02-19-2018, 08:37 PM
(02-19-2018, 05:45 PM)Canard Wrote: Yes, it does - it allows a train to come in on Platform 1, and sit for a little bit longer (gives that operator a moment to take a washroom break, etc.). Next train comes in and uses Platform 2, and does the same thing. Now the first train that came in on Platform 1 can leave. It doubles the time that a particular LRV can wait at the end. If it's lunch time for that operator, it might sit there for a couple of cycles. etc...
(basically, exactly what you said - it affords flexibility.)
One end of G:link was done as a single track but it's actually double tracks and they extended a "temporary-ish" platform over the second tracks. It has a single half crossover IIRC. As many of the same system partners built our line I'm assuming they decided it seemed like a good idea on paper to do that but in reality the extra flexibility to have two terminus tracks would be nice to have, and added it into our design.
I would say that if two LRVs are regularly present at the end of the line, just get rid of one of them. Even if the operators need a substantial layover, the vehicles don’t. There is no reason to keep operators attached to their vehicles. This is especially so at the headways we are planning — with never less than 7 minutes between trips, there should not be any terminal congestion at all. Having said that, having a place to stash a vehicle out of the way isn’t a bad idea. But then again, that’s also true in places not at the ends of the line, and we don’t have any storage tracks at all (other than at the OMSF).
I’ll be interested to see how the tracks actually get used at the ends of the line, as potentially evidenced by rust and wear patterns, once the system has been open for a time.
An in-between terminal solution is used at Santee Town Center on the San Diego Trolley. The two tracks reduce down to one after the 2nd-last station, and continue to the last station, where they split into two tracks serving two platforms. This gives almost all the benefits of the double crossover and extra platform track. The only limitation is that you can’t have a train arriving and leaving simultaneously. But at our headways that is never necessary anyway so it’s not a real limitation. If I recall correctly the second platform’s rails are fairly rusty but it’s been a while since I was there so I might be wrong or things might have changed.