Mercedes confirm "steps in place" to avoid wheel nut blunder repeat

Ewan Gale
Wednesday 26 May 2021 18:14 - Updated: 18:43

Mercedes chief strategist James Vowles has insisted steps are being taken by the F1 team to "mitigate" the chance of repeating the pit-stop blunder that forced Valtteri Bottas into retirement in Monaco.

Bottas' right-front wheel became locked onto the front axle after the nut cross-threaded and "machined" itself to the car, meaning the tyre compound could not be changed as mandated in F1's sporting regulations.

Explaining how events transpired, Vowles said: "The gun is an incredibly powerful gun, such that you can actually see the mechanics having to restrain themselves, holding themselves to the ground, otherwise they get rotated with it at the same time.

"It’s an impact force and what happens is the nut typically loosens in four or five impacts against it. A hammering action.

"Now, what happened is we came on slightly angled, so when the socket was now connected to the nut, it slightly angled relative to it.

"As a result of that, now instead of distributing the load across all of the nut, it was across a small section and that tore the metal clean off and in fact, all of the metal was removed from the nut.

"As a result of that, the nut was in place and we were unable to remove it. That’s a brief overview of what happened.

"Clearly, it’s a circumstance that cost Valtteri dearly and cost the team dearly and one that we are going to put steps in place to mitigate.”

Mercedes brings in heavy machinery

The severity of the matter was such the wheel was unable to be detached in the Principality.

Vowles has described the processes undertaken to remove the wheel ahead of the Azerbaijan Grand Prix.

"We did certain steps in Monaco to try and remove it, some during the pit stop, also some just afterwards," he added.

"Ultimately, we concluded that to remove that nut we were going to need some fairly heavy equipment, and specialist equipment, and that would be better done in the factory.

"More so, it allows us an opportunity to do an autopsy on it to understand really how that nut was worn and gather some clues to allow us to do a better job going forward in the future.

"As a result of that, we left the wheel on the car and packaged the car back into the truck to bring it back here directly.”