More Toronto Rockets for the TTC

At its meeting on May 6, the TTC approved two add-on orders of Toronto Rocket subway cars.

  • 21 6-car trainsets to replace the H-6 fleet
  • 10 6-car trainsets to provision the Spadina subway extension to Vaughan

The unit cost of the first 21 sets is approximately $15.1-million, while the remaining 10 will cost about $16.3-million each.

These orders will follow the current TR car production at Bombardier’s Thunder Bay plant allowing continuous production at a lower price than if a small Spadina-only order were to be placed closer to the opening date in 2015.

Once these trainsets are delivered, the Yonge-University-Spadina line will operate entirely with TR trains, and the T1 fleet will be shifted to the Bloor-Danforth line.  (The Sheppard line will continue to use T1 equipment that will likely be stored on the YUS, but serviced at Greenwood Carhouse.)

The TTC’s subway fleet plan, presented as part of the 2010-2014 Capital Budget, foresees an eventual fleet of 69 trains on the YUS calculated as follows:

  • Existing service is 48 trains (T1 equivalent)
  • Add 3 for extension of the short-turn operation to Glencairn
  • Add 5 for growth and closer headways with Automated Train Operation (ATO)
  • Add 9 for extension of the short-turn operation to Wilson (when the Vaughan extension opens)
  • Add 1 for growth in each of 2019 and 2020

This gives a total of 67 “T1” equivalent trains.  At this point, the calculation gets a bit murky, but the outcome is roughly the same.  The TTC deducts the extra capacity of the TR trainsets to reduce train requirements by 7, although this very capacity bump is often mentioned as one of the reasons for buying the TRs in the first place.  However, additional effective capacity will be available through the implementation of ATO.

The TTC talks about this in terms of station dwell time, but I believe this is a red herring.  Passenger loading times have nothing to do with ATO.  What will be possible, however, is for trains to operate at a higher speed on those parts of the line where stations are further apart, and this will not require complete re-engineering of the signal system as would have been the case for the existing block signals.  Faster trips mean that the same number of trains can operate on a shorter headway and, thereby, increase capacity.

After allowing for spares at 13%, the total fleet requirement is 69 trainsets and this is the combined size of the three TR orders now on the books.

19 thoughts on “More Toronto Rockets for the TTC

  1. I suppose there must needs be a uniform fleet on YUS for the ATO plans to work but I’m still surprised to see the H6 cars being retired so soon. How old are they?

    Also, aren’t the TRs supposed to commence delivery this year?

    Steve: Yes, the TR’s should start appearing soon. Please see a later comment in this thread regarding the H6 replacement.

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  2. In the olden days, the Bloor-Danforth line used to get all the new trains first. Aren’t the H6s (the ones with the orange doors) still relatively new and in good shape? Those were the best trains — very quiet and smooth — much better than the T1s that came after them.

    Steve: The TTC did an evaluation of keeping the H6’s versus replacing them now given that the production line is already up and running. When the H6 replacement was first proposed, I suspected that the comparison may have given every possible break in favour of replacement given the TTC and Provincial desire to keep the production line going in Thunder Bay. Even so, the H6 fleet will be 30 years old in 2016-2019. Bombardier offered a lower price for an add-on order than the TTC might have received if these cars had been purchased separately. Moreover, the H6 fleet cannot be retrofitted with ATO, and without addition TR trainsets, the TTC cannot switch the YUS over to fully exploit the new signal system.

    This is an example of technology push where the decision to implement ATO influenced other purchases. We will see a similar issue on the BD line with the T1 fleet which does not reach its 30-year anniversary until 2025-2031. However, the TTC is talking about converting BD to ATO a decade earlier. One reason they are moving to an all-TR fleet on YUS is, it turns out, that retrofitting ATO to the T1’s is not cheap.

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  3. A couple of observations:

    That’s a lot of T1s for Bloor-Danforth and Sheppard. I wonder if some will be mothballed and parted out so the TTC can save money by not buying new spare parts for operating T1s. This also makes it look like parts are unavailable too, which is convenient. When they decide to want to retire all of the T1s in a couple of years, they can trot out the old ‘unobtainable parts’ excuse and point to some T1 carcasses and have it look believable.

