Expressway overtake before a lorry overtaking ban
You drive a 7.5 t category C1 box lorry on the two-lane carriageway of an expressway (S road) in Poland. The speed limiter is set to 90 km/h and you are travelling at 84 km/h. Ahead, two lorries are in the right lane at about 68 km/h and 62 km/h; the left lane is clear for roughly 500 m. Rain has stopped but the surface is wet. A blue sign with a lorry overtaking ban (B-25a) begins 300 m ahead and continues for 4 km. Your satnav shows an exit in 1.2 km. The load is 3.8 t, tyre tread is 6 mm, and the ABS warning lamp is off. The second lorry brakes intermittently. You need to decide whether to overtake, what speed to use, and how to handle the approaching exit.
1. Should you begin an overtake before the B-25a sign? Show the time and distance reasoning.
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No. Your vehicle is over 3.5 t, so the expressway limit is 80 km/h; at 84 km/h you are already above it. The ban starts in 300 m. At 84 km/h that is about 12.9 s, and your closing speed on the 68 km/h lorry is only 16 km/h (4.4 m/s). You would need many seconds simply to draw alongside, then more to pass and return to the right lane. You cannot complete the manoeuvre and be back before the sign, and after the sign lorry overtaking is prohibited. The wet surface and the intermittent braking of the second lorry make a late return even riskier. Stay in the right lane and abandon the overtake.
2. What speed and lane position should you adopt, and how much gap should you keep?
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Reduce to no more than 80 km/h and preferably a little below it, because the road is wet and the lead lorries are braking unpredictably. Keep to the right lane; the left lane is only for overtaking. At 80 km/h on a wet road, total stopping distance is roughly 80–100 m, so a four-second gap of about 90 m is a sensible minimum, more if spray reduces visibility. Do not use the 90 km/h limiter setting as a target. If you intend to take the exit in 1.2 km, plan the lane change early and avoid being trapped alongside another lorry when the exit lane begins.
3. The second lorry brakes sharply. What is the correct immediate response?
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Brake firmly and progressively in a straight line, keep the steering steady, and let the ABS work if it activates. Do not swerve into the left lane without checking, because another vehicle may already be there. Maintain the enlarged gap to the lorry ahead; if the lorry stops, stop behind it with enough space to steer out if necessary. After the incident, re-establish a larger following distance, because the lead lorry has demonstrated unstable speed. If you are already alongside or committed to an exit lane, follow the lane markings and do not cut across a solid line or chevron area.