Related topic: I presume an ETC failure (CBTC signal problems) instantly failovers to the traditional track signals, and upon being inside a restricted block (during CBTC signal loss situation) results in a train immediately braking automatically to prevent enroaching into last-known train positions.
I assume the legacy block signals are kept as a failover for CBTC fail. I also assume it depends on the specific operating rules ultimately chosen/permitted by Transport Canada. Specifics such as allowing CBTC to let trains enroach into certain kinds of restricted blocks (a traditional block already in use or adjacent to one by another CBTC equipped train, but has room for a second CBTC-equipped train) a little bit more permissively for shorter headways than the traditional block signals would permit in current operating rules.
For readers not aware, CBTC can allow trains to follow trains closely at braking distance in a continuous moving block system. Probably not done right away, but CBTC is a very key piece of a "moving block" system, if traditional block signals eventually only became a failover rather than the primary system on the Meteolinx segment of the rail network... You could eventually in theory permit CBTC to become the primary signal system in the CBTC corridors, but initially they might do CBTC only informationally, and then to raise yellow-signal speed limits (for yellows causes by CBTC equpped trains in block ahead).
Allowing CBTC-equipped trains to stay at speed longer, and shorten headways a little bit by bit... till they trust CBTC to become the primary and let two CBTC equipped trains into the same long traditional block at full track speed... (Eek! Bet you train drivers really need some years to fully trust CBTC first before this happens).
Negotiations with Transport Canada presumably includes niggly little details like this...an a staged transition process taking years or decades...
Basically varying extents of less/more restrictive versions of a possible moving block system overlay on fixed blocks, with a clear and safe failover sequence.
I have not seen CBTC equipment inside a cab, but presumably it needs to be GOOD STUFF enough to be trusted by the train driver going through peasoup fog behind a rail curve past a legacy red trackside signal... Easily seeing the trains ahead and behind in a user/operator-friendly manner.
A long term gradual operating rules migration path of some kind between prioritizing one control system over the other. And obviously, all rules for programming an automatic stopping sequence on a danger conditions, and years of simulating/realife testing in the CBTC transition. CBTC would become informational at first, then suggestive, then change yellow operating rules, shrink any introductory safety margin, then finally the verboten full speed into fixed red block (if red signal is only because of a CBTC train inside it but far ahead of braking distance)... At least rougly along these lines, in theory. Obviously, not the full progression necessarily for "RER Phase I"
We are possibly going to end up becoming one of the largest North American commuter rail systems to do a long term transition to a moving block system, given the short headways being thrown about (4mins, 6mins, 10mins)...
Stevetoronto, any guidance/docs by FRA or ERA / etc on a slow transition from fixed blocks to moving blocks via CBTC overlay on traditional signalling?
Vegata/smallspy?