In a truly breathtaking display mixing unrelated subjects in one press conference, Howard Moscoe has embraced Automatic Train Operation (ATO) as the salvation of much that is wrong with the TTC. A chicken in every pot (provided that you have a Metropass) will follow soon after.
You can read about Moscoe’s scheme on the Star website: TTC Eyes Driverless Subway.
In brief, our fearless leader claims:
- ATO will increase subway capacity by 40% at a fraction of the cost of building a new line.
- ATO will permit bidirectional operation on the same track which will permit maintenance to occur on one rail while the other stays in service for overnight operation
- ATO will allow one-person train crews freeing up staff to be used as “Station Managers”
As someone involved personally and professionally with Information Technology for much of my life (my earliest computer program of any significance dates to 1963), I’ve seen a lot of huckters for technology, for “solutions” looking for a problem. Typically, if something isn’t marketable on its own, people will lard on all sorts of additional claims and benefits. By the time the product is actually delivered, you usually find that these claims were misleading, or that there are many add-ons required to actually achieve those ends.
I smell exactly the same pattern at work here. After we turn off the hype, there are three basic requirements Howard Moscoe is trying to address:
- Increased subway capacity
- All night service
- Much improved station management (cleanliness, working escalators, etc)
The problem arises when these are bundled together as a package. For those of you who don’t want to plough through the technical details below, I will state my bottom line right up front:
We should not have to spend $750-million and wait at least ten years just so that tattered, out-of-date service change notices will be taken down, spilled food and drink will be cleaned up, and escalators can be restarted in less than a day. If the TTC wants to improve the look of and service level at its stations, this needs to be done now, and it has absolutely nothing to do with automated train operation.
Casual readers can stop here, but for the detailed evisceration of this proposal …
Running Trains Closer Together
I have written on this elsewhere, but since we are discussing Automated Train Operation, I should explain what it allows compared with the present system.
Train spacing is now controlled by fixed-length “blocks” between each signal. Generally speaking, there are always two red signals behind a train, and this effectively limits the degree to which trains can “close up” on each other. TTC operating practice for some years has been that a single red signal means “stop and stay” where previously in meant “stop and proceed with care” (this was before the Russell Hill accident). A double red is always a “stop and stay”.
The old rules allowed trains at congested points like Bloor Station to creep up on each other, and in fact I regularly saw the tail end of one train disappearing out of the north end of the station while the next train pulled in at the south end. This allowed trains to take a long time loading passengers while maintaining a close scheduled headway.
This type of operation will be vital for close headways. A computer system can monitor train locations at a much finer accuracy than the old signal blocks. The “moving block” system takes into account both the spacing between trains and their speed, but does not depend on fixed signal locations. This is the system used on the SRT. As you can see, it has been around for a long time.
However, problems arise wherever train movements might conflict such as terminals or turnback locations. There are physical contraints due to the need for slow operation through switches and the geometry of the track layouts. In practice, these are the controlling factors on the existing lines.
Adding 40 Percent To Subway Capacity
There are three ways to add capacity to any transit route:
- Run larger vehicles
- Run more vehicles -or-
- Run existing vehicles faster
The new subway cars (“Silver Snails” is my nickname pending something official) will increase capacity by about 11 percent because additional space is available in the gangways through the trains. This leaves about 26 percent to be found through closer headways. (Confused? The compound effect of an 11 percent increase and a 26 percent increase is almost 40 percent.)
Current peak service on the Yonge and Bloor lines is roughly one train every 140 seconds, or about 25.7 trains/hour. We need to increase this to 32.4 trains/hour to achieve a 26 percent increase.
However, existing terminals at Finch, Downsview, Kipling and Kennedy cannot sustain this level of service (one train every 111 seconds). As I have discussed previously here, the current 140 second headway is very close to the practical minimum (about 135 seconds). This is a function of track layout and train length, and, to a much lower extent, the reaction time of operators when signals change. ATO won’t get us anywhere near 111 seconds.
If intermediate short-turn locations are provided, then the headway at any terminal is widened. However, this assumes the existence of a turnback that can be operated on a razor-sharp basis to pull every other train out of the outbound stream and re-insert it to the inbound one.
Vancouver’s Skytrain did some very clever stuff during Expo, but had the advantage that trains were very short (they occupied the interchanges for less time than a Toronto subway train would need), and the operation was completely automated eliminating the need for an operator to change ends on the train. It was impressive, but doing that sort of thing on our subway would be challenging under even ideal conditions.
Next, the current order for subway cars will not even completely replace the fleet now in use on the Yonge line, let alone the Bloor line. If we are to achieve the capacity increase across both lines, we will need many more new cars.
One optional way of reducing fleet requirements is to change the speed of operation. For a few years in the late 1960s, the Bloor-Danforth line ran in “high rate” where the acceleration and top speed of trains was set higher than today. This did not work out for the following reasons:
- The then-current H-1 subway car fleet had a technical problem with the motors which failed at operating speeds around 45 mph.
- Higher speed operation requires that the trackbed be in better condition to preserve stability, and this costs extra money.