    A spare ratio of 13% is interesting because one of the other reasons the TTC wanted to buy more Toronto Rocket cars was because they were billed as something like 50% more reliable than T1s. If true, this would imply needing a smaller spare ratio. How this 50% more reliable number was arrived at considering the TR prototype hadn’t been built yet when that was announced is anybody’s guess but with the capacity boost and subsequent cut in the number of trains they plan to put on the line, it is clear that creative accounting did not die with Enron and Arthur Anderson. It is alive and well at the TTC.

    ATO. Has a system been chosen yet? How can the TTC order subway cars with the equipment built in if the system (and by extension the equipment) has not been determined yet? Or is it simply the case that they forked over a lot of money to Bombardier for an engineering change order on those cars to have the propulsion system supplier leave provisions in place for ATO equipment to be added at a later date (i.e. expansion card slots in the control package etc)?

    Steve: Every generation of subway cars ordered by the TTC in my memory has been claimed to be “more reliable” than its predecessor, and the T1’s were supposed to deal with serious reliability problems on the H fleets. I have a hard time believing these numbers. What has happened in practice is that the TTC includes cars for future expansion in current orders, and retires older fleets more slowly than might otherwise occur, with the result that they can always sustain a much higher spare ratio than the wonderful claims for new cars.

    The actual fleet plans for both BD and YUS use a 13% spare factor. Obviously, they are expecting a comparable reliability for the T1 and TR fleets notwithstanding statements about the fabulously more reliable TR fleet. This leaves the TTC with a surplus of four T1 trains (24 cars) in the late 20-teens.

    One thing to remember about spares is the fact that a certain number of trains are out of service for routine inspections and overhauls that take place regularly, and there is a level below which it is almost impossible to reduce the spare ratio. Cars may be more reliable in the sense that they fail unexpectedly in service less often, but this does not necessarily translate to a comparable reduction in fleet requirements.

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  4. The H6 trains are about 20-25 years old now, so if you buy into the TTC’s stated service life for subway cars and streetcars of 30 years (streetcars were pegged at 40 until it became convenient to make them consistent with the subway cars) it becomes prudent to plan on replacing them now.

    Combine that with the fact that a better price can be obtained by placing an order now while the Toronto Rocket production line’s in full swing and the fact that the H6 trains are total junk despite their good ride quality, it makes sense to get rid of them sooner rather than later. This is one case where I’ll agree with the TTC on scrapping equipment prematurely.

    The H6s aren’t in very good shape. They had a problem when they were delivered where only two H6 pairs could be used in a train if they were separated by a pair of Hsomething-else or Montrealer cars in the middle. The propulsion system which is pretty much all the same Brush Electric Machines equipment as used on ALRVs never worked well. The trucks cracked and the entire H6 fleet had to have their trucks replaced. The motor alternator sets that generated the low voltage power on those cars were notoriously unreliable and were replaced with modified T1 inverters. Unfortunately, that didn’t help out the overall reliability of the H6 fleet as was hoped.

    In fact, the H6 cars were so bad when they were new, the TTC had to keep the Gloucester cars around about four years longer than they originally intended to and that’s probably about the only good thing that came out of the H6 cars. It’d make sense to junk the H6 trains first when the Toronto Rocket cars begin arriving instead of the H5s since they perform much better.

    Steve: Thanks for the technical history of the H6 fleet. These cars were not among the finest products to come out of Thunder Bay, but we cannot blame Bombardier. The plant was then under the direction, if that’s the right word, of the UTDC, another fine example of Queen’s Park’s meddlesome presence in Toronto’s transit system.

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  5. David O’Rourke wrote, “I suppose there must needs be a uniform fleet on YUS for the ATO plans to work…”

    Actually no, but as has already been pointed out by Steve, the H6s cannot be retrofitted with ATO and the T1s would be very expensive. As an example of a non-uniform fleet for ATO to work, just look at Vancouver’s Skytrain with both Mark-I and Mark-II ICTS/ART in their fleet. That said, I am told that their original plans to have mixed trains with both types of cars wouldn’t work because the ATO chokes on the different wheel diameters within the same train.

