Mclaren Mercedes MP4-25

[raymondu999]

I distinctly remember they brought a non f-duct rear wing to Bahrain in case their f-duct was declared illegal

[aral]

They don't really have much alternative. They run so little wing at Monza that the drag penalty is minimal. The F-duct is more likely to disrupt things. It'll be interesting to see what rear wing they have for this.

McLaren have announced that they are removing the f-duct, for Spa.

not the havnt! its monza!!

It appeared on another website, that the f-duct was being removed from Spa. However, it has disappeared from that site, so they must have posted incorrect info. Sorry if I upset you all!

[marcush.]

I don´t get that really...the true sense of it is to have a good downforce level + lower drag.

Monza is a lot of breaking from very high speeds...you could use all downforce you can generate to heklp this.
Then there is lesmo curves ,parabolica high speed corners ...were youcould use some downforce...


would not a bit less wing but with F-duct be a very good choice ....of course dragwise you must be in the same league than non f-duct cars with their tiny rear wings...so they just did not wnat to develop this new wing for a single race or what?

[aral]

I don´t get that really...the true sense of it is to have a good downforce level + lower drag.

Monza is a lot of breaking from very high speeds...you could use all downforce you can generate to heklp this.
Then there is lesmo curves ,parabolica high speed corners ...were youcould use some downforce...


would not a bit less wing but with F-duct be a very good choice ....of course dragwise you must be in the same league than non f-duct cars with their tiny rear wings...so they just did not wnat to develop this new wing for a single race or what?

Maybe McLaren feel thet their version of the blown diffuser does not work in harmony with the f-duct, and it is a case of "one or the other". It looks as if they are giving up the struggle to reach the top, and are instead trying different solutions in the hope that they will find the right solution?

[segedunum]

They always could. It was no big deal to remove it...

It is a big deal to remove it. It's an integral part of the car and they would have needed a different rear wing to cope without it. For other teams that hasn't been so much of a problem since they added it to their cars and had separate rear wings they could develop without the system.

The reason why they haven't removed it before was that it would be too much hassle to come up with different bodywork and a different rear wing, minus the F-duct components. Now at Monza the disadvantages obviously heavily outweigh the advantages and the hssle, to the point where they'd be heavily compromised with the system.

Some like to believe the F duct has a compromise, but it doesn't.

It obviously is a compromise otherwise they'd be using it at Monza. To be able to run some wing with zero drag penalty would be a huge advantage there, and heaven knows McLaren need it, but they obviously can't achieve it.

Without getting some numbers from McLaren it's difficult to ascertain whether the F-duct really allows them to run wing with no compromise, but this points the fact that there is a compromise.

[marcush.]

oviously with their lowest drag configuartion with f duct they would be at a diasdavantage with their top speed compared to what the competition will be doing or what is more likely their simulations have hinted at a better solution for the monza park...as they have visited the venue for some years it seems reasonable they got their calculations right...

[gibells]

McLaren live and die by what their simulator says, and that would include braking as well as top speed. It will be very interesting to see how the 25 performs without the F-duct.

[ell66]

They always could. It was no big deal to remove it...

It is a big deal to remove it. It's an integral part of the car and they would have needed a different rear wing to cope without it. For other teams that hasn't been so much of a problem since they added it to their cars and had separate rear wings they could develop without the system.

The reason why they haven't removed it before was that it would be too much hassle to come up with different bodywork and a different rear wing, minus the F-duct components. Now at Monza the disadvantages obviously heavily outweigh the advantages and the hssle, to the point where they'd be heavily compromised with the system.

Some like to believe the F duct has a compromise, but it doesn't.

It obviously is a compromise otherwise they'd be using it at Monza. To be able to run some wing with zero drag penalty would be a huge advantage there, and heaven knows McLaren need it, but they obviously can't achieve it.

Without getting some numbers from McLaren it's difficult to ascertain whether the F-duct really allows them to run wing with no compromise, but this points the fact that there is a compromise.

The only reason I see why the f-duct is'nt being usd there is due to just how flat the rear wings are at monza, i doubt they could even properly fit the thing on there.
Iv noticed you're about the only person iv noticed on this board continue to say it brings compromises, but i see ZERO eveidence of that anywhere.

[747heavy]

I will not claim, that I know the answer, but IMO the F-duct only works if you run a rear wing which is over it´s critical angle of attack &/or camber, which means it will see flow separation/stall on the low pressure side if not "blown" (reenergizing the flow).
If your base wing configuation is not critical (Monza setup) you wont gain from a F-Duct.

I understand what Marcus says, running more wing to gain under braking and in the corners, but maybe this gain does not outweight the drag penality.
The F-Duct in itself is quite bulky/draggy and the longer engine cover/fin will create some additional drag in itself, purely by surface friction (wetted area).
I guess McL´s simulation show, that you lose more due to the extra drag, then you win back in the corners & under braking.
Especially now with the V8´s and the rev limit.

I remember that back in the F3000 days (2003/4) the car in lowest wingsetting would still produce too much downforce/drag for Monza.
As you could not take off the wings (by the rules) one team mounted the lowest element upside down, and gained a huge straight line speed/laptime advantage.
They where later dsq for it, but it proved, that drag reduction, gains some advantage in Monza.
Will be a interesting weekend/race.

[wesley123]

I don´t get that really...the true sense of it is to have a good downforce level + lower drag.

Monza is a lot of breaking from very high speeds...you could use all downforce you can generate to heklp this.
Then there is lesmo curves ,parabolica high speed corners ...were youcould use some downforce...


would not a bit less wing but with F-duct be a very good choice ....of course dragwise you must be in the same league than non f-duct cars with their tiny rear wings...so they just did not wnat to develop this new wing for a single race or what?

Like i said, it would be stupid to focus on turns, as then you will be battling the red bull on those sections, you'll lose that without a doubt. So they increase their advantage they have and afaik always had, an straight line advantage, that means they will run as less drag as possible. On Monza there is way more to gain on the straights then in the corners, especially with an red bull that is good in the corners, with an set up wich is more aimed at cornering you will give up alot of time to the red bulls.

[raymondu999]

I think what they mean is that the f-duct, at these extremely low angles, doesn't work. And it might not even fit

[Afterburner]

I think what they mean is that the f-duct, at these extremely low angles, doesn't work. And it might not even fit

I agree, i doubt anyone can use a functional f-duct in monza.

last year monza rear wing:



Germany 2010 f-duct:


Canada 2010 rear wing:

[marcush.]

i perfectly understand the downfalls of having more wetted surface area etc. but this is always a fact with this setup,it will only show more pronounced because of the higher speeds as forces go up with the square of speed.
but even that small wing thingy they had last year will carry lots of drag at these speeds so the penalty they carry at the very high end of their speed envelope must be high..maybe it is as bad as above a certain speed the f-duct is no more effective and drag rises dramatically and you get drag inducing stalling?

[Richard]

All engineering design is a compromise.

In this case it appears that the compromise that is best suited for McLaren at Monza does not use the F-duct.

[raymondu999]

I'd think it'd be better to compare the rear wing with their Canada wing rather than Hockenheim