General MBTA Topics (Multi Modal, Budget, MassDOT)

Re: Driven By Customer 'Service' Parte Dos

Ron Newman said:
Does GPS work underground?
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No. They can do this on Blue/Red/Orange because the track circuits that fire the signal system can sense the position of trains by measuring strength of electrical pulses through the running rails. That's how Maverick has had that light-up train board on Blue for over a half-century now. Green can't do that. That relegates them to:

1) Signal repeaters in the subway to maintain GPS underground. Similar to the cellular repeaters they have set up, but varying signal strength is probably gonna make that a glitchy operation they have to test for a long time before going live.

2) RF tags. Same as the tags that trigger the auto-stop announcements, but set to a different radio frequency for position tracking. Reliable and cheap, but it's not 'live' tracking because the train has to pass a transponder to ping its position so the travel times are going to be much more approximate and more likely to be wrong (e.g. if the train has to stop in between RF tags, the calculated timing between tags in obviously going to be inaccurate).
 
Re: Driven By Customer 'Service' Parte Dos

F-Line to Dudley said:
No. They can do this on Blue/Red/Orange because the track circuits that fire the signal system can sense the position of trains by measuring strength of electrical pulses through the running rails. That's how Maverick has had that light-up train board on Blue for over a half-century now. Green can't do that. That relegates them to:

1) Signal repeaters in the subway to maintain GPS underground. Similar to the cellular repeaters they have set up, but varying signal strength is probably gonna make that a glitchy operation they have to test for a long time before going live.

2) RF tags. Same as the tags that trigger the auto-stop announcements, but set to a different radio frequency for position tracking. Reliable and cheap, but it's not 'live' tracking because the train has to pass a transponder to ping its position so the travel times are going to be much more approximate and more likely to be wrong (e.g. if the train has to stop in between RF tags, the calculated timing between tags in obviously going to be inaccurate).
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Theres another option which I proposed on the rail forum...

1) Purchase video cameras and image recognition software.
Nothing expensive - all that's needed is the ability to see the letter in the roll sign of the trains. A black and white 1980s blockbuster security camera and a 1994 packard bell could process the data, as so little is needed. Obviously, you can get better with todays technology for bargain prices.

2) Install said cameras (maybe 50 total) in the subway, at predefined spots.

3) Wire cameras to previously mentioned centralized packard bell (a Dell will do as well).

Now the system knows that at 19:04 a B just passed Kenmore and at 19:05 a D passed Copley and a C was at Arlington etc.
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GPS for above ground of course.
 
Re: Driven By Customer 'Service' Parte Dos

I don't understand why they don't install more AVI readers. There's only 35 or so right now. Put a bunch out and get a better idea where things are.
 
Re: Driven By Customer 'Service' Parte Dos

It's just pathetic that they continue to invest so little in the most-used line of the entire system. I get it: people have had to wait and wonder when the next Red, Orange, or Blue train will arrive but at the end of the day that is far, far less annoying than having to wait for a specific train to one of three or four destinations (depending on direction).

Not to mention, relying on the manual tracking for scheduling is such an abomination it's really no wonder they can't seem to ever get it right.
 
Re: Driven By Customer 'Service' Parte Dos

http://www.boston.com/yourtown/news/downtown/2012/12/mbta_activates_train_arrival_c.html

24 new stations are getting the countdown clocks by early 2013. The article includes a list of the additional stations.

Orange Line:
Oak Grove
Malden Center
Wellington
Stony Brook
Green Street
Forest Hills

Blue Line:
Wonderland
Government Center
Bowdoin

Red Line:
Alewife
Davis
Porter
JFK/UMass
Savin Hill
Fields Corner
Shawmut
Ashmont
North Quincy
Wollaston
Quincy Center
Quincy Adams
Braintree
 
Re: Driven By Customer 'Service' Parte Dos

OK, so they decided that re-extending service to Heath was worth a small drop in service frequency on the E-line.
 
Re: Driven By Customer 'Service' Parte Dos

Ron Newman said:
OK, so they decided that re-extending service to Heath was worth a small drop in service frequency on the E-line.
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It's more like...reversing directions at Brigham is a royal P.I.T.A., and it takes them doing it regularly for a spell to institutionally remember why the staff hates having to turn back there. The track switches there are hand-throw...meaning the rear-car operator has to get out of the train with this big heavy bar/wrench thing, throw the switch, front-car operator crosses the train over, reset the switch, hop back onboard. They end up being habitually late on the schedule because of all that fussing, and get really surly when they have to get out and do that walk of shame in bad weather. And when it's a heavy crowd (Sox game, move-in weekend at NU, etc.) where they really need to stay on-schedule, they end up having to station a field inspector there all day to throw the switch for them...which ends up costing more money than cutting the line back saves.

They go through this every time. The rush-hour Brigham short-turns never seem to last long. The service cutbacks never seem to last long. The field staff revolts, and management backs off when the riders are barking at them on one side and their own staff are barking at them on the other side.


No long-term memory whatsoever. And they won't pay to install automatic switches at Brigham, so they don't even have the conviction to follow-through all the way on their passive-aggressive political causes either. So this scene repeats itself every few years and gets rolled back every time just as fast.
 
Re: Driven By Customer 'Service' Parte Dos

Also remember the accident. I think it's more than a coincidence that Heath St service quietly resumed following the accident. I think that was ultimately the straw that broke the camel's back on using the Brigham Circle switch.
 
