The tech that decided the 2018 F1 title fight

The closest championship fight of Formula 1's turbo-hybrid era so far featured an incessant development race between Ferrari and Mercedes, in which various new concepts played a big part.

Here is our analysis of the key technical points, and the upgrades that worked or that backfired, plus a look at the rest of the field's 2018 development efforts.

Mercedes

Rear suspension

Mercedes was the only team to raise the pick-up point of its rear upper wishbone in 2018, a move that improves both the downforce level of the car and the consistency with which it is delivered.

The champion team went for a more-inboard and higher pick-up point. The pullrod pick-up appears to be just below the wishbone pick-up, allowing better system stiffness without adding weight. This allowed Mercedes to move the lower wishbone higher and away from the diffuser upper surface, creating better airflow over the top of the diffuser.

This, in turn, helps to get more airflow out of the diffuser itself and improves overall underfloor performance. More importantly, it removes the blockage of the outboard end of the wishbone and moves the pullrod inboard and upward that little bit, allowing Mercedes space to use rear brake ducts with more turning vanes. These improve the performance of the outboard area of the diffuser and also produce downforce in their own right.

This load goes directly onto the tyre contact patch, so there is no time lag in the grip this produces as the suspension moves up and down over kerbs and bumps. Also, under braking, when the rear of the car starts to rise and semi-unloads the rear contact patch, this load, directly onto the wheel and tyre, is more consistent and improves the reliability of the rear grip and corner entry.

Austrian GP update

Mercedes introduced a major upgrade package for the Austrian Grand Prix, including a new rear wing and endplate.

It was very similar in concept to what McLaren uses in that the transition between the lower, narrower section to the upper, wider section of the endplates has now become a louvred panel, helping to expedite the airflow from below the undersurface of the rear wing. It also manages the airflow spilling around the rear tyres, reducing the negative effect this turbulent airflow has on the rear wing's undersurface. Both of these changes make the rear wing more efficient.

Mercedes also introduced a new vane package around the leading edge of the sidepod. This is much more complicated than the previous version, and seems to use the same philosophy as the Ferrari sidepod-inlet system.

The objective of this package was to improve the performance of the sidepod undercut. Making this area work more efficiently improves nearly every other area of the car, including the front wing, the underfloor, the Coke bottle and, in turn, the diffuser.

Front suspension

Packaging the front suspension of a Formula 1 car is no easy task. There are just so many components to find space for, including the pedals, master cylinders and the driver's feet.

The 2018 Mercedes was no exception. It had the common top-and-bottom carbon wishbone and a carbon pushrod operating inboard rockers (1). Where the black top part of the pushrod changes to the silver part, there are shims (slightly darker silver) to alter the ride-height. As the angle of the pushrod is about 45 degrees, adding a 0.5mm shim raises the ride-height by roughly 1mm.

Looking at the car from the front, it has torsion springs on both sides (3). The left-hand torsion spring is splined into the machined-out rocker. A torsion spring is a round bar or tube with a spline at each end, one end anchored to the chassis at the driver's feet and the other end to the rocker.

When the suspension moves down, it twists the bar and the stiffness this creates supports the car. A torsion spring that is shorter, with a larger diameter, or a thicker wall, increases the vertical stiffness.

As the two additional rockers (4) are joined together in the middle with a solid link that effectively creates a third connecting rocker to help the other two drive the anti-roll bar, the small-toothed plate on the right-hand-side rocker is to locate the torsion spring to that rocker. Having this small plate allows adjustment so there is no preload on the system.

The interesting thing is where Mercedes has fitted the front anti-roll bar. It is inside the left-hand torsion spring (3 indicates left and right torsion springs). Its lower spline fits into a spline on the inner diameter of the left-hand torsion spring and its top spline is driven by the small-toothed plate.

When the car sits on the ground and the aerodynamic force builds up, the left-hand rocker rotates clockwise. The right-hand rocker rotates anti-clockwise and, with the solid link connecting them in the middle, they rotate at the same ratio, closing the gap between them, acting as a central damper. When the car reaches a certain speed, that central gap becomes zero and the car sits on the silver mesh-style bump stop. In a straight line, this reduces the car's vertical movement dramatically as this bump stop is very stiff.

But in a right-hand corner, when the chassis rolls, both left-hand and right-hand rockers rotate anti-clockwise. This twists the anti-roll bar. In this condition, the sum of anti-roll bar and the torsion spring stiffness gives the car its total roll stiffness.

Front wing

Following the summer break, Mercedes adopted the philosophy that if one is good, two must be better - it added another curved vertical turning vane to the front-wing assembly.

