Mercedes GP W02

[andrew]

I very much doubt it.

When the wing element is returning to its regular position then surely it would be helped by the air flowing over it to close as it is hinged at the top?

Plus Rosbergs seems to work fine.

[feynman]

I think it may be the elctrics which could be causing the problems.

Reading Schumacher's comments, the element is not fully retracting immediately so I think it is an electrical fault that they havn't sussed out yet.

Did you post the correct link there?

Schumacher doesn't seem to mention the wing in his one quote, most of that article is Brawn, saying:

When you activate the rear wing system the flap goes up and the airflow stalls, then when the wing comes back it reattaches. We have some situations where it doesn't reattach immediately.

It's quite complex, there's some separation going on and I think it's a function of cross-wind, yaw angle and the angle of flow. We have what we call a ski ramp in the middle of the lower wing to make the rear wing a bit more stable. It's not just about downforce/drag, it's stability and response rate. The gain in straightline speed from our wing is quite substantial, we've just got this bit of instability.

That looks like nothing but aerodynamics to me. No-one mention electrics or mechanicals. All F1 wings are deliberately on the edge of stalling, it seems the disturbance and dynamics of snapping a flap shut provoke a marginal Mercedes design/set-up over the edge ... at least that's what I take away from what Brawn is saying there.

[andrew]

Yep, should have written Brawn!

It's what happens when you are half watching a film, playing guitar and posting comments at the same time. Multi-tasking does not work!

I was referring to the electrics in terms of the delay in the wing reattaching. The wing should close as soon as the brake pedal is pressed but it sounds like this is not happening

So the car is aerodynamically unstable along with a problematic ARW?

[Ferraripilot]

That's 2 races in row now where MB have failed to put together a reliable car. The week started great as did qualifying, but Q2 hits and Michael's wing goes sour, then Q3 hits and Nico's does the same. Must be a fundamental issue with the wing design?

The MB has fantastic top speed and was brilliant through S1, but everything else aero related and the car just isn't there. Perhaps they should follow Ferrari in getting a flexi wing going, run a soft front end, up the rake, and make the W02 a really short and fat Red Bull. I'm at a loss.

[hollus]

My German is getting a bit rusty, but I heard Schumi himself interviewed for RTL just after quali saying that the movable flap would not return to its usual position. That they had the problem already in practice, intermittently, and that they knew there was a risk of that failing in quali, but they had to try nonetheless. Then, in his last run in Q2 it went up and failed to go down again, so the car became quite "slippery".
Can any of the Germans confirm that?
I though the movable rear wing flap was supposed to be built with a fail safe mechanism, and a redundant one at that, so if it failed it would always return to the high downforce configuration?!

[Ferraripilot]

My German is getting a bit rusty, but I heard Schumi himself interviewed for RTL just after quali saying that the movable flap would not return to its usual position. That they had the problem already in practice, intermittently, and that they knew there was a risk of that failing in quali, but they had to try nonetheless. Then, in his last run in Q2 it went up and failed to go down again, so the car became quite "slippery".
Can any of the Germans confirm that?
I though the movable rear wing flap was supposed to be built with a fail safe mechanism, and a redundant one at that, so if it failed it would always return to the high downforce configuration?!

I read it was a delay in the wing going down from when the button on the steering wheel was released. Either explanation makes sense and would certainly make braking difficult to judge.

[mep]

My German is getting a bit rusty, but I heard Schumi himself interviewed for RTL just after quali saying that the movable flap would not return to its usual position. That they had the problem already in practice, intermittently, and that they knew there was a risk of that failing in quali, but they had to try nonetheless. Then, in his last run in Q2 it went up and failed to go down again, so the car became quite "slippery".
Can any of the Germans confirm that?
I though the movable rear wing flap was supposed to be built with a fail safe mechanism, and a redundant one at that, so if it failed it would always return to the high downforce configuration?!

Yes confirmed. MS said it stayed permanently in upper position.

There just remains the question if this is true. Maybe they just want to blame some part instead of admitting their lack of pure speed. Might be one of Haugs habits. Does anybody know the laptime of MS last try? It should be much slower if its true that the wing got stuck in upper position.

I wonder if the FIA shouldn't test those rear wings and prohibit the use when it doesn't work 100%. It's an absolute no go when such a wing gets suddenly stuck un upper position. Maybe the car should even be excluded from the race. It might sound harsh but maybe that’s what the team needs and deserves.

[feynman]

I doubt the drivers can even see the flap in their mirrors, and especially not going into a braking zone on a hot qualifying lap, and definitely not enough to gauge a few mm up or down.

