Unmarked Intersection at Dusk with a Stopped Truck
You drive a Category C truck on a two-lane rural road at 18:40 in October, dusk, dry asphalt, headlights on low beam. Ahead is an unmarked T-junction where a secondary gravel road joins from the right. A loaded truck stands at the mouth of the gravel road, its left turn indicator flashing, nose slightly past the stop line but not yet on the asphalt. Your lane is clear for about 120 m. Your speed is 70 km/h, the posted limit for this road is 90 km/h, and the truck's gross combination mass is 18 t. A car follows you at roughly 25 m. You cannot see whether the gravel road continues behind the standing truck, and there is no sign indicating priority.
1. Who must yield at this junction, and how does that change your approach speed and lane position?
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An unmarked junction between a paved road and a gravel road is normally resolved by the surface: the vehicle leaving the gravel road must yield to traffic on the paved road. So the standing truck should wait for you. But the indicator and the nose past the line show the driver may have misjudged the rule or the gap, so you cannot rely on the right of way being respected.
Practical response: lift off early rather than brake late, aim to arrive at the mouth at no more than about 40-50 km/h so that a stop is possible within the visible clear distance. Move slightly left of lane centre only if the oncoming lane is visibly clear, to widen the lateral gap to the truck's nose. Do not flash headlights or wave the truck out: a signal that contradicts the rules can transfer fault and confuse the following car.
2. The following car is 25 m behind at 70 km/h. What is the risk if you brake hard at the junction, and what do you do about it?
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At 70 km/h you cover about 19.4 m per second. A following car 25 m back has barely 1.3 s of gap, well under the 2-second minimum and far under the 3-4 s a heavy truck needs because its braking distance is longer and its brake lights sit high and far from the follower's eye line.
If you brake sharply, the follower is likely to close and rear-end you. Mitigations: brake progressively and early, using the first 2-3 seconds of deceleration to light the brake lights and shed speed gradually; tap the brakes once before the main application to warn; keep the wheel straight while braking so the truck does not yaw; and if the follower closes to under 15 m, consider letting the truck at the junction go first rather than stopping abruptly in front of a tailgater. A rear-end collision at 70 km/h into an 18 t combination is survivable for you but severe for the car, and you will still be judged on whether your braking was foreseeable and smooth.
3. The truck at the junction begins to pull out when you are 60 m away. What is your plan?
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At 60 m and 70 km/h you have roughly 3 s to the conflict point. A loaded 18 t combination accelerating from rest onto asphalt needs several seconds just to clear its own length, so it will be in your path.
Plan in order: (1) firm braking within the tyres' grip, straight line, no swerving into the oncoming lane unless it is confirmed empty; (2) sound the horn once to make the truck driver aware, since he may be watching his mirrors and not the road; (3) if stopping distance is short, steer right toward the gravel shoulder only after checking the mirror for the follower, because a shoulder excursion is preferable to a T-bone into a truck cab; (4) after stopping, do not proceed until the truck's cab and trailer are fully clear and the driver has seen you. The key judgement is committing early to braking rather than hoping the truck stops.