Two vanes work in conjunction with the front-wing endplate and together they set up an airflow-turning moment to move more mass airflow around the outside of the front tyre. This means that less-turbulent airflow goes between the inside of the front tyre and the chassis, allowing the front wing and the leading edge of the sidepods to work more efficiently.

Mercedes wheelrims

The controversial Mercedes rear wheelrims first appeared at the Belgian Grand Prix, and at the Mexican GP the team asked stewards to investigate them, resulting in them being ruled legal.

It's always difficult to quantify what is a moveable or moving aerodynamic device. The basic principle of cooling a brake disc by passing air through the holes in the disc means that, like the wheel, which at the very least has spokes, they are a moving aerodynamic device. But they are not moveable and the geometry is consistent when the car is stationary. Adding holes in the wheels is just exaggerating the wheel-spoke design.

Managing the tyre temperatures for both one lap in qualifying and over the full race is not easy. You want the tyres, especially the fronts, to warm up quickly for a qualifying lap, and over a race distance you want the rears in particular not to overheat.

It is fairly easy to get the rears to come up to temperature by just spinning the wheels, but you don't have that option with the fronts. So getting them up to temperature is all about using the brake-disc temperatures to influence the wheelrim temperatures, which increases the tyre temperatures.

That's the reason why Mercedes has concentrated on only the rear wheels. Basically, it has vented some cool air directly from the brake-duct inlets through the wheel spokes just outside the diameter of the wheel-retaining nut. This acts like an insulator, reducing the heat transfer that the hot brake disc and axle have on the wheel mass.

With the brake discs running at something like an average of 650C and even higher just at the end of braking at corner entry, the cooling air is then carrying some of that heat with it through the wheelrim.

Ferrari

Mirror mounts

Ferrari briefly ran a mirror design that required an extra vane for support, which it was asked to remove for the Monaco Grand Prix as it could offer an aero advantage. This resulted in this revised version being introduced, using the halo to mount the mirrors. The only reason the extra component was there originally was to improve the aerodynamics.

Canadian GP bargeboards

Ferrari's small changes on the bargeboard assembly for the Canadian GP added up to a decent performance gain. As you find a little problem with the airflow attachment on one surface, you might need to alter the chord length of that component. Ferrari has continued the concept of slot gaps further rearward. The trailing edge is now curved as opposed to vertical, and Ferrari also altered the footplate area, so now has an optimised bargeboard package.

French GP front wing

The biggest change on Ferrari's French GP front wing was the short slot gap in the main plane just below the V-Power sticker shown in the inset. Now it continues along its full length, making the main plane into two shorter-chord elements.

The longer-chord main plane was introduced mid-season last year and was something I questioned at the time. Yes, Ferrari will probably get more downforce from it, but it will be that bit more pitch-sensitive. So it really depends on what your car can live with overall. The new version will be more driver-friendly but may induce a little bit more understeer.

The outer flaps (black section) also have a gentler transition where they join the red parts of the flap. The trailing-edge gurney flap again is more progressive as it increases in size going outwards. These changes will be to reduce sensitivity issues, as the gentler the transition, the less chance of getting some aerodynamic crossflow.

Ferrari also had a new floor, with detail changes to the forward delta-wing areas. The 'L' slot gaps have now been reversed, increasing the amount of airflow that will be pulled through them. This, in turn, works the underneath surface of these wings harder, allowing them to produce more downforce. This modification will have been made possible by the changes to the front wing. With more consistent airflow through the inner edges of the front wheels feeding this area of the underfloor, the challenge would have been to use that extra airflow to improve underfloor performance.

British Grand Prix floor

Ferrari's floor-development programme has been non-stop, and the package introduced for Silverstone closed the gap to Mercedes. Ferrari has concentrated on the area in front of the rear tyre and the outer section. Combined with the vortex that is set up by the trailing edge of the bargeboards, this area works like a skirt that seals the underfloor from airflow leakage down the sides. This allows the diffuser to pull the airflow it requires through from the front of the floor.

Ferrari's failed floors

Over the Japanese and US Grands Prix, Ferrari introduced two new floors but neither made it to race day. Either Ferrari wasn't getting what it predicted from them or the development direction had reached a crossroads. I wasn't sure what it expected to get with the detail changes it had made to the slots around the tyre contact patch from the Suzuka development.

At Austin, that area was modified again - with a few more turning vanes added. The idea of this Coke-bottle area and the underfloor is to get as big a pressure differential as possible across the floor structure, with low pressure underneath and a higher pressure above. But you need to maintain good high-speed airflow inside the rear tyre to help the performance of the rear wing and diffuser.

