Will McLaren go down the Mercedes ‘rathole’?

Despite concerns there’d be 22 lookalike cars, the brief – and often blurred – glimpse into Formula 1’s new technical era has revealed cars with innovative designs up and down the grid.

From Mercedes and Ferrari’s mousehole to Aston Martin’s suspension layout and McLaren’s heavily twisted front wing, teams have found subtle but effective solutions to improve the performance of the car.

Will McLaren copy Mercedes’ ‘rathole?

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But as yet, no one knows which design, or which tiny but effective innovation, will win the title.

Last week at the Circuit de Catalunya, the teams had their first up-close look at their rivals’ all-new F1 cars as the overbody air machinery with its active aerodynamics took to the track.

One of the innovations that stood out was the mousehole on the Mercedes W17 and the Ferrari SF-26.

More analysis from PlanetF1’s technical editor Matt Somerfield

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The intent behind the hole is to enhance airflow and improve downforce by allowing some airflow from the external surfaces to switch to the diffuser’s inner wall, improving diffuser flow and downforce.

The Mercedes W17, which runs the same power unit that powers the McLaren, also has a bit of wing near that hole to increase the airflow to the hole.

Last year’s title winner McLaren does not have either the hole, nor the wing.

That intrigued former Jordan F1 technical director Gary Anderson, who noted that Mercedes especially hadn’t gone with just a mousehole, they’d enlarged it to what he termed a “rathole”.

“As the slot in the rear of the floor leading into the diffuser exit has been enlarged this year, I suppose it should now be called ‘the rathole’, and it certainly could put the cat among the pigeons in terms of performance,” he told The Race.

“Mercedes have also added what looks like a small wing section above the floor, increasing the power of that outward airflow in that area…

“As we can see, most of the other frontrunners have, to some degree, an opening in this area. They also have the secondary turning vane mounted to the inner surface of the brake duct.

“McLaren, for now, are the exception, although it could be just around the corner. If not, I’m sure we will see their interpretation of this opening in Bahrain.”

But McLaren will not be the only team taking a hard look at its rivals cars, the MCL40 and its nose cone will also have caught the attention of rivals.

According to PlanetF1.com’s Somerfield, the McLaren MCL40’s front wing and nose cone is a design unlike any other.

“Its endplate geometry is one of the more interesting solutions under the new rules,” he said. “The leading edge is heavily twisted inboard, with the rest of the span laying down to encroach on the outer flaps. This changes the airflow’s behaviour in that region and alters the wake turbulence behind the wheels.

“Regulations intend for these wings to produce more inwash, but teams aim to extract maximum performance within those constraints.

“McLaren’s wing doesn’t attempt the outwash seen on recent cars, but it shows a clear effort to manage the flowfield effectively.

“The team uses a large diveplane aligned with the endplate twist, notch, and footplate taper, while omitting vanes atop the footplate.

“The mainplane and upper flaps feature a mature geometry, with the leading edge swept upward near the endplate to expose the underbelly, and central flap loading similar to recent designs.

“These wings are designed with two states in mind: active aero on the straights for drag reduction and cornering load when deployed.

“Unlike previous generations, McLaren’s mainplane and flaps are now full-span elements, with a narrower chord in the central section. The nose is minimalist, with a slender tip and slim main body, directing airflow cleanly along the car’s centreline. The wing pillars curve from the nose to the wing body, aiding this flow.

“Active aero actuation is internal, with minimal tie rods and less airflow disruption than solutions with external pods. A small hole on the nose bridge allows manual front wing adjustments, continuing a trend among teams using internal actuation.”

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