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Discussion relating to commuter rail, light rail, and subway operations of the MBTA.

Moderators: sery2831, CRail

 #1564732  by Trinnau
 
stevefol wrote: Mon Mar 01, 2021 2:32 pm I'm sure a solution could be engineered for the price electrification is going to need. But to some of the comments above about the weight of batteries, are folks here aware of the advances of Li-Ion in the last 10 years? The success of Tesla has led many railroads to look again at the battery concept, and in Germany in particular, dual mode Electric/EMU/battery is being seriously evaluated. It is depressing reading the old "FRA rules" stuff - rules that were designed over 70 years ago before silicon chips even existed, and are the thing that keeps so much passenger railroading third world in the US.
The FRA rules have more to do with crashworthiness especially in mixed use operation. Freight trains in North America are far larger than they are in Europe, so the standards in the US need to withstand higher potential impact thus need to be stronger. This results in more weight. As noted, the FRA has recently allowed for alternative concepts which allow some of the reduced weight.

My comment around weight and space is just that. An EMU without some kind of on-board power supply simply weighs less than "insert your carried mode of propulsion" - diesel/battery/hybrid/whatever. When comparing a battery locomotive to a diesel locomotive, battery technology just isn't there yet. It still has the weight and space drawback of a diesel engine. The only issue it solves is the noise/emissions, right now it is otherwise inferior in terms of actually delivering service regularly and will likely be for several years to come.
 #1564820  by stevefol
 
I'm fully aware of *why* the FRA rules are the way they are, but it is a 1950's view to talk about "if a freight train crashes into a passenger train". Technology exists to make that a near impossibility. There's plenty more damage likely moving at the speeds of a European HSR. And the rules made little difference at Chatsworth CA when 25 people were killed - a totally avoidable and unlikely accident had there been anything that passed for up to date technology on the system.

It would make more sense for the FRA to allow operations like the MBTA to be exempt from those "big freight train" rules in much of their area. Aside from Willows-Wachusset and LJ to Haverhill, where on the system are passenger trains sharing tracks with freight trains with more than a dozen cars during the day?
Decent Regional service in Europe utilizes EMU's running at 100mph. Let the end of the Fitchburg and Haverill lines run with stupidly overweight cars and lumbering diesels, or insist that CSX/Pan Am runs its freights after hours.
 #1564843  by eolesen
 
Technically, Amtrak is a 1950s view of how to run a train system. Should we get rid of that too?

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 #1564861  by Trinnau
 
stevefol wrote: Tue Mar 02, 2021 6:23 pm I'm fully aware of *why* the FRA rules are the way they are, but it is a 1950's view to talk about "if a freight train crashes into a passenger train". Technology exists to make that a near impossibility. There's plenty more damage likely moving at the speeds of a European HSR. And the rules made little difference at Chatsworth CA when 25 people were killed - a totally avoidable and unlikely accident had there been anything that passed for up to date technology on the system.
A near-impossibility is not the same as an impossibility. System failures, multiple human failures, freight derailments that foul the main track but don't trigger the signal system or PTC, the list goes on. It's going to be a long time before that technology is virtually bulletproof.
stevefol wrote: It would make more sense for the FRA to allow operations like the MBTA to be exempt from those "big freight train" rules in much of their area. Aside from Willows-Wachusset and LJ to Haverhill, where on the system are passenger trains sharing tracks with freight trains with more than a dozen cars during the day?
Decent Regional service in Europe utilizes EMU's running at 100mph. Let the end of the Fitchburg and Haverhill lines run with stupidly overweight cars and lumbering diesels, or insist that CSX/Pan Am runs its freights after hours.
Right outside North Station, Worcester-Framingham, Walpole-Readville, Walpole-Foxboro (when that service ran) and occasionally Readville-Route 128. Part of the problem is that it could happen at any time though - a train could outlaw for some reason and not get to where they need to be after hours. And with the freight railroads required to provide common carrier service there is nothing preventing an industry from popping up and suddenly running big trains during the day. The dirty dirt out of Everett is a great example, daytime freight on the Lowell Line for a time, and if CSX restores Framingham to Everett B721 service that'll probably return to it's traditional slot in the early afternoon out of Framingham.

MBTA can "insist" on after hours operation but the way the freight railroads retained their rights in the sale of the lines it'll fall on deaf ears if it impeded the freight operation too severely. If the MBTA squeezes the freight operation too much the carriers will cry to the STB about interference in interstate commerce. The reality is about half of the MBTA lines see larger than 12 car freight trains at some point in a typical 24hr period.

I'm not downplaying EMU service, MBTA has set the direction to make that the next step. I just don't see DMUs as a reasonable step at this point in time. Maybe 5-6 years ago before the overhauls and bi-level purchase, but the fleet is going to be set for 10-15 years without a need for new vehicles. That will give them time to actually get done what needs to get done to move forward with Rail Vision/Regional Rail - provided they don't shelve the plans again.
 #1564867  by BandA
 
Transportation is not risk-free; Why do we allow Prius and tractor-trailers together on dangerous, overcrowded highways? They should have automatic controls so that if automobiles try to tailgate a penalty-brake is applied.
 #1564896  by rethcir
 
I think you will see EMU's on the Providence Line within a decade, if that is successful and commuting does begin to return to 2019 levels you will see political will to get the rest of the system electrified. Also if electric cars do become a majority of new cars sold (I see this taking at least 15 more years in this country) you will see more mandate for electric CR and effective CR in general.
 #1564955  by BandA
 
Electric locomotives would make more sense on the Providence line, assuming a cooperative pooling relationship could be developed with Amtrak where Amtrak maintains the T's Providence Line locomotives and the T performs routine maintenance on the Downeaster.
 #1569800  by Gilbert B Norman
 
NRGeep wrote: Thu Feb 25, 2021 7:25 am Many moons ago and technology has evolved. That said, when the B&M, and NH etc incorporated RDC's into their freight heavy ROW's, what adjustments in signal and brake systems did they alter and if they did, is there anything that could be applied to DMU integration into modern railroads?
Mr. Geep, the New Haven only tried out RDC's once on the Shore Line; and let history show, that was very short lived. RDC's on the Springfield Line were an Amtrak-era "innovation".