The longitudinal slots pull airflow from the floor's upper surface, and act like a skirt, reducing the amount of airflow pulled under the floor. These small vertical turning vanes are intended to set up an outwash vortex along the floor's outer edge, similar to the effect of the trailing edge of the bargeboards and front-wing endplates, to improve the performance of the slots and underfloor.

The rest of the field

Red Bull

Over the season, Red Bull introduced small modifications to the leading edge of its underfloor. At the beginning of the year, it had a package of three vertical turning vanes and one larger one on the forward-facing fingers of this area of the floor. In France, it was reworked and had five plus one, which are further rearwards.

Any improvement helps the performance of the front wing, and helps the airflow along the outer sides of the underfloor act like a skirt. This reduces the amount of airflow that leaks into the low-pressure area underneath the car, improving the performance of the underfloor.

Renault

I called the updated front-wing assembly that Renault introduced in Hungary the 'Venetian blind' - and it looks just like that. Starting with the endplate, the trailing edge has five outward turning vanes to strengthen the outwash airflow in this area. The vertical section of the wing flaps is also slotted to improve the consistency of the outwash flow.

The adjustable inner section of the flaps (yellow part) is now much smaller. This has a positive reduced flow-characteristic change on the outboard section when the wing angle is changed, but also makes it more di­fficult to alter the car's aerodynamic balance.

Haas

Haas introduced a major aerodynamic upgrade package in Canada, and part of this was the bargeboard area. The red arrow highlights the small turning vanes on the leading edge of the underfloor. These are very similar to what Red Bull had run, and each one is designed to set up a vortex that goes underneath the flat area of the underfloor to improve its overall performance.

The outboard horizontal louvre section is fairly similar to what Haas ran before, just a bit more detailed and aggressive.

Toro Rosso

Along with the front-wing endplates, the bargeboard area of an F1 car has been allowed to get out of hand. If anyone wants to reduce the costs and improve the show, these two areas should be addressed very quickly.

This drawing shows you the number of turning vanes that work together to improve the underfloor performance. It is a fantastic feat of aerodynamic flow-structures optimisation but, as soon as you get close to another car and the airflow to these components gets any level of turbulence, this aero-flow structure falls over and reduces the performance of the other aerodynamic components it was influencing.

The other, and probably more important, issue with this area of the car for the teams themselves is that there are no sponsors because there is no surface that can be seen from different angles. This problem is being tackled with the 2019 regulations.

McLaren

In Spain McLaren introduced what it called its definitive 2018 car, the most obvious part being the new nose section.

The previous nose was the same width as the front of the chassis, using very long wing-mounting vanes with vertical slots to help pull as much airflow as possible under the nose and chassis central section. The new nose is narrower and has small turning vanes running up the top outer corners of the nose. These will help turn the airflow and keep it attached to the sides of the nose.

The leading-edge inlet section is very similar to Red Bull's and the side inlets very similar to Force India's. They exit under the nose along a horizontal slot that is divided into three sections. This again takes more mass airflow and directs it to the undersurface of the Mercedes-style duck bill.

All of this is to increase the mass airflow that is going under the centre section of the chassis and to improve its direction as it comes off the trailing edge of the duck bill. The duck bill is mounted on a vertical vane splitting the airflow left to right. This could also be a bit of a problem in turbulent airflow or crosswind conditions.

Force India

Force India added a small T-wing to the trailing edge of the engine cover just above the radiator cooling exits as part of its major Melbourne upgrade following a performance shortfall in testing.

There is also a small gurney flap at the outer end of this component to make this area of the T-wing work harder. This T-wing will produce a small amount of downforce, but more importantly will help tidy up the airflow going to the underside of the rear wing.

Sauber

Sauber ran turning vanes on the upper part of the front wishbone, a concept later applied by Mercedes to its own front suspension. What you want to do here is pull air into the low-pressure area behind the front tyre because it's a very turbulent area, and the more you fill up that hole created by the tyre, the less work the parts in front of the sidepod have to do. The brake ducts also work towards this.

Also, when the tyre is rotating and the airflow is navigating it, you create a bit of lift on the tyre's upper surface, so this also helps to eliminate some of that negative. For this to be legal, you have to comply with the regulation requiring an aspect ratio of no greater than 3.5:1 in suspension components.

Williams

Mexico was the most difficult race of the season for cooling. The air is pretty thin so it reduces downforce, drag and cooling quite dramatically. But with the engine able to create 160bhp from electrical harvesting and having a turbo, some of the engine power is retained.

Williams took a dramatic approach to its cooling there, as its rear exits were fairly brutal even compared to what it ran in Hungary.