Night Rain on an Unlit Curve
It is 11:30 pm and you are driving an older sedan on an unlit two-lane highway. Heavy rain is falling and your wipers are on their fastest setting. The speed limit is 90 km/h and you are travelling at 80 km/h. Your headlights are on low beam. Ahead, the road curves sharply to the left, and the painted edge line is hard to see through the spray. Your tyres are about four years old with 3 mm of tread remaining. A faint reflection appears on the wet surface near the outside of the curve, possibly a puddle or a stranded vehicle. You feel the steering go slightly light for a moment. You must decide how to adjust speed, lights, and line before the curve.
1. Interpret the light steering and the faint reflection, and decide what to do before entering the curve.
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Light steering on a wet road is an early sign of reduced grip, often the start of aquaplaning. The correct response is to ease off the accelerator smoothly and avoid sudden braking or steering inputs, because either can break what grip remains. Do not stamp on the brakes; let the tyres regain contact with the road and keep the wheel steady in the direction you want to go.
The faint reflection could be standing water or a vehicle with failed lights. Either way, it is a reason to slow down before the curve, not in it. Reduce speed while the car is still travelling straight, so braking forces are spread evenly. Switch to low beam if you are not already there, since high beam reflects off rain and spray and reduces your own vision. If the reflection turns out to be a stranded vehicle, you need stopping distance, and at 80 km/h on wet pavement that distance is much longer than on dry tarmac.
2. Explain how the tyre condition and the curve geometry should shape your speed and lane position through the bend.
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Tread at 3 mm is well below the depth needed to clear water effectively, so the tyres are more prone to aquaplaning and take longer to stop. That means your safe speed is lower than the posted limit and lower than what a car with fresh tyres could manage. Treat 80 km/h as too fast for this curve in this rain.
Slow to a speed where you can stop within the distance you can see to be clear, which on an unlit wet road is roughly the reach of your low beams. Enter the curve slower than you think you need, then maintain a steady speed or gentle acceleration through it; braking hard mid-corner shifts weight forward and can provoke a slide.
For lane position, stay centred or slightly toward the inside of your lane, away from the outside edge where water pools and where the reflection appeared. Do not cross the centre line to widen the arc, because oncoming traffic may be invisible in the spray. Keep both hands on the wheel and make small, smooth corrections.