Every year a technical argument arises which dominates discussion off-track, and this year has been no different, even despite the stable regulations. In fact we’ve had a few hot topics, from McLaren’s diffuser to Z-floors, but it’s the flexible wing saga that has dominated headlines.
Red Bull team boss Christian Horner and Mercedes counterpart Toto Wolff have been locked in a battle over bendy wings, which truly bubbled to the surface after the Spanish Grand Prix.
From the on-board camera of the W12 and RB16 during the Spanish GP, it was evident how the rear wing profiles of the two cars behaved differently, with the RB16B wing tending to flex under high speed and high load. Horner countered Mercedes by highlighting how it is the front wing of the W12 that clearly flexes.
After pressure from Wolff to Nicolas Tombazis (technical manager of the FIA), the governing body will introduce more severe technical checks on June 15, just in time for the French GP. Many teams have expressed their unhappiness at this, as it will likely involve a total redesign of the structure of the compositional materials (heavily affecting the budget), to make the wings more rigid to pass the FIA’s tests.
Over the years in F1, the technical subject of flexible wings has often made a comeback, and has led to an adjustment of the rules as team engineers managed to find tricks to circumvent technical checks.
First of all, it should be noted that no team is running an illegal wing, as they have all passed the FIA’s current checks. But with a doubling of the load, they will need to make changes to pass these new tests.
The advantages of having a flexible rear wing are essentially attributable to a reduction in drag on the straights. The airfoil, flexing due to the vertical load that increases with higher speed, tends to assume a position with less incidence. Then, when you enter the deceleration phase, the downforce is reduced and the wing returns to its standard position.
The carbon material has a certain amount of memory, allowing it to return to its intended position, and on a structural level it is positive that the wings flex (although not excessively). Today’s single-seaters, at the highest levels of downforce, are calibrated to generate over 2,000kg of vertical load on the wheels, and are therefore the fastest single-seaters through the corners in history.
The technical regulations clearly establish in Article 3.8 that no aerodynamic parts, except the DRS and the front brake sockets, can move. Creating perfectly fixed aerodynamic structures is practically impossible, as no body in nature turns out to be infinitely rigid. The FIA essentially limits itself, through technical bending checks, that certain tolerance levels are not exceeded.
The main controversy arises from the fact that Red Bull, and five other teams, manage to take advantage of this, leaving the other four at a disadvantage.
The static controls the FIA use to simulate load simply cannot recreate 2,000kg of force, and are therefore tested at much lower weights with the assumption that they will deform in a linear manner, but they simply aren’t.
The FIA, however, makes use of Article 3.9.9, through which it can modify or introduce new verification tests, if there is a suspicion that some aerodynamic part of the car is not compliant with Article 3.8.
Precisely for this reason, the regulatory changes that will come into force on June 15 are not unusual. The leaders of the FIA were also lenient with the teams, giving them time until the French GP to make all the rear wings conform to the new rules.
Specifically, the rules of Articles 3.9.3 and 3.9.4 were simply tightened, where the various parameters and efforts to be applied were amplified.
In fact, from the French GP the rear wings will be subjected, during the FIA checks, to vertical forces of 100kg (+25kg compared to before), with a maximum flexion angle to always be respected of 1°.
At the extremes of the airfoil, a horizontal rearward force of 75kg will be applied, compared to 50kg. Overall, the wing must not exceed 1mm of flexion, while the previously allowed tolerance was a maximum of 3mm.
A presents a nice challenge for the technicians, especially for those teams like Red Bull who were very borderline with the old regulation. It will undoubtedly affect the teams’ budget, which remember, must respect the financial constraint imposed by the sporting regulations (budget cap).