Aquaplaning is the effect of a loss of steering control caused by a film of water building between the tyre and road surface. Most drivers will, at some stage, experience this effect to varying degrees. As the tyre travels in a forward direction it relies mainly on the tread pattern to “evacuate” water from the road surface to enable a contact between its tread pattern and the road. Several factors can affect the resistance of a tyre to aquaplaning such as vehicle speed, depth of water, tyre pressures and, most importantly, the tread depth of the tyres.
A) Sinkage zone: water forms a wedge that lifts the tread – no contact B) Transition zone – partial contact C) Contact zone – the tread is in contact with the ground
Typical photos taken through a glass plate showing the effects of aquaplaning
Some tyre manufacturers have developed tyres particularly suited to wet conditions. These tyres usually have a directional tread pattern specifically designed to clear water away from the road. Think of the tyres used in Motor Racing: there is a specific tyre used for a wet track compared to a dry one. These tyres are very heavily grooved and the angle of these grooves is set to give the best wet performance possible. Obviously these tyres are impractical for everyday use on public roads but show the idea of tyres we see on sale from the manufacturers.