Wet Runway

Wet Runway is a runway surface that is covered with water or moisture to a depth of up to 3 mm (0.12 in). Beyond 3 mm, the runway is classified as contaminated. Wet runways significantly affect takeoff and landing performance, requiring adjusted calculations for V1, landing distance, and braking action.

• Landing distance on a wet runway: typically 1.15× to 1.43× the dry runway distance
• Takeoff V1 may be reduced (wet V1) to ensure the aircraft can stop within the available distance
• Braking coefficient is lower — anti-skid and autobrake become critical
• "Damp" runway (surface discoloration without measurable water) is treated as dry for performance
• Pilots should plan for longer rollout and use all available deceleration devices