Hydroplaning Explained: What to Do if it Happens and How to Avoid
Hydroplaning is an issue that every motorist is likely to face at some point. Driving in the rain is tricky, and it’s very easy to lose control of your car.
What a lot of people don’t realize, though, is that the first few minutes of light rain are actually the most dangerous. Driving during a downpour is always going to be a challenge but those first few minutes of light rain are the period where your vehicle is most likely to hydroplane.
What is Hydroplaning?
Hydroplaning is the term used to describe the phenomenon where water on the road accumulates in front of your tires, faster than the weight of the car can move the water out of the way.
The water pressure causes your car to rise up so that it is floating on a thin layer of water. For a brief moment, your car loses contact with the road and it can feel like you are driving on a sheet of ice.
While your car is ‘floating’ on the water, you will not have enough traction to break or steer effectively.
What Causes Hydroplaning?
Hydroplaning is caused by three things:
- Water Depth
- Tire tread depth
The faster you are going, the easier it is to lose traction. If your tires are worn, then this will make hydroplaning more likely to occur.
Deeper water is more treacherous than shallow water. The very thin layer of water combined with oil and petrol residue found on most busy roads is enough to cause hydroplaning even when conditions don’t look particularly treacherous.
For this reason, it is important to drive carefully when the weather starts to get bad.
How to Reduce the Risk of Hydroplaning
Hydroplaning can catch people off guard, especially when the rain hasn’t been torrential. For this reason, it’s good to adopt sensible driving habits at all times.
Here are a few ways to reduce the risk of hydroplaning:
- If it has been raining, or if it the forecast says rain, give yourself a little extra time to get to your destination.
- Slow down. You are less likely to hydroplane at speeds of 35 mph or less.
- Allow twice the usual stopping distance between yourself and the car in front of you.
- Turn off cruise control.
- Try to avoid sudden braking, acceleration, and sharp turns.
- Avoid changing lanes unless it’s absolutely necessary.
- Check that your tires are properly inflated and have sufficient tread.
How to React if You Hydroplane
When hydroplaning happens, it feels like the vehicle is out of your control. It will start floating or veering in a given direction and you cannot stop it by braking or steering. Sometimes hydroplaning affects just one set of wheels, sometimes it can affect all four.
If your drive wheels are hydroplaning, then you might see that your speedometer and engine RPMs increase, but your tires are just spinning ineffectively. If your back wheels are hydroplaning then your car’s rear will skid sideways. When all four wheels are hydroplaning your car will skid in the direction it was originally going. This is usually the best case scenario.
Most people’s instinctive reaction to hydroplaning is to slam on the breaks and try to steer. Do not do this. If you panic and accidentally end up braking heavily then you may lose even more control and make the skid worse. There are exceptions to this, but in general if you are in a hydroplane-skid then the best thing to do is take your foot off the gas and wait for the car to regain traction.
Most of the time, a hydroplane skid will last for just a second or two, and then when you have control over the car again you can start steering or slowing down. If you have already slammed the brakes, then release them, and if you are driving a manual vehicle, disengage the clutch too.
What if You Are Trying to Avoid a Crash?
If you feel like you need to brake to avoid crashing, and your car has ABS, then you can brake normally. If you don’t have ABS, feather the brakes and gently steer in the direction that you would like the car to go. Make slight movements, and resist the temptation to over-steer. One common mistake that a lot of people make is over-reacting, losing control again, and over-reacting in the other direction. Staying calm and letting the hydroplaning resolve itself naturally is the safest bet.
Don’t use cruise control when the weather is wet. Cruise control is likely to overcompensate, and the time it takes for you to turn it off are precious seconds that you could have spent taking your foot off the accelerator and disengaging the clutch.
When you are driving without cruise control you should be able to instantly feel your tires make a connection with the surface of the road. Take that opportunity to regain control of the course of the car, and then assess the situation. If you feel you need to pull over and take a few deep breaths, then do so. Hydroplaning can cause quite scary situations and there is nothing wrong with needing a moment or two to recover from a near-miss.
Every year, there are more than 212,000 people injured, and 2,400 people killed in rain related crashes, according to the Federal Highway Administration. Taking some time to learn how to control your vehicle could help you to avoid becoming a statistic.
Invest in good tires for your car, and maintain them regularly. Do not drive if you are tired or impaired or if you are concerned that the weather is too treacherous. If you can avoid making a journey in wet weather, fog, or icy conditions, then do so. Avoiding unnecessary trips protects you and your family, and also leaves more space on the roads for those who do need to drive, such as emergency services.
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