Re: Driven By Customer 'Service' Parte Dos

datadyne007 said:
Also remember the accident. I think it's more than a coincidence that Heath St service quietly resumed following the accident. I think that was ultimately the straw that broke the camel's back on using the Brigham Circle switch.
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Oh, yes...and that's the risk of putting lightly-used manual switches into revenue service on a full schedule. They're not overbuilt for reliability like the automatic switches are, and are subject to human error. If the switch isn't open or closed 100% because it's gunked up with sand or ice or road flotsam, the train can split the switch and derail crossing over. The operator can forget to reset it (understand there's traffic zooming close by and/or kicking up water and debris at them during this maneuver) and cause the next train to derail. The wrench is heavy and the switches sometimes hard to turn, so less-than-strong operators can sometimes have difficulty turning them all the way (hey, it's not a crime to be out-of-shape/overweight or a female of diminutive build and drive a trolley). Etc., etc. They have these issues all the time with the ancient non-revenue Chestnut Hill Ave. switches during the daily Reservoir/BC equipment swaps. It's a major source of B service disruptions when they have a whoopsie during a shift change. I doubt the Brigham switches are the most immaculately maintained pieces of hardware on the Green Line. If they were meant to be used in anything other than an emergency or unusual conditions...they would've spent the bucks by now to install an auto switch controllable from onboard the trolley.


Until they do that, it's a safe assumption that threatened Brigham cutbacks are little more than a short-term bluff.
 
Re: Driven By Customer 'Service' Parte Dos

Are other short-turn switches such as Blandford Street and Packards Corner equally difficult to use?
 
Re: Driven By Customer 'Service' Parte Dos

Ron Newman said:
Are other short-turn switches such as Blandford Street and Packards Corner equally difficult to use?
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Blandford's switches are machine-controlled out of that little inspector hut. Cleveland Circle reverses are machine-controlled out of Reservoir. Heath loop they can choose the inner loop over the outer loop through old-timey streetcar and TT switching rules: power through the switch for one direction, coast through for the other (same way they used to choose Heath short-turns vs. Arborway thru service on the E and B vs. A at Packards). All D and Central Subway switches are tied to to the signal system and fully automated.

Pretty sure besides those listed all other B, C, and E crossovers are hand-throw because they're so seldom-used. Chestnut Hill Ave.'s are used daily, but the T is just too cheap to bother maintaining them (they yanked the eastbound-side switches on the B altogether rather than fix them after a split-switch derailment + downed wire torched the roof of a Type 8, so right now you can only go Reservoir-BC and back and can't divert anything to/from the hill). Whenever the B has to short-turn at Washington Sq., the C at Coolidge, or the E at Northeastern in emergencies they've usually got a T truck pulled over by the side of the road and a guy waiting with the wrench thingy.
 
Re: Driven By Customer 'Service' Parte Dos

I always thought the little hut at packards corner was to control the switches there.
 
Re: Driven By Customer 'Service' Parte Dos

davem said:
I always thought the little hut at packards corner was to control the switches there.
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Yep. Looks like the switch next to the hut is an automatic. But the other switch on that crossover (advance two tics east on Street View) is a hand-throw, so that's a really bizarre setup. Look at Washington St. instead: that's got the same hut but you can tell from the switch casing around the tracks that it controls machine switches for both sides of the crossover. No wonder they always short-turn at Washington or Blandford when the B is FUBAR'ed with a disablement and hardly ever attempt it at Babcock. Yuck...you'd need one guy in the hut and one guy 50 feet away with the wrench to work Babcock service in an emergency.

If I had to guess why they did it that way, it's that the hut probably had cable plant shared with the ex-A line Brighton Ave. switch. Back in the day they would've needed the hut more often to work the track split in revenue service if the coast/power-thru throw from onboard were malfunctioning and needed inspector assistance. You'll notice when Copley Jct. is malfunctioning they turn on bright floodlights at the junction and have a guy flip it from a power switch on the wall...so this Babcock hut could've been a similar backup system for the B/A split. And...in the switch's last days when it simply fed the residual Brighton Ave. pocket track...they may have disabled the trolley's ability to onboard-throw the switch and worked it exclusively from the hut when needed. Since that half of the crossover is right fricking next to the hut it's no biggie to wire up that half. But they probably left the other one hand-throw because Babcock turns were just that rare.

Confirming via Street View...Coolidge Corner and St. Mary's are definitely hand-throw. Northeastern (including the pocket track) is hand-throw. Heath inner vs. outer definitely automatic (small manhole cover in the pavement covering the switch machinery). Cleveland Circle looks like it's got the Heath-style power/coast-thru auto switches. Chestnut Hill Ave...hand-throw. Brigham does have a very new-looking hut that looks like it was taken straight from a Home Depot display...but the switches: still most definitely hand-throw.
 
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Re: Driven By Customer 'Service' Parte Dos

I've definitely seen people switching by hand at Cleveland Circle. I'm not sure if all the switches there are hand-throw, though, or if some of them are automated. (there seem to be a few different options on how to loop trains there)
 
Re: Driven By Customer 'Service' Parte Dos

So... it's currently rush hour on the Red Line... WTF is going on with these headways?!!

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Re: Driven By Customer 'Service' Parte Dos

Adam reports there was a disabled train at Kendall.
 
Re: Driven By Customer 'Service' Parte Dos

datadyne007 said:
So... it's currently rush hour on the Red Line... WTF is going on with these headways?!!
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You actually expected the trains to stop breaking down just because it's a new year?!
 
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