Rain and Diesel on the Aburi Descent: Reading Warning Signs as a Sequence
It is 17:50 and raining hard on the Aburi-Accra descent. You have just passed a triangular 'Steep Hill' warning sign, then a 'Double Bend for 3 km' sign with a 'Slippery Road' plate beneath it; black-and-white chevron boards mark the outside of each curve. You are doing 50 km/h in a 50 km/h zone, in third gear, with headlights on dipped beam. Ahead, a tro-tro loaded with passengers is descending at about 30 km/h and its brake lights are flicking on and off repeatedly. At the second bend you can see a rainbow-coloured film across the wet surface where a tanker has spilled diesel. A pick-up is sitting close behind you, its headlights filling your mirrors. Your rear tyres are close to the wear indicators and the wipers are struggling in the spray.
1. Read the signs and the road together. What do the warning signs require you to change before the second bend, and why does the speed limit not settle the question?
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The signs form a sequence describing one hazard: a long descent (steep hill), a series of curves over 3 km (double bend), and a surface with reduced grip (slippery road). The chevron boards confirm the line of the curve and warn that the outside of the bend is where vehicles leave the road.
Taken together they mean: reduce speed before the descent, not during it; select a lower gear so engine braking carries part of the load and the footbrake is not held on continuously down a long hill, which causes fade; keep dipped headlights on; do not overtake; and expect the curves to tighten.
50 km/h is the legal maximum in good conditions, not a target. In heavy rain, on worn rear tyres, on a downhill bend with a diesel film, the appropriate speed is the one at which you could stop within the distance you can see - well below the limit. A signed limit is a ceiling; the hazard sets the actual speed.
2. What is your plan for the tro-tro in front and the pick-up behind?
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The tro-tro is the bigger problem. Repeated brake-light flicks on a descent usually mean the driver is braking late and often - possibly for passengers, potholes or speed ramps - and a vehicle that brakes unpredictably needs a large gap, not a small one. Drop back to at least four seconds in these conditions so that you gain a view around it and have room to react.
Overtaking is off the table here: restricted view on a bend, wet surface, diesel ahead, and a slow-moving vehicle that would keep you exposed on the wrong side for a long time. Do not follow a gap that someone else creates.
For the pick-up behind: do not brake sharply to create the gap, or it will run into you. Ease off the accelerator gently so the gap opens while your brake lights stay off. Keep well to your side, and where the road straightens let the pick-up go past rather than holding it up - but never wave it past into a bend or over a crest.
3. You reach the diesel film. What do you do, and what do you do if the car begins to slide?
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Slow down before it, not on it. Cross the film as upright and as straight as you can, with the steering held steady and no braking - a tyre already short of grip uses whatever it has for either turning or stopping, not both. If there is room inside your lane to go round the worst of it without altering your line sharply, do so.
If the car starts to slide, ease off the accelerator smoothly and steer gently where you want the front to go. Do not stamp on the brake, do not snatch the wheel back the other way, and do not accelerate out of it. Sudden corrections on a low-grip surface turn a slide into a spin, and on a descent with chevron boards on the outside there is very little room to recover.