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Wet-road analysis

Hydroplaning Speed Calculator

Estimate a theoretical threshold from tire pressure while keeping the many case-specific limitations explicit.

Method overview

theoretical hydroplaning speed is proportional to √(tire inflation pressure)

The worksheet provides a screening estimate using the selected published relationship. It is most useful for evaluating whether hydroplaning warrants further investigation.

Evidence to document

  • Collision-time or best-supported tire inflation pressure.
  • Water depth, drainage, rutting, and rainfall evidence.
  • Tread depth, tire design, load, and pavement texture.
  • Photographs, weather records, and physical tire-mark evidence.

Limitations

The pressure relationship is not a finding that hydroplaning occurred. Water depth, tread, load, pavement, steering, and braking conditions remain essential.

Record measurements, assumptions, units, rounding, and source material so another investigator can reproduce the result. See the methodology and validation center for verification policy and citation guidance.

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Scene weather · Wet drag adjustment · Drag factor