original sidepod design in favour of a downwash ramp-style solution.
It also opted to increase the longitudinal disparity between the upper and lower lips of the sidepod’s inlet, following the same methodology that Red Bull has employed, whereby the lower lip of the inlet sits much further forward than the upper lip.
This helps to construct a more effective passage for both the airflow into the inlet and the sidepod’s undercut, which has also benefited from the alterations as the surface has been shrink-wrapped closer to the internal components.
This is made more obvious by the appearance of a blister on the lower face of the undercut, which has been formed around the lower SIS that’s located in this higher position on the VF-23. Many of its rivals have slung it down lower and have disguised it within the floor.
The downwash ramp bodywork is also complemented by a waterslide or gully system, albeit it’s the gentler approach we saw many take originally, not the deeper option that the likes of Aston Martin, Alpine and McLaren now have.
Meanwhile, cooling has also been revised with much more emphasis placed on the shoulder of the engine cover, as the cooling gills have been moved to this region, rather than being located in the bathtub-like crevice atop the sidepod bodywork they had previously.
Alfa continues upgrade programme
Alfa Romeo also made changes to its floor edge for the US Grand Prix, with a much taller and longer scrolled edge wing employed in the second phase of the floor’s edge.
This is complemented by an elongated floor edge cutout thereafter, with the edge wing continuing to run alongside it, right up to the rear tyre spat deck.
Similar to designs seen on its rival’s cars, the tall and elongated scroll will undoubtedly help to load the region and help work other sections of the floor more effectively as a consequence.
