Regional Rail (RUR) & North-South Rail Link (NSRL)

It says 1 powered car can pull 2 cars and no locomotive. I wonder if this would work good if we bought these to have a smaller trainset on fairmount vs dmus. The emu’s should be able to accelerate faster and much better headways.
 
It says 1 powered car can pull 2 cars and no locomotive. I wonder if this would work good if we bought these to have a smaller trainset on fairmount vs dmus. The emu’s should be able to accelerate faster and much better headways.


Any EMU beats the living snot out of a DMU, for simple reason of not needing to lug around engines and a full tank of fuel. Physics of mass really doesn't allow for closing that gap meaningfully.


DMU's might be a northside consideration where electrification is going to be later-arriving, but no question if you want Fairmount done right you're stringing up wire and not pussyfooting about it.
 
Please help with some definitions -- MLV and K-car?


MLV = MultiLevel Coach...Bombardier bi-level coach that NJ Transit and a few others use. Has 2 x 2 seating.



K-car = Kawasaki bi-level...the T's and MARC's bi-levels made by Kawasaki with clones by Rotem. Has 3 x 2 seating.
 
The problem with the current NJT Bombardier rolling stock is that there are long dwell times because of poor customer flow.

Each car has 4 doors on each side, but because of how close one of the doors is to the narrow stairs, the second pair (in the vestibule) is essentially useless.

The most popular door is narrow, only one person in or out at a time.

The stairs are narrow, causing congestion, especially when baggage is involved.

NJT has lost a lot of speed at the expense of capacity. This really bit them in the ass when they foolishly used the bilevels during the superbowl instead of the single levels with 3 useful doors.

However, some of these issues COULD be fixed. Removing ~2 seats at each end would allow the stairs to be wider, improving flow. Moving the door back and making it much wider could then allow for people to get on and off at the same time, and split up into two lines (for up and down).

Hopefully this order addresses some of those issues.
 
The problem with the current NJT Bombardier rolling stock is that there are long dwell times because of poor customer flow.

Each car has 4 doors on each side, but because of how close one of the doors is to the narrow stairs, the second pair (in the vestibule) is essentially useless.

The most popular door is narrow, only one person in or out at a time.

The stairs are narrow, causing congestion, especially when baggage is involved.

NJT has lost a lot of speed at the expense of capacity. This really bit them in the ass when they foolishly used the bilevels during the superbowl instead of the single levels with 3 useful doors.

However, some of these issues COULD be fixed. Removing ~2 seats at each end would allow the stairs to be wider, improving flow. Moving the door back and making it much wider could then allow for people to get on and off at the same time, and split up into two lines (for up and down).

Hopefully this order addresses some of those issues.

New order's supposed to make changes to the vestibule layout and feature wider doors to correct some of those flaws. The linkied video makes brief mention, but it's anybody's guess what that'll mean on the shipping product since it's so early in design. Does appear that complaint isn't falling on deaf ears, FWIW.

Ordering with 2 doors per side instead of 4 has been an order option since Day 1, as Montreal's fleet of MLV coaches is like that. NJT did the extra doors to have one set designated for high-level platforms and one set for lows so traps don't have to be flipped constantly by the conductors. If it created more space for flow ordering the 2-per-side door config with a sufficiently wide door similar to the T's bi's would suffice. After all, if they don't want to keep flipping door traps they should start raising more platforms; NJT seems to use its MLV door config as an agency excuse to let three-quarters of its platforms rot non-accessible.
 
Sullivan would be ideal for OL and bus connections. Union might be an acceptable second choice if Sullivan isn't possible for some reason. Both would be great, but maybe a bit much. If it hit both Orange and Green, then the only people who would NEED a NS bound train would be the people who don't make a subway connection there.

In addition to a Sullivan commuter rail platform enabling bus and Orange Line transfers, adding a Green Line branch out to Sullivan and the casino might make sense. Multiple branches past the casino might also make sense, including a branch stopping at all the Chelsea SL3 stops, possibly a branch stopping at the future and former Chelsea commuter rail stop and then continuing to Suffolk Downs, and possibly a branch continuing from the casino to Sweetser Circle and then Revere Beach Parkway and US 1. If there end up being three Green Line branches north of the casino and Sullivan, it might make sense to continue one of those branches to Lechmere, North Station, Park St, etc, a second to the Grand Junction (including Kendall) and BU West, and the third branch to Somerville's Union Sq, Porter Sq, and the Watertown Branch.