    On another point, TTC Passenger said, “…if you buy into the TTC’s stated service life for subway cars and streetcars of 30 years (streetcars were pegged at 40 until it became convenient to make them consistent with the subway cars)”

    I forgot that streetcars used to be pegged at 40 years! In the recent “more subways” hysteria, I heard the argument being made that “subways last longer”, to which I argued that LRVs last just as long, forgetting this little argument-strengthening point.

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  6. I was just wondering, if the YUS line is going ATO, wouldn’t it be possible to have no full length front cabs on the cars since there would be no driver or train guard needed? There are already many automated rapid transit lines out there where there is just a front window with a hidden control panel for manual operation (especially since some stations will start getting platform edge doors soon). It would be good if the front view was not all blocked off since there are many times where I will see kids sitting at the front to enjoy the view (along with the occasional transit nerd..).

    Steve: No, there will be no railfan window.

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  7. Re the H6s, UTDC management (mis-management?) of the plant in Thunder Bay was so bad that the workers went on strike for three months while the cars were being built to protest the deterioration of labour-management relations. Once the cars were put into service they had so many retrofits that at one point technicians were picking up replacement parts themselves and driving to Greenwood Yard to frantically replace the parts. Add to that a frame weakness that required all of the H6s then running to be pulled from service in July 1988 and you pretty much have the career of the H6s summed up. The TTC Equipment Dept. even reported that subway reliability dropped as the Gloucester cars were retired and replaced by the H6s. Who knows, the cost of refurbishing the power-hungry Gloucester fleet and keeping it running for the past 20 years might have worked to be less costly than all the money poured into those H6 clunkers!

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  8. A most interesting point has been raised here which is the service life of a streetcar/LRV as compared with that of a subway car.l

    A few weeks ago Chris Selly of the National Post, who is running to replace Michael Walker as city councillor, produced a statement in favour of subways over LRT. One of his arguments was that LRVs last only about 25 years without rebuilding while subway cars last about 60 years.

    I disputed these figures and insisted that essentially both should have an equal life span. A friend of mine looked up a TTC report which, in fact, stated that subway cars do indeed last a little longer than LRVs due to winter conditions and it placed this “fact” in the column for arguments in favour of subways over Light Rail. The only thing I could think of that would have any bearing at all would be the question of road salt damage. I could be wrong but I believe my friend was referred to that report by Sarah Thompson’s mayoral campaign.

    Now I am reading in the above posts that the TTC made an arbitrary change in the life span projections of both modes.

    Can anyone fill me in on what the truth is here?

    Steve: Yes, that was a Sarah Thompson factoid that has no basis in the real world. It is possible to make equipment last a very long time, but should this be attempted? I rode rapid transit cars on Boston’s Blue Line that were over 40 years old, but they only got out in the rush hour, and have now been retired.

    Toronto’s Peter Witt fleet dated from the 1920s, but some cars remained in service untril the early 1960s. Mechanically and electrically, they were simple vehicles. The PCCs were built to be easy to maintain, although somewhat more complex than a Witt, and the first of Toronto’s PCCs lasted about 30 years. They were done in not by falling apart (although comparable cars in Pittsburgh did just that thanks to lousy maintenance and an anti-streetcar policy), but by the massive reduction in the streetcar system following the BD subway’s opening in 1966.

    “Modern” equipment is harder to keep running because the technology becomes obsolete faster. A big problem with the CLRVs is that the electronics are hopelessly outdated, and if the TTC had decided to keep them, would have been replaced at a very substantial cost per car.

    Salt can affect vehicles that don’t run on the street by seeping in from snow tracked onto cars by riders. The SRT had this problem and all of the cars had to be rebuilt to repair salt damage to the subfloor. More generally, the lifespan of a vehicle body depends on how well built it was in the first place. Just look at the problem with buses. The industry treats them as throwaways after 12 years, and builds accordingly.

