The influences of Mercedes on McLaren's 2021 challenger

Orange you glad it's launch season? To kick the 2021 Formula 1 season off, McLaren has pulled the robes off its papaya-draped MCL35M to begin the chain of unveilings due over the coming weeks. With it, the team has yielded the first clues to how each outfit will contend with improving last year's models for a new season.

Fittingly, it's the Woking team that had the most to do over the previous months in preparation for 2021. The second "M" in its chassis designation, of course, refers to the team's remarriage to Mercedes for its powertrain following dalliances with Honda and Renault, and so the chassis has had to be reworked to reflect that change. After all, one does not drop in an F1 powertrain at the last minute; every single component is one with the rest of the package.

But there's more to the McLaren launch than simply assessing the knock-on changes of reacquainting itself with Mercedes; it also provides the first proper glimpse of a 2021-spec floor following the updated rules mandating a back-and-sides trim. That, and a first look at the incoming Daniel Ricciardo in McLaren garb, but sartorial changes are rarely the object of these technical features.

That said, McLaren has added an extra splash of blue to the nosecone - somewhat fitting for a Monday launch.

One caveat of launch season is that it takes a very brave team to put all of its cards on the table before Bahrain. After all, F1 is arguably analogous to poker at 200mph, and there will undoubtedly be some new developments firmly kept up the design team's sleeves. Regardless, it would be remiss not to dissect those new changes.

On the tech front, if you'll pardon the pun, the nose cone has been carried over from the late-season version that McLaren trialled in the latter half of 2020. This was part of a raft of changes to the original MCL35 that took time to bed in, but eventually proved their collective worth to help the tangerine team cement a lucrative third place in the constructors' championship. This nose, based on developments by the Mercedes squad, deletes the thumb-tip crash structure and instead moves the mounting pylons underneath.

In that, it's a game of compromise. Although the thumb-tip design means that teams can fire cleaner air closer to the centreline of the car, owing to the greater open space between the tip and the mounting pylons, shuffling everything further inboard creates more space for the cape - that sweeping piece of bodywork flowing from the nosecone - to work.

As the exposed tips on the front wing create a vortex (as air wants to go from the high-pressure top surface to the low-pressure bottom surface) which is commonly used to direct any turbulence from the wheels away from the floor, the cape can interact with that to help steer it into the places needed. A bigger cape exercises more control, and the thinner nose also reduces any blockage further down the car. So, the nose remains firmly in joint.

Some concessions have had to be made to fit Brixworth's finest into the back, with perhaps the most obvious the change to the air intake, which much more closely resembles that of the works Mercedes team

There are few changes to the front part of the car shown - indeed, major changes to the front crash structure and chassis require the introduced development tokens to produce. Teams were limited to two, and the FIA's technical regulations addressed which parts required tokens to be spent, and also the quantity too. McLaren needed to put all of its tokens into one basket and focus them on the rear part of the chassis to fit the Mercedes powerplant.

Last year's front wing and T-wing are also shown and, although we don't expect wholesale changes in these areas, aero development is largely free - as long as it doesn't cross-pollinate with the areas requiring tokens. There's a collection of interesting little tweaks here and there too; the mirror mountings have been straightened up a little to help place the airflow to where it's needed. Aerodynamicists would rather not have to equip the car with mirrors, but given the risk of seven years' bad luck is enforced by the rules, they are forced to equip their reflectors with deflectors to minimise the aero damage.

To fit Brixworth's finest into the back, some concessions have had to be made. Perhaps the most obvious is the change to the air intake, which much more closely resembles that of the works Mercedes team - with McLaren ditching the Darth Vader facsimile present on the previous iteration of the car. After all, each power unit has different cooling demands, and the engines need a certain amount of air passing through the car and feeding each component.

