The Wet Roundabout and the Cut-In Car
You are driving a loaded rigid truck (about 12 tonnes) on a wet road approaching a large roundabout at 50 km/h in a 50 km/h zone. A car on your right enters the roundabout and then brakes sharply to take an exit across your path. Your following distance to the car ahead is about 1.5 seconds. Your load is not secured against lateral movement and you can feel it shift slightly on curves. Tyres are at the legal minimum tread.
1. Analyse the stopping and avoidance options as the car cuts across.
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At 50 km/h you travel about 14 m per second. On a wet road with a 12-tonne load and minimum-tread tyres, braking distance is substantially longer than for a car, and the load may shift under hard braking or swerving. The safest response is progressive, firm braking in a straight line while maintaining steering control, sounding the horn if it helps alert the other driver, and avoiding a violent swerve that could destabilise the truck or shift the load. You cannot rely on out-braking the car; you must create space and reduce speed early.
2. What does the 1.5-second gap tell you, and what should it be?
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A 1.5-second gap is too short for a heavy vehicle on a wet road. In good conditions a minimum of 2 seconds is expected; in rain and with a loaded truck, 4 seconds or more is appropriate. The short gap removed your margin and contributed to the emergency. Increase following distance in wet conditions and when loaded.
3. Identify the load and tyre issues and their effect.
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An unsecured load that shifts laterally changes the vehicle's centre of gravity and can cause a rollover or loss of control during braking or cornering; the load must be restrained before departure. Tyres at the legal minimum have reduced wet grip and longer stopping distances, so they should be replaced well before the limit for a heavy vehicle. Both issues made an already demanding situation more dangerous and should be corrected before the next trip.