NOW THAT WAS A CAR
Under the skin of the car that powered Lewis Hamilton and Mercedes to a 2018 championship double
The title-winning Mercedes W09, with special Gorgio Piola analysis
NOW THAT WAS A CAR
No. 74
Abit of a diva” was Toto Wolff’s now-infamous assessment of Mercedes’ 2017 car, the W08. A championship winner, no less, and yet it was prone to the odd mood-swing; the long-wheelbase concept struggled to perform on the full gamut of circuits on the calendar, especially compared with the more amenable and rapier-sharp Ferrari SF70H. Although a considerable and consistent factor in the title fight, the Prancing Horse wasn’t quite as capable of producing moments of sheer brilliance to that year’s Silver Arrows. So, if only Mercedes could manage more of them…
With the threat of Ferrari looming larger than ever, Mercedes needed to build on the successes of the W08 ahead of 2018. The W09 was built on the theory of evolution, not revolution, and retained the same wheelbase. Mercedes wanted to ensure the whole package was simply a stronger, faster and more consistent version of the previous model.
Continuing with a similar design philosophy, Mercedes employed the same distinctive tapered nose section to take advantage of the increased airflow to the front of the floor, albeit refined to include a smoother transition to the front bulkhead. The aggressive front suspension was also kept, with the front wishbones raised as high as possible to minimise blockage to the sidepod inlets, reducing the impact on cooling.
While Mercedes looked to optimise an already successful concept, that’s not to say they were reticent to make largerscale changes. Taking a leaf from the Red Bull playbook, Mercedes raised the W09’s rake [the ratio of the car’s front to rear ride height] by just under half-a-degree, to coax extra performance from the diffuser. The aerodynamicists in Brackley tightened up the rear bodywork too as the shark fins atop last year’s car disappeared, making sure the internals were packaged as closely as possible to bolster the aero efficiency of the car. Tweaking the suspension layouts also assisted with aerodynamics, while the halo’s inclusion required a quick chassis redesign in order to accommodate the new load paths determined by the FIA’S new crash tests.
Under the corset-tight engine cover, the Mercedes High Performance Powertrains team produced their best work yet. Tasked with coaxing more grunt out of the most successful package of the modern turbo era, they overhauled the engine infrastructure to improve durability – the 2018 rules allowing a maximum of three power units per season – while the engineers also had to boost the power output to cover off the threat of Ferrari. That said, the start to the season was tentative, and it took until the fourth round for Mercedes to record their first victory of the year when Lewis Hamilton took advantage of a Valtteri Bottas puncture to win in Baku.
Extracting the maximum from the tyres seemed to be the biggest bugbear in the early stages. The “diva” still proved highly strung in high-stakes situations and rear tyre wear was a particular problem. Sebastian Vettel’s excellent early form in qualifying also suggested Mercedes could no longer claim to have the best engine – for the first time in the V6 hybrid era.
Keeping the rate of development throughout the season almost constant, Mercedes’ endeavours gradually delivered more success. Instead of plonking on a massive upgrade at Barcelona, they produced a series of small changes to the aerodynamics, yielding a second successive win for Hamilton. In Austria, the sidepods were tightened up further – although a strategic miscall and subsequent fuel pressure problem for Hamilton ended his hopes of a win.
It was in extracting the maximum of performance from the Pirelli tyres where Mercedes placed the bulk of their attention, as the team identified a new weakness in working with the new wider tyres first introduced for 2017. The moving goalposts as Pirelli revised their compounds for ’18 ensured Mercedes had to recalibrate again.
With a leave-no-stone-unturned approach, Mercedes increased their momentum with the W09, and the prudent, patient update strategy, built on continual gains, started to pay real dividends – especially in the second half of the
NOW THAT WAS A CAR
No. 74
THE MERCEDES W09
season. At Spa, after the summer break, they rolled out their biggest upgrade package: Brixworth turned out a boosted power unit, while Brackley produced a new wheel design, with raised sections to help draw excess heat from the tyres.
That design was augmented with a system to blow air through the wheel, and the air brought into the rear upright hub to cool the brake assembly was also used to extract heat from the rear wheels. Keeping the rear tyre temperatures down was key to Mercedes’ dominance at Singapore, a circuit on which they had often struggled. Hamilton’s pole lap there was one of beauty, and the ability to thread his W09 through the narrow streets with such perfection owed much to this important tweak. Mercedes continued to chalk up victories before their novel solution was rumbled, and they reverted to a more conventional setup for Austin and Mexico, to counter the possibility of a Ferrari protest. Although both drivers suffered increased tyre degradation without the system, the team continued to test it in practice, making changes to the internal flow in the wheel assembly ahead of Brazil.
There Mercedes clinched a remarkable fifth consecutive constructors’ championship crown. With those many months of continued fine-tuning, development and innovation, Mercedes once again turned their diva into a star.