Not to difficult if all the cars run on the line, old and new, have the same length and doors in the same place on the car. It's a matter of physical dimensions on the capital equipment you already own.
On Sun, Feb 24, 2013 at 10:26 AM, Bob W <p...@web-options.com> wrote: >> From: PDML [mailto:pdml-boun...@pdml.net] On Behalf Of John Sessoms > [...] >> > >> > I saw on TV recently a shot of a subway station somewhere where they >> > had fully enclosed the platform with doors that match up with where >> > the train stops (imagine like a horizontal elevator). May have been >> > the series about great cities hosted by Gryff Rhys Jones. Something >> > tells me it was Tokyo but I'm not sure. >> > >> > It made me wonder why other cities haven't done this. >> > >> > Cheers, >> > Dave >> >> The subways in Hong Kong and Beijing both had those kind of barriers. I >> can't remember if Nanjing had them or not, but I think they did. >> >> It would probably be *very* expensive to retro-fit them to existing >> systems. You not only have to install the door mechanism, but find some >> way to make the trains stop in exactly the right spot every time so >> they line up with the doors. > > I don't think it would be particularly difficult. The trains have to stop in > more or less the same place anyway, and regulars get to know where the doors > are. > > When they built the Jubilee Line extension here a few years ago they put > platform doors on at the new stations, but the old stations still don't have > them, so there is a mixture on the one line. For a few weeks after the new > ones opened there was the occasional delay while they lined the trains up, > but that was just teething trouble, presumably until they got the tolerances > right and all the drivers fully trained. > > It's far more convenient than having unpredictable delays and line closures > because some selfish sod has thrown themself in front of a train. > > B > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.