The Ferrari idea that shaped current F1 car thinking

That is exactly the story behind the S-duct in Formula 1. It was an idea that was thrust on to the track by Ferrari as something quite radical back in 2008, could not be carried forward because of new regulation, but has since made a return to now become the norm.

The Ferrari F2008 was the first car to feature this incredibly novel solution when it appeared at the 2008 Spanish Grand Prix.

However, looking back at the launch spec of the car, it was clear that Ferrari had the idea to feature it right from the off.

Ferrari F2008 front suspension

Photo by: Giorgio Piola

The chassis featured a cutout in the top surface that had been there since the car's launch, and had been covered by a wedge-shaped panel up until its new nose design arrived.

The new nose, the centre-piece to this design concept, featured a bellmouth inlet on its underside and an exit on the rear that not only aligned with the chassis cutout but also created another exit just ahead of it.

The overall intent of the 'S' duct is to tidy up the flow on the underside of the nose that leads to the bargeboards, the leading edge of the floor and the sidepods.

By adding an inlet under the nose at a point where the airflow becomes turbulent you can manage this problem, refocus it and then redistribute it in a less sensitive location.

As with any complex solution, the advantage created from the aerodynamic aspect of installing an 'S' duct solution has to outweigh the drawbacks, with the design and weight of the whole solution to be taken into account, especially when we consider this is a structure that must be able to undergo the rigours of a crash test.

What goes around, comes around

The 2009 regulation change was extensive, having an immediate impact on the downforce that the cars generated and how they did it.

The rule changes also prevented teams from adopting the Ferrari style of S-duct. There was a new stipulation that a single cross section of the nose must not feature any holes.

Further tweaks to the rules in this area were made after Mercedes used a front-wing stalling double DRS system. It was subsequently ruled that any aperture more than 150mm ahead of the front wheel centreline should only be for driver cooling.

There was enough scope, however, for teams to try to regain the advantage of the S-duct, with Sauber the first to re-introduce the concept.

Even with a very severe limitation caused by the 150mm rule, plus the fact the ramp was very brutal, the gain was still enough to make the solution worthwhile.

Since then, the idea has been refined further with every team approaching it slightly differently – but all of them aiming to deliver the advantage that Ferrari unlocked all the way back in 2008.

It took a while for the ‘S’ duct solution to reappear following the introduction of new regulations in 2009. However, in 2012, in line with some further alterations to the regulations, it was Sauber that was first to conceive a similar solution.

The new nose height regulations introduced by the FIA had led to an unsightly step appearing on most of the cars where the nose met with the chassis, which also had some interesting aerodynamic ramifications. Sauber had figured it could enclose ‘S’ shaped pipework within the nosecone that didn’t contravene regulations regarding a space 150mm ahead of the chassis line. The ‘S’ duct had been reborn, albeit in a slightly different guise, one which may not have been as powerful as the design first used by Ferrari but was a worthwhile inclusion due to the prevailing circumstances.

Red Bull joined the party in 2014 with its own version of the ‘S’ duct, using similarly compact pipework in the region at the front of the chassis, rather than being packed into the nose assembly as Sauber had.

It may not enjoy the same budget as its Red Bull sibling, but Toro Rosso also introduced its own version of the 'S' duct with a new nose design during that same season.

McLaren followed suit in 2015, introducing its own take on the concept, which featured two channels that fed the airflow along either side of the pitot tube stack.

Ever eager to gain an advantage over its midfield rivals, Force India was able to introduce its own version of the 'S' duct in 2015 and latterly added its innovative 'Cobra' nose solution shown here.

Ever the innovators, Toro Rosso, upped the ante in 2016, finding a way to reintroduce inlets in a more forward position, placing NACA-like ducts on the side of the nose to capture airflow

Mercedes also joined the ranks, having already done preliminary tests with a solution at the Brazilian GP in 2015. The 'S' duct solution on its W07 took advantage of the vanity panel to transport airflow to the chassis outlet

2017 saw Ferrari return to the 'S' duct game once more, as it too found a way to maintain a single cross-section for the nose whilst also creating a more forward placed inlet for air to flow into.

Mercedes continued to develop its 'S' duct solution, placing an even larger emphasis on the vanity panel to help with the transportation of airflow between the two bodies.

The Renault RS18's nose was imbued with numerous inlets on the underside to help power its 'S' duct solution.

Red Bull continues to look for ways to improve the working relationship of its 'S' duct with its surroundings and so the steeper transition of the nose and chassis on their RB15 was met with a taller 'S' duct outlet assembly. This solution also featured a very narrow slit on the forward face, injecting airflow into the flow structure created by the 'S' ducts outlet.

Late in the season the team decided to narrow the 'S' duct structure, focusing the airflow's path over the chassis.

For 2020, McLaren is the only team on the grid not to have an 'S' duct solution on its car.

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