september.org> 52E9FFA6   
   From: rcp27g@gmail.com   
      
    wrote:   
   > The latest Trains magazine had an article about "modern streetcars".   
   > These are an improved version of the light rail vehicle (which in turn   
   > was an improved version of the classic streetcar).   
   >   
   > It described them as:   
   > --very low flow, with most or all seats on the entry level with no steps.   
   > --articulated with numerous sections, no couplers.  Articulated sections   
   > are added to increase car capacity, not more cars coupled together.   
   > --more street operation, very simple stations.   
   > --Portland is one example, other cities are planning them.   
   > --lithium ion batteries or "super capacitors" to allow limited off wire   
   > operation* (it still needs tracks).   
   >   
   >   
   > *I don't know what a 'super capacitor" is.  Some trackless trolleys have   
   > batteries to run off wire for short distances, such as for emergency   
   > detours.  would anyone know how that feature works in actual practice?   
   >   
   >   
   > Frankly, I didn't really see any substantive differences between them and   
   > traditional light rail.  Light rail systems vary quite a bit depending on   
   > location, and in some cases, have the same characteristics as a "modern   
   streetcar".   
      
   The term "light rail" is quite ill-defined. It came about when the words   
   streetcar and tram in the English speaking world were associated with the   
   systems mostly removed in the 1950s and 60s that had not progressed beyond   
   1930s levels of technological development. When second generation systems   
   drawing on developments in Europe from the 1960s and beyond we're being   
   proposed the term "light rail" was used to differentiate from the abandoned   
   first generation systems that had a bad image. In Europe light rail systems   
   have gone in two directions. One is to make the system more metro-like with   
   dedicated, often underground track, level boarding from high level   
   platforms and the like, as epitomised by the German "Stadtbahn" or Belgian   
   "pre metro" ideas, and the other is to use low floor trams and minimalist   
   tram stops to keep the systems more tram-like. It seems the term light rail   
   is becoming more strongly associated with the Stadtbahn type system. The   
   first generation systems are now long enough ago abandoned that the   
   negative connotations have generally been forgotten so the name can return   
   for the more low profile trams.   
      
   I do wonder the extent to which power independence is useful for a tram,   
   though. On a trolleybus, the utility is clear, but if you need tracks to   
   run a tram on, the restrictions of being tied to an overhead wire are not   
   significant. The only use case I can see for them is in locations where the   
   visual intrusion of overhead power is undesirable.   
   Robin   
      
   --- SoupGate/W32 v1.03   
    * Origin: LiveWire BBS -=*=- UseNet FTN Gateway (1:2320/1)