If Newburyport / Rockport passengers could transfer to both the Orange Line and Green Line at Sullivan, perhaps continuing those Newburyport / Rockport trains to Porter for Red Line transfers instead of sending them to North Station would make sense.
 
New order's supposed to make changes to the vestibule layout and feature wider doors to correct some of those flaws. The linkied video makes brief mention, but it's anybody's guess what that'll mean on the shipping product since it's so early in design. Does appear that complaint isn't falling on deaf ears, FWIW.

Thats very good news.

Ordering with 2 doors per side instead of 4 has been an order option since Day 1, as Montreal's fleet of MLV coaches is like that. NJT did the extra doors to have one set designated for high-level platforms and one set for lows so traps don't have to be flipped constantly by the conductors. If it created more space for flow ordering the 2-per-side door config with a sufficiently wide door similar to the T's bi's would suffice. After all, if they don't want to keep flipping door traps they should start raising more platforms; NJT seems to use its MLV door config as an agency excuse to let three-quarters of its platforms rot non-accessible.

Like the MBTA, NJT has no plans to make everything high floor any time soon, so the extra vestibule doors with traps are needed.

I can only think of a couple in the timeline. One of them is Perth Amboy, which was a 4-track station. They plan on making it high floor by permanently blocking the ROW of the 2 outer tracks.

Real long-term thinkers over there.
 
Do the bridge clearances in the system permit running bilevel cars under catenary? Obviously the Providence Line is OK in this regard, but what about the others?
 
Do the bridge clearances in the system permit running bilevel cars under catenary? Obviously the Providence Line is OK in this regard, but what about the others?

Clearances are pretty well-documented systemwide by what freight car 'plate' size a linear route will accept, including on the lines that carry no freight. 25 kV wire then takes +2.5 ft. of additional electrical clearance above the car roof to safeguard arcing potential.

With those facts in mind, it's verifiable today that all lines are OK as-is for 25 kV wire over a T bi-level except for:

  • (verifiable) Grand Junction Branch, Cambridge. Offending structure: Memorial Dr. overpass.
  • (*maybe*) Worcester Line, Boston. Offending structure: Beacon St. overpass.
Worcester is a "Plate C" restriction east of Beacon Park to SS. But so is the very much wired NEC all points north of Readville. The Beacon overpass is a razor-thin miss...no more than a few inches. Can't undercut because of proximity to Yawkey Station and the Muddy River bridge, but notching the bridge may work because the discrepancy is so slight. This is an extremely minimal concern for RER; the fix should be simple.

Grand Junction is a "Plate B" restriction--tightest on the system--and a big miss. Can't drop the railbed because of close proximity to the Charles bridge, can't raise Memorial Drive because the road's already got a wicked hump in it over that span. Possible solution is to have an unpowered insulated section of wire under the bridge that trains coast through (a sort of last resort for small overpasses like this which have zero give). But that assumes that a potential bi-level EMU has pantographs that could squeeze down far enough to make it through that insulated section. At any rate, northside's going to trail southside electrification by many years so not something to worry about up-front. Grand Junction is completely fine for Urban Ring electrification, because trolleys are obviously shorter and 600 V rapid transit electrification is only 2% as strong as 25 kV.


There's obviously a much more complicated scene for freight clearances under-wire as some lines have federally protected freight height allowances, and that's where all the cost & labor of raising bridges or undercutting track is going to be spent. Vastly bigger $$$ for that on the northside compared to southside, however.
 
Thanks as always for the high quality info.

Is it fair to say that the whole mem drive overpass there is overdue for a major reconstruction anyway? (Anyone who has driven over or under it in the last 15 or so years will understand...)

And I understand that the boathouse and the adjacent parking lot entrance just to the east are probably constraints on a longer/taller approach, but probably solvable?
 
F-Line,

Sick info last few weeks, months......