    Finally, the CLRVs were delivered from 1977 to 1981 and are, therefore, generally speaking 30 years old. Some of them will still be in service when the last of the new cars arrives in 2020. That sounds like a 40-year old streetcar to me.

    Meanwhile, on the subway system, the TTC spends an inordinate amount of time and money plugging leaks and fixing structural problems in tunnels. Just look at the North Yonge line where a poor design choice in the tunnel liners has triggered a multi-year job to correct the gradual “squashing” of the “round” tunnel by the weight of earth above it.

    The subway may physically last a century or more (many already have), but like any structure, you need to maintain it, and that costs money.

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  9. Rob Lubinski – I thought of another thing – there was probably some amount of chaos at Thunder Bay when UTDC moved ALRV production up there while H6 production was underway, including several incomplete ALRVs from Kingston, to make room for ICTS car production there. That can’t have helped either.

    One of the other things that likely contributed to the H6 cars becoming a rolling disaster was the lack of a meaningful prototype. Look at the way vehicle development’s been handled over the years: Converting a train of H2 cars into H3 cars to test chopper control was a good idea.

    Testing Hitachi’s equipment but then buying Garrett equipment for the H5 order wasn’t; there’s no validity to the testing when you go out and buy something else that’s unproven. H5 teething pains were to be expected. Luckily, those settled down to become pretty good cars.

    Buying the same equipment for the ALRV streetcar and H6 subway car orders to make a bigger volume order and reduce logistics costs through having a shared part supply was a good idea. Testing equipment from Brown Boveri Canada (you might recognize the name because they did the equipment on the Edmonton trolley coaches) on ALRV 4900 but then ordering untested, unproven Brush Electric Machines equipment for the production ALRVs and H6 subway cars was not a good idea. Unfortunately, the TTC didn’t get as lucky with the untried Brush equipment as they did with the untried Garrett equipment on the H5 trains, resulting in problematic fleets of streetcars and subway cars.

    Fortunately there were six CLRV prototypes to shake down. The CLRV fleet could have turned out really badly if they jumped right in to production without testing any prototypes, which is one of the most widely stated reasons why the Boeing LRV cars turned out to be such a disaster. Also, there was a T1 test train of six cars that didn’t have the interiors installed to shake down the equipment on those. It’s good to see Bombardier avoiding some risk by arranging for a test train of Toronto Rocket cars to be run in Toronto before production fully ramps up in Thunder Bay, likewise the three test streetcars. Hopefully these will be valid tests from an engineering point of view, with complete sets of equipment that’ll be used on the production fleets as opposed to test something form Manufacturer A but invalidate the whole exercise by ordering something form Manufacturer B without evaluation.

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  10. Steve writes:

    “What will be possible, however, is for trains to operate at a higher speed on those parts of the line where stations are further apart, and this will not require complete re-engineering of the signal system as would have been the case for the existing block signals. Faster trips mean that the same number of trains can operate on a shorter headway and, thereby, increase capacity.”

    Does this mean faster running through areas that are currently speed-restricted, or some kind of return to high-rate operation?

    Steve: If there is a speed restriction, it stays because that’s a function of track geometry, passenger comfort and safety. However, “high rate” or some equivalent of it can be used, for example, to climb hills faster and to run at top speed for a longer period. From my own experience, it shaves about 2 minutes off of the trip from Eglinton to Finch.

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  11. Steve, I know you speculated that the high-rate option may fall off the feature list for the TR cars. Is there any indication of what the performance of the TR cars will be? I presume the T1 cars still have the high-rate option.

    Also, you comment:
    “If there is a speed restriction, it stays because that’s a function of track geometry, passenger comfort and safety.”

    I was thinking that block-length speed restrictions are a pretty crude device, as they may extend considerably further than necessary depending on the location of the blocks versus the curve or gradient. Also, the best speed under the maximum only happens when the operator is cutting the timed signals very closely. Automatic operation may squeeze out a bit more speed.

    Not being familiar with the Scarborough RT (although I did ride it on its opening day), how are restricted speed zones due to workers at track level handled?

