Oscar Piastri’s impressive victory at the 2024 Azerbaijan Formula 1 Grand Prix can be attributed to several factors: McLaren’s extensive in-season upgrades, Piastri’s composed driving, support from teammate Lando Norris, and a strategic choice by Piastri to disregard his engineer’s advice against overtaking Charles Leclerc. Additionally, a subtle innovation in the car’s rear wing that teeters on the edge of legality played a role.
Some experts refer to it as a flexi-wing or mini-DRS. However, a close examination of rear-facing onboard footage from Piastri’s vehicle reveals a notable detail: the outer section of McLaren’s rear wing DRS flap raises slightly as Piastri maneuvers through Baku’s winding streets.
Initially, it’s worth explaining how this wing operates. When stationary, McLaren’s MCL38 appears completely standard—which is crucial since Formula 1 cars are inspected under these conditions.
However, once the car hits the track, the wing begins to change. Specifically, a gap appears between the main wing’s trailing edge and the leading edge of the flap. The wing can subtly flex, creating a small opening.
This gap is minimal; it’s too small for even an adult finger to fit through. Yet, it’s sufficient.
This tiny gap effectively functions like a miniature DRS. When drivers activate their drag reduction system, the wing flap fully opens, reducing drag and offering a speed boost by minimizing one source of aerodynamic drag.
The gap that McLaren has ingeniously designed opens just enough to decrease air pressure, providing the car with a slight speed enhancement similar to DRS.
While it would be misleading to assert that this wing gap is the sole factor—or even the most significant factor—in Oscar Piastri’s victory in Baku, it is important to note. The Woking-based team has rolled out a series of upgrades throughout the year, significantly enhancing their car’s speed, balance, and overall performance. This progress coincides with the development of two exceptional drivers in Piastri and Norris. Winning a race involves countless details, and the flexible mini-DRS wing is just one piece of the puzzle.
The burning question on many minds is whether this flexi-wing is, in fact, legal.
Currently, the answer leans toward “yes.” Blake Hinsey, a former performance engineer with Red Bull, commented, “If the technical regulations specify limits for rear wing deflection and this passes the tests, then it’s legal. All bodywork responds in complex ways under aerodynamic load. If McLaren has innovatively reduced drag on their rear wing, they deserve praise for their engineering.”
Formula 1 is full of details, and the most skilled engineers and designers excel at exploiting the intricate loopholes within technical regulations. This ability has led to innovations like monocoque technology, rear-engine placements, and advanced wing designs. If the rules don’t explicitly prohibit something, it remains a viable option.
For now, at least.
The absence of specific regulations does not guarantee immunity; both Formula 1 and the FIA have a history of imposing mid-season technical directives to eliminate unintended loopholes.
Prior to the 2023 Singapore race, for instance, the FIA released a directive addressing excessive flexibility in front and rear wings.
FIA Single Seater Technical Director Tim Goss elaborated at the time, stating, “For us, the crucial aspect of Article 3.2.2 is that ‘all aerodynamic components or bodywork influencing the car’s aerodynamic performance must be rigidly secured and immobile concerning their frame of reference and must utilize a uniform, solid, hard, continuous surface under all circumstances.’
“It is clear that absolute rigidity is unattainable. Thus, we have a series of load-deflection tests to determine how much elements can bend, evolving these tests to reflect what teams are pursuing on the track and establishing sensible limits.”
“We adhere to those rules while teams seek to exploit allowances regarding deflection. This is standard process. The technical directive is about ensuring that we, at the FIA, and the teams all share a unified understanding of where we draw the line on these design details.”
In essence, the FIA concluded that teams were not engaging in any outright illegal practices. Rather, they were taking advantage of loopholes that the technical directives had failed to effectively address.
Currently, McLaren’s mini-DRS wing appears to exist in this gray area. It represents an innovation that isn’t explicitly permitted, but also isn’t outright banned. The FIA is unlikely to penalize McLaren for being resourceful, but it seems probable that a technical directive will be imposed soon to regulate moveable wings like theirs. Once that happens, McLaren will only face repercussions if it continues to utilize its flexi-wing after a directive prohibiting it is issued.
Regardless of individual opinions on McLaren’s innovation, the design team deserves recognition for maintaining the sport’s technical intrigue.
.
