Article C2.2
Principal Planes
Technical Regulations
Article C2.2
Principal Planes
Chapter: ARTICLE C2: CONVENTIONS AND FUNDAMENTAL DIMENSIONS
In Simple Terms
F1 cars are measured using invisible reference planes to ensure they meet size and position regulations. The main planes are a horizontal line at the bottom of the car's suspension and a vertical center line running down the middle. Additional planes mark specific locations along the car's length for measuring different components.
- Plane Z=0 is a horizontal reference at the lowest point of the car's sprung suspension
- Plane Y=0 is the vertical plane of symmetry dividing the car into left and right halves
- Multiple additional planes (XA, XC, XF, XR, XDIF, XPU, XFIS) mark specific longitudinal positions for component measurements
- These planes are used to verify compliance with dimensional and positioning requirements throughout the car
Official FIA Text
The Plane Z = 0 is defined as a horizontal plane sitting at the bottom of the sprung part of the car. The Plane Y = 0 is defined as the plane of symmetry of the car. Additional planes XA, XC, XF, XR, XDIF, XPU, and XFIS are defined for specific reference points.
principal planesreference planescar geometryz planey plane
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