2026 Aerodynamic & Chassis Regulations

[vorticism]

https://i.imgur.com/Is2tn5r.jpeg

Good work, timely. There was one more area I was planning to speculate about. Good that you are working at accurate scale. One thing to notice on your illustration is the t-tray area. As mentioned earlier in this thread, the regs were updated to allow an open t-tray with a faired or exposed shock absorber (pre-’22 type) along with the closed type that you depict (’22-onward type). If a team picks the open option, they will need to move some or all of that area’s housed auxiliary components to the sidepods. The cars are getting narrower and shorter, so presumably less open volume in the sidepods, although the cooling needs will reduce (70% of current fuel flow & more electric drive), meaning smaller radiators. From the side view you have, one can also get an idea of how the bigger louver allowance could be implemented.

..."Floor Corner," a square section directly in front of the rear tyre ... 3 x, 4 y, 2 z sections ...

More of a triangle with a notch. It’s a very specific shape with a very specific section allowance count, and it’s placed in a critical area, right next to the diffuser. Extends right up to the edge of it. One has to ask why, and why it was added so late in the game. Countless concepts could be proposed. Qvist on x/twitter has renderings of one option, a multi-element wing, which seems like the most realistic approach. I've been considering other concepts, a few of which are depicted below. Side-washing scoops, a duct (similar in proportions to an S-duct) to redirect a portion of floor overwash to the 2011 era EBD area, arrays of vanes, and a variation on a wing profile. If features are bridged together then these devices can become rather complex leading to sawtooth forms like we see on the current edge wings.




The t-tray (bib) and ‘Floor Corner’ areas are among the most important aero regions of these cars (leading and trailing edges of the floor), and they both got big updates to their regs 6-8 mo. before on-track testing.

In general I think cooling & packaging will see a lot of dev in these regs, as the floor has become much simpler and the car body will presumably be as compact as possible owing to the reduced overall footprint of the cars and the return of flat floor aero concept, if such a correlation to the previous flat floor cars is accurate.

[vorticism]

Qvist delivered on the horizontal bargboard slats. We'll see in a few months if any teams pursued something like this.
https://x.com/Qvist_Designs/status/1958619801389342751

https://i.imgur.com/Is2tn5r.jpeg

... From the side view you have, one can also get an idea of how the bigger louver allowance could be implemented.

I'd be surprised if no one's been investigating this.

Skimming through the 2026 regulations, it seems to have some easter eggs. The biggest one may be the changes to wording of the engine cover & louver aperture allowances. They might provide the main visual differentiator of 2026: large unusual louvers. I haven’t seen anyone pick up on this yet, so here's a guess at one possible permutation: sidepod cannons.

[Blackout]

Great designs, insight and ideas Vorticism, I love that cannon solution, and completely ducted radiators in general : P

It's funny that before every regulation change, many people wish Formula 1 would get rid of the rear wing 'to improve racing', when in fact that would actually make things worse AFAIK, because RW doesn’t just produce DF, it also helps lift a large portion of the dirty air upward and away from the following car. Without it, the turbulent wake would stay lower and concentrated, hitting the following car directly and making things worse.

A propos wake, Racecar engineering and its partners did another interesting CFD study of the aero 2026 rules and in comparison to a 2025 car, and if they are right, then 2026 might achieve the goals that 2022 aimed to achieve (with success at the beginning), and maybe better (before it gets worse again?) .
.

Wake induced performance degradation has long been one of the principal barriers to sustained close racing in Formula 1. The low energy, highly turbulent flow behind a car destabilises the aerodynamic platform of a following vehicle, particularly at the front wing, leading to a cascade of understeer, tyre degradation and lost lap time. The 2026 aero configuration addresses this by re-balancing downforce generation towards the underfloor, making the cars less susceptible to wake interference, and by reducing outwash-inducing elements at the front end. The net result is a wake that dissipates more efficiently, with a reduced impact footprint. Crucially, this means a following car can maintain a more stable aerodynamic balance and retain a higher proportion of its downforce when in pursuit. Precisely what the FIA intended with the regulation overhaul."

