Crazy Transit Pitches

winstonoboogie said:
An automated system is going to maintain the ability for a dispatcher to cross-back a train at Harvard at any time, which requires keeping the track clear from the interlocking to the platform until the train has cleared the platform (northbound) or cleared the interlocking (southbound). The distance and speed from the platform to the interlocking at Harvard is much longer than standard for an automated interlocking (like Alewife, Park St., Ashmont, North Quincy Quincy Center, Quincy Adams, or Braintree on the Red)
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Why is it so important to keep the platform clear until the preceding train has left the interlocking (or vice versa)? A train can enter the platform and dwell at it while the interlocking is switched. If for some reason it's super-important to have off-schedule short-turns (which is one of the reasons I bring up organization here as more important than electronics), it's perfectly possible to switch a northbound train to the southbound platform for turnback even while the preceding train is dwelling at the northbound platform.
 
Alon said:
Why is it so important to keep the platform clear until the preceding train has left the interlocking (or vice versa)? A train can enter the platform and dwell at it while the interlocking is switched. If for some reason it's super-important to have off-schedule short-turns (which is one of the reasons I bring up organization here as more important than electronics), it's perfectly possible to switch a northbound train to the southbound platform for turnback even while the preceding train is dwelling at the northbound platform.
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If a northbound train is on the platform, it allows the dispatcher to route it back southbound from that track, which it couldn't do if the next Alewife train had already passed the interlocking and was committed to the route. Conversely, a southbound train won't have clearance to their platform until the previous southbound train has cleared the interlocking, as that gives the dispatcher the option to set up a route to cross a northbound onto the southbound, which they could not do if a southbound train was already committed to entering the southbound platform. Think about how the interlocking works at a terminal which has a much more standard short distance from the switches to the platform. A southbound train at Braintree would not pass through the interlocking until the previous southbound train had completed its move through the plant and was at the platform on one of the two tracks. That takes under a minute at Braintree, so it is not going to reduce capacity, but its the same idea.
 
winstonoboogie said:
If a northbound train is on the platform, it allows the dispatcher to route it back southbound from that track, which it couldn't do if the next Alewife train had already passed the interlocking and was committed to the route. Conversely, a southbound train won't have clearance to their platform until the previous southbound train has cleared the interlocking, as that gives the dispatcher the option to set up a route to cross a northbound onto the southbound, which they could not do if a southbound train was already committed to entering the southbound platform.
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Okay, so the MBTA dispatchers want to be able to decide on a minute's notice to tell passengers on a northbound train that they all have to get off because the train's going to terminate, even though it was signed as "Alewife" when they got on. And what's more, apparently the dispatchers can make this decision even after the train leaves the platform - in fact at any moment until it clears the platform - and that's why the following train can't enter the interlocking until the train leaves.

This is what I mean when I say "don't be helpless." Ask yourself just how important it is to be able to do these things before pronouncing 20 tph a hard limit independent of any signal system. Organization first. Then electronics. Only then concrete.
 
Alon said:
Okay, so the MBTA dispatchers want to be able to decide on a minute's notice to tell passengers on a northbound train that they all have to get off because the train's going to terminate, even though it was signed as "Alewife" when they got on. And what's more, apparently the dispatchers can make this decision even after the train leaves the platform - in fact at any moment until it clears the platform - and that's why the following train can't enter the interlocking until the train leaves.

This is what I mean when I say "don't be helpless." Ask yourself just how important it is to be able to do these things before pronouncing 20 tph a hard limit independent of any signal system. Organization first. Then electronics. Only then concrete.
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There is no place between Park and Alewife to quickly turn a train except Harvard. More likely scenario is train with a mechanical issue is nursed into Harvard, decision is made by inspector at Harvard to cross back (as the maintenance facility is back south along the line), and the train is then unloaded and reversed.

And to add more to the conversation, let's say a decision is made to retire the Harvard interlocking and make it a manually thrown switch which greatly reduces the ability to deal quickly with disabled and/or delayed trains in a long segment. Well, the layout at Alewife may still present a challenge with turning trains at a pace greater than 20 tph. It is only a two track terminal, and the distance from the interlocking to the platforms is not as great or on a sharp curve as at Harvard but it is greater than at Braintree, Oak Grove, or Forest Hills.

