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After the australia gp something come in my mind. Maybe the complicated thing for the drivers is not to harvest the right amount at the right place, but mostly harvest as much as allowed but not to much to not reach the limit (7MJ, 9MJ,...) before the end of the lap and make the MGUK therefore useless for the last 1 or 2 turns?

AR3-GP wrote: ↑

12 Mar 2026, 13:17

FittingMechanics wrote: ↑

10 Mar 2026, 22:40

Are they not able to put the engine in "no electrical use at all" mode? So they do the formation lap purely on ICE power, surely 400 kW can spin the rears at low speeds?

I believe this is relevant:

BorisTheBlade wrote: ↑

12 Mar 2026, 13:14

It means, that teams are basically allowed to use only the ICE starting full-throttle during these sections. In all other sections they are forced to start with at least 200 KW MGU-K on full-throttle.

MGU-K deployment is forced at full throttle, and then there's a specific ramp down rate (iirc its 50kW/s).

Getting the battery level right is very complex because the tire and brake warmup procedures are done in a way that cannot be predicted and must be done until the target temps are reached.

Very good point regarding the formation lap. And to be honest, I did not connect these dots as I was under the impression that this simply would not apply in formation laps. But if this is not explicitly mentioned,then surely it applies.

michl420 wrote: ↑

12 Mar 2026, 18:35

After the australia gp something come in my mind. Maybe the complicated thing for the drivers is not to harvest the right amount at the right place, but mostly harvest as much as allowed but not to much to not reach the limit (7MJ, 9MJ,...) before the end of the lap and make the MGUK therefore useless for the last 1 or 2 turns?

China might be a very good showcase. There it might be better to store as much energy as you can before the last 3 straights and just sacrifice braking recovery somewhere else to stay inside the limit.

AR3-GP wrote: ↑

12 Mar 2026, 13:17

FittingMechanics wrote: ↑

10 Mar 2026, 22:40

Are they not able to put the engine in "no electrical use at all" mode? So they do the formation lap purely on ICE power, surely 400 kW can spin the rears at low speeds?

I believe this is relevant:

BorisTheBlade wrote: ↑

12 Mar 2026, 13:14

It means, that teams are basically allowed to use only the ICE starting full-throttle during these sections. In all other sections they are forced to start with at least 200 KW MGU-K on full-throttle.

MGU-K deployment is forced at full throttle, and then there's a specific ramp down rate (iirc its 50kW/s).

Getting the battery level right is very complex because the tire and brake warmup procedures are done in a way that cannot be predicted and must be done until the target temps are reached.

Hi, can you elaborate which parts of the rules state the 200 kW power limit? I'm trying to model that and my deployment is not quite close to reality, but I am not implementing that rule yet so it must be the key. Also what are the power limited pending periods and how they change the mgu-k behavior?

EDIT: Ok I read the China thread it makes sense now.

wuzak wrote: ↑

09 Mar 2026, 15:55

In Australia they were super-clipping and/or lift-and coasting for at least 10s per lap. Accounting for around half the allowed energy recovery.

If deployment was reduced to a maximum of 4.0 MJ per lap, would there still be any benefit to recovering the permitted 8.0-9.0 MJ per lap?

JordanMugen wrote: ↑

14 Mar 2026, 15:28

wuzak wrote: ↑

09 Mar 2026, 15:55

In Australia they were super-clipping and/or lift-and coasting for at least 10s per lap. Accounting for around half the allowed energy recovery.

If deployment was reduced to a maximum of 4.0 MJ per lap, would there still be any benefit to recovering the permitted 8.0-9.0 MJ per lap?

There wouldn't be any point to have the 8-9 MJ per lap limit.

If you could only use 4MJ, and store 4MJ, you could only recover 8MJ every second lap.

wuzak wrote: ↑

15 Mar 2026, 06:05

JordanMugen wrote: ↑

14 Mar 2026, 15:28

wuzak wrote: ↑

09 Mar 2026, 15:55

In Australia they were super-clipping and/or lift-and coasting for at least 10s per lap. Accounting for around half the allowed energy recovery.

If deployment was reduced to a maximum of 4.0 MJ per lap, would there still be any benefit to recovering the permitted 8.0-9.0 MJ per lap?

There wouldn't be any point to have the 8-9 MJ per lap limit.

If you could only use 4MJ, and store 4MJ, you could only recover 8MJ every second lap.

It would help with tactical things though, no? No running out of battery power down to zero, as there is always reserve.

So even if pointless to only change one aspect, doing the in-season rule change only to the deployment MJ number would still be OK? It is not necessary the change the harvesting MJ number.