They would be talking about the car *feeling* as if the wing had not gone back down, which aerodynamically speaking, if the airflow had not correctly reattached, then technically it makes no difference if the flap is still up or down, as far as the physics go, it feels identical, you don't have the downforce either way.


As for fail safe, I don't buy it, there's no such thing, yeah, it's supposed to snap back under aero load, but if a mechanical actuator twists and jams, there are still plenty of scenarios that could see a wing stay open.

[hollus]

OK, I just found that the reference to a redundant fail safe system was nowhere in the regulations (it was in some wish regulations ).
But still...

3.18.1

- When viewed from the side of the car at any longitudinal vertical cross section, the physical point of rotation of the rearmost and uppermost closed section must be fixed and located no more than 20mm below the upper extremity and no more than 20mm forward of the rear extremity of the area described in Article 3.10.2 at all times.
- The design is such that failure of the system will result in the uppermost closed section returning to the normal high incidence position.
- Any alteration of the incidence of the uppermost closed section may only be commanded by direct driver input and controlled using the control electronics specified in Article 8.2.

[Daffron]

The problem with the rear wing is the time taken for flow to reattach after DRS activation and not the mechanical movement of the flap itself:

Ross Brawn: “When you activate the rear wing and the flap goes up effectively the air flow stalls, it separates off the wing,” “When the flap comes back, then the flow reattaches. We’re having some situations where the flap comes back and the flow doesn’t attach immediately – it takes a bit of time before the flow reattaches. We’ve made some modifications since Melbourne, and it looked OK in practice, and it seemed to come back again during qualifying."

http://formula-one.speedtv.com/article/ ... ascinating

[feynman]

The design is such that failure of the system will result in the uppermost closed section returning to the normal high incidence position.

All that says is that if the actuator wasn't present, the wing would snap closed by aero-pressure, as opposed to any design that naturally prefers to stay open and has to be actively pulled closed.

There are dozens of fault-modes that would leave a broken actuator and it's accompanying mechanical/electrical/hydraulics jammed hard in the open position, in that case, the fact the air pressure really wants to try and snap the wing back down doesn't necessarily mean that's what will happen.

The mechanism is clearly strong enough to bruteforce and lever-open the flap all the way down the longest, fastest section of any straight, I don't see how the weaker aeroloads in a braking zone will be able to suddenly overpower any jammed-open actuator.

[Ferraripilot]

The problem with the rear wing is the time taken for flow to reattach after DRS activation and not the mechanical movement of the flap itself:

Ross Brawn: “When you activate the rear wing and the flap goes up effectively the air flow stalls, it separates off the wing,” “When the flap comes back, then the flow reattaches. We’re having some situations where the flap comes back and the flow doesn’t attach immediately – it takes a bit of time before the flow reattaches. We’ve made some modifications since Melbourne, and it looked OK in practice, and it seemed to come back again during qualifying."

http://formula-one.speedtv.com/article/ ... ascinating

It looks as if they put a black gurney along the top of the DRS element since Aus.

[ringo]

The wing didn't fail it just failed to return to the fully closed position.
I wonder if it's motor driven sometimes. It may have a repeatability error.

I don't think it's flow related this time, the team would know the exact displacement of the wing and let Shumacher know that it may be closing at 12mmm gap instead of 10, or 15mm ect. They know what's going on exactly.
It's more a system malfunction than a failure.

It needs to be a simpler system. If they want a clean look, they can go for the torro rosso solution. The end plate thing is probably prone to overheating and loss of accuracy.

[youtube]http://www.youtube.com/watch?v=iLVlP8qVEnU[/youtube]

[Daffron]

The wing didn't fail it just failed to return to the fully closed position.
I wonder if it's motor driven sometimes. It may have a repeatability error.

I don't think it's flow related this time, the team would know the exact displacement of the wing and let Shumacher know that it may be closing at 12mmm gap instead of 10, or 15mm ect. They know what's going on exactly.
It's more a system malfunction than a failure.

It needs to be a simpler system. If they want a clean look, they can go for the torro rosso solution. The end plate thing is probably prone to overheating and loss of accuracy.

Hi Ringo,

Ross confirmed after quali that it is a flow problem they have:

Ross Brawn “When the flap comes back, then the flow reattaches. We’re having some situations where the flap comes back and the flow doesn’t attach immediately – it takes a bit of time before the flow reattaches" “In Michael’s case in his qualifying lap there were several corners where the flow was unstable, and it happened in Nico’s case as well"

http://formula-one.speedtv.com/article/ ... ascinating

[andrew]

Interesting link here along with a nice view of the Merc rear wing.