Could Mercedes run radical 'zeropod' F1 design?

While having no sidepods at all is somewhat detached from reality, there’s good reason to suggest that Mercedes will introduce a new package that shrinks the W13’s considerably more than the ones that the team benchmarked for performance in Barcelona.

In order to imagine the direction Mercedes might be travelling in, we only have to look as far as Williams – its extreme sidepod and engine cover design features one of the shortest sidepod solutions on the grid (main image, above).

In the case of Williams, it has also been equipped with a pass-through duct, which collects airflow in the upper portion of the sidepod inlet and passes it out through the outer, upper corner of the bodywork, helping to frame the flow around that portion of the sidepod (blue arrows in the animation, below).

In order to achieve this narrow-body effect, Williams has jumped on another bandwagon that’s been growing in appeal up and down the grid: Saddle coolers. Red Bull, Alpha Tauri and McLaren have all used more expansive solutions in this regard over the last few years, in an effort to reduce the size of the sidepods by mounting larger coolers above and around the power unit (white arrows in the animation).

This obviously comes at the expense of having weight, normally situated lower in the car, in a much higher position but, as we know, everything in Formula 1 is about finding ways to gain aerodynamic performance, no matter the trade-off.

Mercedes will unveil its highly anticipated upgrades during this week’s second test but the cooling system of the car may remain unchanged, with the team focusing its efforts on producing a more aerodynamically-efficient bodywork package overall, instead of moving to the saddle configuration.

This new package will also be aided by the Silver Arrows’ approach to its chassis design and how this allows it to install the radiators within the sidepods. Using the Williams as an example once more, you’ll note the dotted line in the animation shows the triangulated shape of the chassis, which is designed to accommodate the fuel cell, energy store and connecting points for the power unit.

Over the last few years, Mercedes has taken an interesting approach to the design of this region of the car, sculpting the chassis in order that the radiators tuck in and reduce the sidepod’s overall width as a consequence and it seems that the W13 also shares this DNA.

One aspect of the sidepod's design that everyone has had to overcome this year is the presence of the Side Impact Spars (SIS), with the regulations governing their position altered when compared with the last few seasons. The intent from a regulatory perspective was that the teams would adopt a more conventional shape with the sidepods and inlets.

However, having improved upon the idea first used by Ferrari in 2017, whereby the upper SIS was slung into a low and forward position and the bodywork used as an aerodynamic fairing around it, all of the teams converged on this solution in 2021.

As a consequence, the teams will not easily forget the advantages this offers and many of them have come up with interesting solutions in order to accommodate a design which leans heavily on their experience.

As part of this design scheme, the overall width of the sidepods are largely dictated by the SIS, something that cannot be ignored and must be faired-in in some way. In the case of the FW44’s sidepods it helps with the design of the passthrough duct, as the uppermost SIS creates the horizontal divide within the inlet.

In the case of the Mercedes that was presented in Barcelona, it did not go to the absolute extremes of some of the others on the grid, whereby the bodywork very tightly wraps around the outer end of the SIS, creating a blister, so this could be just one avenue where it looks in order to achieve its aerodynamic goals.