Having fallen just 2.2 seconds behind Austin race winner Max Verstappen, Mercedes racer Hamilton plus sixth-placed Leclerc were then thrown out for running with excessively worn floor planks.
They had contravened the FIA Technical Regulations which states that the plank assembly measured at designated holes can only wear by 1mm down to 9mm across a weekend.
With their rear skids deemed illegal, the standard exclusion penalty for a technical breach was applied.
The standard procedure
Post-race scrutineering is part and parcel of motorsport all the way up from a grassroots level. After an F1 contest, an array of temperatures, torques, software, fuel and component checks are carried out.
But these are not uniform across the 20 cars. The sporting regulations permit technical delegate Jo Bauer to carry out “at his discretion, any checks to verify the compliance of the cars entered in the competition”.
Accordingly, no cars had their floors checked following the Japanese GP, one was looked at after the Qatar sprint race and three cars assessed in the immediate aftermath of the full-length Qatar GP.
For Austin, four cars were reviewed. Alongside the Mercedes and Ferrari, Verstappen’s RB19 and (disqualifications applied) runner-up Lando Norris’s McLaren were checked and deemed legal.
Why Hamilton and Leclerc were caught out
The FIA can zero in on which cars to single out for further inspection based on a variety of indicators.
In the case of a worn floor, a beaten-up titanium skid plate gives off a strong smell that can arouse suspicion from the pitwall. A better read is the onboard footage, which the FIA will monitor to see if drivers’ heads are wobbling as a result of bottoming out over bumps.
Following the high-profile return of porpoising amid the adoption of ground effects for 2022, the FIA also now measures the vertical oscillations in the car to ensure the drivers are not put at risk from vibrations.
Should a car attract attention for these excessive movements, then the technical delegate will be inclined to investigate further.
Bauer is also not limited to one car per team, meaning he could have also ordered spot checks for George Russell and Carlos Sainz if there was grounds to suspect both Mercedes or both Ferraris were running too low.
That the pair were left alone suggests they did not leap out to the FIA based on their onboard camera feeds and oscillations data. It is therefore likely that Hamilton and Leclerc fell foul of the rules based on their own individual set-ups.
To wear the rear skid plate points to the W14 and SF-23 either running too low a ride height at the back axle or running too soft to allow the cars to kiss the asphalt as they rebounded from hitting a bump.
That Verstappen passed scrutineering might point to the RB19 running stiffer to lock the ride height in position to stop it from bottoming, however uncomfortable for the driver.
Notably, the Red Bulls had to lift through Eau Rouge at Spa earlier this season to avoid grounding out.
Hamilton and Leclerc being pinged in no way points to a deliberate attempt to dodge the rules.
Instead, they were caught out by the sprint format that only allows for one hour of practice before parc ferme comes into effect. From then on, teams are heavily constricted with how they may alter the car.
The limited window meant some teams did not complete heavy fuel running prior to the GP. They were therefore unable to optimise the car to navigate the Circuit of the Americas bumps, which were much worse this year despite the resurfacing of Turns 12, 14, 15 and 16.
What’s more, teams are free to remove the plank to take accurate measurements to assess wear up until parc ferme takes hold. Then they are limited to effectively highly educated guesses.
It appears to be the case that Mercedes and Ferrari simply got theirs wrong.
Perfection versus pragmatism
While the FIA can count on data relating to oscillations plus onboard footage to identify potential non-compliant cars, the potential issue is that of the 17 finishers, 13 cars were not checked for their floors.
That necessarily means there is a chance, however remote, that one or more might have finished with a plank that had illegally worn excessively. They therefore wrongly scored points, having profited further from Hamilton and Leclerc’s exclusions.
As such, the perfect scenario would be that every car undergoes a firm set of scrutineering checks. But the FIA cites practical limitations that prevents this from being the case.
Given the array of checks available to the technical delegate, if all were carried out for all cars, the process would take too long.
The US GP weekend exacerbated the problem. A sprint weekend means scrutineering is carried out after Friday qualifying, the Saturday shootout, the sprint and the full GP.
For this round, there were only 3 hours and 45 minutes from the end of the Saturday qualifying before the sprint race. That already restricted window does not account for the pre-race build-up, out-laps and grid preparation.
Then, following the GP on Sunday afternoon, every hour extra that the car might be held in parc ferme while checks for all 20 competitors are completed delays when teams can pack down and ultimately freight the car to the next race, which happens to be this weekend in Mexico as part of a rapid-fire triple-header.
In the eyes of the governing body, at some point speed must surpass absolute thoroughness.
Could the race result be appealed?
If any teams, not satisfied by the FIA’s level of monitoring, had a suspicion that a rival was running cars too low, it might reasonably want those planks to be assessed to see if further disqualifications were required to boost its result even higher.
However, there is only a 30-minute window starting immediately from the chequered flag when teams might protest the result of the race – as Aston Martin successfully did in Austria this year amid the track limits debacle to get Sainz and Hamilton, Esteban Ocon, Pierre Gasly and Alex Albon demoted.
Verstappen won the US GP in 1h35m21s (plus the time taken to complete a formation lap) following a 2pm local time start. But the technical delegate’s report on the floor checks was not issued until 5:28pm. By which time, it was already too late to protest the race result.
With the cars that were not called to scrutineering then released back to their teams as parc ferme ended, dissembling could begin. Once tampered with, it would have been impossible to recall the cars and reliably check conformity. As such, a protest of the result was not viable.
Even if the parc ferme and protest windows far longer, rival teams may have been highly reluctant to formally question the race result.
Given the sprint race format meant they hadn't been able to accurately measure their own planks since Friday afternoon, they could have potentially been unknowingly running a non-compliant cars. These, upon protest, would have been checked, identified and thrown out, too. Thus presenting a major gamble.
That protest window having closed, the only parties that can now reopen the case is Mercedes and Ferrari, should they decide to appeal the disqualifications.
However, intentional or otherwise, they breached the technical rules, for which there is no grey area to exploit to have the decisions overturned. Disqualification was inevitable.
For example, Sebastian Vettel lost a podium finish for Aston Martin in the 2021 Hungarian GP after the team could not provide the regulated one-litre fuel sample at the end of the race.
Aston Martin could, though, successfully prove that this was due to a fuel leak rather than a fuelling error, but nonetheless the exclusion was a slam-dunk case.
All told, an appeal is highly unlikely. That will leave Hamilton and Leclerc’s disqualifications to stand.