Back in the 1940s, the Red Line ran about 29-30 tph between Harvard and Ashmont on a block system with mechanical trip arms. Harvard and Ashmont both had separate northbound and southbound loading/unloading platforms: trains came in, unloaded, proceeded past the station to a three-track layup yard, changed ends there, proceeded into the opposite track, and then loaded for the return trip. That set up allowed up to five trains to simultaneously be at the terminal. In addition, Ashmont and Harvard both had large yards which could supply fresh trains into the lineups as required to maintain the headway. The three track layup yard set up at Harvard was maintained even when a temporary facility (Harvard/Brattle) was in use during the construction of the Northwest extension. Alewife however was built as a two track facility with a small underground yard to the north. Four car trains were the norm when it was designed, but plans were in the works to expand to six-car trains. At that time, six-car trains running 15 tph was thought to be more than enough expanded capacity to meet demand. Alewife is not set up to handle volumes like the old Harvard did; even now with the brief burst of 20 tph, it is not unusually in the peak of the peak for a train to sit outside of the interlocking at Alewife as both tracks in the station can be occupied. Don't count on signal upgrades to be the savior.
 
winstonoboogie said:
There is no place between Park and Alewife to quickly turn a train except Harvard. More likely scenario is train with a mechanical issue is nursed into Harvard, decision is made by inspector at Harvard to cross back (as the maintenance facility is back south along the line), and the train is then unloaded and reversed.
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On busy lines, trains don't turn at through-stations. New York doesn't randomly turn 4 or 5 trains at Bowling Green at rush hour, and it deals with mechanical issues by maintaining rolling stock to such standards that the MDBF is high enough that this doesn't happen routinely. Unless there's scheduled maintenance and a segment of the line is bustituted, no trains should ever turn at Harvard.

And to add more to the conversation, let's say a decision is made to retire the Harvard interlocking and make it a manually thrown switch which greatly reduces the ability to deal quickly with disabled and/or delayed trains in a long segment. Well, the layout at Alewife may still present a challenge with turning trains at a pace greater than 20 tph. It is only a two track terminal, and the distance from the interlocking to the platforms is not as great or on a sharp curve as at Harvard but it is greater than at Braintree, Oak Grove, or Forest Hills.
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Interlocking-platform distances don't really matter. First, 100 extra meters of distance to the interlocking adds maybe 8 seconds of travel time, so it makes a difference between 30 and 28 tph, not 30 and 20. And second, interlockings can be moved at several orders of magnitude less money than constructing equivalent capacity with a new subway.

What matters more is tail tracks. However, tail tracks do not need to be very long - 30 meters or so is enough on the Chuo Line at Tokyo Station, which runs 28 tph. The 7 in New York had maybe 100 at Times Square until the extension was built, ran 24 tph, and had its limiting factor elsewhere on the line. The L train in New York has no tail tracks at all at 8th Avenue, and was limited to 15 tph, but now has CBTC and can do 26 tph.
 
Alon said:
And second, interlockings can be moved at several orders of magnitude less money than constructing equivalent capacity with a new subway.

.
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There is a divider wall between the north and southbound tracks at Alewife in the segment between the interlocking and the platform, sure it would be cheaper than building a new subway to move the interlocking closer to the station, but it would not be an easy undertaking, especially if the tunnel is supporting part of the station complex/garage above. For a train making the adverse move into the station, it can take close to 2 minutes from the start of the interlocking to berthing the train at the station. As stated, maintaining the brief burst of 20 tph can sometimes be problematic with the present layout.
 
IIRC, there is no dividing wall on either side of Central. It would seem to make a lot more sense to put crossovers there to deal with disabled trains. Use the Harvard crossovers only when regular service is terminating there for whatever reason.
 
winstonoboogie said:
There is a divider wall between the north and southbound tracks at Alewife in the segment between the interlocking and the platform, sure it would be cheaper than building a new subway to move the interlocking closer to the station, but it would not be an easy undertaking, especially if the tunnel is supporting part of the station complex/garage above. For a train making the adverse move into the station, it can take close to 2 minutes from the start of the interlocking to berthing the train at the station. As stated, maintaining the brief burst of 20 tph can sometimes be problematic with the present layout.
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But only half the trains make the adverse move, which means that an almost-2-minutes travel time is not as big a deal. The limiting factor coming from the terminal is the dwell time (which can be sub-1 minute) plus the arithmetic average of the sum of the adverse and straight move.

