2026 Aerodynamic & Chassis Regulations

[Moctecus]

What is this latest info, and where is it coming from?

There were stories a while back that they would still need around 100kg during the race, but there is no firm word on that.

70 kg was the target stated back in 2022 [source].
Pat Symonds told AMuS in July that a front MGU would have allowed them to achieve it [source]. AMuS then added, presumably but not confirmed to be coming from Symonds as well, that 100 kg tanks would be required instead.
The most recent information that I am aware of comes from Nikolas Tombazis talking to Motorsport.com in September [source]:

Q: Today, the fuel tank of an F1 car has a maximum capacity of 110 kg of fuel, with the 2026 cars with 50 per cent electric charge how much can be saved?
A: "I imagine a 15% reduction.

Q: We are therefore talking about a tank of around 90 kg, but wasn't there any discussion about reaching up to 75 kg?
A: “It has been talked about, but F1 must not become an economy run where the race pace is dictated by an engineer with consumption strategies. We want the driver to be challenged to the maximum of his capabilities: overtaking must be done on the track after a braking battle and not as a result of an engine strategy."

Q: Will the availability of a little more petrol than would be necessary help to enable hard-fought Grands Prix?
A:“It's exactly what we want, so I will understand the choice of a tank that will have a capacity of around 90 kg”.

[wuzak]

Since hybrid tech is the only option, 2026 PU rules are far better in every way than 2014 rules.

If they 2026 PU rules are better than the 2014-2025 PU rules "in every way" then there would be no issue in delaying the 2026 chassis rules a year or two, and running the 2026 PU in the current generation chassis?

A complaint about the MGUH was that it was too complicated.

To complicated to match with the turbo, or the energy management was too complicated?

The 2026 PUs are loking to be even more complicated energy management wise.

And each rules revision seems to make the energy managemnt problem more complicated.

[wuzak]

70 kg was the target stated back in 2022 [source].
Pat Symonds told AMuS in July that a front MGU would have allowed them to achieve it [source]. AMuS then added, presumably but not confirmed to be coming from Symonds as well, that 100 kg tanks would be required instead.

IMO, a front MGU would have allowed the reduced fuel load only if the front MGU was not allowed to deploy.

That is, energy recovery is done at a higher power level than deployment.

It also has to be considered the fuel energy density.

The fuel flow rate has been reduced to 3000MJ/h from 100kg/h. The 100kg/h was with fuel at ~45MJ/kg, but the 2026 rules specify fuel must be between 38MJ/kg and 41MJ/kg.

Assuming that the fuel energy was reduced to 3000MJ, the fuel mass would be between 73.2kg and 78.9kg, noyt including any that would need to be burned to generate electricity.

70kg of fuel with 38MJ/kg fuel would be very much an economy run!
It would be of the order of 41% - 46% less energy (allowed) than now.

[Cs98]

There were claims that the cars would still use 100kg of fuel for the race, but I doubt that will be the case.

I also doubt that the race fuel will be 30% lower. They are going to have to burn extra fuel to generate the energy for the battery.

The 10% less fuel/11% more time was just an example.

Also, the weight of the car and the drag of the car could be achieved with the current PU.

The 2026 PU is no lighter than the current PU.

The latest info reiterates 70kg of fuel is the target limit, right now it's 110kg but as far as I know on most races cars are fuelled to around 100kg, which is why I said 30%. This is huge and is possible due to introduction of such high powered MGU and the increase in energy store capacity per lap.

Fuel burning on straights or whenever is optimal will be done when the ICE is running in the zone of highest efficiency. Compared to ICE, electric motors can accelerate with 2-3 times higher efficiency (and typically more torque) and this is where all this fuel will be saved.

The only thing missing from these rules are front wheel MGUs (or just GUs) and they will come at some point.

That is not the "latest info", reports have been around for over half a year that it will have to increase to 90-100kg to facilitate fuel burning.

[mzso]

Agreed on front wheel MGUK, that's a given, but as far as I remember teams refused this at the start because it would be too big of a change with everything else changing...

And the FIA should have just put it in anyway. If a team wants to take a punt on a FW-MGUK then let them. If it works, they get the benefit until others catch up.

