Overtaking a slow tractor with an oncoming car
You drive a category C lorry at 80 km/h on a single-carriageway road outside a settlement where the general limit is 90 km/h for cars but 80 km/h for lorries over 3.5 t. Ahead, a tractor with a trailer is moving at 25 km/h. The road has a broken white centre line, a solid white line begins 120 m ahead on a crest, and visibility over the crest is limited. An oncoming car is visible about 250 m away, approaching at about 90 km/h. Your lorry is 8.5 m long and you are loaded to 16 t; acceleration from 25 km/h to 80 km/h takes roughly 25 seconds when fully laden. There is a side road on the right 60 m before the tractor. The tractor has no rear lights working and its trailer has an obscured number plate.
1. Assess whether an overtake is possible here, showing the distance and time reasoning.
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Assessment:
- Closing speed with the oncoming car: your 80 km/h plus its 90 km/h = 170 km/h ≈ 47 m/s. In the time you are on the wrong side, the gap of 250 m closes fast.
- Your acceleration is slow: 25 s from 25 to 80 km/h fully laden. In 25 s the oncoming car covers about 625 m at 90 km/h, far more than the 250 m gap. Even allowing for the tractor's length and your own 8.5 m, an overtake started now would meet the oncoming car head-on.
- The solid line begins in 120 m and the crest limits visibility, so the available overtaking zone is short and the view is not clear.
- The side road 60 m before the tractor is another hazard: the tractor may turn right, or a vehicle may emerge.
Conclusion: an overtake is not possible. The correct action is to hold back at a safe following distance (at least 2 seconds, more for a slow vehicle with no lights), and wait for a clear straight with full visibility and no solid line.
2. What speed limit applies to you, and what should you do about the tractor's defective lights and plate?
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Speed limit:
- As a lorry over 3.5 t, your limit on this road is 80 km/h, not the 90 km/h that applies to cars. You are already at your limit, so there is no speed advantage to gain by overtaking; you would be committing an offence if you exceeded 80 km/h during or after the manoeuvre.
Defective tractor:
- The tractor's lack of working rear lights and the obscured trailer plate make it hard to see and identify. You should increase your following distance so you can see and react, and use your own lights appropriately.
- You cannot enforce the law on the tractor driver. Do not tailgate or overtake aggressively to 'make a point'. If it is safe and you have hands-free means, report the vehicle to the police with its description and location; otherwise note it and continue.
- Do not attempt to read the plate by driving close behind; that is exactly the situation where a sudden stop would cause a rear-end collision.
3. The tractor signals right toward the side road. How does this change your plan?
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Change of plan:
- The right signal means the tractor may slow sharply and turn into the side road 60 m ahead. Do not begin any overtake, and do not pass on the right as it turns; a turning heavy vehicle may swing wide or cut the corner.
- Increase the gap, reduce speed to match, and be ready to stop if the tractor brakes late or a vehicle emerges from the side road.
- Watch for the tractor's trailer cutting across your path and for any following vehicle that might try to overtake you both.
- After the tractor turns, you may continue at up to 80 km/h, but only once the road ahead is clear and you are past the side road. The defective lights remain a reason to stay alert if the tractor rejoins the road.