A short summary (of the fixed aero part):
- Underfloor (ground-effect) increases. The underfloor share of total DF rises from ~34% to ~46% so more of the load is produced by the high L/D ground effect and less by the exposed wings.
- Front wing importance is reduced. FW contribution falls from ~30% to 23%,
- Front floor recovers more front load. Peak DF levels are comparable to 2025, but the location of peak suction has migrated forward, shifting the aero balance slightly ahead and reducing the dependency on front wing loading to achieve equilibrium, so the cars should become less vulnerable to performance losses in disturbed flow.
- Wake is narrower and higher-energy with a smaller wake cross-section and higher residual total pressure, rather than a large, low-energy turbulent blob

But for the 2026 concept to work, it’s essential that the front section of the floor generates strong suction under all conditions IMO (and the diffuser kick). That was one of the goals of the 2022 regulations — to stop relying solely on large suction areas at each end of the car, and instead add a third one in the centre to mitigate the big balance shifts experienced pre-2022 when running in dirty air. But I’m not sure how the 2026 floor mouth will manage that, given that it’s going to take all the wheels turbulent airflow head-on...

This makes me think of this:
.

A few more areas of interest:

--Sidepods: The sidepod volume overlaps the leading edge of the floor volume. It might be tempting to use the sidepod component body as an extension of the floor, although with concessions to the shaping limits of the sidepod (section & radius limits). It would be unorthodox to locate the lower edge of the sidepod so close to the leading edge of the floor, a treatment not seen since before 2009, so it may be a bad idea. The main advantage I see here would be in powering the FLEDs with a vertically oriented airstream.

and 2022 when several teams (Ferrari, Mclaren, Haas etc) had very forward and super fat sidepod fronts at the bottom and seemed to use them to force feed the floor mouth with less dirty air, like some bargeboards did...

[vorticism]

I should clarify that the Floor Leading Edge Devices are now totally underneath the floor. Those sidepod concepts were referencing an earlier issue of the regs where the FLEDs extended forward and were exposed, looking like a beard trimmer. The sidepod-floor volume interaction is still the same though, so using the sidepod as a forward floor extension should still be an option if advantageous, but the FLEDs won't be so exposed.

A short summary (of the fixed aero part):
- Underfloor (ground-effect) increases. The underfloor share of total DF rises from ~34% to ~46% so more of the load is produced by the high L/D ground effect and less by the exposed wings.
- Front wing importance is reduced. FW contribution falls from ~30% to 23%,

Is this also from the Racecar Engineering article? Their claim is that the 2022 cars only produced 34% of total DF from the floor? I thought it was much more than that.

Regarding wake, I got the impression that the cars were following more closely 2022-2025 than they were prior, but maybe this is subjective. The wake of the '22 era cars may be reduced but if the floors are relatively more sensitive compared to flat raked floors, then it would make sense that the benefit is reduced. Tangent on rake: at COTA this year I noticed on corner exit that some cars (McLaren f.e.) had transient positive rake (nose up) during accel. The '22 era floors using close to 0* static rake are prone to that, teetering about zero during braking & accel, intermittently nose down and nose up. Whether that can be accommodated in '26, we'll see.

[Blackout]

I should clarify that the Floor Leading Edge Devices are now totally underneath the floor. Those sidepod concepts were referencing an earlier issue of the regs where the FLEDs extended forward and were exposed, looking like a beard trimmer. The sidepod-floor volume interaction is still the same though, so using the sidepod as a forward floor extension should still be an option if advantageous, but the FLEDs won't be so exposed.

A short summary (of the fixed aero part):
- Underfloor (ground-effect) increases. The underfloor share of total DF rises from ~34% to ~46% so more of the load is produced by the high L/D ground effect and less by the exposed wings.
- Front wing importance is reduced. FW contribution falls from ~30% to 23%,

Is this also from the Racecar Engineering article? Their claim is that the 2022 cars only produced 34% of total DF from the floor? I thought it was much more than that.

