A comment in my review of David Miller’s platform triggered a technical discussion about this issue. To segregate this from the thread on Miller himself, I have moved the relevant information here. If you plan to add to this issue, please do so here.
The issue was previously reviewed in this post.
I made the comment:
Mayor Miller claims that we will improve capacity on the Yonge line by 40% through new trains and signalling. Running the trains more frequently will require changes at Finch Station (probably a northerly extension) to allow for faster turnarounds, and will definitely require some changes on the Spadina line (currently planned as part of the York U extension). Don’t plan to see those empty, uncrowded trains until a decade from now, at least.
This provoked various responses:
Mark Dowling Says:
There are YUS signalling changes planned for 2016 (mentioned in connection with 24hr subway) – why is it that far out and would there be realistic advantage to daytime service to bring it forward?
Steve: Unless there are major changes in the operation at both Downsview and Finch terminals, it is impossible to get a shorter headway than about 115 seconds. This is a function of the physical layout (a very long crossover). The TTC intends to deal with the Spadina leg via the York U extension and a high speed pocket track beyond Downsview that will allow trains to operate in and out at speed. At Finch, there are no plans in the pipeline, although occasionally we hear mutterings about an extension to the north to permit a revised turnaround scheme beyond the station. If they’re going to do that, they may as well go to Steeles and design a new terminal there and relieve the surface congestion of bus routes.
James Bow Says:
It might be boring to some readers, but I’d like an explanation of why the current crossover arrangement at Finch limits turnaround times to 115 seconds, and what can be done to fix this?
Would it be better, instead of using the crossover to the south of the station, to pull the trains into the “northbound” platform, unload, then rush them into an improved version of the tail tracks at the north end of the station, change ends there (with a special platform where the replacement train crews are waiting, and then run back onto the southbound platform to load passengers?
Steve: James — I have already written this up in this post. In order to do what you propose, you need to be able to get into and out of tail tracks quickly. To do this ideally requires that the new crew board while the train is sitting on the northbound track so that they are ready immediately to set up and operate the train southbound from the tail track. The old crew would get off at the southbound platform.
One problem we have in Toronto compared to a city like Boston that uses farside turnarounds is that the trains in Boston are much shorter, and the farside crossovers are very short. Also, there is quite a lot of terminal time for operator breaks compared with Toronto.
For additional responses, visit the original item.