Paper presented at the 31st Annual Southern African Transport Conference 9-12 July 2012 "Getting Southern Africa to Work", CSIR International Convention Centre, Pretoria, South Africa.
Railways are inherently competitive when they exploit their strengths of heavy axle load,
high speed, and many coupled vehicles. However, urban guided transit, whether steel- or rubber tyred, naturally achieves neither heavy axle load nor high speed: Many coupled
vehicles are its only comparative advantage. Four lighter guided transit modes have
therefore made inroads into rail’s traditional domain. The authors hypothesized that
country and city attributes influenced which guided transit mode or modes fitted particular cities. They populated a database with ninety-eight variables from three hundred and thirty cities, and applied the statistical interventions multivariate factor analysis and structural equation modeling to it. Findings included seven country latent variables whose regression coefficients pointed to the positioning of Heavy Metro, Automated Guided Transit, Monorail, Light Metro, Bus Rapid Transit, and Light Rail: Heavy Metro and Light Rail now represent the poles of an urban guided transit continuum, in which rubber-tyred automated modes have penetrated rail’s traditional market space. In conclusion, green cities require more nuanced guided transit solutions that also address lower capacity requirements. In South Africa, alternative contemporary guided transit solutions to the challenges of long commutes to and from low density communities should be considered.
