What Is DAS In F1? Is It Legal?

With so much technology, and so many abbreviations used in F1, it’s easy to lose track of what something means. From DRS to FP3, there are lots of abbreviations used in F1, but one that hasn’t been seen since 2020 is DAS.

DAS in F1 stood for Dual Axis Steering, and it was a system used by Mercedes F1 Team in 2020. It allowed the drivers to change the angle of their front wheels while driving by pushing or pulling their steering wheel, helping with stability and tire warmup. DAS was banned for the 2021 F1 season.

That is part of the nature of F1’s constantly evolving rules. Some piece of technology can suddenly appear on a car, only for it to be banned shortly after. Below, we go through what DAS in F1 actually was in more detail, and discuss why it was banned from the sport.

What Is DAS In F1?

Dual-Axis Steering, which was then abbreviated to DAS, was created by the Mercedes Formula 1 team, and it certainly made some waves when it appeared on their 2020 car. DAS was a moving steering system that suddenly emerged during testing. It was capable of changing the alignment of the front wheels, which is referred to as the toe, by simply pushing or pulling on the steering column.

It may sound like a small thing, but by being able to adjust this, it would lead to tires being able to warm more evenly throughout a lap. If the tires are warmed more evenly, it means greater grip for the driver and, as a result, potentially shorter lap times. This was something completely new to F1 cars. However, the FIA were not entirely happy with it, and banned it for 2021.

When Was DAS Used In F1?

DAS was used in F1 only by Mercedes back in 2020. The FIA banned it for the 2021 season, and it hasn’t made an appearance since. DAS was one of many technological innovations in F1’s history that ended up being banned after a short period of use.

However, it’s clear that Mercedes had spent a fair amount of time working on its development. Innovations like these require extensive research before they make their way onto the car.

Teams need to determine if it benefits the car enough to warrant other changes being made to accommodate the technology. If it makes no noticeable difference, then the technology is scrapped. But Mercedes clearly felt this was not the case in this instance, so the banning of the technology meant they only got a year out of all of their hard work creating it.

How DAS Worked In F1

DAS worked by allowing the drivers to alter the toe of the front wheels by pushing and pulling on the steering wheel in the car. This would change the angle of the front tires, allowing the car to have less toe on the straights and more toe in the corners, to suit the driver’s preferences.

By pushing or pulling on the steering column, the driver could subtly change the alignment of the front wheels. Even small changes in how a car enters or exits a corner can make a huge difference over the duration of a single lap, and DAS allowed the drivers to tweak the angle at which the front wheels point outwards.

Changing The Toe

On the straights, Formula 1 drivers would prefer to have no toe on the front wheels. This means the wheels would point forwards, not even slightly to the sides. This minimizes ‘scrub’ which is essentially what happens when parts of the tires aren’t pointing in the direction in which they’re traveling. Over time, this causes wear on the tires, but it also hinders the car’s straight-line speed.

The tradeoff of having slight outward toe of around 1 degree on the front wheels is worth it though, as pointing the front tires slightly outwards means the car is easier to turn into the corner and offers better handling. The inside tire always takes a tighter line in the corners, so having the tire already pointing slightly in the corner’s direction means the car easily takes this tighter line.

Because the front tires are pointing slightly outwards, the car is slightly less stable than it could be on the straights, but in F1 it’s the in corners that time is really made up. This means it’s well worth having a bit of outward toe on the front tires. However, DAS allowed the drivers to ‘straighten out’ the front wheels while on the straights, essentially giving them the best of both worlds.

How DAS Affected Tire Wear

But changing the toe on the front wheels doesn’t just affect the handling of the car. When the tires are pointing slightly out from the center of the car, called negative toe (what they want in the corners), the insides of the tires ‘scrub’ more across the track surface, so the inside of the tires get hotter than the outsides (inside here meaning the part of the tire closer to the car).

With positive toe, when the fronts of the tires point in towards the center of the car, the outsides of the tires scrub more across the track, causing them to heat up more than the parts of the tires closer to the car. This creates an imbalance of tire temperatures, causing different parts of the tires to wear at different rates – not good.

Being able to control the toe of the front tires therefore allowed the drivers to also have more control over the front tire temperatures, on particular parts of the tires as well. This helped deal with tire wear in a more balanced fashion across the tire’s surface, but it also allowed the driver to add heat to the tires when required.

Heating The Tires

On an out lap for example, or behind a safety car waiting for the race to get going again, a driver needs to get heat into their tires to prepare them for their flying lap, or to prepare to safely go racing. F1 tires work within an ideal operating temperature window, meaning they need to be hot enough to provide maximum grip, but not so hot that they overheat.

F1 drivers normally weave or zig zag across the track on an out lap or behind a safety car to build heat in their tires, as they’re cold when the first come out of the garage and when going slower behind a safety car. By allowing the Mercedes drivers to add heat into their front tires without as much weaving required, they could heat the tires faster and without causing excess wear.

By simply controlling tires and how they are worn, teams can run longer on their tire setup, and that changes strategy. Even changing things by several laps will make a noticeable difference, as it opens up a wider window of when cars need to come into the pits. And in qualifying, or behind a safety car, DAS allowed the Mercedes drivers to heat up their tires faster and more uniformly.

Is DAS Allowed In F1?

DAS is not allowed in F1. DAS was banned for the 2021 season, but the Mercedes drivers were allowed to continue using it for the duration of the 2020 season. They were the only team to use DAS.

There was some confusion due to delays in bringing forward certain technical rule changes throughout 2021 and into 2022. However, the FIA eventually declared that the technology would not be allowed moving forward, with a ban starting for the 2021 season.

Why Was DAS Banned In F1?

DAS was banned in F1 due to the high cost of development of the system. F1 is always looking at ways to keep costs down, and to create more of a level playing field for all the teams, so they banned DAS as they deemed it would add too much additional cost.

Final Thoughts

DAS in F1 refers to Dual-Axis Steering, and it was technology that made its debut on the Mercedes cars in 2020. However, it was a short-lived concept, as it was then banned for 2021 before other teams could produce their own versions of DAS.