The FIA has announced it is introducing new measures in an attempt to combat 'porpoising' amid concerns over Formula 1 drivers' safety.
The severe bouncing of cars has been an unexpected issue following the introduction of F1's all-new design regulations for 2022, with Mercedes one of the worst impacted teams.
Lewis Hamilton has complained about the problem throughout the season, but with the bumpy Baku street circuit at last weekend's Azerbaijan GP exacerbating the issue and leaving the seven-time world champion in severe pain after the race, F1's governing body has taken action.
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The technical directive issued by the FIA ahead of this weekend's Canadian GP will force teams struggling with bouncing to alter the setup of their car to protect their drivers, with a limit on the level of "vertical oscillations" being introduced.
The FIA did not confirm whether the rules would be implemented in Montreal, with the announcement made little more than 24 hours before Friday's opening practice session at the ninth Grand Prix of the season.
The FIA statement said: "Following the eighth round of this year's FIA Formula One World Championship, during which the phenomenon of aerodynamic oscillations ("porpoising") of the new generation of Formula 1 cars, and the effect of this during and after the race on the physical condition of the drivers was once again visible, the FIA, as the governing body of the sport, has decided that, in the interests of the safety, it is necessary to intervene to require that the teams make the necessary adjustments to reduce or to eliminate this phenomenon."
The FIA added that it would also begin an investigation - in consultation with teams - as to how to reduce porpoising in the "medium term".
It was also explained the decision was influenced by concerns over the pain and distraction caused by porpoising potentially distracting drivers and causing high-speed crashes.
Hamilton, along with Mercedes team-mate George Russell and team principal Toto Wolff, had been speaking of safety concerns since the early stages of the season, but with more cars suffering in Baku, almost universal support came from around the paddock.
Several other drivers spoke out, with McLaren's Daniel Ricciardo insisting he was ready to help push through changes to protect his rivals.
However, Red Bull team principal Christian Horner questioned the authenticity of Mercedes' complaints in Baku, claiming the Silver Arrows were trying to force a change in regulations that would help them close the gap on their rivals following a hugely disappointing start to the campaign.
Mercedes have failed to compete with the pace of Red Bull and Ferrari, with bouncing issues repeatedly hampering the eight-time reigning constructors' champions.
'No short-term help for Mercedes'
Sky Sports News' Craig Slater explained the short-term rule changes are unlikely to improve Mercedes' performance.
Hamilton has failed to finish on the podium since the opening race of the season, and is already 88 points behind world championship leader Max Verstappen.
"I don't think this helps, in the short-term, Lewis Hamilton at all," Slater said.
"What they're saying is that you must not allow your car to vibrate like this.
"Teams that don't have a problem with it won't have to make any changes. Teams like Mercedes, whose car bounces up and down, are effectively going to have to raise the height of the car, that will stop the bouncing and it will also slow the car down.
"So, actually, in the shorter term this doesn't look like it's going to help Lewis Hamilton or Mercedes at all."
Russell: It's good for everyone
Despite the consensus in the paddock being that Mercedes will suffer from the new rules, Russell praised the governing body for taking swift action.
"I think this is something that everybody thinks Mercedes is sort of pushing for, but from a pure performance side of things... we don't really want change because if there's change, you never know if it's going in your favour or against you," Russell told Sky Sports.
"I think it's something that we as drivers have spoken about globally, that we want change moving forward because what we went through last weekend just wasn't sustainable.
"It doesn't matter what boat you're in, you're either porpoising and you're hitting the ground, or you have no porpoising so you're running the car really close to the ground and you're bottoming, so either way you look at it, it's not great.
"I think it's promising to see that they've taken action on this straight away and it's not taken them weeks and months and political decisions to change something like this. When it comes to safety, things need to be resolved as soon as possible, so I'm not surprised to see it come in so quickly but I think it's good for everyone."