Giorgio Piola's F1 technical analysis
Formula 1 pressed the reset button for 2017 and embraced a brand new set of technical regulations that promised wider, faster, more visually appealing cars that would push drivers to their limits.
With downforce increased dramatically and Pirelli offering substantially wider tyres, the cars not only looked more appealing but offered laptimes that were appreciably quicker too.
The drivers were subjected to lateral loads of over 5G, with apex speeds up by over 30 km/h - putting the onus on the drivers to live up to the demands of driving these machines.
With the technical regulations placing more focus on delivering more downforce, the weight of expectation fell on Red Bull's shoulders, as it was expected to take the fight to Mercedes.
Though it fell short initially, it built momentum throughout the season, often taking the best of what the others had come up with and adapting it to suit its machine.
As Red Bull faltered, another rose to the challenge, as Ferrari looked to dethrone Mercedes with an elegant but purposeful design that featured numerous novel solutions that would catapult it back toward the front of the grid.
Meanwhile, Mercedes applied its own fascinating twist.
Let us delve into the absorbing technical battle then, as we count down the most innovative solutions of 2017.
1 - Radical reveal
One of the biggest 'wow' moments of the year came when Ferrari unveiled the SF70H and it became clear it had thought long and hard about the challenge of the new rules, adopting a complex and multi-faceted solution for their sidepods that meant the car could remain relatively short.
The intent of the new regulations was not only to hand over more downforce to the teams but to make the cars look more visually appealing, with dimensional constraints placed on designers that forced deltoid shaping of the front wing, sidepod and the floor's leading edge, as well as a re-imagining of the rear wing's shape and height.
The turbulent airflow shed by the now-wider front tyre would be problematic with this new angular design constraint, and so Ferrari met these conditions in a very unique way, setting the actual sidepod back and introducing a series of flow-conditioning devices ahead of it.
This achieved the Scuderia's goals of improved cooling and aerodynamics, but also allowed a shorter wheelbase. In contrast, Mercedes was forced to lengthen its challenger in order that the front tyre wake's influence was lessened by the time it reached this critical area of the car.
The foundation of this innovation is the lateral thinking required to achieve such a solution. The design team not only had to consider the aerodynamic and cooling consequences of the concept but also the construction of it, with the side impact support spars needing to be located in a way that made the entire idea work.
Teams used to waste huge resources on designing their own impact support spars as they chased ever-more complex designs, such as McLaren's U-Pods from 2011 (lower left inset).
Since 2014, designers had been locked into a one-dimensional design construct, with the upper of the two spars straddling the frontal region of the sidepod (see W05, right inset, blue arrow) as the FIA had standardised the structures (middle inset).
To make its grandioso plan comply with the regulations, the Scuderia had to find a new home for the impact spars ahead of the sidepod and cleverly mounted them in the bodywork ahead of it (upper spar, blue arrow, main image).
2 - Major surgery
The Spanish GP is a major waypoint in the cars' development cycles; as the first European race of the season, it allows the teams to usher in large-scale update packages without the expense of traipsing them across the globe.
This gives the designers time to prepare, test and manufacture parts that can have significant lead times, potentially rectifying initial inefficiencies or unlocking previously untapped performance.
For Mercedes, this was an extremely sensitive point in its season, as its fight with Ferrari was intensifying and Red Bull was becoming a larger threat.
If the planned update didn't correlate with the performance boost shown when the aerodynamic parts were tested in CFD and the wind tunnel, it would mean a walk back that could make not only that update but also the last six to eight weeks' work irrelevant too.
One of the most sensational parts of the update package was the team's new nose, which included a novel solution that we'd not seen before and was referred to by the team as a 'cape', as it appears to drape under the nose.
The scooped device, which starts extremely far forward, reaches back to a point where it replaces the turning vanes that ordinarily reside on the underside of the nose and chassis (upper left inset).
