Overtaking a slow truck before a blind crest
You are on a single-carriageway road with one lane each way and a broken white centre line. Ahead is a loaded haulage truck doing about 45 km/h. You are doing 90 km/h and want to pass. The road rises to a crest about 150 m ahead, and beyond the crest you cannot see the oncoming lane. There is a solid white line beginning about 120 m ahead where the road narrows for a bridge. An oncoming car is visible in the distance but you cannot judge its speed. Your passenger says 'go now, it's clear'.
1. Should you begin the overtake now? Justify your decision using the road features.
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No. The decision is governed by what you can see, not by the passenger's opinion.
- The crest 150 m ahead hides oncoming traffic. You cannot confirm the oncoming lane is clear for the whole manoeuvre, so the overtake is blind.
- The solid white line starting in 120 m marks a section where overtaking is prohibited; you would be committed to completing the pass into a no-overtaking zone.
- The oncoming car whose speed you cannot judge is an unresolved hazard - at closing speeds a misjudgement is fatal.
- A loaded truck at 45 km/h means a long time alongside it, not a quick pass.
Correct action: hold back, keep a safe following gap, and wait for a clear straight with uninterrupted visibility and a broken line. The passenger has no responsibility for the outcome; you do.
2. What following distance and position should you hold while waiting, and why?
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Hold back so you can see past the truck and be seen:
- Increase the gap beyond the normal minimum - at 90 km/h you cover 25 m per second, so a 2-second gap is about 50 m; give more so you have sight-line around the truck's bulk and room to accelerate into a gap.
- Position slightly toward the left of your lane (not straddling the centre line) so you can see oncoming traffic past the truck without exposing yourself.
- Never tailgate: a loaded truck braking for the bridge or a hazard gives you no reaction room, and you cannot see the road ahead through it.
- Watch the truck's mirrors and indicators; a truck may itself be preparing to move or turn.
3. Halfway through a later overtake you realise the gap is closing faster than expected. What is the safe recovery?
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Abort early rather than commit:
- Brake and drop back behind the truck, using your indicators to signal the abandonment, rather than trying to out-accelerate an oncoming vehicle.
- Do not swerve back into the lane if the truck is alongside that space; check your mirror and blind spot before returning.
- If you are already alongside and cannot drop back safely, accelerate decisively only if the lane ahead is genuinely clear - but the default is to yield and return.
- After the incident, re-establish the safe following gap and do not attempt again until visibility is uninterrupted.
The lesson: an overtake you cannot complete and abandon safely should never have been started.