Regarding wake, I got the impression that the cars were following more closely 2022-2025 than they were prior, but maybe this is subjective. The wake of the '22 era cars may be reduced but if the floors are relatively more sensitive compared to flat raked floors, then it would make sense that the benefit is reduced. Tangent on rake: at COTA this year I noticed on corner exit that some cars (McLaren f.e.) had transient positive rake (nose up) during accel. The '22 era floors using close to 0* static rake are prone to that, teetering about zero during braking & accel, intermittently nose down and nose up. Whether that can be accommodated in '26, we'll see.

I thought too.
Yes it's their claim, but they are talking about the 2025 car that they modeled and used for these simulations and comparisons with their 2026 car model.
.

Current projections indicate the combined effect of the regulation changes could result in an overall aerodynamic performance drop of between 15 and 30 per cent. However, further from overall downforce levels, which should be similar for every team, and will undoubtedly increase as teams work to better understand the new platform, we are interested in evaluating how this downforce is generated and distributed. Generating less downforce, but doing it in the same way, wouldn’t bring any significant change to the game, just slower cars. So, the question becomes: is there any real difference in how this downforce is generated? To evaluate this, we configured both the 2025 and 2026 reference models with identical boundary conditions: a ride height of 20 / 60mm (front / rear); four degrees of yaw, and a front aerodynamic balance set at 35 per cent. Furthermore, we set up both cars to have similar downforce levels, so we can evaluate the differences in scenarios as closely as possible.

... so maybe the 2025 car ride height is not optimal, hence the seemingly weak floor

[Tommy Cookers]

A short summary (of the fixed aero part):
- Underfloor (ground-effect) increases. The underfloor share of total DF rises from ~34% to ~46% so more of the load is produced by the high L/D ground effect and less by the exposed wings.
- Front wing importance is reduced. FW contribution falls from ~30% to 23%,

Is this also from the Racecar Engineering article? Their claim is that the 2022 cars only produced 34% of total DF from the floor? I thought it was much more than that.

are people saying that the ground effect gave higher L/D ?

I thought that exposed wings gave higher L/D than did the ground effect
because one of our clever people said so

[karana]

The floor+diffuser produced 50%+ of the total downforce already in 2009 according to Willem Toet https://www.linkedin.com/pulse/what-par ... illem-toet

The claim that ground effect increases also contradicts basically everything we heard about the 2026 cars. We know that they'll be partially flat again. Wasn't this also done to make the cars less reliant on super stiff suspensions?

The 34% number seems so incredibly off that it I honestly doubt there is anything insightful in their analysis.

[vorticism]

To evaluate this, we configured both the 2025 and 2026 reference models with identical boundary conditions: a ride height of 20 / 60mm (front / rear); four degrees of yaw, and a front aerodynamic balance set at 35 per cent.

1* of rake across a 3 m wheelbase.

A short summary (of the fixed aero part):
- Underfloor (ground-effect) increases. The underfloor share of total DF rises from ~34% to ~46% so more of the load is produced by the high L/D ground effect and less by the exposed wings.
- Front wing importance is reduced. FW contribution falls from ~30% to 23%,

Is this also from the Racecar Engineering article? Their claim is that the 2022 cars only produced 34% of total DF from the floor? I thought it was much more than that.

are people saying that the ground effect gave higher L/D ?

I thought that exposed wings gave higher L/D than did the ground effect
because one of our clever people said so

I don’t think so. ‘High’ as in the numerical value of the first part of the ratio. A glider is said to have low drag while having a high L:D ratio (as description of the actual ratio value), and some will say it has a low L:D ratio (as a description of the drag force), depending on how it’s intended. Sort of like with ‘low’ and ‘high’ gears and gear ratios, there can be some colloquialism.

[WardenOfTheNorth]

Have to be careful exactly what I share on this one as it's info through work, but in 11 weeks at least one team will have run their shakedown test....assuming all stays on target.

2 teams so far have them booked, probably more just that the info hasn't been shared yet.