South Australia · The Driver's Handbook · chapter 3 · 17 min read

Alcohol, Drugs, Seatbelts & Distractions

To estimate the following distance, use the time lapse formula, which applies for any travel speed. Time Lapse Formula Allow three seconds to pass between the time when the rear of the vehicle ahead passes some stationary object, for example a signpost, and when the front of your vehicle reaches that point. To estimate that time, as the rear of the vehicle ahead passes the selected point, count... 1001, 1002, 1003 and your vehicle should not have reached that point before that time. Often you may need more than three seconds. This includes: – when the road is wet or slippery The distance a vehicle travels from the time you see an event occurring to the time the vehicle is brought to a stop is called the total stopping distance.

Total Stopping Distance = Reaction Distance + Braking Distance

when visibility is poor – if conditions are dark

Reaction distance (or thinking distance) is the distance travelled by a vehicle while the driver realises the need to brake and actually starts to physically apply the brake. For a fit and alert driver, it would average about ¾ of a second or 12 metres at 60 km/h.

when you have a heavy load If you double the speed, you double the reaction distance. – when the road is unsealed.

Did you know? Approximately a third of all crashes are rear-end ones (Don’t tailgate!) Total Stopping Distance