Why the very narrow side boxes on the Mercedes W13 can be a disadvantage in the 2022 Formula 1 season and what Mercedes is doing about it?
Mercedes needs answers, and urgently. At the sixth race weekend of the 2022 Formula 1 season in Barcelona in Spain, the team wants to put its W13 and its radical concept to the test again before the engineers proceed with the further development of the Silver Arrow. The key question here: stay with the current philosophy or try something completely different?
Barcelona could provide Mercedes with the decisive insights. Because Formula 1 tested on the Circuit de Barcelona-Catalunya before the start of the season, so there is enough comparative data. This shows how much progress Mercedes has made with its W13 since then – and whether the concept is future-proof or not. Because it is becoming more and more evident: The extraordinary vehicle design of the Silver Arrow with its very narrow sidepods could be a disadvantage compared to the competition. Because with the Mercedes, a significantly larger area of the underbody surface is free.
Toto Wolff: The car has to become more predictable
Or as team boss Toto Wolff put it in Miami: “If you walk through the starting grid, you can see that our underbody sticks out much further than on any other car. This means there is a chance of more instability. That’s the big difference in our concept .”
For him and his team, the sixth race of the season is about “finding out how we can use the current car so that it behaves predictably for the drivers,” explains Wolff. And he also says: “The vehicle that we used [at the test] in Barcelona is significantly slower on paper.” In other words, Mercedes has improved technically since then.
The so-called porpoising, the hopping of the vehicle when driving straight ahead, has remained. And the Mercedes W13 continues to suffer massively from the effect , the drivers are shaken up significantly more than their colleagues in other cars. The free-standing underbody could do its part. Although this aerodynamic solution gives the airflow around the vehicle more leeway, the porpoising hits Mercedes harder than its opponents: it starts earlier on the straights and usually hinders Lewis Hamilton and George Russell longer, often right into the braking zone.
Mercedes restricts itself to holding struts
A key factor here may also be the retaining strut, which the World Automobile Federation (FIA) approved after winter testing. This strut connects the chassis and underbody and should at least reduce porpoising, because the underbody is less deformed thanks to the strut.
What is striking about the Mercedes W13 is that the metal strut is significantly longer than that of other teams. The explanation for this is obvious: on Mercedes, the strut is not routed through any superstructures of the car, but stands mostly free (small picture, red arrow) and thus disturbs the air flow on the way to the rear, more than in other vehicles.
And here another disadvantage of the Mercedes design can be seen: Because the side boxes are so narrow, it is not possible for the team to install so-called hidden struts. The compact design of the W13 Silver Arrow doesn’t give that away. Ferrari and Red Bull, on the other hand, use hidden struts to strengthen their underbody, and they do so farther forward on the car than Mercedes. And because these hidden struts are not in the wind, other technical specifications also apply. So while Mercedes works with one long support strut, other teams can use multiple support struts.
Is it worth going back to the original concept?
And so Mercedes has to deal with the question of whether a return to the concept that had been used at the start of winter testing could be an option. Because this original design was rather conventional, similar to the competition.
But: Porpoising also occurred at Mercedes with this. And: With a change back to the original concept, Mercedes would change the side box design, but would still have a very narrow rear end with a lot of exposed underbody surface that would still be in the airflow.
In addition, would the team be able to reconcile the updates used so far with the conversion to the first version of the vehicle, or would these developments have been in vain?
Either way, Mercedes is facing a decision that needs to be made as soon as possible. And it’s not just about the current car, but also about the design direction for the Formula 1 vehicle in the 2023 season. Because this project should also have started at Mercedes by now, based on the first findings from the 2022 season.