Q What are the legal overall lengths of vehicles, in particular a rigid, an artic and drawbar outfit?
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AOverall lengths of vehicles are governed by the Motor Vehicles (Construction and Use) Regulations 1973,
Section 9(1) states that the overall length of an articulated vehicle shall not exceed 15 metres (48ft 9in. approximately) except for articulated vehicles constructed to carry indivisible loads of exceptional length. Subsection (3) says that in all other cases the overall length of a vehicle shall not exceed 11 metres (35ft 11 in. approx), and Section 128(1) that where a vehicle is drawing only one trailer the overall length of the combination of vehicles shall not exceed 18 metres (58ft 6in. approx).
The answer to your query, therefore, is that a rigid vehicle's overall legal length is 11 metres, an artic's 15 metres, and a drawbar outfit's 18 metres.