- Most of the system had stations close together, and the benefits of high-rate operation were limited
The H-1 cars are long retired, and we now have stations 2 km apart. The last time I raised this option at the TTC (as part of the debate on a subway car purchase), the reaction was nearly apopletic: running faster trains meant buying fewer new ones, and it is Toronto’s job to keep the plant in Thunder Bay running. Although the TTC agreed to take this option into account for future fleet planning, this never happened.
By now, “low rate” is the only thing people know, and it is quite possible that the newly-ordered Bombardier cars cannot operate in “high rate”, making this all a moot point. Getting more capacity by running trains faster is probably not a viable option, and in any event, until you deal with the terminal layouts, all “high rate” operation would do is to speed up the service and reduce future fleet requirements with, possibly, some offsetting maintenance and energy cost impacts.
Finally, if we add 40 percent to the capacity of the subway, we also add 40 percent to the pedestrian traffic through the stations. Several of our major stations would not be able to absorb such an impact because of choke points in stairways and escalators, and minor delays would produce badly congested stations much more quickly than today.
Moscoe raises one-person crews in connection with his plan to provide “Station Managers”. What is he thinking? If he wants to have Station Managers, just hire them. We should not have to wait until 2015 or later to have someone who will wander from station to station ensuring that escalators are running, that obsolete notices are torn down, that food spills are cleaned up, that garbage is cleaned away.
Just having someone to spot a problem is not enough: if an escalator is not working, who restarts it? Is there a mechanic on duty to check for problems and decide whether it requires repairs? If a platform needs to be cleaned, is there a janitor? What tasks does a Station Manager do on their own, and for what do they need other staff on call?
At any given time there are vastly more staff acting as conductors (“guards”) on trains than would be required to provide coverage of one Manager per five or six stations.
This is short-sighted budget manipulation at its worst: making major capital spending decisions based on a minor headcount avoidance (that’s HR-speak for “not hiring more staff”).
One Person Train Operation
If we move to one-person crews with ATO, the doors will be monitored from the front of the train, possibly with the assistance of one of the thousands of new video cameras the TTC plans to install.
One person crews have one huge drawback for fast turnarounds (see discussion about line capacity above). At a location where there is no step-back crewing (crews dropping back to a following train at terminals), then an operator will have to walk the entire length of a train to reverse direction. This will make turnback operations at pockets rather tedious, and dreams of well-oiled, minimum headway operations will go up in smoke.
[An aside: The new trains will have guards at the back of the train. I found this rather amusing considering that for years the TTC insisted they be close to the centre of trains for safety reasons (shortest possible view along the platform in either direction). Safety seems to be an elastic consideration at the TTC, stretched to suit the current policy directions.]
Yes, ATO can do this at a relatively small cost because we no longer require track circuits, relays, logic systems to be designed to deal with the idea that “ahead” and “behind” can be reversed. It’s a software change, not a hardware change.
However, this only solves one problem — how to dodge around a maintenance crew or other source of line blockage. It does not address a very basic problem: the power supply system is not designed to be shut off in only one direction. If you cut power from Bloor to Union, you do so on both rails. Since power is commonly turned off when work proceeds at track level, this will prevent bidirectional operation on the track that’s not being worked on.
Changing the power supply so that each rail can be powered independently is a very large job. Moreover, there are still certain types of maintenance that require access to both tracks at once or where the presence of trains on the “other” track would be dangerous for maintenance workers.
All Night Service
We are told that bidirectional operation is essential to allow all night service to co-exist with maintenance. I have already discussed some of the operational problems of this arrangement above, but that’s not all.
The frequency of service will be dictated by the largest gap between points where single-track operation is required. For example, there is about 4km between the pocket track north of St. Clair West and the next crossover opportunity at Lawrence West. This means that either we are going to bunch trains together to run a convoy through the single track section, or the headway must be wide enough to avoid conflicts. This is the same problem single-track railways face all over the world.
Are we going to operate all of the YUS and BD lines, or just truncated versions? Are we going to close selective stations? Will all-night bus services run into the stations or load at street entrances? How many station staff, security, janitorial, maintenance and other workers are required to keep these stations open and the trains running?
If trains ran, say, every 10 minutes on Bloor-Danforth, this would require 10 trains, or less if some stations closed. If we have one person crews, there will be far more people operating the system that driving the trains. These will eat up money that could be used to simply operate a far better surface night bus network.
Most importantly, what do we do about surface operations? Today, the night buses run fairly often, although we could argue for better service. They stop at many locations between subway stations. How attractive would all-night service be if it ran every 10 to 15 minutes and all of the minor stations were closed?
This whole scheme is a non-starter. If the TTC wants to move to Automated Train Control, then do it for its own sake and justify the cost. Some new technology is essential anyhow to replace the aging equipment dating back half a century to the opening of the Yonge line. This has been planned as a long, staged implementation as various generations of original signal equipment wear out.
But don’t piggyback a bunch of phony arguments about night service and station management onto the project so that it can be accelerated at great cost to cover the entire system.
This proposal is very badly framed, and I am astounded that Howard Moscoe hasn’t got the sense to smell the steaming mound of cow dung.