FIA director of single seaters Nikolas Tombazis revealed “four or five” teams needed to take action to comply with the new wing guidelines put in place in China.

The FIA introduced a new, stricter technical directive limiting the amount of rear wing flexibility when vertical load was applied, going down from 2mm to 0.5mm, with 0.25mm tolerance offered for the Chinese Grand Prix.

FIA confirm ‘four or five’ teams needed rear wing changes after Chinese GP TD

While some teams had claimed there were no changes that needed to be made to their cars in the days between Australia and China, Alpine and Haas did confirm they needed to make minor tweaks to their rear wings to ensure compliance with the new tests.

Others chose to keep counsel on their rear wings while some, like McLaren and Red Bull, claimed they did not need to make adjustments to their cars to comply with the new regulations.

Tombazis, however, explained that while the teams passed the tests in place in Australia, almost half the grid would have needed to act to ensure compliance for the new China rules.

“Some teams were already okay with the new compliance tests in Australia [but] I think four or five were not and had to take some action and we tested them all,” Tombazis told reporters in China, as quoted by The Race.

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“We saw quite a clear correlation between the deflection measured by the FIA test and what we saw with the cameras on board. So the teams that were exhibiting a large amount of that phenomenon, what we measured in Australia, would not comply with [in China].

“They passed the tests of Australia and so on, but they wouldn’t have passed this test if they hadn’t taken action again.

When asked about McLaren specifically and their assurance they did not need to adjust their rear wing for China, Tombazis was unsure that was the case, though did not address them directly.

He replied: “I don’t remember the exact number of McLaren, and I don’t want to talk about teams but I’m not sure if it was 0.75mm.”

The 0.25mm tolerance the FIA allowed for flexibility at the Chinese Grand Prix is set to be removed at the next race in Japan, meaning the teams will have to comply with even stricter tests from Suzuka onwards.

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