The importance of this update shouldn't be understated either, as not only is it genuinely different from anything that has graced the grid before, but the scale of the aerodynamic surface is only matched by the team's ambition, given a new, slimmer nose structure was also needed, requiring a new crash test to be passed.
This required a bold decision in the early development phase given the lead time for such an item, meaning it was likely in the works before Mercedes arrived in Melbourne.
The technical team, directed by the former Ferrari engineer James Allison, were able to save weight with their upgrades throughout the season, bringing it down to the minimum.
It's one of the salient features that allowed Mercedes to use wings with lower angles of attack relative to Ferrari while being able to use its superior engine power to reach top speeds higher than the Red Bull, who ran even less wing.
The team continued to make smaller updates to the nose scoop in both Austria (inset, lower left) and Malaysia (inset, upper right) as it optimised its initial concept to extract more performance from it.
3 - Coincidental similarity
So prescriptive are the regulations that rarely do two teams come up with genuinely interesting and unique solutions, but that's exactly what happened in 2017, as both Mercedes and Toro Rosso designed almost identical front suspension layouts.
In fact, James Key, Toro Rosso's technical director, was shocked by the happenstance: "I looked at the Mercedes and thought: 'Ah, OK. They've got our front suspension'.
"So, on the one hand we were pleased to see someone else has done a similar thing; on the other hand we were disappointed that we weren't the only team to think of something."
Both teams opting to use an upright extension was born out of both the necessity to build in mechanical flexibility - allowing the car to be adapted if it reacted poorly to the new generation of Pirelli tyres, while offering aerodynamic advantages owing to the change in airflow around that region due to the wider tyres and improved freedom ahead of the sidepods for aerodynamic devices.
4 - Scything through the field
We've already seen how innovative the SF70H was around its midriff, but another interconnected solution drew the attention of Ferrari's rivals in the early stages of 2017, as the outer section of floor could be seen moving up and down quite violently.
The other teams suspected that Ferrari was using the effect to improve the sealing effect on the edge of the floor, pushing away the front tyres' turbulence, and lobbied the FIA to redress it.
Following several attempts to strengthen the forward-most section of the slot (white circle), the team finally relented and closed the slot, adding a metal section when it arrived in Austria.
Innovative solutions often draw attention and another Ferrari solution that occupied the space just above this floor slot was the louvred deflector panel, which was subsequently copied by Red Bull in Singapore.
Now, while the Ferrari and Red Bull deflectors may initially look like twins - even down to the use of two horizontal louvres - there is one major difference, with Red Bull opting to discard Ferrari's more blunt leading edge in favour of a leading edge slat (red arrow), likely the consequence of differing flow characteristics ahead and how they want to rework the wake created by the front tyre.
5 - Biomimicry
The teams capitalised on mistake in the redraft of the regulations which opened the door for the T-wings all the teams used during 2017.
These 50mm-deep winglets became ever more complex throughout the year and saw teams use up to three elements with slots in each and, in some cases, a lower winglet too.
It was Mercedes who struck first, when its launch car performed its shakedown at Silverstone, pairing the T-wing with its own support pillar that intersected the exhaust and mounted to the crash structure.
It latterly increased its complexity from a single element appendage to a three-tier one (above), pairing it with another novel solution - its shark fin engine cover, which featured a cooling chimney that allowed heat generated by the power unit a quick escape path.
The idea went uncopied, but when Force India introduced a new engine cover solution in Singapore it occupied a similar region. The concept, which featured over 30 paired winglets along the cover's spine, was quickly dubbed the 'Stegosaurus' fin.
It's understood the row of paired winglets worked with the larger winglet (blue arrow) added atop the airbox to create a cascading vortex that, in combination with the shark fin, improved the balance of the car in yaw and improved flow to the rear wing.
Both the shark fin and T-wing have been outlawed for 2018, and so while these extreme examples offered a performance boost last season, they're now consigned to the dustbin of history.
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