FIA confirm details of clampdown on ‘flexi-floors’ from Belgian Grand Prix

Sam Cooper
The Red Bull plank of Sergio Perez. Monaco, May 2022.

The plank underneath Sergio Perez's Red Bull car. Monaco, May 2022.

The FIA have confirmed they are to monitor the stiffness of the planks under cars after some teams were accused of having ‘flexi-floors’.

FIA rules state the wooden plank which runs along the bottom of the car must have a limit of 2mm of flexibility, but there was suspicion some in the paddock had found a grey area which allowed them to hit up to 6mm of flexibility.

Mercedes’ Toto Wolff was the most vocal in his criticism of the FIA’s slowness to act, saying it should have been policed as soon the FIA had caught suspicion it was going on, but the Austrian now has his wish with the governing body set to inspect the cars more closely.

The FIA have introduced the new measures alongside rules to combat porpoising and some of them will be in place for the next race in Belgium.


All eyes on Spa as porpoising and flexi-floor TD arrives

As F1 gets set to return, a new technical directive could have a major impact on the first race back.

In a statement announcing the changes, as well as the approval of the 2026 engine regulations, the FIA said they will “re-define” the “stiffness requirements” of the plank.

The statement read: “The phenomenon of vertical oscillations (“aerodynamic porpoising”), combined with low ride heights and minimal rake, have been a noted characteristic of the new generation of Formula 1 cars, introduced in 2022, and has been discussed several times in the Technical Advisory Committee meetings. The appearance of this phenomenon raised concerns about safety and the health and wellbeing of the drivers.

“While the effect of this phenomenon has been less pronounced on some recent circuits, the FIA believe its occurrence, and the associated safety issues, will remain and potentially become even worse in the future.

“The FIA have consulted extensively with the teams and have come to a final position as follows:

“From the Belgian Grand Prix, the FIA will measure the phenomenon and expect teams to operate below a certain threshold in order for their car to be considered safe. In addition, the following measures are approved for 2022 and 2023:

“[For 2022] Central Floor Flexibility – changes to re-define the stiffness requirements of plank and skids around the thickness measurement holes.

“[For 2023] The floor edges will be raised by 15mm. The diffuser throat height will be raised, while care has been taken to avoid any impact on the teams’ designs of the mechanical components. The diffuser edge stiffness will be increased.

“An additional sensor will be mandated to monitor the phenomenon more effectively.”

Despite the FIA’s stated consultation with the teams, not everyone will be happy considering their comments before the approval.

At the start of July, Red Bull’s Christian Horner labelled suspicion of a flexi-floor as “total rubbish” and Ferrari were also reported to be one of the teams, alongside Red Bull, suspected of finding that grey area.