Is the current F1 rear wing capable

[maxxer]

Following Alonso's crash and also problems at the circuit in australia with wind.
Is the current F1 wing capable of producing enough downforce for the power which can be unleashed with the current engines.
Or do we have another problem in the series where the rules control too much and we can just as well remove the wing because during a gust of wind the car gets unhandable with this silly "flap" we now have on the back.

[wesley123]

Yes, the current rear wings are capable

[maxxer]

As i see it

The wings were made smaller during the time of the old engines to produce less downforce , but like many rules since this new engine formula were they reconsidered.
Do the rules for the current wing match the output of the current engines , i dont feel so as these rules are the same as when we had the old engines.

[turbof1]

Following Alonso's crash and also problems at the circuit in australia with wind.
Is the current F1 wing capable of producing enough downforce for the power which can be unleashed with the current engines.
Or do we have another problem in the series where the rules control too much and we can just as well remove the wing because during a gust of wind the car gets unhandable with this silly "flap" we now have on the back.

Well, I'm not really sure if we can place this down to the alonso crash, and I certainly do not want to open that debate in this topic.

But concerning the rear wing: the issue is that teams have lost the beam wing, which served as stepping stone between diffuser and rear wing, upwashing the air and aiding in aero stability on the underside of the wing. It made the low pressure flow stay more attached on the rear wing.

That's gone, although max AoA has also been restricted due new chord rules. One can say rear wings now are more prone to stalling. I wouldn't say it doen't produce enough downforce, but the aero stability could certainly be better.

Also, not all the downforce comes from the diffuser; the diffuser and floor generates the brunt of the downforce on higher speeds.

The current engines have a high torque curve, causing wheel spin if the torque overcomes the traction. But traction is given by both mechanical and aerodynamic grip and that is a lot more complex then just down to the rear wing. Therefore I'd certainly not involve Alonso in this.

[maxxer]

Why i point out to Alonso is that the team mentioned the gusts in Barcelona and also in Australia drivers had difficulty controlling the car because of gusts. Which was mentioned during the practice runs.
So loosing the the beam wing is that the reason the cars will be more sensitive to gusts and wind on track.

[Tim.Wright]

The rules would be helping in this regard since they are reducing downforce which means less of the car's performance is sensitive to wind compared to years gone by.

You will always have an imbalance of grip vs power. Reducing rear downforce just means that the driver's now have to be more controlled with the throttle application.

The DRS flap, by the way, has nothing to do with anything in this case.

Bit of a non-discussion really...

[turbof1]

Why i point out to Alonso is that the team mentioned the gusts in Barcelona and also in Australia drivers had difficulty controlling the car because of gusts. Which was mentioned during the practice runs.
So loosing the the beam wing is that the reason the cars will be more sensitive to gusts and wind on track.

Yes, but we are not factoring in what it meant for the diffuser.

I'm probably going to shoot myself into the foot with saying this, I absolutely want to avoid having another topic to have a polemic about the crash, but the speeds were said to be around 210kph (not 150 as first was claimed). At that point the diffuser and floor are producing a lot more downforce then the rear wing. Having the diffuser stalled due wind, which is very possible, is more serious at those speeds then having your rear wing stalled.

We don't know what got stalled by the wind. Was it the rear wing, diffuser or perhaps both? Again, I'm all about discussing this in general terms, but let's avoid tangling this with the specific Alonso case. Mclaren never said what got stalled in the first place.

If you want more rear wing stability, I'd say a combination of rules restricting AoA combined with allowing more elements would seriously help in this regard.

[maxxer]

repeat

[Bazza]

The rules would be helping in this regard since they are reducing downforce which means less of the car's performance is sensitive to wind compared to years gone by.

I don't know about that. Perhaps before, with the double blown diffusers with fries, or the wide rear wings or the ground effects cars, they were so far above and beyond the required grip needed at 200kph+ that the wind didn't have any effect, but now with less rear downforce, they've been dragged into the zone where the wind can have an effect.

