Parents often advise children- “go slow- don’t drive fast”. We see lots of sign boards which tells you not to cross a particular speed limit. On a straight clear road when driver speeds up, others ask him to slow down. In brief, there is a general belief that driving slow is a the best way to avoid accidents. Our traffic police have interceptors on highways to catch speeding vehicles and fine them… While driving slow helps, there is another important factor, which most of us never give importance to (or may not even be aware of). It’s called Safe Braking Distance (SBD).
Safe braking distance is the minimum needed empty distance ahead, needed for the vehicle to come to complete halt without bumping into vehicles ahead, from its current speed, from the moment an emergency occurs. In other words, SBD is the distance you’ve to maintain, between your vehicle and the vehicle behind you, so that your vehicle can be safely stopped in case of emergency.
How do you measure Safe braking distance?
Primarily, SBD is a function of speed at which you’re cruising. Higher the speed, more will be the distance required to stop the car. Normally, for a decently skilled driver, on a normal road, it will take about 100 meters under normal condition to stop a car from 100 kmph (that is on a dry road. Can be twice or thrice that distance for wet road) and distance increases exponentially with increase in speed. But then, one can’t physically measure the distance while driving and will have to rely on his/her judgment to assess if the available distance is enough. Also the distance required to stop depends on dozens of parameters, detailed below.
One should maintain additional Safe braking distance if
In my opinion, maintaining safe braking distance is more important that going at slow speed. I don’t see any harm speeding if the road is straight, empty and has full visibility, provided the driver is in his full senses to anticipate any signs of trouble and can slow down in time.
While we usually maintain some distance from the vehicle in front of us, it is also critical to keep an eye on the vehicle on your tail, unless you enjoy being bumped in the back. But while we can slowdown and increase the distance between our car and vehicle ahead, it may not be possible to tell the car behind you to maintain the gap. If you suspect the distance is too close, best will be to let that car overtake and pass.
I spotted a more serious collision the next day while driving from Bangalore to Chennai, via Chittoor and Ranipet. The photo you see in this post is taken during that drive, where truck driver stopped/slowed down abruptly due to bad road and Innova rammed into it from behind. The wind shield had a severe crack but hadn’t shattered into pieces. I believe this version of Innova came with airbags (both passenger side and driver) and hope the occupants didn’t suffer any major injuries. After observing these 2 incidents and noticing that we hardly give any importance to the concept of safe braking distance, I felt like writing this post.
Your thoughts welcome.