Part of the problem is the teams are too involved in writing the rules sometimes.

You mean all the time. I don't remember a rule change that wasn't twisted, corrupted, compromised before it was introduced, typically with a delay.
Even the anti-bouncing measures for last year were compromised. Even though the FIA could have unilaterally pushed it through on safety grounds.

[SealTheRealDeal]

Turbo lag has been mentioned as something that can make the cars exciting to watch, but it could be several seconds before the turbo comes on boost. The current units would be around 5-10s if not for the MGUH.

Can the manufacturers just incorporate anti-lag into their engine maps or is that prevented by the regs?

[astracrazy]

https://www.youtube.com/watch?v=N9c_fV7qLzE

"Show me indycar making a 230+ turn without the need for banking....."

You then proceed to show me an Indycar taking turns with banking.

So I take it you agree then or?

Sorry, without my glasses banking and braking look the same

It's ok I was just thinking huh lol

[Vanja #66]

as written this is dangerous nonsense

road or track there is no electric motor that works with a zero-weight zero-bulk zero-cost 100% efficient electricity supply
there is no such supply
like the ICE the EM needs a supply of (electric) fuel

the (present) F1 ICE is hobbled by constrained fuelling and the EM rewarded with unconstrained fueling
though F1 (GPs) for the previous 100 years had unconstrained fueling

Who says anything about 100% efficiency? EM can run along the max-torque curve at very high efficiency values and power electronics also has a very high efficiency, reducing numbers bellow by only 4-5%.



On the other hand, petrol engine is not bad at max-torque curve, but I don't see even these ultra-efficient F1 engines running along the max-torque curve at more than 40-45% efficiency depending on the RPM. That's the "2-3 times more efficient acceleration"

***

Will reply later this evening to both your posts

[wuzak]

Turbo lag has been mentioned as something that can make the cars exciting to watch, but it could be several seconds before the turbo comes on boost. The current units would be around 5-10s if not for the MGUH.

Can the manufacturers just incorporate anti-lag into their engine maps or is that prevented by the regs?

Anti-lag uses fuel which is restricted in current F1, and is only allowed to be injected into the combustion chamber by direct injection.

[AR3-GP]

Turbo lag has been mentioned as something that can make the cars exciting to watch, but it could be several seconds before the turbo comes on boost. The current units would be around 5-10s if not for the MGUH.

Can the manufacturers just incorporate anti-lag into their engine maps or is that prevented by the regs?

Anti-lag uses fuel which is restricted in current F1, and is only allowed to be injected into the combustion chamber by direct injection.

It's true that anti-lag requires fuel but fuel spent to maximize acceleration at the beginning of the straight is more valuable than fuel spent at the end of the straight.

With that said, I do not know if anti-lag is permitted in the regulations. The current F1 cars do make strange noises off throttle however...Especially apparent for Honda and Mercedes.

[Vanja #66]

What is this latest info, and where is it coming from?

I've seen the updated latest info from Moctecus' post today, I've unfortunately missed this info from Tombazis of the fuel limit decrease most likely "stopping" at 90kg. Not a great step as 70kg would be, but 18% is not bad at all. 44% less fuel than 2013 is still pretty stunning.

The energy storage capacity remains the same - 4MJ.

You probably mean the allowable energy recovery per lap, and, therefore, the deployment.

Actually I meant what I said, teams can store that much, just not at the same time during the lap Semantics, of course

They have also reduced the speed at which maximum MGUK power can be used in normal mode (290km/h, down from 300km/h) reduced MGUK power from 150kW above 340km/h to 0kW above 345km/h.

This all suggest to me that there is a lack of opportunity to recovery energy, and that they needed to reduce power output so as not to use it too quickly.

The whole 50/50 power split isn't really true if the MGUK has only half its maximum power at 325km/h.

I don't see this as fundamental, these are tiny corrections based on latest simulation and performance modelling data. Acceleration is where you want to use MGU as much as possible in any case, to save fuel for a fairly steady-state top speed regime where you can use ICE in a near-optimal point where it powers the car and charges the battery.

The MGUK will certainly offset the ICE's turbo lag from slow corners.

I presume ICE efficiency will be well down when it is suffering from turbo lag.