    Steve: The issue with speed timing signals is that they have to be set up for the acceleration profile trains are using. In high rate, the setup may be different. This requires far more work for fixed block signals than it does for ATO with moving blocks and gives the TTC the option of retiming the line based on higher performance cars. Of course, if they don’t do this (change the signals, or buy cars than can go faster), then all of their fleet plans are meaningless because they sized the fleet allowing for greater capacity of the trains, thereby reducing the number of trains available to serve the YUS. This only works if you make the fewer trains run faster to get the capacity back again.

    On the subject of work zones, these can be programmed into the ATO system. It is also possible to have work crews carry transponders that can “talk” to the signal system and inform it that they are present.

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  12. The big concern with changing fixed block speed timing signals is the emergency braking rate of the trains.

    The maximum speed on any given part of the subway line that you can set the signal timing for is determined by the distance needed for a train running at line speed to come to a stop with the emergency brakes applied. This distance has to be less than the distance from the wayside trip arm of the signal that’s protecting the next train ahead, to the rear of that train ahead.

    The result’s a physics problem for any given section of the subway: Given constants like the grade and maximum authorized speed on the line and the distance from trip arm to the rear of the next train and the lowest emergency brake deceleration rate of the different types of train that’ll be used and add a margin of safety, you’ll have to calculate what the highest speed possible before there’s a risk of collision.

    It’s the emergency braking rate that’s critical because it determines the design of the signalling system regardless of whether it’s moving or fixed block, and that’s what’s going to limit top speed. A higher acceleration rate’s good though because it shaves time off the wait for a train to reach that top speed when starting up from a station. To get the top speed up in order to make full use of the high-rate acceleration, the emergency brake rate’s got to come up too, so to that end, it might be a good idea to consider having track brakes on the subway trains.

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  13. I thought the acceleration profile of the trains only affected the placement of the Parallel/Series/Off controller markers and the partial/full/off braking markers. These are specifically what guide the operators to conform to the safe speed for a given block. The timed signals simply enforce the maximum speed. The maximum speed in a given track block is an absolute value that is not related to how quickly a train can achieve that speed by accelerating.

    On the topic of high rate, as I understand it the additional acceleration only kicks in after the maximum motor controller position for low rate is reached in the sequence. (In a camshaft controller the drum never rotates all the way to the end in low-rate. Electronic controllers simply emulate this behaviour.) The initial acceleration is automatically limited by sensors measuring the load the train is carrying at the time. This prevents the motors from being fed too much power and overheating.

    There are large portions of the lines where very little running time would be spent in these ‘upper registers’ at all and many areas where using them would lead to violation of the speed limits. I’ve only ridden one train where I know high-rate was switched on. The train was having some sort of difficulty that was making it run slow and was holding up the line a bit. The service person couldn’t figure it out, but as he was leaving the driver literally begged him to switch on the high-rate mode because the service person could get away with doing it. The driver seemed more an excited little kid about it than I did! The extra acceleration steps in the controller were quite noticeable when the train got fast enough to use them and then continued getting faster. I only really noticed it eastbound between Yonge and Sherbourne because of the length of that stretch.

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  14. And on the topic of brakes – I really wish our trains could get disc brakes. The tread brakes are always getting screeching loud and are often really rough-acting. Each train generation had it’s own braking character. The H4’s for example developed a horrible griding howl like dragging a heavy metal bin across concrete, but they always stopped smoothly and firmly. The H6’s seem to kick in too lightly but then shudder hard when finally stopping. The T1 design tried to make the brakes respond to the controller much quicker by injecting repeated strong bursts of air into the actuators instead of one long smooth fill. The brakes certainly kick in and out fast and firmly, but moving the controller back and forth while stopping makes the train jerk rather violently which is the least-pleasant experience of the lot. I’m afraid the TR’s will carry on this legacy as well as the awful ‘whooping’ of the AC motors.

    One memory that will stick with me is of an elderly woman complaining about the sounds of the T1 trains when they were brand new! She was tearing into a Supervisor about it and he admitted the TTC had received a large number of complaints.

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  15. TTC Passenger’s description about emergency brake timing is all good except that it ignores that with the system used by the TTC subway, there must be two blocks between a red signal with a raised trip arm and the back of the previous train, despite block lengths being a function of emergency stopping distance.