Edit -- MJ/lap numbers are not even a rule as such, it is something FIA announces per Grand Prix as event notes (?), so the FIA can trial a 4 MJ deployment limit already in Japanese Grand Prix (if the FIA wants) to see what effect it has?

JordanMugen wrote: ↑

15 Mar 2026, 11:05

wuzak wrote: ↑

15 Mar 2026, 06:05

JordanMugen wrote: ↑

14 Mar 2026, 15:28

If deployment was reduced to a maximum of 4.0 MJ per lap, would there still be any benefit to recovering the permitted 8.0-9.0 MJ per lap?

There wouldn't be any point to have the 8-9 MJ per lap limit.

If you could only use 4MJ, and store 4MJ, you could only recover 8MJ every second lap.

It would help with tactical things though, no? No running out of battery power down to zero, as there is always reserve.

So even if pointless to only change one aspect, doing the in-season rule change only to the deployment MJ number would still be OK? It is not necessary the change the harvesting MJ number.

Edit -- MJ/lap numbers are not even a rule as such, it is something FIA announces per Grand Prix as event notes (?), so the FIA can trial a 4 MJ deployment limit already in Japanese Grand Prix (if the FIA wants) to see what effect it has?

C5.2.10 Recharge, as measured at the CU-K HV DC Bus, must not exceed
a limit of 8.5MJ in each lap, subject to the following additional conditions:
i. This limit may be reduced to 8MJ at Competitions where the FIA determines that the maximum possible energy harvested per lap attributable under braking and in partial load is no more than 8MJ.
ii. This limit may be further reduced to no less than 5MJ for Sprint Qualifying and Qualifying sessions at Competitions where the FIA determines that the harvesting strategies required to achieve the above limit are excessive, subject to the conditions specified in Article B7.2.
iii. Up to 0.5MJ of additional energy may be harvested in each lap subject to the conditions specified in Article B7.2.
The vehicle fundamentals used to determine the above limits will be provided in the document FIAF1-DOC-034.

I noticed something with the rear facing red lights in the wing endplates.

We are used to them flasing when harvest kicks in, that is still there.

But I noticed that often, not always, they would blink red a single time, at the beginning of the straights or even at the end of the corner just before a straight.
Is that to signal that electric deplowment has started? And why would the guy behind need to know that you will accelerate faster?

P.S. attempting to fix the thread name now that we have more data and less spculation.

hollus wrote: ↑

15 Mar 2026, 17:00

I noticed something with the rear facing red lights in the wing endplates.

We are used to them flasing when harvest kicks in, that is still there.

But I noticed that often, not always, they would blink red a single time, at the beginning of the straights or even at the end of the corner just before a straight.
Is that to signal that electric deplowment has started? And why would the guy behind need to know that you will accelerate faster?

P.S. attempting to fix the thread name now that we have more data and less spculation.

I saw, and wondered the same.

Likewise unable to attach definitive reason to it, but thought was toward finishing "harvesting" with at that point full forward torque deployed ? Possibly as the driver ultimately hit full power request in throttle travel.

Perhaps to give some warning to following driver of impending rear ending potential, but couldn't see enough incident to give reasonable correlated comment.

wuzak wrote: ↑

15 Mar 2026, 15:50

C5.2.10 Recharge, as measured at the CU-K HV DC Bus, must not exceed
...
ii. This limit may be further reduced to no less than 5MJ for Sprint Qualifying and Qualifying sessions at Competitions where the FIA determines that the harvesting strategies required to achieve the above limit are excessive, subject to the conditions specified in Article B7.2.

Thank you!

Does the FIA have a provision to reduce deployment MJ/lap in qualifying as well?

Would FIA universally mandating 5 MJ/lap maximum harvesting in qualifying be enough to reduce superclipping and corner sacrificing in qualifying?

Edit -- I see that there is no limit on deployment MJ/lap at all (I think?)

So since the 5 MJ/lap qualifying provision is there, could be that trialled in Japan with a view that a maximum 5 MJ/lap harvesting be mandated in all 2026 qualifyings, since the FIA has the authority to declare any qualifying superclipping as "excessive"!

It seems the FIA erred (in giving themselves room to fix the regulations in-season) by not allowing themselves to similarly reduce race harvesting to 5 MJ/lap (or indeed less)... I wonder why they would have boxed themselves in like that for?

C5.2.7 The absolute electrical DC power of the ERS-K may not exceed 350kW.