Turbo lag has been mentioned as something that can make the cars exciting to watch, but it could be several seconds before the turbo comes on boost. The current units would be around 5-10s if not for the MGUH.

Indeed, I think turbo lag will be completely covered with MGU and ICE will likely be kept at a fairly high RPM range with as lean as possible mixture. Like I said, from an engineering and tactical/strategical POV these 50/50 hybrids will be a whole new range of options and opportunities.

If they 2026 PU rules are better than the 2014-2025 PU rules "in every way" then there would be no issue in delaying the 2026 chassis rules a year or two, and running the 2026 PU in the current generation chassis?

It would be possible, but it's the right thing to introduce the full package and set it as the baseline for future improvements of technical regulations. And honestly, it's a decent baseline. This discussion started with active aero and that bit is quite an important aspect of 2026 chassis rules.

Just a brief digression, 2009 chassis rule change came as an "answer" to overtaking problems. It was such a good change and it required introducing DRS full 2 years later. Minor chassis rules changes aside, 2017 were the next big change and it was such a stupid move with Ecclestone wanting to make cars faster. Almost like "well, racing is shot in any case, might as well make cars faster and more physically exhausting to drive" which was peak stupidity. 2019 changes were never going to work as good as new FOM hoped, so we finally got 2022 ground effect rules.

Now, 3 years into the rule set, new findings have surfaced on how to further reduce the impact of aero losses when following another car and all teams agreed it's a good thing to make substantial changes ASAP. Smaller and lighter cars, less dependant on aero, aero becoming more robust in any case and finally becoming active, more fuel efficient and PU rules more relevant to road car tech. Are these changes as big as they could have been? Maybe not. Will they be an improvement on the critical points highlighted by everyone? Undoubtedly.

A complaint about the MGUH was that it was too complicated.

To complicated to match with the turbo, or the energy management was too complicated?

No, the technology itself is very complex and sensitive from manufacturing POV. You have 120k RPM turbo subjected to extensive thermal loads. Fine, high RPM turbos have been built for decades. EMs, not so much. Energy management is a non-issue as fas as I understand, but coupling a high-speed EM in a very hot environment is a big challenge. Tolerances are crazy, thermal management is crazy, vibration management is crazy. Parts are very expensive to manufacture and require very special and expensive machines to do so. Road car technology went in another direction since 2014 and such units never became road-relevant even if many attempts to do so have been made. It's simply too expensive to manufacture purely from mechanical POV and ultimately yields very small improvements for road cars, even high-performance specimens.

The 2026 PUs are loking to be even more complicated energy management wise.

And each rules revision seems to make the energy managemnt problem more complicated.

Energy management is solved with software. All the sensors needed to monitor parameters and stay within rules are already there. You can change parameters or write several new pieces of code and test them with simulation in a snap. Simulations give a hint which directions are most promising and those move to test benches and the best solutions get to the car itself. It's an engineering challenge, no F1 team runs away from that.

[Tommy Cookers]

Who says anything about 100% efficiency? EM can run along the max-torque curve at very high efficiency values and power electronics also has a very high efficiency, reducing numbers bellow by only 4-5%.
On the other hand, petrol engine is not bad at max-torque curve, but I don't see even these ultra-efficient F1 engines running along the max-torque curve at more than 40-45% efficiency depending on the RPM. That's the "2-3 times more efficient acceleration"

simply ....
does the hybrid-recovered energy exceed the part of the ICE energy used to drive & brake & DF the the hybrid system ?
(the recovery is some fraction of some fraction of braking energy and recovery that has a cost in fuel or laptime)

if the answer isn't a big yes - we have what others have called greenwashing

the electrical energy that has a cost in fuel - its aggregate cost 'fuel & round trip' amounts to 35-40% efficiency

presumably the 'ultra-efficient ICE' will work without the ERS

[wuzak]

What is this latest info, and where is it coming from?

I've seen the updated latest info from Moctecus' post today, I've unfortunately missed this info from Tombazis of the fuel limit decrease most likely "stopping" at 90kg. Not a great step as 70kg would be, but 18% is not bad at all. 44% less fuel than 2013 is still pretty stunning.

With the lower drag and slower expected lap times from the 2026 chassis, I'm sure the current PU could manage a race on 90kg of fuel, or less.

