Definition
A semi-trailer is a trailer built without a front axle, designed to be coupled to a tractor unit so that a substantial part of its weight rests on the tractor. Tractor + semi-trailer is the most common heavy-goods configuration on European roads.
Key facts
- No front axle: rests on the tractor via the fifth wheel.
- Maximum combined length: 16.50 m.
- Driving a tractor + semi-trailer requires a C+E licence (or D+E for passenger transport).
- Different from a full trailer, which has a front axle and only connects via the hitch.
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