    When a train passes a signal, the signal turns red but the trip arm will remain down as long as both blocks on either side of the signal are still occupied. This prevents tripping caused when the third or fifth car of the train hits the trip arm. To ensure the trip arm does not raise until it is definitely past the signal, the block gap is usually a couple of metres past the signal. This characteristic of the system permits a key-by operation to pass a block signal at low speed when it is red. This used to be used at places like Bloor during rush hours to allow following trains to approach as close as possible to trains still in the station, but has been forbidden in the operating rules since the inquiry after the Russell Hill accident.

    All this means that the previous train must clear the second block beyond the signal before the signal may clear, despite the fact that a train being tripped can be stopped within the first block. A more modern signaling and trip arm system could substantially reduce the spacing needed between trains without the need to make the braking system work any faster.

    Steve: A clarification is needed here. There are two types of arrangements depending on whether a signal is a regular block signal (single aspect) or an interlocking signal (double aspect).

    For single aspect signals, the break in the track circuit happens ahead of the signal. For “key by” operation, a train creeps up to the signal, and this places the front truck of car 1 in the next track circuit. That signals the trip arm to drop, and it stays down until the train clears the END of that circuit (ie the following signal). The reason for the “key by” being banned is that once a train has keyed by a single red, the next red may not have a raised trip arm depending on the location of the preceding train.

    For double aspect signals, the break in the track circuit is right at the signal and there is no provision for automatic key by. If the signal clears, the trip arm will stay down as long as the train occupies the preceding block (the one before the signal), but the arm will go up immediately after the rear truck of the last car is off of that block.

    Operators can “sneak by” a single red if the preceding train is very close ahead because “train 1” will hold the trip arm down for “train 2”. However, at a double red, the signal circuits can detect the fact that this is really two trains close together, and the trip arm will rise between them. Many years ago I was on a train doing just this sort of move, following very close to the train ahead (yes, extremely unsafe), and it got as far as the first interlocking signal at which point the trip arm did its work.

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  16. I would further clarify that key-by is still possible at automatic block signals (any signals that don’t have an additional “X-number” which represents their control lever on the interlocking control panels). This movement does however require permission from Transit Control and is only used when there is a problem with a particular signal not clearing when it should.

    The one exception to this arrangement is in the southbound tunnel between St. Clair West and Dupont Stations (site of the Russel Hill crash). All of the automatic block signals on this stretch have been modified to require a “Manual Key-by” where the operator has to stop the train at the signal and reach out the window for a lever that causes the trip arm to lower. These signals now have a sign with a letter “M” which I assume stands for “Manual”. This is similar in function to the rarely-used manual key-by levers at all interlocking (“X-number”) signals which must be used when faced with a solid amber aspect instead of the flashing “Automatic Key-by” indication.

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  17. I would like to thank Steve for adding the clarification to my comment. I sometimes forget that not everyone reading knows the difference between block (single) and interlocking (double) signals.

    I also made the mistake of saying the block gap (break in track circuit) was a couple of metres after the signal/trip arm, when I meant to say that the signal/trip arm were a couple of metres after the gap. Of course, for those picky about wording, I should have said that the gap was a couple of metres “in advance” of the signal. 😉

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  18. TTC Passenger says:
    May 21, 2010 at 3:41 pm

    “The big concern with changing fixed block speed timing signals is the emergency braking rate of the trains.

    “The maximum speed on any given part of the subway line that you can set the signal timing for is determined by the distance needed for a train running at line speed to come to a stop with the emergency brakes applied. This distance has to be less than the distance from the wayside trip arm of the signal that’s protecting the next train ahead, to the rear of that train ahead.

    “The result’s a physics problem for any given section of the subway: Given constants like the grade and maximum authorized speed on the line and the distance from trip arm to the rear of the next train and the lowest emergency brake deceleration rate of the different types of train that’ll be used and add a margin of safety, you’ll have to calculate what the highest speed possible before there’s a risk of collision.

