Following Distance on a Wet Mountain Road
You are driving a loaded pickup from Kingston to Port Maria on a winding two-lane road through St. Mary. It is 4:15 p.m., heavy rain has been falling for 20 minutes, and the posted limit is 50 km/h. The asphalt is wet, with leaves and a thin film of mud on the bends. Ahead of you is a tipper truck carrying gravel; its rear lights are dim and it has no mud flaps. You are 12 metres behind it, travelling at 45 km/h, and you are already late for a family event. Visibility is about 40 metres, and the road has no hard shoulder - only a steep drop on your left and a rock face on your right. Oncoming traffic is sparse but fast.
1. Using the conditions, justify a safe following distance and speed. Give a practical method.
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At 45 km/h you travel about 12.5 metres every second, so a 12-metre gap is under one second - far too close even in dry weather. In rain, with mud and leaves, on a loaded pickup, use at least four seconds, which is about 50 metres at that speed, and more if visibility is only 40 metres. The better rule is to reduce speed until you can stop within the distance you can see. Wet braking distance is much longer than dry, and the gravel truck can shed stones or stop suddenly. Pick a fixed object, count 'one thousand and one' as the truck passes it, and check that you reach it no sooner than four seconds later.
2. You reach a short straight with a clear view of oncoming traffic. Should you overtake? Explain the decision.
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Do not overtake. A short straight is not enough when the surface is wet, the truck is throwing spray, visibility is 40 metres and there is no hard shoulder. In left-hand traffic you would overtake on the right, but you would need a clear view, a broken line permitting it and enough space to abort. The truck may also slow for a hidden pothole or oncoming vehicle. The safe choice is to drop back, keep four seconds, and wait for a genuinely clear straight with good visibility and road markings.
3. The truck's brake lights flicker and it slows suddenly. What sequence of actions should you take?
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Ease off the accelerator, then brake firmly but progressively; do not stamp on the pedal or swerve into the oncoming lane. Keep the wheels straight and leave room ahead. If the truck stops, stop behind it with hazard lights on to warn traffic. If you feel a skid, ease the brake slightly and steer where you want the front of the car to go, without harsh correction. Do not overtake a braking truck on a blind bend.