Article C3.18.9
Diffuser Flexibility
Technical Regulations
Article C3.18.9
Diffuser Flexibility
Chapter: C3
In Simple Terms
The FIA tests if the floor (the bottom of the car) flexes too much during races. They push down on it with weights to make sure it stays rigid and doesn't bend more than 5mm in the main area or 7mm on the winglets. This prevents teams from cheating by making bendy floors that could gain an unfair advantage.
- Floor must not flex more than 5mm when tested with 100N downward load applied at two points
- Floor winglets have a slightly higher tolerance at 7mm maximum deflection under 60N load
- Testing uses 25mm diameter adapters with sealed holes to apply precise, controlled loads
- Excessive flexibility is considered illegal bodywork that provides performance advantages
Official FIA Text
Floor Bodywork must deflect no more than 5mm when two loads of [0, 0, -100]N applied symmetrically at Y=±320 or Y=±215. Floor Winglet bodywork must deflect no more than 7mm when 60N load applied normal to surface. Loads applied using weights through 25mm diameter adapters with holes sealed on both surfaces.
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