As light rain fell last Wednesday in Northamptonshire, the sound of a V6 turbo hybrid Mercedes power unit could be heard reverberating around the turns of Silverstone as McLaren’s 2024 challenger, the MCL38, roared in anger on track for the very first time on their filming day. Most teams do one early in the year – but why do they do them and what can be learned?

So what exactly is a filming day?

Teams can hold two filming days per year, where they can run a current spec car for 200km per day (up from 100km last year) on demonstration tyres and within parameters so restrictive, it prevents them from chasing performance gains.

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The teams use the days to capture content, which can be used throughout the year on social media, promotional materials and use by their partners. For example, often you’ll see the cars hit the track chased by a road car with a camera attached to a crane.

OK, that makes sense. How important are they?

The first one is usually a huge moment for any team – as it usually marks the result of months of relentless work, from the design office to manufacturing, wind tunnel and CFD testing to car build. It marks the first time the car is bolted together in its launch specification, as often teams push the limit on production to maximise design time – so some parts might arrive right at the edge.

The car build is a bit like putting together a giant Lego set without part of the instructions, as sometimes technical drawings aren’t available, so fast-moving is development. It makes what each team achieve with the initial car build process even more impressive.

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The first run of a new car usually takes place at a team’s filming day and before pre-season testing begins. McLaren opted for Silverstone for their first one, as it’s only around 90 minutes’ drive away from their factory in Woking.

By running the car on track at a filming day, it gives teams a first chance to see how the machine they had imagined on design software and tested in the wind tunnel runs in real life. Hopefully, every part works as it should – in combination with the other 1000 parts – so that when the team gets to testing, they can focus on understanding the package from a performance perspective and hopefully avoid losing time due to reliability gremlins.

Gotcha. And who is in attendance?

Alongside the mechanics and engineers you need to run the car, you’ll also usually see senior team personnel in attendance. McLaren CEO Zak Brown was in town for McLaren’s first filming day of the year, with his headphones on to stay in the loop. It was the first time new technical wizards Rob Marshall and David Sanchez have been trackside since they started their respective jobs for the team on January 1. Oscar Piastri’s manager Mark Webber was also in the garage, hooked up to comms, to watch his charge’s first laps in the 2024 challenger.

It's also a chance for more team members to attend and see the car on track – as there isn’t such pressure on guest passes. And such an event naturally lends itself to use for media opportunities. Alongside Norris and Piastri’s chat with F1, which you can find across F1 channels, the duo spoke to other broadcasters, did a podcast and Norris did a live hit into ITV daytime show This Morning.

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Why do drivers have to share a car at a filming day?

The use of only one car is dictated by the rules. The other will be built on a production schedule that has it ready to go in time for the first race – that takes place next week. That means drivers must share driving duties at a filming day, with each getting roughly the same amount of miles.

Last Wednesday, it was Lando Norris who turned the first wheel in the MCL38, with a break for lunch so the team could swap seats and get the car ready for Piastri to do the second-half of the running in the afternoon. Given it was wet in the morning – and cold enough in the afternoon that the track didn’t dry – there was very little that could be learned from the laps, other than being able to tick off a system checklist.