A useful trick here is that an inbound and an outbound train can make the straight move simultaneously, and can both make the adverse move separated by only a few seconds. All it requires is that the train that occupies the interlocking second enter a stopping time after the train that enters first has left, and this is on the order of 10-15 seconds. If the inbound train is first, it does not need to be berthed when the outbound train leaves; it only needs to be clear of the interlocking.

Stopping times in the 15-second area seem low, but on running tracks they're not the limiting factor to capacity. Normally, the limit is stopping time plus dwell plus platform clearing time, and this is already more like 80 seconds, which isn't much less than the minimum headway that's achieved in practice, which has margins of safety. Reportedly some driverless systems can go down to 75, but this is with fast-accelerating, relatively short trains, reducing platform clearing time, and even so they don't actually do this in practice.
 
I think New England should build a network of Higher Speed Lines , speeding up travel to the main hub cities of New Haven , Worcester , Springfield , Boston , Providence , Concord , Portland , Manchester , Hartford , Stamford , Albany,etc... The Higher Speed Services would have hourly departures and run up to 125mph. Once the higher speed network is established , then a true HSR line running from Boston to NYC and along I-90 West to Buffalo should be built. The Network would be Electrified with the exception of a few lesser used corridors... I put them on a Map which is not done yet...

The Map

Knowledge Corridor Express - 20 Roundtrips
New Haven
Berlin
Hartford
Windsor Locks - Bradley International Airport
Springfield
Northampton
Greenfield
Brattleboro

Berkshire Express - 15 Roundtrips
Boston South Station
Boston Back Bay
Framingham
Worcester
Palmer
Indian Orchard
Springfield
West Springfield
Westfield
Pittsfield
Albany

Central Rail Corridor - 18 Roundtrips (Diesel)
New London
Mohegan
Norwich
Willimantic
Storrs
Stafford Springs
Monson
Palmer
Three Rivers
Belchertown
Amherst
Millers Falls
Brattleboro


Vermonter - 5 Roundtrips
Washington DC
Baltimore Penn Station
Wilmington
30th Street - Philadelphia
Trenton
Newark Penn Station
New York Penn Station
New Rochelle
Stamford
New Haven
Hartford
Windsor Locks - Bradley International Airport
Springfield
Northampton
Greenfield
Brattleboro
Bellows Falls
Claremont
Windsor-Mt. Ascutney, VT
White River Junction
Randolph
Montpelier
Waterbury
Essex Junction
St. Albans
Montreal

Cape Codder - 10 Roundtrips (May-September) & 2 Roundtrips (October-April)
New York Penn
New Rochelle
Stamford
New Haven
Old Saybrook
New London
Mystic
Westerly
Kingston
Providence
Taunton
Wareham
Buzzards Bay
Sandwich
Barnstable
Hyannis

Western Berkshire Access - 8 Roundtrips (April to Early November) & 2 Roundtrips (Mid November to April) (Electric to New Milford & Diesel to North Adams)
New York Penn
New Rochelle
Stamford
South Norwalk
Danbury
New Milford
Kent
Falls Village
North Canaan
Great Barrington
Houstonic
Lee
Pittsfield
Cheshire
Adams
North Adams

Cape Access - 8 Roundtrips
Worcester
Woonsocket
Pawtucket
Attleboro
Taunton
Middleborough
Wareham
Buzzards Bay
Sandwich
Barnstable
Hyannis

Eastern Link - 8 Roundtrips (Diesel)
New London
Norwich-Preston
Jewett City
Plainfield
Danielson
Putnam
Webster
Oxford
Auburn
Worcester
 
To go along with regional ideas, I'd like to bring up my idea of improved transit service to Worcester again. I brought it up back on page 124 here, but it got buried in-between a discussion of the red line.