Why didn't the FIA give themselves the authority to reduce this in season at their discretion‽ That seems most unwise given the inevitable push back against excessive electrical power relative to potential to harvest that has duly arrived.

JordanMugen wrote: ↑

15 Mar 2026, 19:19

wuzak wrote: ↑

15 Mar 2026, 15:50

C5.2.10 Recharge, as measured at the CU-K HV DC Bus, must not exceed
...
ii. This limit may be further reduced to no less than 5MJ for Sprint Qualifying and Qualifying sessions at Competitions where the FIA determines that the harvesting strategies required to achieve the above limit are excessive, subject to the conditions specified in Article B7.2.

...

C5.2.7 The absolute electrical DC power of the ERS-K may not exceed 350kW.

Why didn't the FIA give themselves the authority to reduce this in season at their discretion‽ That seems most unwise given the inevitable push back against excessive electrical power relative to potential to harvest that has duly arrived.

They actually have this authority:

B7.2.1 b. No less than four (4) weeks prior to the start of a Competition, the FIA will provide all
Competitors with the following information and limitations applicable to the Competition,
which must be respected at all times during the Competition:

i. Subject to Article C5.2.8i, and only if deemed necessary by the FIA for the sole purpose of
ensuring the maximum speed of the F1 Car remains compatible with the design and
construction of the relevant circuit, any adjustment(s) of the maximum electrical DC
power of the ERS-K, as a function of F1 Car speed, that may be used to propel the F1 Car
when Overtake Mode is not active.

Edit: To be fair, it will be hard to argue that the reduction in MGU-K power is to enure the maximum speed remains compatible with the design and construction of the relevant circuit, so they might not be able to use that.

karana wrote: ↑

15 Mar 2026, 23:03

JordanMugen wrote: ↑

15 Mar 2026, 19:19

wuzak wrote: ↑

15 Mar 2026, 15:50

C5.2.10 Recharge, as measured at the CU-K HV DC Bus, must not exceed
...
ii. This limit may be further reduced to no less than 5MJ for Sprint Qualifying and Qualifying sessions at Competitions where the FIA determines that the harvesting strategies required to achieve the above limit are excessive, subject to the conditions specified in Article B7.2.

...

C5.2.7 The absolute electrical DC power of the ERS-K may not exceed 350kW.

Why didn't the FIA give themselves the authority to reduce this in season at their discretion‽ That seems most unwise given the inevitable push back against excessive electrical power relative to potential to harvest that has duly arrived.

They actually have this authority:

B7.2.1 b. No less than four (4) weeks prior to the start of a Competition, the FIA will provide all
Competitors with the following information and limitations applicable to the Competition,
which must be respected at all times during the Competition:

i. Subject to Article C5.2.8i, and only if deemed necessary by the FIA for the sole purpose of
ensuring the maximum speed of the F1 Car remains compatible with the design and
construction of the relevant circuit, any adjustment(s) of the maximum electrical DC
power of the ERS-K, as a function of F1 Car speed, that may be used to propel the F1 Car
when Overtake Mode is not active.

Edit: To be fair, it will be hard to argue that the reduction in MGU-K power is to enure the maximum speed remains compatible with the design and construction of the relevant circuit, so they might not be able to use that.

It might be relevent for Monaco.

Does anyone think that the 130°C test would be effective against anything? How hot is the cylinder wall expected to be? I would imagine several hundred °C at least.

wuzak wrote: ↑

15 Mar 2026, 15:50

ii. This limit may be further reduced to no less than 5MJ for Sprint Qualifying and Qualifying sessions at Competitions where the FIA determines that the harvesting strategies required to achieve the above limit are excessive, subject to the conditions specified in Article B7.2.

Well, at least they have blanket authority to improve the look of qualifying, if nothing else.

To be fair though, the look of racing right now is lots better than it was before 2022. With the inept following each other throughout the whole race. And the euphemistically calling it "processional".
However we might get back to it in during the year as everyone figures out their deployment strategies.

hollus wrote: ↑

15 Mar 2026, 17:00

But I noticed that often, not always, they would blink red a single time, at the beginning of the straights or even at the end of the corner just before a straight.
Is that to signal that electric deplowment has started? And why would the guy behind need to know that you will accelerate faster?

Couldn't it be opportunistic harvesting until they're grip limited? And/or using the K as RPM limiter?

Ultimately these regs are dancing around a mass-inefficient, volume-inefficient from of energy storage--the Li-ion battery. These regs consist of trying to make them work, forcing every rule about them. Which has left us with convoluted, micro-managed specifications rendering a foreign display on the track.