Mercedes arrived at the F1 United States Grand Prix making no secret of their upgrade and said that, as they only have one copy and potential damage would have resulted in starting at the back of the grid, they plan to debut them at the next race in Mexico.

However on Friday in Austin, Mercedes were “surprised” to learn that their new wings would not be approved in their current form by the FIA, DAZN and Auto Motor Und Sport report.

Plans for the upgrade had already been sent by Mercedes to the FIA, and were approved.

But the stabilisers are too large, according to reports ahead of Qualifying in Austin.

Lewis Hamilton and George Russell’s cars will have reduced attachments on the stabilisers for the Mexican Grand Prix in order to comply.

The overall upgrade could bring one-and-a-half tenths of lap time per driver.

• F1 2022 United States Grand Prix - Free Practice Results (2)
• F1 2022 United States Grand Prix - Free Practice Results (1)

Explaining Mercedes’ non-compliant upgrade

Sky’s Ted Kravitz said: “You are not allowed front wing furniture to direct air flow into any direction that you want. 

“What Mercedes have done with their new front wing is to say: ‘These are just front wing Slot Gap Separators that are not designed to capture air and push it outboard!’

“It looks like they are.

“This is where the questions from the other teams have come from.

“They say: ‘These are slot gap separators masquerading as airflow conditioners to push the outwash’.

“An accidental benefit?

“What the FIA cannot do is guarantee that stewards will agree when they get to the circuit.”

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