The energy storage capacity remains the same - 4MJ.

You probably mean the allowable energy recovery per lap, and, therefore, the deployment.

Actually I meant what I said, teams can store that much, just not at the same time during the lap Semantics, of course

Technically the current rules allow for unlimited "storage" over a lap.

The energy in the battery going to and from the MGUK, but the going to and from the MGUH is not.

[wuzak]

They have also reduced the speed at which maximum MGUK power can be used in normal mode (290km/h, down from 300km/h) reduced MGUK power from 150kW above 340km/h to 0kW above 345km/h.

This all suggest to me that there is a lack of opportunity to recovery energy, and that they needed to reduce power output so as not to use it too quickly.

The whole 50/50 power split isn't really true if the MGUK has only half its maximum power at 325km/h.

I don't see this as fundamental, these are tiny corrections based on latest simulation and performance modelling data. Acceleration is where you want to use MGU as much as possible in any case, to save fuel for a fairly steady-state top speed regime where you can use ICE in a near-optimal point where it powers the car and charges the battery.

If they just used the power for a few seconds of acceleration then thy could probably use a smaller battery, saving some more weight.

They could have had the MGUK reduce to 0 by 200km/h, or even 300km/h.

Then they woudln't need such a large amount of recovery requiring the burning of fuel.

The MGUK will certainly offset the ICE's turbo lag from slow corners.

I presume ICE efficiency will be well down when it is suffering from turbo lag.

Turbo lag has been mentioned as something that can make the cars exciting to watch, but it could be several seconds before the turbo comes on boost. The current units would be around 5-10s if not for the MGUH.

Indeed, I think turbo lag will be completely covered with MGU and ICE will likely be kept at a fairly high RPM range with as lean as possible mixture. Like I said, from an engineering and tactical/strategical POV these 50/50 hybrids will be a whole new range of options and opportunities.

Well, if nothing else, it should see the end of the dreaded DRS overtaking system.

All should be allowed to run the override mode when they want. It is, of course, dependent on the amount of energy stored in the battery and the limit to energy recovery.

I think the FIA should publish their simulations so that we have an idea of what to expect when the 2026 season starts.

Otherwise the racing might come as a rude shock.

[wuzak]

If they 2026 PU rules are better than the 2014-2025 PU rules "in every way" then there would be no issue in delaying the 2026 chassis rules a year or two, and running the 2026 PU in the current generation chassis?

It would be possible, but it's the right thing to introduce the full package and set it as the baseline for future improvements of technical regulations. And honestly, it's a decent baseline. This discussion started with active aero and that bit is quite an important aspect of 2026 chassis rules.

My point is that the 2026 PU does not bring and advantages to its weight or size.

Cooling from the ICE will go down, but cooling for the battery, electronics and MGU will go up - no sure if one would outweigh the other.

The 2026 regulations could easily have been written around the current PUs.

But the 2026 PU needs the 2026 chassis rules to have any chance of working and giving expected F1 performance levels.

A complaint about the MGUH was that it was too complicated.

To complicated to match with the turbo, or the energy management was too complicated?

No, the technology itself is very complex and sensitive from manufacturing POV. You have 120k RPM turbo subjected to extensive thermal loads. Fine, high RPM turbos have been built for decades. EMs, not so much. Energy management is a non-issue as fas as I understand, but coupling a high-speed EM in a very hot environment is a big challenge. Tolerances are crazy, thermal management is crazy, vibration management is crazy. Parts are very expensive to manufacture and require very special and expensive machines to do so. Road car technology went in another direction since 2014 and such units never became road-relevant even if many attempts to do so have been made. It's simply too expensive to manufacture purely from mechanical POV and ultimately yields very small improvements for road cars, even high-performance specimens.

The reason why there is no MGUH in the 2026 PU rules is that Audi/Porsche did not want to develop such a system, as the existing manufacturers have much more experience with the technology.

Also, the 2026 PU rules are closer to the LMP1 regulations from 10 years ago, with which Audi and Porsche competed at Le Mans.

There are not many, if any, road cars with 50/50 hybrid power split.

And road cars tend not to run at full throttle 60-80% of the time.