Like in 2010 you had 150% of the required downforce, a gust of wind in the worst possible place/time would take that to 140%.

And in 2015 you have 105% of the required downforce, and a bad gust of wind could take you down to 95% and cause a crash

[Just_a_fan]

This sounds like someone who dislikes the current rules looking for "evidence" that they're dangerous and should be changed.

As for the OP's point about the cars now being too powerful for the current rear wing, the McLaren isn't that powerful yet - you'd expect the more powerful Mercedes to be struggling if the original premise was correct.

Nothing to see here, move on.

[Tim.Wright]

I'd look at it a different way. A given velocity of air (Vair) from a disturbance gust will change the downforce by
dFz = 0.5 x rho x Cz x A x Vair^2.
So the lower the Cz (as the regulations are tending towards) then the lower the loss of downforce.

Secondly, the resulting loss of grip depends on the ratio of aero load to weight load as your total grip depends on those two effects superimposed. I.e.

Total_grip = mu x (mass x gravity + Downforce)

As the total downforce is reduced, its contribution sensitivity to the total grip drops too. In other words, changing losing 10% of downforce when your lift/weight ratio is 4:1 means an 8% reduction in grip. Losing 10% of your downforce when your left/weight ratio is 0.5:1 (e.g. a GT car) then its only 3% of grip which is lost.

Long story short, the more you restrict the aero, the less sensitive the cars should become to wind disturbances.

EDIT: To put it in a more concise form - here is the sensitivity of acceleration due to grip due to a variation in airspeed:

dAccel/dAirspeed = (mu x rho x Cz x A x Airspeed / mass)

If you reduce Cz and/ or increase the mass (the regulations are currently doing both), the you reduce the sensitivity of the car to aero disturbances.

[wesley123]

What is this "sensitivity" anyways? To me, it implies that under conditions, the aerodynamic part is susceptible to losing downforce(or, let's say, it loses effectiveness of it's desired effect).

Thus, by this, losing more downforce would mean it's more sensitive. I'd say that a wing that generates 10 points of downforce loses more points according to the condition than a wing that generates 1 point of downforce.

If it was an issue, I guess they would have balanced it out by running less front df, or bolting on more rear df.

[Tim.Wright]

Sensitivity is the change of one parameter (e.g. grip) due to the change of another one (e.g. airspeed). In mathematical terms its a derivative.

In the case I described above there are 2 sensitivities acting in series in the chain that goes from Windgust > Car performance. These sensitivities are: ChangeDownforce / ChangeAirspeed & then change in AccelGrip / ChangeDownforce. Both of these become less sensitive as you reduce downforce.

[Andres125sx]

Can´t explain it better than Tim, but I´ll try anyway

As Tim said the higher downforce a wing/car produce, more dependant the car is to aero, so it will be more sensitive to wind gusts

Imagine some extreme example, a street car wich does not produce any downforce is not any sensitive to wind gusts because since it doesn´t produce downforce wind will never change grip. Well it will be disturbed because wind will literally push the car due to the box shape most cars have wich is anything but aerodynamic, but won´t change grip

OTOH a F1 car wich produce big amounts of downforce will be disturbed because with aerodynamics it´s not speed what matters, but aerdynamic speed. This means with no wind ground speed and aerodynamic speed are the same, but then a wind gust from the rear will suddenly reduce aerodinamic speed even if ground speed is the same, so downforce will be reduced too. If it was a plane, it would be stalling and falling down, since it´s a F1 car grip will be reduced and depending on the amount it could cause a slide/oversteer/understeer depending on the exact situation


So if you want F1 cars to resist wind gusts aero should be reduced so they´re not as dependant to their aerodynamic speed as they are now. That´s the reason they´re constantly reported about wind speed and direction, with front wind they can brake a bit later than usually due to the increased aerodynamic speed/downforce, while they must be carefull if the wind comes from the tail because the reduced airspeed/downforce will reduce grip/braking power and they´ll end up on the gravel if they don´t brake a bit sooner

[maxxer]

Thanks for the clear explanations guys