Most drivers will have to perform an emergency braking manoeuvre at least once in their time on the road. When it happens, you want the car to stop in the shortest distance possible to avoid an accident.
Below are some of the things that can have an effect on how fast your car can stop; as well as what measures you can take to reduce your stopping distance.
An obvious factor, many people fail to realise just how much road conditions can affect the stopping distance of a vehicle. Road conditions like standing water, ice and snow can have a huge impact on your stopping distance, as any slippery surface that reduces the friction between your tyres and the road is inevitably going to have an effect on your braking.
The friction between your tyre and the road surface will affect the likelihood of skidding. A soft tyre on a coarse road will have greater friction, and more grip than a hard tyre on a slick road.
In heavy rain, aquaplaning can occur where the tyres cannot disperse the water between the tread and the road surface quickly enough, leading to a loss of control. In wintery conditions, snow can become compacted in the tyre tread which greatly reduces the effectiveness of the tyres and their grip on the road.
This can lead to sliding and stopping distances 10 times greater than on a dry road. The best defence when driving in bad weather is to keep your distance and take it slow.
Your tyres can have a huge impact on your stopping distance so it’s important to check your tyres often, especially in the winter months. Legally, tyres need to be changed when the tread depth reaches 1.6mm, but tread depth can have a huge impact on your braking distance long before you reach the minimum. Tyre treads are designed to disperse water on the road surface and if your treads are low, they are unable to do this and your vehicle is at risk of aquaplaning. As the tread reduces so does the tyre’s ability to grip the road, therefore it’s advised to change tyres before you reach this point at around 3mm.
At 30mph on a wet road, a car with brand new tyres will come to a stop in 25.9 metres. The same car travelling in the same conditions with tyres with a tread depth of just 3mm would come to a stop in 35 metres. That’s 35% further, despite the tyres still being perfectly legal. When the tyres reach the minimum of 1.6mm of tread, the stopping distance increases to 43 metres. That’s almost double the stopping distance of the new tyres!
Another thing to look out for is tyre pressure. Over or under-inflated tyres reduce the amount of contact between the tyre and the road which compromises vehicle performance, handling and safety.
Tyre quality is also an important factor. Buying premium tyres provides peace of mind that you are buying a quality product. There are plenty of tyre tests that show premium tyres are really worth the extra cost due to their high performance compared to cheaper competitors.
When travelling at 60mph, a car with premium tyres could stop as much as 16 metres shorter than a set of budget tyres. Premium tyres have other proven benefits, including increased fuel efficiency, lifespan and aquaplaning resistance.
Your stopping distance is made up of two factors. Thinking distance, which is the time that it takes your brain to process information and react, and braking distance, which is the length you travel from pressing the brake pedal to the car coming to a complete stop.
The speed you travel at is going to greatly affect your stopping distance, for example at a speed of 20 mph, you typically travel 6 metres before you make the decision to brake. With braking distance at this speed, it takes another 6 metres to come to a halt; that’s an average of 12 metres to come to a complete stop. With every 10mph above this, your thinking distance increases by 3 metres. Combine that with the braking distance and you’ve got a long way to go before stopping.
Once you reach 70mph on the motorway, your car can take an average of 75 metres to come to a stop. Combined with your thinking distance of 21 metres, that’s 96 metres, or the length of 24 cars, to come to a stop.
When travelling on faster roads, like the motorway, ensure you leave as much distance between you and other vehicles as possible and at the very least, follow the 2 second rule for safety.
Maintaining your brakes is important and can make a big difference to your stopping distance. Brake pads have a block of friction material that pushes against the brake disc when the brakes are applied. This material wears down over time, and the brake disc can become grooved – causing your brakes to overheat and lose stopping power.
Ensuring your brakes are well maintained will help to prevent the loss of stopping power which reduces your stopping distance.
Here at Roadwheel we offer a free while you wait no obligation brake check. It takes around 20 minutes for the overall check and we carry many brake pads in stock. In the unlikely event that we do not hold the correct stock for your vehicle, our dependable supply network can have the parts with us within the hour. This enables us to take care of all of your brake needs, including fitting, within a few hours of your check. Pads which are still used, despite being near the limit can cause extra wear on the disc forcing you to buy discs when you may not have needed them – so feel free to come in for as many free checks as you like.
It takes time for a driver to react to a situation and start to apply the brakes. The car carries on moving during this reaction time. The thinking distance is the distance travelled in this reaction time. The thinking distance increases if the reaction time increases. This can happen if the driver has an altered mental state such as driving under the influence of alcohol or drugs, is tired, stressed or distracted. Someone who is under the influence will have a much slower reaction and thinking time which hugely affects how quickly you can stop your vehicle in an emergency.
If you find yourself getting tired or distracted whilst driving, find somewhere safe to stop and take a break. This will help to keep you alert and safe on the roads. Remember, stopping distance = thinking distance + braking distance.
Make sure to keep your car in top form by booking in for regular services and checks to keep everything working smoothly and safely!