The internals are also arranged differently, and one area that the Mercedes-powered cars all had in common last season was some variation of the sloping sidepods where airflow passing over the top could drop down freely onto the floor. That's a legacy of the interesting modern interplay between the engine design team and the aerodynamicists, and McLaren has drifted towards that here. It's not as noticeable as perhaps last years' Racing Point and Williams designs, but there is that drop-off to help feed the top of the floor with some lovely higher-pressure air to increase the pressure difference between that and the diffuser.

After all, the pressure difference is the key precursor to making downforce and, with the diffuser now less effective having had 50mm lopped away from the internal fences, any help it can get to retain that pressure difference is going to be vital. Last year's McLaren sidepods did it to a lesser extent, but it seems that the design team has been able to go further with creating that effect this time around. Of course, as the Mercedes has had to be shoved into a design concept that wasn't entirely designed with it in mind, there's a few extra bulges here and there around the sidepods - but, helpfully, the rear-end undercut is preserved to extend that floor space.

While we speak of that devil, the aforementioned trim to the floor spans a triangular exclusion zone from the back of the driver's headrest and a point forward of the rear axle. In the culling, various tools that teams employed on the floor were waylaid by the rules - including the profligacy of cuts and slots along the edge. With those gone, the floor is a lot less protected as it is less able to create a seal, with the overarching idea to limit the effectiveness of the diffuser.

PLUS: What you need to know about F1 2021

Throughout 2020's later-season practice sessions, a handful of teams bolted on a 2021-style floor to get to grips with the changes and work their magic. McLaren's launch-spec car shows the new rules in...well, not so much action, but provides the clearest idea of how the teams will approach them. The lip towards the front of the floor remains, as the little expansion of airflow acts like a mini-diffuser as airflow drifts outwards and adds a sprinkling of mid-section downforce. Towards the rear, however, McLaren has added a further small cut-out with an upright fin.

Whether this is just a placeholder design is currently uncertain, and teams were experimenting in practice sessions with curls and inward-facing fins to perhaps divert airflow inwards and use it to seal the diffuser to preserve its effectiveness. But there's little precedent with the new rules and, with apologies to those hoping for a quick take on the matter, we'll have to wait and see what the others do to build up a full picture of their effect.

The bargeboard package looks as it did on the original MCL35, and the rapid growth and complexity in this area now resembles a collection of mutant fighter planes. What it lacks is the late-season updates that McLaren employed, including the Venetian blind-style additions present last year, so it's not outside the bounds of possibility that, again, these remain a placeholder.

At the rear, the endplates have also received a bit of attention. Since the specifications of the rear wing were changed in 2017 and the endplates began to flare outwards, teams have employed the overhanging strakes around the central part to help pick up the turbulence from the rear wheels and divert it outwards, increasing the effective volume of the diffuser. In other words, because the diffuser has more space to expand airflow into, the downforce increases.

Now, McLaren has opted for the curved slot endplate design that Red Bull adopted last season, which in turn was pioneered by Haas back in 2019. It'll be interesting to understand the team's reasoning for that change, but it's certainly a more elegant solution than the profusion of strakes that we've seen in recent years.

The car looks to be a sensible development of its strong 2020 package, and the team has sought to get the most bang for its buck with its application of token changes to fit the multiple title-winning Mercedes power unit in the back

Perhaps, with the estimated 10% downforce reduction targeted by the new rules, these new endplates are a more effective way of recouping that from the diffuser and rear wing combination. That diffuser has been very cleverly concealed, so we can only speculate what McLaren has in reserve - maybe some kind of gateway to an alternative dimension, or simply a miniature black hole in lieu of a diffuser. Answers on a postcard, please.

Regardless of what McLaren's hiding in its launch spec MCL35M, there's lots to be excited about. The car looks to be a sensible development of its strong 2020 package, and the team has sought to get the most bang for its buck with its application of token changes to fit the multiple title-winning Mercedes power unit in the back.

The aim for McLaren this season is not to battle tooth-and-nail for third, but to put pressure on Red Bull in a bid to challenge for second overall. Failing that, the aspiration to be streets ahead of the other midfield runners must be a given.

However, since McLaren's rivals last year have also strengthened, that's easier said than done...