A Driver’s Guide to Aquaplaning – How to React Safely
Author: Bianca Leppert
As a result of global warming, heavy rain occurs more frequently than ever. As a result, drivers have to face aquaplaning more often. What causes it and how to get through aquaplaning safely.
Extreme weather has become common in Western and Central Europe. Climate researchers predict that climate change will lead to an increase in such incidents. The more the atmosphere warms up, the more humidity it can absorb. This in turn leads to higher levels of rainfall.
This will also have an impact on road safety. Aquaplaning often occurs during heavy thunderstorms and heavy downpours. It feels like driving on ice, something many people have experienced. But exactly what does aquaplaning mean? “A wedge of water forms between the road surface and the tires,” Christian Koch, DEKRA expert for accident analysis and tires and wheels, explains. “If the road surface is only damp, the water is sufficiently displaced by the tire. In puddles and heavy rain, however, a thicker layer of water forms between the tire and the road surface. If the tire does not manage to displace the water, contact between the tire and the road is lost.”
What happens in the event of aquaplaning?
The consequence: steering or braking forces are no longer transmitted. “Aquaplaning usually occurs on the front axis,” says Koch.“ This is where the danger is greatest, because it enters the puddle first.” The driver experiences a feeling of powerlessness. Due to the lack of connection to the road, assistance systems such as the anti-lock braking system (ABS) or the electronic stability program (ESP) no longer help. Even professionals like Formula 1 safety car driver Bernd Mayländer are familiar with these situations. “The vehicle feels lighter, you lose grip and the steering seems to go very easily, yet nothing actually moves,” he describes the experience behind the wheel. Once he even experienced it during a safety car phase at the Grand Prix of China, in which he had to drive through a large puddle on the racetrack.
For everyday driving, there are several factors to consider. Firstly, the tire tread depth should be checked regularly. Expert Christian Koch states: “This is crucial when it comes to how much water the tire can absorb. The volume is lower if the tire is driven down to the legal minimum tread depth. We strongly advise against this.”
Koch recommends no less than 3 millimeters tread depth. Anyone driving around 10,000 kilometers a year should do this check annually - for example at the time of a tire change. In addition, observing the road conditions can also be helpful. “The more modest the road conditions, the more likely local puddles are to form,” says Koch. According to the accident analyst, speed is also an influencing factor. At speeds above 80 km/h, things start to feel precarious - not even new tires can solve things then.
Top tips: What to do in case of aquaplaning
If aquaplaning does occur, there are a few tips to follow. “In general, you shouldn't make any sudden movements and act with a lot of sensitivity,” says safety car driver Mayländer. “My advice is to carefully step off the gas. If you reduce the speed too much too quickly, it affects the balance of the vehicle. Hard steering movements or hard braking are also not helpful. It is important to keep your eyes on the road. I have my eyes on the road and then steer where I want to go. But gently.” DEKRA expert Christian Koch also recommends using the clutch or selecting level N on the automatic transmission. “That way no more power is transferred. Shifting down a gear in the automatic transmission, for example, can be enough to make the car turn,” he says.
That's a lot to think about in such a high-stress situation. Moreover, visibility is also limited, and the windshield wipers are running at full speed. The good news is that the puddle will eventually end and the tires will have grip again. Even if you can't prepare for every situation, it helps to complete a driver training course. “The first reaction is very important in dangerous situations,” says Mayländer. “And in driver training, one of the things you practise is precisely this reaction speed.”