Darwinkgo
Active Member
Should be in the technical parts of the JPO reports whenever they're developed. Whether we get a technical answer, or just a summary, who knows.
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- Thread starter ehlow
- Start date
roger1818
Senior Member
According to this article, for Montreal-Quebec while the plan is for 18 trains a day, only 10 will be on the north shore (and thus use the tunnel). So, if that article is correct (which is uncertain), that will likely be less than 1 train an hour. I also don't think there are any plans to increase frequency, as to do so would mean doubling the number of passing tracks (they will be spaced for a set departure interval, so the only reasonable option is to double the frequency, or at least half the standard departure interval).
Assuming the maximum capacity of REM is 40 trains a day, that is a minimum spacing of every 1.5 minutes. To insert a VIA train, it would leave 1.5 minutes after a REM train and then the next REM train would have to leave 1.5 minutes after that, which is 30 seconds later than normal, which really is not a big deal.
The only issue I can see is southbound, where VIA train would need to cross the northbound track twice, requiring more precise timing. It isn't impossible to deal with though.
Off peak, when the REM will be running fewer trains, all of this becomes a non-issue, so only a few trains a day require this extra effort.
kEiThZ
Superstar
REM interlining is just way too difficult. Those are some tight numbers to work with. Having two stations is not ideal. But Montreal wouldn't be the first city in the world to have two intercity rail stations.
Also, 10 trains on the northern route seems low. They could probably run this route hourly with at least 15 departures a day.
Also, 10 trains on the northern route seems low. They could probably run this route hourly with at least 15 departures a day.
Allandale25
Senior Member
^ I note that the article above is from 2018, so there is a possibility things could have changed since then or the JPL will provide an update when it's publicly released (fingers crossed it's publicly released).
roger1818
Senior Member
While I don't disagree with you regarding having two stations, I really think VIA will try to make this work, and I don't think it will be as hard as you seem to think. Off peak, REM will be running at much lower frequencies, so interlining will be easy. During peak, if VIA's 18 departures a day are split between the north and south shores, VIA could have most of the peak period arrival and departures use the south shore and thus don't need the tunnel.
For eastbound AM departures, they could have one departure use the tunnel in the morning before peak and then the next tunnel train after peak since it is when the train arrives at its destination that matters the most in the AM.
For westbound AM departures, they could try squeeze an arrival in before the peak, taking advantage of the shorter, more reliable travel times on the north shore, and the next one could be after.
For eastbound PM departures, they could have either have a train through the tunnel just before and just after peak (with a south shore train in peak), or they might try to squeeze one train in through peak, as northbound is easier to deal with and PM peak tends to be more spread out and peak transit frequencies tend to be lower to compensate (meaning a longer interval between departures).
For westbound PM departures, it is the departure time that is important, and a departure during peak wouldn't arrive at the tunnel until well after peak is over.
Interestingly, I just noticed that the article I previously referenced, says the REM will be "running every six to 12 minutes on the line." If that is the case, there will only be 5 to 10 trains an hour, less than half the 24 @jelbana said, and sharing will be easy.
crs1026
Superstar
^I don't know what kind of signalling system REM has specified, presumably a moving block system? Anyways, the critical constraint would be the braking capability of the new VIA equipment as compared to REM stock. The VIA train would have to hang back as far as needed to assure safe braking distance as the REM ahead makes its stops, and/or in an unplanned stop situation.
There might be a desire/need for the VIA train to "creep" rather than follow closely so that it does not have to come to a full stop behind the REM at each station. That, in turn, might affect the bunching of following LRV's if the line is at maximum capacity.
Also, all transit systems have to anticipate a "bunching" situation where one LRV is delayed and the next one is following on its block. Some margin of delay might be assumed as the LRV ahead may not be proceeding at the full rated speed.
What that means is that a VIA train might not fit neatly into a REM "slot" at 40 trains per hour - the gap might be a little longer. Probably not important outside of peak periods.
- Paul
There might be a desire/need for the VIA train to "creep" rather than follow closely so that it does not have to come to a full stop behind the REM at each station. That, in turn, might affect the bunching of following LRV's if the line is at maximum capacity.
Also, all transit systems have to anticipate a "bunching" situation where one LRV is delayed and the next one is following on its block. Some margin of delay might be assumed as the LRV ahead may not be proceeding at the full rated speed.
What that means is that a VIA train might not fit neatly into a REM "slot" at 40 trains per hour - the gap might be a little longer. Probably not important outside of peak periods.
- Paul
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roger1818
Senior Member
Thanks, I would certainly trust the horse's mouth more than a media report. The exact quote for the tunnel section from your reference seems to be:
I guess it depends how they define "peak hour" but avoiding that period should make it easy for VIA to use the tunnel.
kEiThZ
Superstar
Ummm. I would think VIA and REM will have the same peak hours.
Admiral Beez
Superstar
I’m looking to VIA‘s national service to return to normal. I’m thinking of this summer doing the Toronto to Vancouver run, but in style with a proper cabin. I did Toronto to Calgary in 1988 and slept in the empty luggage shelf.
kEiThZ
Superstar
Right. But why would you suggest they can avoid rush hour. That would probably be their highest fare time slots.
roger1818
Senior Member
I will reply with a quote from the post I referenced:
Not optimal, but better than your suggestion of VIA building a second terminal station (presumably north of Mount Royal).
I agree it would be optimal if they can use the tunnel during peak periods (without having to enlarge it for a third track). After all, there would likely only need to be 1 VIA train per "peak hour" (south/west bound in am and north/east bound in pm since the need to depart Montreal during the am peak and arrive during the pm peak is minimal and can be avoided). That is where my question of what their definition of 'peak hour' comes into play. If it is truly only 1 hour long, then it should be easy to avoid (they could have a train just before and/or one just after). If it is over 2 hours long, not so much.
robmausser
Senior Member
They actually dont let you do that anymore.
Source: me taking the Canadian in economy in 2014.
crs1026
Superstar
Update Document on the new equipment procurement:
- Paul
- Paul
Allandale25
Senior Member
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