Mclaren Mercedes MP4-25

[aral]

F1 endplates are 'hollow', they differ in cross section and hence are formed of two skins over a honeycomb and rohacell core.

If there was a foam or honeycome interior, there would be evidenc of this in the photos. If a filling is used, the CF has to bond to it, so the remnants would be clearly visible. This still, to me, appears to be simple delamination.

No, their hollow with rohacell (the white stuff in the pics) or honeycomb between the skins.

Thanks for foto of a Force India end plate. Yes that has foam. But look at the fotos shown of the Mclaren, there is no evidence of foam, which as I said, would be adhering to the CF, as in the F1 endplate. Also, the FI endplate did not react in the same way as the Mclaren endplate. FI shattered, Mclaren distorted.

[Richard]

You can see the infill foam on the images posted earlier:

[aral]

You can see the infill foam on the images posted earlier:

Thanks, I certainly hadn't noticed that earlier. So it appears that maybe the bonding of the edges was not strong enough.

[imightbewrong]

You can see the infill foam on the images posted earlier:

Thanks, I certainly hadn't noticed that earlier. So it appears that maybe the bonding of the edges was not strong enough.

Strong enough for what? A shunt against the wall? The wing broke, it has to give way some where when the force is too high. The wing is not designed for those kinds of horizontal forces.

[Just_a_fan]

a) the end plates are most certainly structural, unless you believe McLaren are magically suspending the upper element in the air.

I'm fairly sure the two elements are connected by a plate which is then bolted to the large aero endplate. Certainly this appears to be the case from the various photos hereabouts.

[forty-two]

did anybody else hear what ted kravitz had to say about a new rear wing aimed at stalling BOTH rear wing elements for korea?

Yes, I heard that too. I thought at the time it was a mistake on Ted's part, but it got me thinking.

If you were to stall the main element, could this stalling also affect the flow around the flap? I would have thought that stalling the main element would probably cause the flow around the flap to also detach?

Perhaps some of the Aero guys could advise?

[747heavy]

I read about that McL plans a wing with 2 F-duct slots on another forum, not sure if it´s true or not.
Why would they do it?
I´m not sure off course, just some thoughts.

If you have flow seperation on a wing or a body, and the wing cord is long enough, the flow can/will reattach to it again.

THerefore if they plan, to stall the mainplane maybe further forward, they need to blow the flap, to keep the flow seperated.

OTAH, there will still be airflow through the slot inbetween the main plane and the flap, even if they stall/seperate the flow on the underside of the mainplane, which could still follow the flap underside upward.

As they can´t close the gap (as teams did in the past with there first version of stalled rear wings) they may need to "blow" the attached flow away again (second F-duct slot on the flap underside) to achieve total seperation and minimum drag.
As Korea seems to have a very long straight, where every km/h topspeed counts, this is maybe the reason, to try to have as little drag as possible, and is worth the extra effort for a twin F-duct slot.

But I don´t know for sure, could be wrong
Just my two cent.

photo/CFD of reattached flow after seperation on an aeroplane wing




EDIT: corrected photos(CFD into photo/CFD

[forty-two]

Isn't the top image of a wing with flo-vis all over it and not CFD?

If so, it's interesting that this happens to have radioactive-green flo-vis, just like McLaren did up until recently.

Interesting theory though, seems to make sense to my untrained brain.

[747heavy]

yes it is - first photo flow viz (thats why I say photo/cfd)
AFAIK you use/can use ultra violet/black light in some windtunel tests to make
it better visible.
I´m resonable sure the first photo is taken with "black light", so see a bit viloet light at the leading edge.

some thick oil will do the trick as well:
shows the same thing, seperation bubble and reattachment on top of an glider wing

[Twaddle]

I doubt the flow would reattach in the case of an F1 wing, since the action of the main element is required to allow the flap to function in the first place. It would depend on how badly the air flowing through the slot is affected. Tbh, I can picture it both ways in my head, but without seeing some CFD of it would definitely think detachment from both elements is the most likely option.

[marcush.]

You can see the infill foam on the images posted earlier:

Thanks, I certainly hadn't noticed that earlier. So it appears that maybe the bonding of the edges was not strong enough.

Strong enough for what? A shunt against the wall? The wing broke, it has to give way some where when the force is too high. The wing is not designed for those kinds of horizontal forces.

sorry but what we see here is a very unlikely failure mode for a core with two skins laminated to it.You can see the part bending and shearing of a skin completely?that would be a complete mess of that parts construction...so done by
whom? hopefully not the same guy who did the structural parts...More likely we see on the inside the tearoffcloth preparation for the bonding of two halves and the black edges are the bonding substance.

[mep]

Instead of a second slot they could just mount a simple vortex generator to the front of the main plane over the full lenght.
This is done on model gliders.

[lolzi]

Hmm not at good start for mclaren.
But in the turn-in to the corner where Hamilton crahsed the inside wheel had much less angle than the outside wheel. It was clealy visable on the slowmo replay.
Usualy the inside wheel has much more angle than the outside wheel ... Perhaps something had broke before he turned into that corner???

Someone has been listening to what Kiesa has to say. I don't know how he can miss the fact that every single F1 car we saw had the same "reverse" Ackermann angles. The commentators really should look on the screen sometimes.

[Confused_Andy]

edit: nevermind

[MikeFromCanada]

Interesting comment by LH in an interview on Formula1.com:

The good news is that the rules permit us to change the gearbox for Korea without getting another grid penalty.

I was not aware of this at all. The rules have some kind of "room for error" so to speak?