Mercedes W15 side ceiling design under a microscope after the presentation of the US Grand Prix

The team that made the most noticeable improvements last weekend in Texas was undoubtedly Mercedes.

Although their weekend didn’t go as planned, with only seven points in the sprint and eight in the main race, the updated W15 still managed to demonstrate a lot of untapped potential. It’s clear that Mercedes is working hard to close the gap with its rivals, and these updates could be a decisive step in the right direction. So what exactly did Mercedes change in their car? Let’s take a closer look at the tech updates and see how they plan to turn this potential into performance.

Mercedes is finally using side ceiling intakes

The most significant change to the W15 is the addition of the popular raised-bite side-roof air intakes. This design trend, originally started by Red Bull earlier this season, has now been adopted by other teams. Although there were rumors of Mercedes implementing this feature, it took them longer than expected to apply this design philosophy to the W15.

An overbite has a longer upper edge compared to the rest of the opening. This approach aims to improve airflow through the top of the side compartment, directing it to critical aerodynamic components at the rear of the car. Thanks to this design, air flow is easier to control and can be directed more effectively to the rear elements of the vehicle.

In addition, at certain speeds, air has difficulty entering the side suspension due to increased inlet pressure. The extended top edge prevents excess air from passing through the side stand, pushing it from below towards the undercut area. This gives engineers more control over the flow of both clean and dirty air.

The overall shape of the air intake remains virtually the same, although it is now narrower, allowing for a more pronounced undercut. This increased space is probably the most extreme compared to other teams, resulting in a smaller internal area of ​​the side compartments and a likely more complex cooling system layout.

However, the increased space under the sides of the car allows for improved air flow to the diffuser and fender beam, as well as better control of dirty air from the rear wheels.

These changes are accompanied by changes to the geometry of the engine cover visible from the rear of the car. It seems that the optimal shape has been found to improve the cooling of the power unit, which is likely influenced by changes to the air intakes of the side trays.

Also arriving is the new Mercedes W15 front wing.

Mercedes has also redesigned its front wing, an element crucial to the flow of air following it. The goal is to better integrate these updates into the front end of the car. Looking back, Mercedes found form earlier this season after unveiling a new front wing at Monaco, which led to several race wins.

Although the redesign is not as radical as before, it still affects the car’s aerodynamics. One of the changes to the front wing includes the addition of a spacer element between the last and penultimate flaps. In addition, the edge of the end plate now has another aerodynamic element, likely aimed at enhancing the side-stream effect.

The side effect of the front wing is critical as it controls dirty air from the front wheels, directing it away from the car and key aerodynamic components.

Although unconfirmed, there is speculation that Mercedes (and other teams) may have also been working on wing flex, given that the FIA ​​has brought the issue under even closer scrutiny recently.

Mercedes W15: What does the data show?

Sprint qualifying in Austin showed the first positive signs of these new updates. Lewis Hamilton was fastest in the first sector, and George Russell set the fastest time in the second.

This underlined the W15’s strength on the straights and in the fast corners of the first sector. This session also saw Russell record the highest top speed of the weekend at 330 km/h. This trend continued as the Mercedes generally posted very high top speeds throughout the weekend.

However, towards the end of the weekend the situation took a turn for the worse. During the sprint race on Saturday it became clear that they were behind Ferrari, McLaren and Red Bull on race pace. Unfortunately for them, the trend continued on Sunday, with Hamilton pulled out early in the first quarter and Russell involved in an incident. The W15 felt unstable and difficult to drive.

A key indicator that something was wrong was Hamilton’s freak crash early in the race, when he completely lost control and was forced to retire. It’s rare to see such errors from a driver of Hamilton’s caliber, suggesting the car may still need more rear-end stability despite the updates.

Engineers often take time to adjust the car’s balance to accommodate new aerodynamic improvements. To further complicate matters, there was only one free training session in Austin, leaving limited time to collect data.

The next two races in Mexico and Brazil may be more in line with the W15’s current performance. In Mexico, the thinner air will have a big impact on the aerodynamics, so the main challenge for engineers will be to find the right balance and extract maximum downforce.

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