Tech Bite: Lotus trial new rear-wing endplate in Spain
Having had a tough year of it in 2014 owing to both an aggressive aero design and poor performance from the Renault power unit, the opening few rounds of 2015 have likely been more of a consolidation process for Lotus, with the team only making minor aerodynamic improvements to the E23 in the opening few rounds, as they continue to familiarise themselves with the Mercedes power unit.
In Spain the team tested a set of new rear-wing endplates, which feature a slot in their leading edge (see above). It's a design that many teams up and down the grid have employed for some time now, as it helps to increase the efficiency of the rear wing.
Ordinarily the wake generated by the rear-tyre increases the pressure on the outside of the endplate to the point where it can have a detrimental effect on performance. Strakes like the ones already used by Lotus (see green arrows) can be used to distribute this pressure, inducing vortices that improve performance. However, you can always find more ways to improve performance, with the leading edge slots (see yellow section) used to distribute the pressure from outside the endplate, inward. This effectively increases the aspect ratio of the surface, providing an uplift in performance to itself, the mainplane and the top flap alongside.
The moment before Maldonado's rear-wing failed, as he overtakes Verstappen on lap seven of the Spanish Grand Prix
Neither driver raced the new rear-wing endplates but Maldonado's rear-wing would become a source of frustration, leading to his retirement from the race. Whilst effecting a DRS-overtake on Max Verstappen at the end of lap seven, the Venezuelans right rear-wing endplate broke at its mounting with the floor.
Maldonado had completed the move but as the top flap snapped back into position the bodywork gave way. During his next pit stop the team forcibly removed the endplate, leaving the important upper section alongside the flaps. However, stability was compromised by the endplates loss and even though the central support saved him from an immediate retirement he succumbed later in the race.