That is one of the constraints that I considered. I would guess that an 8 car train at 602' in length may have trouble fitting in the maintenance facilities, but I am not as sure for the 530' (actually 527'2") 7 car train. If someone would post information (drawings, official quotes, etc.) that pocket tracks and maintenance facilities are not able to accommodate 530', then I accept that this 7 car train idea will not work.
The system was designed from the outset for ~500 foot long trains, and all of the facilities - platforms, signal system, tail tracks, maintenance facilities, etc. - were designed for that. (In fact, the physical layout of the maintenance workshops were designed for 150 foot long pairs of cars, and the ones at Wilson and Davisville had to be rebuilt to handle the 450 foot long TR sets.) They aren't designed for a 7th full-length car, which is why the TTC has always been talking about a 50 foot long car, not a 75 foot long one.
As for fixed blocks, they only seem to apply in case of problems with moving block. The length of the train from front to last axle is 510'. Could the actual blocks have a small amount of safety built in that they are not exactly 500' 0" apart?
With certain exceptions in certain areas, blocks are 2x ~500 feet long with very minor variances for equipment layout and locations. A train that is 510 feet long may cause problems because not every block is the exact same length, and the distance between two regular signals may in fact be shorter than the fixed length of your proposed train.
Since the signalling is currently going on, hopefully they are smart enough to accommodate 7 and 8 car trains.
Why and how would they be "smart enough" to handle something that is only a hypothetical situation? They already have a plan in place for a 7th car that will fit within their current and planned future length limitations. While I suspect that they are looking at their future options, I highly doubt that they have come close to setting anything in stone.
Nobody ever walked between subway cars. Not sure, but I recall it was either illegal or highly frowned upon. Torontonians have been trained to not walk between cars.
You must lead a rather sheltered life. Yes, it is forbidden, but it happens not completely infrequently, sometimes by people who are not even employees. The horror!
It still surprises me when I see it on a GO train, maybe every 10th trip I see someone do it, so it is not non-existant, but I do not think the average person would even consider it.
If that surprises you, I can't help but wonder what else does.
Again, as I and others have indicated, people walk from car-to-car on GO trains all the time. It is allowed, and in fact, the most recent cars make it even easier to do.
Based on the platform drawings I was able to find online, 100% of platforms can be extended. I would like if someone could prove me wrong. Of special interest would be the key stations along the Yonge-University Line.
That's some pretty shoddy research.
There is very little space at the platform level that is not used on any given platform. If a platform is extended into an equipment room or ventilation room, that equipment room or ventilation room will have to be built elsewhere. On top of that, you haven't taken into account any curvature or grades at any stations - St. Clair, for instance, will be a huge issue to lengthen any amount as there are curves and grades at either end of the platform.
It would only be one set of doors at the front and/or back of the train. Also, this area would be clearly marked on TTC maps, the platform, and in the car itself as to the fact that the doors only open at select stations (or not at all). I have been on trains with inoperable doors and the train continued all the way to the terminal. Even without advanced warning, people figure it out. If there were any safety requirement about all doors opening, these trains would have been taken from service immediately.
Riiiiiight. People don't read or pay attention to much of what they are told today, and you want to give them even more information to ignore.
I am not sure if this means that the driver currently has full control to operate each set of doors independently, or not. It does not seem to be that hard to implement. I do not think it wise for the train doors to open in the tunnel, but some type of permanently closed screen doors in the tunnel that actually prevent people from exiting the open door. Screen Doors along the platform would be another issue separate from this.
Subway operators on the TRs have the capability of individually controlling which doors open and which don't. It is not done in such a way that they can do it on a station-to-station basis.
My apologies.
I was incorrectly under the impression that the lengths of the individual fixed blocks were a function of the the worst possible stopping distance (accounting for weather, grade, friction, speed, weight, etc...).
It's a bit more complex than that, but for simplicity's sake, they are.
The TTC uses an overlapping fix block system. When a train is occupying a block, the number of blocks behind the train that other trains will not be permitted to enter will be equivalent to the worst possible stopping distance. So for example, let's say part of the line has an arrangement of blocks:
B1 -> B2 -> B3 -> B4 -> B5 -> B6 -> B7 -> B8.
If a train is occupying B8, and under worst possible circumstances it takes 4 blocks for a train to stop, then typically no vehcile will be permitted to enter B4, B5, B6, B7 or B8.
That's the basic jist of it although the truth is a bit more complex than that, because the signal system in the subway uses overlapping blocks to allow for protection and to still allow trains behind to operate closely. To use your diagram, the block guarded by a signal at B1 stretches to B3, the signal at B2 to B4, etc. What you have described is basically how the mainline railways operate, although there is additional logic to allow for the varying lengths of signal blocks.
The other half of the purpose of the signal system is to warn trailing trains about the location of trains ahead of them, which would then in theory cause the driver of the trailing train to slow down. There is now an overlay on the signal system - the Speed Control System (SCS) - which enforces lower speeds in locations with restrictions and at restrictive signals.
So in other words, the number of blocks that a vehcile will not be permitted to enter is a function of the stopping distance under worst possible circumstances.
Correct.
The length of a signal block is approximately the length of the passenger platforms.
Is this correct?
Incorrect. A signal block is approximately 2 passenger platforms. The distance between two signals, however, is about the length of a passenger platform.
Keep in mind that the connection between GO trains is enclosed, though it is separated by a couple of doors. Semi-articulated perhaps?
No. The term articulation indicates that the vehicles share a structural connection, which GO cars (and subway cars, for that matter) do not. It is more correctly termed an enclosed gangway, although the actual covers are called diaphragms.
Dan
Toronto, Ont.
