McLaren MP4-26 Mercedes

[volarchico]

Just looked up the rules:
"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" It looks like it just needs the physical attatchment 20mm below the top, not really very specific, maybe a loop hole waiting to be expoited.

So the furthest forward it can hinge is 20 mm down and 20 mm forward of the uppermost/rearmost extremity.

[bot6]

With the aero pressure on the hinge, you would probably need a fairly thick hinge anyway, maybe 6-8mm in diameter. So that would leave 1.6cm of leeway to position the flap pivot point.

Then you also have to take into account that with a longer chord top flap, the air is "squeezed" in the 50mm gap between the flaps on a longer distance, creating more drag so a less efficient DRS.

That last bit would explain at least part of the difference between RBR and McLaren in qualifying as opposed to the race: McLaren's wing with the bigger flap is more efficient when closed (in race conditions), but Red Bull's, with the small flap, is more efficient at shedding drag when open which helps qualifying performance.

[beelsebob]

With the aero pressure on the hinge, you would probably need a fairly thick hinge anyway, maybe 6-8mm in diameter. So that would leave 1.6cm of leeway to position the flap pivot point.

Then you also have to take into account that with a longer chord top flap, the air is "squeezed" in the 50mm gap between the flaps on a longer distance, creating more drag so a less efficient DRS.

That last bit would explain at least part of the difference between RBR and McLaren in qualifying as opposed to the race: McLaren's wing with the bigger flap is more efficient when closed (in race conditions), but Red Bull's, with the small flap, is more efficient at shedding drag when open which helps qualifying performance.

I think this can be more easily explained simply by saying "the McLaren has slightly less downforce at the moment". The result – the RBR can open it's flap slightly earlier, and close it slightly later. The result is that in qualifying they get to use their flap more than McLaren do.

[bot6]

That advantage would carry onto the race though.

[beelsebob]

That advantage would carry onto the race though.

Not at all – in the race they aren't allowed to open the DRS in every single corner, reducing the speed advantage in each turn. Essentially, you're talking about later breaking and earlier acceleration in every single corner in qualifying.

[bot6]

Generally speaking, having more downforce helps you everywhere. Quali, race, FP, ... It just helps all the time, no?

[beelsebob]

Generally speaking, having more downforce helps you everywhere. Quali, race, FP, ... It just helps all the time, no?

When you get to dump a chunk of it in exchange for less drag periodically it gives you a bigger advantage.

As I suggested earlier in this thread – suppose you have a corner where RBR are drag limited both with the DRS open and closed; but where McLaren are drag limited with the DRS closed, but downforce limited with it open. In such a corner, McLaren would gain no speed by opening the DRS, but RBR would gain.

Extend this to almost every single corner next, because almost all corners have a point where the car transitions from drag limited to downforce limited and back and it all adds up to really quite a large advantage during qualifying.

[bot6]

So basically you're saying that because the RB7 globally has more downforce, it automatically loses more downforce than the MP4-26 when the DRS is activated?

That's a bit of a shortcut there. And dumping more downforce does not always mean losing more drag. It all depends on the way you do it.

[beelsebob]

So basically you're saying that because the RB7 globally has more downforce, it automatically loses more downforce than the MP4-26 when the DRS is activated?

That's a bit of a shortcut there. And dumping more downforce does not always mean losing more drag. It all depends on the way you do it.

No, I'm saying that because the RB7 globally has more downforce, it is able to dump downforce in more locations than the McLaren is able to in.

[bot6]

OK now I'm getting your point. And indeed that can help explain the quali difference VS race. But if the overall downforce was noticeably different, then at least part of that advantage would carry on to the race and on pure race pace, both cars seemed fairly even.

Maybe the slightly lower downforce on the MP4-26 is compensated by better driveability and mech grip, especially out of slow corners where that car really seems planted and seems like it has tons of traction?

[beelsebob]

OK now I'm getting your point. And indeed that can help explain the quali difference VS race. But if the overall downforce was noticeably different, then at least part of that advantage would carry on to the race and on pure race pace, both cars seemed fairly even.

Maybe the slightly lower downforce on the MP4-26 is compensated by better driveability and mech grip, especially out of slow corners where that car really seems planted and seems like it has tons of traction?

Agreed, and I think your explanation for why the MP4-26 makes up pace makes a lot of sense. As an aside - I don't think the McLaren is far behind the RB7 in terms of DF, I think a large chunk of the qualifying difference can be explained purely by Vettel being a single-lap specialist, and Hamilton having made a few --- ups in qualifying.

[Shaddock]

So basically you're saying that because the RB7 globally has more downforce, it automatically loses more downforce than the MP4-26 when the DRS is activated?

That's a bit of a shortcut there. And dumping more downforce does not always mean losing more drag. It all depends on the way you do it.

Don't think of it as Down Force but as drag, and where on the wing that drag comes from.

RB have a smaller flap and therefore can loose a larger % of drag from their rear wing when the DRS is activated than the McLaren.

[bot6]

I agree with you Shaddock, that was my point as to one of the many reasons the RB7 has the edge in quali.

But I also think the bigger flap rear wing is slightly more efficient when the flap is closed, which would give McLaren a slight advantage rear wing wise in the race. That would also help close the gap a little bit.

[BreezyRacer]

My guess is that McLaren needs a larger wing to match the downforce of the RB with the smaller wing elements. If that's the case then actually McLaren have the advantage in qually where DRS can be employed where ever you want to use it.

You can read into this, I guess, that the RB is perhaps better aero balanced than the McLaren, though the McLaren is performing well. If RB needed more rear downforce they could easily add a more aggressive rear wing. It seems that front downforce and grip is the limiter this year, so they are left with trimming the downforce at the rear to balance the car.

I'm sure we'll see a world of new aero packages in two weeks that could scramble things around a bit ..

[bot6]

The general shape of the rear wing is pretty much locked by the regulations, which is why they all look so similar. The only things that the designers can play with are the endplate shapes and the main profile / flap chord ratio.

Globally though, with the flap closed, they all give pretty much the same downforce with maybe a very slight advantage to the large flap one. The difference from one to the other rear wing is not enough to really change the balance of the car, they are all pretty much configured for max downforce within the regulations.