Night Rain on the Tutong Coastal Road
It is 21:30 on a two-lane coastal road in Brunei. Heavy rain has been falling for an hour; standing water crosses the road in patches and the wipers are on their fastest setting. You are driving at 80 km/h, the posted limit, with dipped headlights on. Ahead, a lorry without working tail lights is crawling at about 30 km/h, and its spray makes it nearly invisible until you are roughly 60 metres away. Your tyres are legal but worn to about 2 mm of tread. A car behind you is following at a similar speed and distance. You feel a slight pull to the left as you cross a patch of standing water.
1. What is wrong with your speed and following distance, and what should you change?
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At 80 km/h in heavy rain you are overdriving your visibility and your tyres. The lorry only becomes visible at about 60 metres; at 80 km/h you travel roughly 22 metres per second, so 60 metres is under three seconds of travel - and that is before allowing for wet-road braking.
Changes:
- Reduce speed to something like 50–60 km/h. Wet roads and 2 mm tread mean a much longer stopping distance than the dry-road figure you may have memorised.
- Increase the gap to the lorry to at least four seconds, and more in spray. Pick a fixed object and count: if you reach it sooner than four seconds after the lorry, you are too close.
- Use dipped headlights - already correct - and consider rear fog lights only if visibility is genuinely poor, switching them off when it improves.
- Watch the car behind: a smooth, early reduction in speed gives it time to react; a sudden slow-down invites a rear-end collision.
The posted limit is a maximum for good conditions, not a target in a downpour.
2. You feel a slight pull to the left crossing standing water. What is happening and how should you respond?
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That pull is the early sign of aquaplaning: water is lifting the tyre off the road and reducing grip, and the worn tread makes it worse because there is less channel to clear water.
Response:
- Ease off the accelerator smoothly. Do not brake hard - braking a tyre that is already floating can trigger a skid.
- Hold the steering steady and avoid sudden corrections; the pull may correct itself as you leave the water.
- Do not accelerate through it to 'push' the water away.
- Once grip returns, reduce speed further and, if possible, move to a part of the lane with less standing water, while watching for oncoming traffic.
- Plan to check tyre tread and pressure soon; 2 mm is close to the legal minimum and is inadequate for sustained wet driving.
If the car begins to slide, keep steering where you want to go and release the accelerator; grip usually returns as speed drops.
3. The lorry has no working tail lights. What is the safest way to deal with it?
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An unlit slow-moving lorry in heavy rain and spray is a serious hazard, but the safe response is patience, not a risky overtake.
- Stay back at a four-second-plus gap so you have time to react if the lorry brakes or swerves.
- Do not overtake unless you can see a clear, long stretch ahead and the surface is not flooded. On a two-lane coastal road at night in rain, spray from an oncoming vehicle can hide an approaching car until it is too late.
- If you do decide to overtake, signal early, use a lower gear for control, and abort immediately if visibility closes.
- Report the lorry when it is safe to stop, or have a passenger note its details; an unlit vehicle is a danger to everyone behind it.
- Keep your own lights and reflectors clean so following drivers can see you.
The exam point is that a hazard you cannot remove should be managed by distance and speed, not by a bold manoeuvre.