It's a real pleasure to read these incredible posts. :D
 
Any EMU beats the living snot out of a DMU, for simple reason of not needing to lug around engines and a full tank of fuel. Physics of mass really doesn't allow for closing that gap meaningfully.


DMU's might be a northside consideration where electrification is going to be later-arriving, but no question if you want Fairmount done right you're stringing up wire and not pussyfooting about it.

I recently read that for low-speed, adhesion-limited acceleration (ie up to maybe somewhere in the range of 30mph) DMUs and EMUs are pretty comparable, and far superior to anything hauled by a locomotive, even an electric locomotive. When adhesion limited, the extra weight of the diesel motors is offset by the extra traction that the extra weight provides.

It is for higher-speed acceleration where the greater power-to-weight ratio of EMUs is the biggest benefit. In other words, to take advantage of the better high-speed acceleration of EMUs, station spacing must be more than some minimum. Using lighter, european-style alternative compliance rolling stock would push the transition from adhesion-limited to power-limited acceleration to a faster speed, meaning that ligher vehicles (given the same number of powered axles) cause EMUs to lose more of their advantage in comparison with DMUs.

I don't know what the threshold is in terms of spacing where the EMU advantage disappears, but it does decrease when the stations are very close together. Fairmount does now have pretty closely spaced stations by commuter rail standards (average of about 1 mile) but I suspect the distance where the EMU advantage disappears is probably a good bit shorter than that (Maybe a quarter mile perhaps?)

Given that the EMU advantage decreases with very long station spacing (since most of the time is spent cruising at speed) and very short spacing (because of the traction problem above) it would be an interesting optimization problem to calculate the station spacing where EMUs provide the greatest advantage.

Of course there are other advantages to EMUs as well in terms of noise, pollution, operation in tunnels, maintenance costs, and perhaps fleet uniformity, but it is an interesting question nonetheless.
 
I recently read that for low-speed, adhesion-limited acceleration (ie up to maybe somewhere in the range of 30mph) DMUs and EMUs are pretty comparable, and far superior to anything hauled by a locomotive, even an electric locomotive. When adhesion limited, the extra weight of the diesel motors is offset by the extra traction that the extra weight provides.

It is for higher-speed acceleration where the greater power-to-weight ratio of EMUs is the biggest benefit. In other words, to take advantage of the better high-speed acceleration of EMUs, station spacing must be more than some minimum. Using lighter, european-style alternative compliance rolling stock would push the transition from adhesion-limited to power-limited acceleration to a faster speed, meaning that ligher vehicles (given the same number of powered axles) cause EMUs to lose more of their advantage in comparison with DMUs.

I don't know what the threshold is in terms of spacing where the EMU advantage disappears, but it does decrease when the stations are very close together. Fairmount does now have pretty closely spaced stations by commuter rail standards (average of about 1 mile) but I suspect the distance where the EMU advantage disappears is probably a good bit shorter than that (Maybe a quarter mile perhaps?)

Given that the EMU advantage decreases with very long station spacing (since most of the time is spent cruising at speed) and very short spacing (because of the traction problem above) it would be an interesting optimization problem to calculate the station spacing where EMUs provide the greatest advantage.

Of course there are other advantages to EMUs as well in terms of noise, pollution, operation in tunnels, maintenance costs, and perhaps fleet uniformity, but it is an interesting question nonetheless.

Problem is that the DMU buying options the T was previously considering were not at all lightweight. They were evaluating the somewhat porky full FRA-compliant Nippon-Sharyo model adopted by SMART & Union-Pearson Express for the Fairmount Line, because there was no way to sidestep freight track occupancy @ Readville. Ditto on the entire northside where freights live right up the gut of the terminal district moving around Boston Engine Terminal and serving Boston Sand & Gravel.

It's not clear if the revised FRA crashworthiness guidelines would allow for a Stadler GTW, a more appropriate lightweight reference model, to finally be purchased and deployed as-is and not require individual waivers for each line deployment (which we were never able to get because of our pooled terminal districts). It would substantially brighten the chances of DMU deployments if the GTW lineup got that blanket blessing, because it's fairly generic and well-established. But as of 2019 it's still sitting in the land of service waivers and not something the T can buy.


