Everybody has to learn about stopping distances before they take their drivers test to get their license, but how many drivers on the road can actually remember what they are?
Stopping distances are a combination of two things:
• The thinking distance – the length of road travelled from when you see something which will need you to stop and actually hitting the brake pedal
• The braking distance – the amount of road travelled from first applying the brakes to actually coming to a stop
Both of these things can be affected by a variety of outside influences and circumstances, all of which need to be taken into consideration when calculating the safest stopping distance and therefore the space you should leave between your vehicle and the vehicle in front of you.
Thinking Distance
Many factors can affect this, not just the speed at which the car is travelling.
• Tiredness / alertness
• Alcohol
• Drugs – legal and illegal drugs can have an influence
• Age – older drivers may have slower reactions which means a longer thinking distance is needed
• Distractions – like switching channels on the radio or fiddling with a cell phone
• Impaired vision – this can increase the reaction distance needed
Braking Distance
This can also be affected by many different factors, as well of course as the speed at which the car is travelling.
• The weight of the car
• The condition of the tires – the braking distance will be increased when tires are worn, particularly in wet weather
• The brakes – the condition of the brakes obviously has a big influence on the amount of stopping distance needed. Worn brake pads and discs will both mean that the car will need longer to stop
• Road conditions – it will always take longer to stop when the roads are icy or wet . . . so remember to take this into account when driving
• Road surface – the condition of the surface of the road and the quality of the road maintenance can also affect stopping distances. If a road is covered with gravel, mud or dirt the stopping distance will be increased
So how far does it take you to stop, what distance should you allow when driving along the road at different speeds?
Here’s a list to give you some idea, notice how much the stopping distances increase as you drive faster, it can be quite surprising. You should also remember that these distances are calculated for driving along in a well maintained car in good weather and road conditions so need to be increased if any of these factors are to be taken into account.
20 mph – The thinking distance when driving at 20 mph is 20 feet, the braking distance is about the same which gives a grand total of 40 feet stopping distance.
30 mph – When driving at 30 mph you will need 30 feet worth of thinking distance but 45 feet of braking distance, a sharp rise to 75 feet stopping distance.
50 mph – The faster you drive the more the stopping distances rise. When travelling at 50 mph you will need 50 feet of thinking distance yet 125 feet of braking distance . . . a total of 175 feet.
70 mph – Although the thinking distance remains pretty constant (you will need 70 feet of thinking distance at 70 mph) the braking distance increases to a whopping 245 feet . . . 315 feet in total.
It is essential that you give yourself the relevant amount of stopping distance to the speed at which you are travelling. At Nissan Montclair they’ve got some great cars with superb brakes, but you still need to heed the stopping distances. Check out the choices at Metro Nissan Redlands.