Mercedes explain decision to stick with Hamilton's set-up for US GP

Mercedes technical director James Allison has provided insight into why the team opted not to make changes to Lewis Hamilton's car for the United States Grand Prix, despite the Briton's lowly P19 qualifying result.

Following a disappointing first-round exit in qualifying at The Circuit of the Americas, Hamilton floated the idea that Mercedes could make wholesale set-up changes to his car, which implied an exit from parc fermé and a mandatory pitlane start.

However, the Brackely squad ultimately decided against such a scenario. But it did choose to overhaul George Russell’s W15 following the latter’s crash in qualifying, imposing a pitlane start on the Briton.

Allison clarified why there was no valid technical reason that justified a similar approach fro Hamilton.

“It was an option to do what George did, to start from the pit lane having changed the set-up on his car between qualifying and the race,” Allison explained in Mercedes’ post-race video debrief.

“But we didn’t actually have any reason to think there was much wrong with Lewis’ set-up.

“He had his best bodywork on, he had the grid position we had, which is further up the road than starting from the pit lane.

“So why not start where you’d qualified even if it wasn’t the place you wished you’d qualified? So that was uppermost in our mind with respect to set-up changes.”

• Read also: Hamilton suspects Mercedes upgrades to blame for US GP demise

After qualifying, Hamilton also alluded to a potential power unit change on his car. But again, Mercedes dismissed the initiative, due to financial implications related to F1’s cost cap regulations.

“If you do put another engine in here, you go to the back of the grid, [then] because of the grid place penalty start from the pit lane,” he said. “We could have priced that in.

“But more significantly, you don’t get to just put another engine in and not pay for it financially. If your engine breaks because it’s got a problem, then the way the rules are written is that you can have another power unit at that point and it not impact your cost cap.

"But if you just say ‘I want one because I want one’, that’s a different matter. You have to pay for it.

“That would not have been a good trade. The freshness of a new power unit would have lifted your lap times fractionally, but the cost in cost cap hit would have not paid that worth back.”

Hamilton’s struggles over the weekend were compounded by an issue in the sprint race, where he experienced handling difficulties that Allison later traced to a technical fault.
Hamilton reported hearing a “clicking” noise in the front-right corner of his car as he prepared for the sprint, and Mercedes’ investigation revealed a problem with a bearing in the suspension.

“Anyone who watched it on telly would have heard Lewis saying ‘I can feel it clicking’ as he got ready for the sprint race,” Allison revealed.

“When we stripped the car after the sprint race, a race in which he struggled to get the car’s handling to be sweet-natured, we found that one of the bearings that holds one of the wishbones on had started to break up.”

The malfunction caused the front suspension to move unexpectedly, leading to inconsistent handling that Hamilton struggled to manage during the sprint race. Although the issue originated at the front end, it resulted in a loose and unpredictable feeling at the rear of the car.

“That was making it move around and giving him that clicking noise, which also was associated with a bunch of inconsistency of handling, which is the main reason why he was feeling the back end of the car – even though it’s a front end problem, it translates to the car feeling loose and unpredictable, and that had an impact on his race in the sprint race,” Allison added.

The bearing issue was addressed before qualifying, but Hamilton’s difficulties continued, leading to his unexpected elimination in Q1. Allison reassured that the initial problem was resolved in time for qualifying.

“We replaced that part and that problem didn’t re-emerge,” he stated. “So it was a pain for us to have suffered that problem. Difficult for Lewis to then have the sprint race that way, but that particular thing was put to bed by quali and didn’t feature thereafter.”

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