That brings us to the sobering reality the T has to contend with for advancing the RER study recs: the market for DMU's is absolutely wretched right now. Buy America has proven to be a huge limiting factor for that vehicle type taking off because most DMU procurements are extremely small...half-dozen to dozen units on-average. And the manufacturers just aren't making enough money assembling units at pop-up factories when EMU orders past and present can run 40-500 units a pop. Nippon-Sharyo has taken a big step back after it melted down on its Amtrak contract for bi-level coaches and was fired with penalties; it's no longer actively pushing its DMU product as it tries to do damage-control to its corporate rep in the fallout from the Amtrak debacle. And there's been a little bit of a bubble burst in terms of transit proposals utilizing DMU's being mothballed, changing focus, or stalling out from lack of advancement compared to 2012-15 when it was hyped as the "it" mode.

So there's a bit of a logistical conundrum here in that a vehicle market that was supposed to be heating up by 2018-20 has counterintuitively gone ice-cold...due to factors that don't have much at all to do with vehicle tech, but more an unfortunate intersection of business cycles. If the T wants to act, they literally have a better chance of acting by making a go-for-it decision on wiring up Fairmount + Riverside (the most extra service you can chain off a fully-expanded Sharon substation), and playing make-a-deal with NJ Transit for some of those MLV EMU 'slush' options. Then running the two intra-128 services, the Providence Line, and RIDOT intrastate off it. It's somewhat of an incredible turnabout from the Request for Proposals from 3 years ago where we thought we were getting some Nippon-Sharyo DMU's, but change in market conditions and availability of laundered options from somebody else's 800+ unit Bombardier electric contract will do it.

I hold out hope if it gets unshackled from regs that the Stadler DMU's can be a viable northside option for the 128-turning lines, since electrification is later-coming up there. But on the southside I'd rather they not even bother when a substantial pool fleet of EMU's can be amassed faster than it would take to do a comprehensive shopping search for DMU's in a down and Buy America-hostile market for those vehicles.
 
Do you guys think if we were going to “go for it”... blue to riverside would be a better idea? Either by way of the esplanade/storrow or tunnel under Beacon since blue and green both use overhead wires and it would make a ton of sense to connect to red at mgh then continue on to the back bay where no other options have existed yet then under Kenmore and on to Riverside. Eventually the Lynn extension would create a blue line consisting of Lynn to Riverside which seems like the ideal option vs orange to Riverside. Everything has hurdles and the track gauge is one, but I think if were gonna do it do it right. Then the Orange can be extended to Needham heights and Readville to meet up with whatever ends up on the indigo line some day and allow much better headways on the Needham line.
 
Do you guys think if we were going to “go for it”... blue to riverside would be a better idea?

My understanding is that it's important to maintain the D for the Green Line because the Riverside yard is absolutely necessary for the entire GL system.

I'm sure F-Line or another of our transit systems experts could speak to it more.
 
...and there are a lot of grade crossings in Needham that blue cant do, plus a lot of the stations rely on pedestrian track crossing.
 
Do you guys think if we were going to “go for it”... blue to riverside would be a better idea? Either by way of the esplanade/storrow or tunnel under Beacon since blue and green both use overhead wires and it would make a ton of sense to connect to red at mgh then continue on to the back bay where no other options have existed yet then under Kenmore and on to Riverside. Eventually the Lynn extension would create a blue line consisting of Lynn to Riverside which seems like the ideal option vs orange to Riverside. Everything has hurdles and the track gauge is one, but I think if were gonna do it do it right. Then the Orange can be extended to Needham heights and Readville to meet up with whatever ends up on the indigo line some day and allow much better headways on the Needham line.

That doesn't really address the same needs and Regional Rail or NSRL, so its hard to say if it is "better." My understanding is that RR or RR+NSRL will have massive impact on suburb-CDB commuting patterns and on town/small-city centers across eastern Mass. I see Blue-eats-D (if it is even possible) to primarily improve things for a much smaller number of urban and inner-suburban residents.

I think the improvements planned for the Green Line - Type 10's, stop consolidation, signal priority, etc - will greatly improve service for all Green Lines and will hit the D-Line first. I suspect the reason Blue-eats-D never never happened in the past is because it isn't that impactful.
 

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