Welcome to The Briefing, where you can get a jumpstart on the United States Grand Prix with our guide to the key topics.

Every race weekend, we’ll speak to one of our engineers to discuss the key talking points ahead of the upcoming Grand Prix and simplify them so that you can dive straight into the action with a better idea of what to expect and what you should be looking out for.  

This week, powered by Google Cloud, Adrian Goodwin will be walking us through what we can expect from the freshly resurfaced Circuit of the Americas. Adrian will explain how this will impact us on a Sprint weekend, in which we have less practice time. We’ll also explore our options for rear wing and tyre choice.

Here’s what we’ll be working on and what you need to know…

1. A busy FP1 as the Sprint format returns

It’s been a while since we’ve had a Sprint weekend. We have just a single hour of practice before heading into Sprint Qualifying – and a lot of variables at COTA to try to understand. It’ll be a very busy hour.

With just the one practice session, the priority is tyres and set-up, without much opportunity to experiment – but we do have some upgrade parts here, most notably a new front wing. Lando and Oscar will each test both the new and the old parts in the session, and we’ll make a decision afterwards whether it will be used later in the weekend. It is, however, a second-order issue compared to the standard bits and pieces of race prep.

2. Testing out the new track surface

First thing to note is that the track has been resurfaced – but not everywhere, and not all at the same time. Some of the work, from T19 to the exit of T2, was done before the World Endurance Championship (WEC) came here at the end of August. The goal, presumably, was to get rid of some of the bumps. From studying the footage of that race, our thinking is that the track looks as bumpy as it has done historically – but not as bad as it was last year, which was very bumpy.

There’s also been further resurfacing work completed since WEC were here. We’re lacking any real information on that, which means we’re going in open-minded today. Expect the unexpected! 

Ride heights and stiffnesses were problematic last year, with Mercedes and Ferrari each seeing one of their cars disqualified for excessive wear under the car. With the new rules for 2024 opening parc fermé after the Sprint, there’s a little less risk involved – but you still need to get it right, and it’s a very big question.

Last year, the primary problem was a huge bump on the back straight. That’s now been resurfaced – but it looks like one bump has been exchanged for another, where the resurfaced track joins the old surface. Understanding this is a priority. We need to make sure we have the car in the right place and understand exactly where we are with the track resurfacing. There’s quite a lot that has changed.

To try to stop cars falling foul of track limits, there have also been some revisions made to the kerbs. Some of the concrete elements have been removed, so the cars will get onto the grass earlier. Anyone cutting the kerbs as much as last year will be on dirt rather than tarmac. It’s been done in a few corners. Something we need to understand.

3. Making the right tyre choices

Tyre choices will be interesting. Last year – which was also a Sprint – there was a split in the field. Most cars went for a two-stop strategy, but within that there was lots of variability, with some drivers taking two sets of Medium tyres into the race, and some with two Hards, and using those in different combinations.

On a standard weekend with a competitive car, we might potentially wait to see what our competitors do and then do the same to stay in bed and de-risk the choice that way – but we have only one hour of practice, and playing wait-and-see means you’re losing valuable laps when you don’t have many to begin with. In that scenario, everyone ends up sitting in the garage and you’ve wasted five minutes that you really can’t afford to waste. You have to have a bit of confidence in what you’re doing, and get on with it.

Tyre-wise, COTA is a fairly normal rear-limited circuit – but it’s also easy to kill the fronts. You can destroy any corner if you really try hard enough! The front-left has a particularly hard time. There tends to be a tailwind in the high-speed section, which means the drivers get a lot of push in the car and can overheat the front-left quite a bit. It gets a lot of use at T6 and T8 in the right-hand high and medium speed turns, and also in T16-T18. We’ll try to learn as much as we can about tyre management in the limited amount of time we have in practice.

4. High, but not maximum, downforce could be the way to go

Regarding downforce, for the length of the track, there are lots of corners at COTA, high and low speed, so we’ll be running with a high-downforce rear wing. Not maximum downforce, because we’ll need to be competitive on end-of-straight speeds. We have a choice of beam wings options that will move us up and down the efficiency scale, but this is largely a case of making sure we’re in the right ballpark with our competitors.

As a general rule, if you were chasing optimum one-lap pace at COTA, there would be a temptation to run with a little bit more downforce – but we know this isn’t a track where you can use all of that performance in the race, because in the high-speed sections, you’ll be managing the tyres, rather than pushing to the limit. It’ll be preferable to have more end-of-straight speed to attack or defend, instead of more downforce.

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