Why F1 flexi-wing changes failed to make an instant impact at Spanish GP

“It clearly slowed McLaren down a lot,” said Mercedes’ George Russell, voice freighted with sarcasm.

“So, yeah, good news.”

Ahead of this weekend’s Spanish Grand Prix the issue of aero-elasticity had acquired so much momentum that it was virtually the only show in town. To look out on the panoramic vista of the pitlane from the media centre on Friday morning was to see TV ‘talent’ industriously gesticulating at various front wings for the edification of their viewers.

Over the past few months there has been much wailing and gnashing of teeth over the matter of front and rear wings flexing for aerodynamic benefit. The FIA has progressively clamped down on this by introducing new high-definition cameras to monitor wings at speed, and tightening up the permitted tolerances.

Progressive – but not fast enough for some leading teams, most vocally Red Bull, which felt McLaren owed its apparent advantage on track to exploiting material properties for aerodynamic benefit. The deadline of the Spanish GP weekend for imposing tougher new tests on the front wings was viewed as too late by some, though the explanation for delaying it until this point – it didn’t make economic sense to make teams junk existing designs at the beginning of the season – made sense.

Those hoping the new tests would result in an instant and obvious shake-up of the running order would end the Friday of the Spanish GP weekend disappointed: McLaren topped both sessions. The sense of deflation was palpable, as responses up and down the grid ranged from “nothing to see here” to “more data required”.

“I think the car feels similar,” said Fernando Alonso. “And I think the competitiveness is similar to the last few events. “So I don't think that it did change massively.”

“On that side, I think it was very similar,” said Esteban Ocon. “It didn't make a big change or shift for us, so I think it's the same thing as usual for us.”

“If you look at the standings, not a lot,” said Max Verstappen when asked about the effects of the new technical directive. “But from my side, that was also not really expected.”

Max Verstappen, Red Bull Racing

Photo by: Red Bull Content Pool

Where do we go from here?

Verstappen, of course, has been very open – since the beginning of the season – in saying the disparity in performance between McLaren and Red Bull is a factor of his RB21’s wayward track manners rather than the MCL39’s aero-elastic properties. The narrative that McLaren has found some ‘secret sauce’ which has to be legislated out of existence has chiefly emitted from Red Bull’s management.

In truth, any aero-elasticity teams were exploiting would have had relatively subtle effects, even if the images of wings appearing to flex under load look dramatic on TV. No composite component can be infinitely stiff and a degree of flex is inevitable – the question is how much, and to what extent the property is being exploited to find a performance gain.

It is a matter of tiny degrees of movement.

With the front wing, any boost in straight-line performance by a plane flexing to reduce drag is actually a second-order effect. The chief benefit teams have been looking to find here is an improvement in balance, since the modern generation of ground-effect F1 cars tend to migrate suddenly from understeer to oversteer in certain types of corner.

Clamping down on wing stiffness was therefore likely to have a subtle effect, muddied by the fact that none of this season’s cars have run at this circuit before, so there is an absence of data enabling teams to compare directly. Also, as has been the case throughout the season, different circuits favour different teams – and Barcelona is what McLaren team principal Andrea Stella might describe as a “pears” circuit  whose layout favours Red Bull’s car.

It's therefore impossible to say definitively what effect the flexi-wing clampdown has had based on a single day’s running, whatever the gap between the leading teams. Especially since several of them introduced new wing profiles for performance reasons – not just to comply with stiffness tests – this weekend anyway.

“It's too early for us [to say what difference the tests have made],” said Ferrari team principal Frederic Vasseur. “But at the end of the day, it's not that you can expect to have big delta of lap time between the teams.”