the driver's handbook

Braking distance is the distance travelled by the vehicle once the
brakes have been applied.
• The braking distance increases if the road is wet, slippery,
uneven or unsealed.
• The braking distance increases when going downhill because
of the effect of gravity.
• The braking distance for heavy vehicles, including buses, is
much greater. Take extra care when changing lanes to move
in front of them.
• The braking distance increases at a greater rate than the
increase in the speed you are travelling – if your speed
doubles, your braking distance will increase by four times
(2 x 2); if your speed trebles, your braking distance will increase
by nine times (or 3 x 3). For example, if your vehicle travels
20 metres in braking to a stop from 50 km/h, at 100 km/h it
will take approximately 80 metres to come to a stop on the
same road surface (i.e. 4 x 20 metres).
When approaching a corner or bend, the driver needs to brake
to a safe speed before entering the corner or bend because the
vehicle will remain more stable and controllable when braking is
done in a straight line.
Did you know? Approximately 30% of all crashes
are rear-end ones (Don’t tailgate!)
Stopping distances
Vehicle Speed Stopping distance Stopping Distance
(km/h) dry road wet roads
(Metres) (Metres)
50 35 40
55 40 46
60 45 53
65 51 60
70 56 66
75 63 75
80 69 84
Source: page 98 Road Safety in Australia. Australian Transport Safety Bureau 2004.
The Driver’s Handbook 15