This article discusses the controversial subject of undertaking, where a vehicle in one lane passes a vehicle in another lane nearer the road's centre. It can be argued that more road space would be used if undertaking were made legal in the UK, as it is already in many other countries. In fact, in the UK, undertaking is legal in queues of traffic moving slowly and in one-way streets or networks. One of the most difficult manoeuvres that a driver can make can occur when joining a motorway or other dual carriageway from an access road. Fine judgement of speed, distance, positioning, and anticipation skills, are required to estimate the speeds of the opening and closing gaps, while selecting the target gap. Sometimes this requires speeding up to merge with traffic in the first lane, thus undertaking vehicles in that lane. This manoeuvre requires flexibility and good observation of other drivers. To take another example, if a fast driver in lane one approaches a slow driver in lane two, he is required by UK law to pass in lane three, after which he can move back to lane one. As this process is inefficient, perhaps undertaking should be allowed in some motorway stretches, with signs displaying this permission. Often, drivers travel too close together. If sudden braking occurs ahead due to overacceleration, this can force other drivers into overbraking, which is very stressful.

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    CROYDON,   United Kingdom  CR0 4XZ
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  • Publication Date: 2000


  • English

Media Info

  • Pagination: p. 20-1
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00799633
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD
  • Created Date: Oct 6 2000 12:00AM