This would make Worcester/Union Station the main hub of the station, with 3 rapid transit lines connecting there, as well as most bus routes and all 4 proposed commuter lines terminating there as well.

The proposed Rapid Transit map:

Acd4nVc.jpg


This would have a total of 5 lines, serving Worcester & 4 of its major suburbs - Auburn, Leicester's Cherry Valley area, Millbury, & Shrewsbury. There is also a stop on the Worcester/West Boylston border on the opposite side of the road from the 190 on & off-ramps there.

The proposed system would be an Automated Rapid Transit system. Each station capable of 6 car trains, but that capacity wouldn't likely be needed until decades into the future. Terminus stations would have loops constructed at ends instead of switchbacks - saving quite a bit of time by not changing ends. All layover yards would be underground with parking garages and/or retail at street level. (Picture Alewife with better road connections)

The core of the system - Union Station, would be fed from 4 commuter rail lines. These would connect downtown Worcester to Fitchburg & Leominster, Gardner, Providence, and Webster. Since west of Worcester is much more rural until you reach greater Springfield, (not exactly a good terminus for a reasonable commuter rail line - that's intercity territory) I decided to avoid going out that way on the B & A line with commuter rail. (Purple is the existing Framingham/Worcester line.)

Bo1HX40.jpg


This is a simple push-pull operation with signal, double-tracking, and bridge rehab/replacements where needed. Unlike the MBTA's system of high level boarding, I'd like to go low since these are still busy freight routes. With Providence however, high level is necessary - so something like how NJ Transit does it with two sets of doors would be needed.

I am slightly hung up as I have a park and ride facility in Oxford for commuter rail, and have another one in Auburn, just south of Sword St. Not quite sure what I'm going to do there yet.

And lastly, for in-fill, the bus network remains, along with a downtown shuttle streetcar.

33gGMax.jpg


Outside of that area, other regional transit authorities have jurisdiction (for example, Metrowest and Montachusett further east and north respectively, of the bus routes shown - although I am thinking of adding more Metrowest routes.
 
Nexis4jersey said:
Eastern Link - 8 Roundtrips (Diesel)
New London
Norwich-Preston
Jewett City
Plainfield
Danielson
Putnam
Webster
Oxford
Auburn
Worcester
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For the Eastern link, I'm not sure it would be good to stop in all 4 of the Mass. communities on that line. All of Auburn can easily access Union Station via 290, and Oxford could do the same, but some might want to go south to a station in Webster - which as it's more developed than the other 2 inbetween Worcester, it might make sense to keep a station in Webster, especially if you can get close to the downtown area.
 
WormtownNative said:
For the Eastern link, I'm not sure it would be good to stop in all 4 of the Mass. communities on that line. All of Auburn can easily access Union Station via 290, and Oxford could do the same, but some might want to go south to a station in Webster - which as it's more developed than the other 2 inbetween Worcester, it might make sense to keep a station in Webster, especially if you can get close to the downtown area.
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Some of those towns are limited stops with 6 roundtrip trains per day and a 2 car platform. Instead of the normal 20 roundtrip trains per and 4 car platform.
 
There's been this guy who keeps on showing up at stuff and pushing this nonsense. I've seen him several times already. They might actually be based out of Brighton.
 
Just looking at this at the very basic top level: The design as is right now is a non-starter from the get-go because it's non-ADA compliant.

Not to mention that PRT is the most ridiculous concept ever. If only we had a transportation mode/vehicle that could hold multiple groups of 2 people...
 
Ok, my Worcester Rapid Transit plans may be crazy, but holy sh*t this takes it to the next level.
 
BostonUrbEx said:
I could never pass up an opportunity to criticize PRT.

It's like monorails. Who keeps pushing this stuff?! :confused:
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Some Elon Musk wannabe who's got delusions of grandeur of giving a TED Talk full of narcissistic navel-gazing about "disruptive innovation". It's not done with the expectation that somebody will actually build anything other than a test demonstrator for people to gawk at. If they find a sucker willing to go full-retard, all the better.

https://www.youtube.com/watch?v=wJ5CbLnSjo0
 
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