Overtaking a Slow Truck Before a Blind Crest
You are on a single-carriageway road between Benguela and Lobito. The speed limit is 90 km/h. You are behind a loaded truck doing about 45 km/h. The road ahead is straight for roughly 300 metres, then rises to a crest where you cannot see beyond. There is a solid white line on your side of the centre line for the next 150 metres. Oncoming traffic is light but a car passed you in the opposite direction about 10 seconds ago. Your vehicle is a small hatchback with four adults aboard. You have been following the truck at about 2 seconds' gap.
1. Assess whether an overtake is safe now, and justify your decision using the specific features of this road.
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No - an overtake is not safe here.\n\nReasons:\n1. Solid white line on your side means overtaking is prohibited for the next 150 m. You must not cross it.\n2. Blind crest ahead - you cannot see what is beyond the rise. A vehicle could be stopped, slow, or oncoming just over the crest.\n3. Speed differential - the truck is at 45 km/h; to pass safely with four adults aboard a small hatchback you need to accelerate to well above 45 km/h and complete the manoeuvre before the crest. At 300 m of visibility minus the 150 m solid-line zone, you have only about 150 m of usable straight - far too short to accelerate, pass, and return to your lane.\n4. Recent oncoming vehicle - the car that passed 10 seconds ago suggests traffic does use this road; more may follow.\n\nCorrect action: stay behind, maintain a safe following gap, and wait for a section with a broken centre line in your favour, clear visibility beyond the crest, and no oncoming traffic.
2. The truck is now doing 40 km/h and you are getting impatient. What following distance should you keep, and why does the 2-second gap need to change?
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Keep at least a 3–4 second gap behind this truck, and drop back further if you cannot see past it.\n\nWhy the 2-second gap is not enough here:\n- Visibility: a loaded truck blocks your view of the road ahead. A longer gap lets you see around it and gives you time to react to hazards the truck driver brakes for.\n- Stopping distance: at 90 km/h (the limit), your total stopping distance is roughly 70–90 m on dry tarmac. A 2-second gap at 90 km/h is only 50 m - less than your stopping distance if the truck brakes hard.\n- Impatience risk: following closely encourages a rushed overtake. A larger gap reduces the temptation and gives you room to build speed before pulling out.\n\nRule of thumb: if you cannot see the truck's mirrors or the road ahead of it, you are too close to consider overtaking safely.