Ordered up by Pat, those that were used on the Shore Line were a six car set, and was named the "Roger Williams'. They were in essence two RDC-1's with four RDC-9's separating them - even if the 1's had "noses". They were fitted with reclining seats and had some kind of galley to offer at seat food service. The New Haven dubbed such "Crusin' Susan".

But soon, along with the two Talgo trains which were withdrawn to the "used car lot" (for sale to any sucker), the six cars comprising "Roger" lived out a service life as Boston area commuter cars, through the Penn Central and, as noted, into the Amtrak era.
 #1569811  by kitchin
 
BandA wrote: Wed Mar 03, 2021 2:45 am Transportation is not risk-free; Why do we allow Prius and tractor-trailers together on dangerous, overcrowded highways? They should have automatic controls so that if automobiles try to tailgate a penalty-brake is applied.
The braking would charge up the battery on the Prius!
 #1569988  by TurningOfTheWheel
 
There's no realistic place for DMUs in the system at this point. The T has recently overhauled diesel equipment to last them another decade-plus, and EMUs are more likely on Providence and then Fairmount/any other lines that get electrified moving forward.
 #1570027  by Yellowspoon
 
For consists that vary in size, I would think DMUs are the way to go.

The WIkipedia article for RDC has, in part: "RDC trains were an early example of self-contained diesel multiple unit trains, an arrangement now in common use by railways all over the world. " if DMUs are common all over the world, why aren't they common here in North America?

Related: There is a YouTube clip entitled, "Ride the train Boston 1". I estimate taken March, 1987 (snow on the ground, Type 7's at Riverside, Elevated to Forest Hills). At minute 42, there are three Budd cars being pulled by a locomotive past Oak Grove. All I can assume is that the cars motors were beyond repair by this time.
Last edited by Yellowspoon on Fri Apr 30, 2021 8:21 am, edited 1 time in total.
 #1570033  by BandA
 
By 1987 the RDC's had been de-powered. The story is they took shields off of the engines & this caused them to be irreparably destroyed the following winter. At some point, Amtrak banned some of this equipment from running on the NEC, relegating it to the north side.
 #1570177  by Arborwayfan
 
First, why would the MBTA, which until Covid had trouble providing enough room for all its passengers on 5, 6, 7 car trains, with some bilevels, want to adopt a technology that was developed to make it cheaper to run one- and two-car trains on lightly-traveled lines? And own a small fleet of different equipment that would require more maintenance, more inspections, have more fuel-tanks to fill, etc.? Is there some advantage to DMUs for running long trains? Is there some place where the T should start running shorter trains? Maybe I've missed this earlier in this thread or some other thread.
BandA wrote:Why do we allow Prius and tractor-trailers together on dangerous, overcrowded highways? They should have automatic controls so that if automobiles try to tailgate a penalty-brake is applied.
I know you're being sarcastic and know the answer already, but for anyone new wandering in here some day :wink: :

Part of the answer is that people, in general, are more disturbed by accidents that kill many people at once than by accidents that kill one or two at a time, even if the bigger accidents are rare enough that the small accidents end up killing more people overall. There's public-opinion research about this, such as a study JR East did maybe twenty years ago in Japan. And we see it with PTC and which all the people acting as though the NEC was incredibly dangerous after the Philly crash, when it can't possibly have killed as many people per million passenger miles as I-95 and the other roads parallel to the NEC; same thing with the cab-cars-are-dangerous-so-lets-require-wyes-or-two-locomotives-and-make-CR-lines-so-expensive-that-everyone-drives-and-more-people-die reaction to that one highway-crossing wreck in California. I think we've also inherited a feeling that the big, bad railroad companies are killing passengers to make a profit from the days when they kind of did, in their Acme Easy Telescoping Pin-Coupled Wooden Cars. A lot of it probably doesn't make a lot of sense, I agree. If someone made models and ran calculations and came up with a finding that we could run European trains, saving $x million, so that we could run y times as many of them and carry z more passengers, and have a slightly higher death rate on the trains, but lure enough people out of their cars to avoid enough car deaths that the net result would be fewer deaths, I'd go nuts lobbying for it. But I think the general public wouldn't get it, and the people who ride the train all the time already would of course not want their rides to get even a tiny bit more dangerous.
 #1570411  by BandA
 
If the T had sufficient storage space it would make sense to have long sets and short sets made up & ready to use for different duty. As a government agency they should have access to ultra-low interest rates for borrowing (not sure if this is really true for Massachusetts) and virtually unlimited capital (taxes). DMUs could potentially allow operation of a train with just one person (Buses and some subway trains get along with one-person crews). DMUs potentially allow trains to split, half the train going to Plymouth and half going to Kingston, or part of the train going to Pittsfield and part going to Albany and a third part going to Greenfield.
 #1570455  by Arborwayfan
 
The splitting to serve different routes makes sense. I had forgotten about that. Of course, then you need to bring along an extra engineer, or pick one up at the station where you split.

Why are MUs more possible for one-person operation? Because the engineer is in the same car with some of the passengers, or something else? Also assuming something like high-level platforms and power doors?