To reduce the space needed for transportation, both the physically and the socially perceived size of urban transportation facilities must be reduced. This means reducing the time spacings between moving vehicles, as well as their space consumption when stopped. Reducing time spacings requires automating the driver function--with vehicles under automated operation short headways (time spacings between vehicles) on automated guideways. To equal an eight-lane expressway's capacity, a two-lane guideway would have to carry four times as many vehicles per hour. True personal rapid transit means personalized vehicle service and fraction-second headways. Without fraction-second headways, passengers must be assembled to boost line-haul capacity, service is degraded, and per-mile system costs are increased. Thus, significant improvement in urban transit service in general also requires very-short-headway systems. Fraction-second headways are the only way to lighten transit vehicles and reduce structure size and costs--both direct costs and the social costs of large guideway structures and, similarly, urban highways.

  • Availability:
  • Corporate Authors:

    Massachusetts Institute of Technology

    Alumni Association
    Cambridge, MA  United States  02139
  • Authors:
    • Brand, D
  • Publication Date: 1976-1

Media Info

  • Pagination: p. 38-45
  • Serial:
    • Technology Review
    • Volume: 76
    • Issue Number: 3
    • Publisher: Massachusetts Institute of Technology
    • ISSN: 1099-274X

Subject/Index Terms

Filing Info

  • Accession Number: 00141106
  • Record Type: Publication
  • Source Agency: Engineering Index
  • Files: TRIS
  • Created Date: Oct 26 1981 12:00AM