Blowing sand and a damaged tail lamp on the desert road
At 06:10 you are driving a small van on the Cairo–Alexandria desert road. Visibility is about 300 m in clear air, but you enter a patch of blowing sand and fog; it drops to about 50 m. The speed limit is 100 km/h and you are doing 85 km/h. Ahead, a heavy lorry is doing 55–60 km/h with its left tail lamp not working; its rear reflectors are dusty. You have been driving for 2.5 hours, last stopped 90 minutes ago, and have a mild headache. Your front fog lamps and rear fog lamp work. The road is straight, the surface is dry, and traffic is light but fast-moving. Your mobile phone is in a holder.
1. Which lights, speed and following gap would you choose in the reduced visibility?
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Use low beam plus the front fog lamps; high beam reflects off the sand and fog and makes visibility worse. The rear fog lamp is for making you visible from behind when visibility is seriously reduced, but switch it off when conditions improve so it does not dazzle or mask your brake lights. At 50 m visibility, 85 km/h is too fast: you need to be able to stop within the distance you can see to be clear, so reduce to roughly 40–50 km/h and be prepared to go lower. Increase the gap to at least four seconds, not two. Do not use hazard lights as a substitute for driving at a safe speed; they can mask your indicators. If the sand thickens so that you cannot see a safe stopping distance, leave the road at the next safe place.
2. How do you handle the lorry with one failed tail lamp?
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Treat it as a slow-moving hazard with reduced rear lighting. Stay well back so you have time to see its dusty reflectors and the one working lamp, and do not tailgate to 'use' its lights. Do not overtake unless you can see far enough ahead to complete the manoeuvre and return to the lane with a safe gap; in 50 m visibility that is unlikely. If you do overtake, use your indicators early, check your blind spot, and expect the lorry to move slightly because the driver may be struggling to see. If conditions worsen, drop back further or stop at a safe place rather than committing to an overtake.
3. At what point should you stop, and how would you secure the vehicle?
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Stop when you can no longer see far enough to stop safely, when the sand is causing you to lose the lane, or when fatigue and headache make your driving unreliable. Leave at a proper exit or lay-by, not on a blind shoulder, and avoid stopping just over a crest or on a curve. Pull as far off the carriageway as possible, switch on hazard lights and parking lights, put out the warning triangle behind the vehicle if it is safe to do so, and keep everyone away from the traffic side. Do not stand between the vehicle and oncoming traffic. Call for help and wait for conditions to improve rather than pressing on.