If you watched the Turkish Grand Prix or the media circus that ensued afterward, then you have heard a lot about Mercedes’ so-called ‘trick suspension’ that has got everyone talking. Some have even gone so far as to claim that it gave Mercedes almost a second a lap advantage over the Red Bulls in Turkey. Apparently, that is why Valtteri was able to stay comfortably ahead of Red Bull ace Max Verstappen.
While it is true that the Mercedes cars have a unique suspension system that gives them an advantage on the straights, you would do well to ignore the pundits suggesting that such a fancy innovation this late in the season spells doom for Red Bull. But before we get into whether it’s a season-ender for Red Bull or not, let us start by examining what the trick suspension is, how it works and whether or not it is legal for Mercedes to run that system on their 2021 car.
It was never about the engine…
It is no secret that Mercedes was quicker than Red Bull during the Turkish, Russian and Italian Grands Prix. What is a mystery is how they managed to achieve that in a season where they have more often than not come second to the Red Bulls, especially in Qualifying.
There were rumors that the fact that Mercedes introduced a new engine for either of their drivers at every one of those Grands Prix had something to do about it. Christian Horner and Dr. Helmut Marko suggested that Mercedes had achieved higher performance levels with their engine after the recent series of engine changes that have come with several penalties.
Increasing engine power and performance would have been ok in any other season other than this one where in-season engine performance upgrades are prohibited. This measure was undertaken by the FIA and agreed to by all engine manufacturers as a way of helping bring down costs for all teams in response to the Covid-19 pandemic.
Red Bull believed that Mercedes was doing some trickery with the placement of the censors in the intercooler that allowed more cool air to be utilized by the engine than was legal. Red Bull believed this was the reason for the pace Mercedes showed on the straights compared to their rivals. Dr. Helmut Marko said as much in his interview with Auto Motor und Sport;
“The longer they are, the more we lose. From the beginning to the end,” he said.
However, those protests from Red Bull were channeled into a formal complaint to the FIA challenging the legality of the Mercedes power unit. However, this complaint was thrown out by the FIA as the Mercedes power unit was found to be legal. This coincided with the arrival of the Turkish GP, where Red Bull found a new part of the Mercedes car to fuss about, the rear suspension.
What is different about the Mercedes rear suspension?
In simple terms (my apologies to the engineers reading this), the Mercedes rear suspension system allows the car to completely level out on the straight and stall the floor, thus eliminating any downforce. This benefits Mercedes on the straights since by eliminating downforce, the car also eliminates most of the drag created by the rear wing and diffuser. Christian Horner astutely observed this;
“If you look at the rear of their car, you can see that it moves down on the straight,” Horner said.
Formula 1 cars use a combination of springs and pushrods in their rear suspension. This allows the two rear wheels to alternate tension and compression loads as they go through the corners. Furthermore, this suspension system allows the car’s rear to push closer to the ground on the straights as an increase in speed results in a squared increase in downforce. This concept can be easily seen on high-rake cars like the Red Bull and Alfa Tauri.
However, since Mercedes is one of only two cars running the low rake concept this season, they can take it one step further. The Mercedes car is able to almost entirely level out of the straight, eliminating any downforce production on the underside of the car. This, in turn, makes the car much faster on the straights since drag is significantly reduced.
It also doesn’t compromise Mercedes in the corners since they don’t have to run a smaller wing to minimize drag on the straights but then compromise downforce in the high-speed corners. That would explain why Mercedes has had a more prominent rear wing than Red Bull at virtually all the races so far this season.
Is this Mercedes’ silver bullet?
As you probably witnessed at the US Grand Prix this weekend, the answer is no. While the Mercedes trick suspension gives them an advantage on the straights, this advantage is much slimmer on tracks with more high-speed corners than straights like the Circuit of the Americas in Austin.
Mercedes need a lot of long straights to maximize this system, and of the five tracks remaining, only Qatar and possibly Brazil fit that requirement. So unfortunately for Mercedes fans, Red Bull still appears to have the faster car in all conditions.