    “It’s the emergency braking rate that’s critical because it determines the design of the signalling system regardless of whether it’s moving or fixed block, and that’s what’s going to limit top speed. A higher acceleration rate’s good though because it shaves time off the wait for a train to reach that top speed when starting up from a station. To get the top speed up in order to make full use of the high-rate acceleration, the emergency brake rate’s got to come up too, so to that end, it might be a good idea to consider having track brakes on the subway trains.”

    But if you have ATO with a moving block system then you can get closer to the train in front. With the fixed block system you always have to have at least two full blocks between trains so this can go up to 2.99 blocks until the end of the train clears the block. With moving block you can have the train closer and still have room to stop. Since subways are not subject to black rail from having ice or leaves and rain making them greasy then track brakes are not necessary. In the few open cut sections where this may be a problem you can have the possibility built into the program and just tell it when there are black rail conditions.

    Kristian says:
    May 22, 2010 at 2:03 am

    “I thought the acceleration profile of the trains only affected the placement of the Parallel/Series/Off controller markers and the partial/full/off braking markers. These are specifically what guide the operators to conform to the safe speed for a given block. The timed signals simply enforce the maximum speed. The maximum speed in a given track block is an absolute value that is not related to how quickly a train can achieve that speed by accelerating.

    “On the topic of high rate, as I understand it the additional acceleration only kicks in after the maximum motor controller position for low rate is reached in the sequence. (In a camshaft controller the drum never rotates all the way to the end in low-rate. Electronic controllers simply emulate this behaviour.) The initial acceleration is automatically limited by sensors measuring the load the train is carrying at the time. This prevents the motors from being fed too much power and overheating.”

    In many DC motor applications the high range feature provided for the ability to reduce the number of field windings in the circuit. This reduced the back emf and allowed the motors to reach a higher rpm. With AC motors I assume that high range just allows the maximum frequency of the induction motors to go higher. Squirrel cage motors do not have the large mass of armature windings that need to be cooled and are not as susceptible to over heating and motor damage.

    Kristian says:
    May 22, 2010 at 2:18 am

    “And on the topic of brakes – I really wish our trains could get disc brakes. The tread brakes are always getting screeching loud and are often really rough-acting. Each train generation had it’s own braking character. The H4’s for example developed a horrible griding howl like dragging a heavy metal bin across concrete, but they always stopped smoothly and firmly. The H6’s seem to kick in too lightly but then shudder hard when finally stopping. The T1 design tried to make the brakes respond to the controller much quicker by injecting repeated strong bursts of air into the actuators instead of one long smooth fill. The brakes certainly kick in and out fast and firmly, but moving the controller back and forth while stopping makes the train jerk rather violently which is the least-pleasant experience of the lot. I’m afraid the TR’s will carry on this legacy as well as the awful ‘whooping’ of the AC motors.”

    If the system is set up properly the majority of the braking should be done by regenerative braking and not by the tread break. With AC motors it should be possible to use motor breaking to get the train down to less than 4 mph. If the tread brakes are squealing then the system is not set up correctly. Disc brakes should be unnecessary if the system is set up properly.

    With regards to the idea of spare ratio I seem to remember that after the fire at Union that destroyed 6 G cars after the University Subway opened that for a couple of years the TTC only had 6 spare Gloucester Cars during the peak times during the non summer months. This meant that the Montreal cars were in use during every rush hour for 10 months of the year. I believe that in the summer one train was removed from service so the M cars had to get their maintenance on weekend or in the summer, but the trains and their controllers were much simpler in those days.

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  19. Charles Wheeler in his 59 page report (December 2008), page 32 I believe, states.

    “Unless we get the dwell time to 30 seconds consequetively, we cannot add any trains with ATO”

    He further states “The present dwell is 60-90 seconds at Yonge & Bloor in rush hour”.

    If this is so, how in the world will ATO benefit if there is no capacity improvement unless you can have increased train through putting taking place?

    Steve: The emperor’s new clothes are embarrassingly threadbare some times. The TTC’s plans for increased capacity keep bumping into limits they didn’t think about. They want that Richmond Hill subway no matter what it does to the rest of the system.

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