The Overtake That Runs Out of Road
You are riding a 650cc motorcycle on a single-carriageway road with a 80 km/h limit. Ahead, a tractor pulling a trailer is doing about 25 km/h. You have followed it for two kilometres and the road has been clear. You check your mirrors, signal, and move out to overtake. As you draw level with the tractor's cab, you see a crest about 150 metres ahead, and beyond it the roof line of an oncoming car appears. Your speed is now 95 km/h, the tractor is still beside you, and the oncoming car is closing at roughly 80 km/h. You estimate you need another 60 metres to complete the pass and pull back in.
1. Work out whether you can complete the overtake before meeting the oncoming car, and state what you should do.
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Closing speed: you are doing 95 km/h and the oncoming car about 80 km/h, so the gap between you closes at 175 km/h, which is about 48.6 m/s.
Distance to the meeting point: the car's roof appeared at the crest 150 m ahead. If the car is just over the crest, the gap is roughly 150 m, but treat it as less because you cannot see the road surface beyond the crest.
Time available: 150 ÷ 48.6 ≈ 3.1 seconds.
Time needed: at 95 km/h you cover about 26.4 m/s. To gain the 60 m you still need relative to the tractor (you are closing on it at 95 − 25 = 70 km/h ≈ 19.4 m/s), 60 ÷ 19.4 ≈ 3.1 seconds - and that is before you have actually cleared the tractor's length.
The margins are effectively zero and the estimate is optimistic. Abort the overtake: brake firmly, drop back behind the tractor, and pull in behind it. Do not try to 'beat' the car. A crest hides the true distance and closing speed; never commit to an overtake you cannot finish with a clear margin before a blind point.
2. Identify the specific errors in the rider's decision-making and the rule that should have prevented them.
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- Overtaking toward a crest: the road ahead was not visible for a sufficient distance. You must be able to see far enough ahead to complete the manoeuvre and return safely; a crest is a blind hazard, not a clear road.
- No forward observation before committing: the rider checked mirrors but did not confirm the far side of the overtake was clear before moving out.
- Speed build-up: accelerating to 95 km/h in an 80 km/h zone to force the pass increases both the closing speed and the stopping distance.
- No abort plan: the rider had not decided in advance at what point to give up. A good rule is to set a 'commit point' - if the pass is not clearly achievable before that point, drop back.
Correct approach: only overtake where you can see the whole manoeuvre is clear, keep within the limit, and be willing to abandon immediately.