Aquaplaning is a phenomenon that occurs when a layer of water builds up between the tyres of a car and the surface of the road. The tyres cannot grip the road properly, and the lack of traction means the driver loses control and is unable to steer, brake or accelerate.
Aquaplaning is most likely to happen when heavy rainfall builds up on the road surface. But the issue can be made worse by the condition of the car's tyres and the speed that it's travelling. For these reasons, it's important to:
- keep car tyres inflated to the correct air pressure;
- monitor tread depth so they don't fall below the legal minimum of 1.6mm;
- reduce speed in wet conditions.
Bicycles are not susceptible to aquaplaning. Whereas car tyres create a square road contact -- and have a straight leading edge with the road that makes it easier for a car to trap water under the tyre as it rolls -- bike tyres have a rounded contact with the road which pushes the water to either side of the tyre more efficiently. That's because they're designed to lean into corners.
Another key difference is that bike tyres are narrow and inflated to a relatively high air pressure. This means less water is in contact the leading edge of the tyre, and the high tyre pressure is more efficient at pushing water out from under the tyre. By comparison, car tyres are wide and inflated to a lower air pressure; this can make it difficult for water to escape from the middle of the car tyre.
Finally, there is the question of speed. A car travels much faster. Depending on the depth of water, this speed leaves less time for water to be dispersed. It's highly unlikely that a bicycle will ever travel fast enough to begin aquaplaning, no matter how furiously you pedal.