McLaren MP4-28 Launch Review

With car launches nearly every day this week, we finally feel the return of F1 races. People are saying ‘It’s exactly the same as last year!’ everytime a new car reveals, even though they all know that 2013 is not a year for revolution. In McLaren’s launch, Jenson said that ‘under the skin, it’s so different’ – well we don’t really know before the Jerez test, but through bare eyes, we can see several detail changes on the new seasons car.

First of all, if you haven’t watched their launch video, you should really do it now! They have a brilliant built-up to the revealing of MP4-28:

With little change in regulations, one thing most team would do is trying to steal some good ideas from other cars last season. In terms of this, McLaren has somehow adopted Ferrari’s pull rod suspension and Red Bull’s rear suspension merging with driveshaft and track rod.

Covered Step Nose

The most obvious change is the covering of step nose with modesty panel. Step nose appeared in F1 since the 2012 season, when FIA modified the height limitation for nose cone and monocoque due to safety reasons. The 2012 regulation has a 550mm limitation for nose cone and 625mm for monocoque. As it’s beneficial to get more air flow underneath the car to feed into the diffuser, most teams are pushing to upper limit for both nose cone and monocoque. And in order to make up for the margin between them, step nose came out as the solution. The step doesn’t look good and there could be slight aero deficiency as the surface is less streamline like. So in 2013, regulation allows using of a modesty panel to cover the nose. It’s basically a thin carbon fibre panel that doesn’t have any structure function (it simply breaks down during front impact). However, the penalty of using this panel would be additonal weight at the front of the car. It’s the team’s choice to decide whether to use it or not considering its aero and aesthetic benefit and weight penalty.

McLaren MP4-28 Nose Cone

MP4-28 Nose cone with modesty panel

Original Step Nose without Modesty Panel

MP4-28 Original step nose without the cover

Front Pull-rod Suspension

This was what Ferrari used last year (this year as well). Pull-suspension is basically an upside-down version of push-rod suspension (well not exactly, but you may understand it this way..). With the chassis and nose cone lifted up for maximum aero benefit, for stability, it’s good to lower down centre of gravity with a pull-rod suspension as all those springs and dampers are mounted at the bottom side of the nose. Actually McLaren must have made a whole change in the front part design due to the change of suspension.

McLaren MP4-28 Pull-rod suspension

McLaren MP4-28 Front Pull-rod Suspension

Rear Suspension Integration with Driveshaft

This was a Red Bull idea implemented since the development of RB5!  It basically utilise one of the wishbone to cover up the rear driveshaft. The covering of this part would make it more aerodynamically desirable. It smooths out the air at the rear of the car, therefore good for the efficiency of rear diffuser. From the picture below, you can see a very thick wide structure of the wishbone, which houses the whole driveshaft.

McLaren MP4-28 Rear Suspension

McLaren MP4-28 Rear Suspension

*Pictures from AMuS

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What Makes RB8 Faster – Flexi Front Wing

I’ve mentioned in a previous post on McLaren Spa Updates that McLaren is possibly using Flexi front wing. The flexi part is not new to F1 cars – Red Bull used it back in 2010, other teams tried on this principle as well although not all of them achieved preferable results.

How it works?

Basically, at moderate speed, the front wing runs at a relatively high angle of attack, maximizing downforce generated. At high speeds (long straights), the outer part of the wing tilts pack, reducing AoA, therefore reducing both downforce and drag (Although Research on Honda 2007 shows that there is scarce decrease in drag, although downforce deduction is noticeable). The shedding of downforce promotes better aero balance of the car – as what Mercedes want to achieve with their FW DDRS system. Flexi front wing also helps guiding the air around the wheel inward underneath the car, subsequently enhancing diffuser performance.

While Adrian Newey highlighted the loss of downforce due to ban of EBD as their major problem this year, the Flexi front wing should be one of the compensation they found.

In this December’s Racecar Engineering there is an interesting article regarding the composites used for flexi front wing. Basically, teams are using FEA (Finite Element Analysis) to evaluate material deformation under loading – they’re seeking for an optimised aerodynamics design that could meet all the FIA crash test requirements.

Picture from RaceCar Engineering

Front wing flexing back as shown in the green curve

As illustrated in the picture above, flexi wing can have less bending deformation and more twisting/tilting at the rear of the wing.

What about RB8 Flexi Front Wing?

RB8’s new front package is actually quite unique – in additioin to the wing flexing, they seem to have a rubber nose that can deform/tilt under loading. This pitstop from Vettle in Abu Dhabi caused lots of discussion as the mechanicseem to flex the nose when removing it.

However Vettle’s front wing was slightly damaged at that point, which may exagerate the nose tilting observed. Another GIF from Webber during the race does show quite large oscillation of the front wing as it goes through kerbs.

 Webber’s front wing oscillating in Abu Dhabi

Generally speaking, RB8 now has a really flexible front package – the tip of nosecone can bend downwards, also the outer section of front wing tilts back at high-speed.

Besides the benefit of downforce reduction and airflow enhancement around/underneath the car, Red Bull’s rubber nosecone may also create a mass damper effect, whereby car bounce is deducted, enhancing chasis stability.

The mass damper effect is well demonstrated in the video below, as can be seen, with a mass damper extended out, bumping on the main structure is significantly reduced.

The mass damper idea is not new to F1 – used by Renault back in 2005, although it’s later banned by FIA in 2007 (More to read if you’re interested in mass damper effect: J-dampers in Formula One). However, Red Bull’s Flexi front wing is an innovative idea extending this principal. The improvement of chasis stability also supports more stable aerodynamic performance for RB8.