Why Red Bull's F1 teams took opposing approaches with 2021 designs

Red Bull felt that spending development tokens on a new gearbox casing would offer them the most bang for their buck, whilst AlphaTauri, which could have upgraded to the same arrangement used by Red Bull in 2020 without spending any tokens, opted to upgrade its front end instead.

To better understand AlphaTauri's situation, let's take a look at their gearbox casing, crash structure, suspension and brake arrangement from underneath, courtesy of Giorgio Piola's latest illustration.

The AT01 and 02's suspension layout follows tradition in respect of the wishbone design, with the forward arm making up the triangulation.

Encased within the much larger fairing behind this are the rear leg of the wishbone, the track rod and the driveshaft, as the team looks to get the best from an aerodynamic point of view.

AlphaTauri AT02 suspension

Photo by: Giorgio Piola

Had it made the switch to Red Bull's 2020 arrangement, it would have adopted a layout that split up the lower and rearward elements.

But, as we know from Red Bull's 2020 campaign, the team had to fight an imbalance, one perhaps created by this arrangement. So AlphaTauri chose not to hamper its own progress and stuck with its 2020 gearbox casing and suspension layout.

From the Red Bull perspective, it's fair to say that the RB16 had a few issues that the team had to iron out during 2020, not least an obvious instability that caught the drivers out on a few occasions during pre-season testing.

Aside from this quirky rear end behaviour and perhaps even inexplicably linked to it, the team was also fighting a correlation issue.

This happens when a team's simulation tools do not accurately represent what's occurring in the real world. It requires a new focus on rectifying the situation whilst also continuing the search for performance.

This can often be at odds with the current development cycle too, as parts destined for the car will no longer be considered to offer the level of performance that was first indicated, requiring the team to either amend them to suit or ditch that development path entirely.

For Red Bull this meant a series of back-to-back tests during the first few races of the season, with data collected from both cars fed back into the loop. This is, of course, time consuming and takes away valuable set-up time for the race at hand. However, the value in dealing with the issue swiftly pays for itself.

As a consequence, Red Bull quickly discovered that a new front wing and nose development introduced at the first race of the season wasn't giving the expected performance advantage and retired the solution.

However, it did have a revival for the Abu Dhabi Grand Prix, for whatever reason, on Max Verstappen's car before once again being condemned to the parts bin (the narrow front wing pillar arrangement, inset, was ditched by Red Bull).

Red Bull RB16 nose specifications

Photo by: Giorgio Piola

In dealing with these issues early in the RB16's development cycle, the team perhaps inadvertently won some headroom when the homologation and token system was introduced for 2022.

With the front end having been overhauled, the team decided that it would be best served to spend its tokens at the rear of the car instead, with gains to be found in structural integrity, mechanical flexibility and aerodynamic efficiency, as it made changes to their gearbox casing.

That's to say that the actual gearbox remains unchanged for 2021, as modern F1 gearboxes are of a cartridge design, meaning they can be exchanged without needing to replace the entire casing.

If an accident destroys the casing but the cartridge is intact, the driver doesn't have to face the prospect of a grid penalty as it can be inserted in a new casing.

This modular design can result in a weight saving too when compared with the old designs, as it can be shaped and manufactured differently.

The change in casing coincides with a rethink of the rear suspension layout from Red Bull, which has taken a leaf out of Mercedes book in order to improve the layout and the rear end aerodynamics.

Mercedes W11 rear end

Photo by: Giorgio Piola

It has done this by flipping the lower wishbone and track rod positions around, mounting what would have been the forward leg of the lower wishbone as far back as possible on the gearbox casing.

It was unable to achieve as aggressive a packaging as was/is on the W11/12 though, as Mercedes has the rear leg intersect the crash structure in its arrangement (red arrow), which would have cost Red Bull a development token it simply didn't have at its disposal.

The position changes made by both outfits to its wishbone and track rod has a significant aerodynamic impact.

Firstly, it alters the behaviour of the various flow structures that interact due to the protrusion of the diffuser as it ramps up out of the floor 150mm ahead of the rear wheel centreline.

Secondly, there's a change to the position of the suspension elements at the outboard end relative to the brake duct winglets housed on the fence. This is critical for 2021 given the changes made by the FIA to narrow them in the lower half of the fence.

Thirdly, most of the teams are using a trench in the floor beside the sidepod bodywork to enlarge the coke bottle effect, which will also be affected by the positioning of the suspension members and the driveshaft fairing.

Lastly, the rear suspension element being hung high and as rearward as possible means the airflow can have an impact on the flow out of the diffuser too.

Red Bull RB16B suspension

Photo by: Giorgio Piola

If we look at the make-up of the Red Bull RB16's rear end, we can see how the team has not moved too far away from its 2020 set-up.

However, the track rod is now the forward-most element (highlighted in blue, 5) with the two arms of the lower wishbone placed in series (2 and 3), whilst the driveshaft is housed within the rear fairing (red dotted line).

The elevation of the suspension elements are evident when using the keel as a reference point (1), which allows the aerodynamicists the headroom they require to improve flow around the car's rear end and mitigate some of the losses created by the new regulations.

AlphaTauri AT02 front suspension

Photo by: Giorgio Piola

AlphaTauri's decision to retain its 2020 gearbox casing and rear suspension layout and not take a free upgrade or spend its two development tokens on it was born from the idea that it finds more performance from alterations at the front of the car.

This was also only viable due to the free upgrade route though, as it has switched to the rearwards-mounted steering rack that can also be found on the RB16/RB16B.

All of the teams have tended to move their steering assembly and arms as far and low forward as possible in recent years, generally putting them in line with the lower wishbone.

This is done in order to improve aerodynamic output, with the fairings wrapped around the assemblies designed to work in harmony with one another.

However, Red Bull and AlphaTauri have opted to sacrifice some of this aerodynamic performance to help improve the front end's overall packaging.

To mitigate some of these losses and generally improve the aerodynamic profile of the cars front end, AlphaTauri spent its two tokens on a new nose, switching from the narrow thumb tip style to a wider body design.

This also helped them redesign the cape, as it now adopted the side mounted arrangement found on the Mercedes, which started the trend back in 2017.