Quote Originally Posted by Steve Smith View Post
There are some stations on the London Underground now which are totally sealed off between the platform and the track with sliding doors which only open when a train is present. I expect to see a lot more of these in the future.


Obviously the train driver now has to stop in exactly the right place!

In Paris Line 1 has automatic doors. I also suppose these will be the norm in the future, as they can be "retrofitted" to old platform. I wonder what happens when the crowd is "pushing" to enter thus slowing the closing of the doors.

With the double doors the persons trying to catch the train no matter what will slow the closing of the doors much more I suppose. Some people might remain with bags, umbrellas etc. "in between".

Now that I think about it, one of the things that slow underground train operations is that people must first get off, then people can get on. People trying to get on, in crowded stations and situations, are an obstacle to people getting off.

With modern trains which have carriages communicating with each other (a long "snake" where you can walk freely) tube trains could be optimized so that let's say the first carriages are for getting on only, and last carriages are for getting off only. That would make the pavement traffic "one way". All the internal paths of the tube stations could be optimized so as to avoid double senses of circulation.