Blowing sand and a slow convoy near Haima
You are driving a loaded articulated tanker, gross 40 t, on a two-lane desert road near Haima shortly before sunset. The posted limit is 100 km/h and your company limit is 80 km/h. Visibility is 500 m until you enter a patch of blowing sand; it drops suddenly to about 60 m. Wind is gusting across the road at 40 km/h and sand is drifting over the centre line. Ahead, three trucks are moving at about 40 km/h; the rearmost one has no working tail lights. Several oncoming pickups are using front fog lights and one is straddling the centre line. You are 50 m behind the slowest truck. Your tanker is fitted with an exhaust brake and ABS, and the tyres are at normal pressure.
1. Identify the key hazards and decide what speed and following distance are appropriate.
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The main hazards are the sudden loss of visibility, drifting sand reducing grip, the unlit truck ahead, oncoming vehicles encroaching on your lane, and the heavy tanker's long stopping distance. At 80 km/h you need well over 60 m to stop even on dry tarmac; in sand, braking distance increases and steering grip is reduced. Because you can see only about 60 m, 80 km/h is too fast. Reduce speed immediately to a level from which you can stop within the visible distance, probably around 30–40 km/h, and increase the gap to the truck ahead to at least four seconds or 80–100 m. Do not overtake: you cannot see far enough to complete the manoeuvre safely, and an oncoming pickup may already be in your lane. Use low beam, not high beam, because high beam reflects off the sand.
2. Should you continue, stop on the shoulder, or leave the road? Explain your decision.
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Continue only while you can see enough to stop safely and stay in your lane. If visibility falls further, or if the unlit truck and oncoming traffic make the situation unpredictable, stop. Do not stop in the traffic lane. Signal early, slow gradually, and pull fully off the carriageway onto firm ground, preferably at a known layby or wide shoulder rather than into soft drifting sand where the tanker could bog down. Switch on hazard lights and side lights; if visibility is very poor, keep them on and stay inside with seatbelts fastened unless it is safer to stand away from the vehicle. Avoid stopping just over a crest or on a blind bend where approaching drivers cannot see you. Notify dispatch of the delay and do not resume until visibility and road grip improve.
3. What vehicle checks and driving technique matter after the sandstorm passes?
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After the storm, check the air filter and radiator for sand blocking, inspect wiper blades and washer fluid, clean lights and mirrors, and check the windscreen for abrasion. Look for sand ingress around wheel hubs and brake components; avoid immediate hard braking until you have tested the brakes gently in a safe area. Check tyre pressures and inspect for cuts. When moving off, accelerate and brake smoothly because sand on the road reduces grip, and keep more space than usual. Use the exhaust brake with care on a tanker: it helps control speed but does not replace the service brakes, and on a slippery surface abrupt engine braking can cause wheel slip. Continue to expect reduced visibility in patches and do not assume the whole road is clear.