Why F1’s new brake rules have posed a fresh challenge in 2022

One area that has changed significantly, and has caused some early dramas for a number of teams is the brakes.

Teams had built a reliance on the brake assembly for a number of reasons, all of which have been reduced significantly as part of a push to reduce costs and improve the racing.

Firstly, the allowable brake disc diameter has been increased in line with the additional weight that the cars are carrying this season.

This has resulted in the front disc increasing from a maximum of 278mm to between 325mm and 330mm, whilst the rear must now be between 275mm and 280mm.

Furthermore, the FIA has added a clause that the drill holes must be a minimum of 3mm in diameter. This obviously has a bearing on the maximum number of holes that is possible, as well as their layout, in order that the disc's integrity is not compromised.

In preparation for this, Ferrari began experimenting with a new drill hole layout during the closing stages of the 2021 season, as can be seen in the inset (red arrow).

Another aspect of the regulatory overhaul that’s had an impact on the design of the brake assembly is that the airflow must now be rejected from a rearward facing outlet on the inner brake duct fence.

This is partly due to the reintroduction of the wheel covers, which have been designed to infer a specific aerodynamic function.

F1 and the FIA did not want this airflow disrupted by teams being able to vent heat and airflow out the wheel face.

This change in venting technique has led to some teams re-evaluating the position of the caliper, which had invariably been moved in order to improve the route that the airflow took across the front face of the drum. Before this year, the caliper was typically positioned between 6 and 9 o’clock.

Alpine A521 and 522 front brake comparison

Photo by: Uncredited

This gave the aerodynamic department more license to create crossover and bypass ducts, in order that the airflow passing through them could have more of a benefit as it escaped through the forward half of the wheel face.

However, without these aerodynamic tools at their disposal, some teams have opted to return to the more traditional 3 o’clock position in 2022, as seen here when we compare the Alpine A521 & A522 assemblies.

Interestingly, Alpine has also chosen to utilise a row of teardrop-shaped channels in its caliper housing, allowing the heat generated by the disc a pathway through the assembly, and reducing some of the heat soak that might ordinarily be present without them.

The increased diameter of the wheel well, with the wheels having increased from 13” to 18”, also has a bearing on how teams approach the various challenges they face too. The overall size of the brake drum has increased to match there being more room internally as a consequence.

This not only has implications in regards to the movement of airflow into the brake assembly to cool the components, but it also has a bearing on how it and the heat generated within is extracted.

This holds even more importance when we consider how teams used to lean on these interwoven airflow and heat management strategies to help influence tyre temperatures.

Red Bull Racing RB16B front brake duct comparison, Mexican GP

Photo by: Giorgio Piola

Taking the Red Bull RB16B as an example, the team had numerous brake duct solutions at its disposal to trade off aerodynamic assistance, brake cooling and wheel rim heating depending on the prevailing conditions and each driver's preferences.

Red Bull used a paint coating on the bypass section of the drum in order to limit how the heat that was generated within impeded flow through the assembly, and heated the wheel rim and tyre.

However, there were times when the team wanted the heat to be evacuated more quickly and allowed it to mix with the airflow moving through the bypass, thus also having an impact on wheel rim and tyre heating.

Both teams in the Red Bull stable have enclosed their brake discs this season, in order to inhibit the passage of the heat created by them and direct it more quickly out of the rear facing duct on the end fence.

However, whilst Red Bull and AlphaTauri have the same overall design philosophy, their choices have been limited by the design and positioning of other items that make up the brake assembly.

Meanwhile, both teams have made different choices when it comes to the materials involved, in order to help achieve their thermodynamic goals.

McLaren is another of the teams to use this solution but, having had brake problems during the second test, it has been forced to switch materials, junking the carbon fibre arrangement it initially tested and replacing it with a metal version.