• DMUs

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

Moderators: sery2831, CRail

  by R36 Combine Coach
 
Arborwayfan wrote: Mon May 03, 2021 9:41 pm 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?
Would ICC/FRA rules require two-man crews at minimum? SEPTA tried running the Newtown Branch in the early
80s with an RDC as non-FRA transit with one man (transit operator, not engineer) only with dismal results.

Lackawanna and later NJDOT split MUs at Summit, with one train to/from Dover and the other to/from
Gladstone, from a longer combined through train from Hoboken. PRSL did so with RDCs in South Jersey and
also Canadian carriers. Even Amtrak had a SPV on the the Springfield branch run though to Washington
on an Amfleet train (early 80s).

Even NJDOT's Arrow I MUs did so in their early years, running solo to South Amboy middays, and then coupled
together to form longer trains to accommodate the growing number of riders on the mainline for rush hours.
  by NRGeep
 
Gilbert B Norman wrote: Tue Apr 27, 2021 1:02 pm
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But soon, along with the two Talgo trains which were withdrawn to the "used car lot" (for sale to any sucker), the six cars comprising "Roger" lived out a service life as Boston area commuter cars, through the Penn Central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.
As a very young kid, I remember a single RDC running between Taunton and Norton Ma around '65 on the soon to be abandoned (former Old Colony RR) New Haven Stoughton branch. I don't believe I was hallucinating sir.
The Roger Williams is now property of the Hobo RR up near Lake Winnipesaukee these days.
  by Gilbert B Norman
 
Mr. Geep, the OCRR from Stoughton converged with the B&P at Canton. I will concede to you that a single RDC thence operated to South Station over the now-electrified Amtrak NEC.
  by NRGeep
 
Gilbert B Norman wrote: Tue May 04, 2021 7:59 am Mr. Geep, the OCRR from Stoughton converged with the B&P at Canton. I will concede to you that a single RDC thence operated to South Station over the now-electrified Amtrak NEC.
Correction: I was referring to the long gone Mansfield to New Bedford OCRR/NH line, not the Stoughton Branch. Taunton Locomotive Works tested their early steam engines on the line in the way back and there has been some discussion of reviving part of the ROW for Boston to New Bedford commuter rail, but will likely remain a bike trail partly due to cranberry bogs and other wetland issues which it abuts.
  by BandA
 
Arborwayfan wrote: Mon May 03, 2021 9:41 pmThe 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
Definitely more complex crew-scheduling
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?
Exactly, engineer in the passenger compartment just like in a rubber-wheel bus, power doors, level-boarding. And perhaps fare-readers in the doors that read the RFID chips as you board (and if you don't have a fare card they use facial recognition to find you later!).

If you have an 8-pack of double-decker coaches on the Boston-Providence or Worcester Lines, there's over 1000 passengers to spread the crew costs over. But if you only have 50 passengers on a train you are probably spending more to pay the engineer and don't have any money to pay for the fuel, depreciation, or maintenance. Of course those 1000 passengers will require parking lots at the stations where the 50 passengers can walk to their neighborhood stations.
  by Arborwayfan
 
BandA wrote:But if you only have 50 passengers on a train you are probably spending more to pay the engineer and don't have any money to pay for the fuel, depreciation, or maintenance.
How many actual or potential T commuter rail routes have 50 passengers on a train often enough to make it worth owning either a separate fleet for those lines and times, or making the whole fleet be that much more expensive to buy and maintain? (Honest question, not a snarky one.) Since you say the 50 could walk to their neighborhood stations, it seems like you might be picturing the Needham Line and the Fairmount Line in particular for the DMUs, but both of those have lots of people living near them; Needham used to fill four or five cars at rush hour. If there are just one or two roundtrips a day with very few passengers, it could still be cheaper overall to run those trips with long, empty trains than to have a special fleet just for them. I know Fairmount is planned for something like frequent DMU service in some long-range plans; might actually make more sense to convert it to subway?

Or are you thinking of something like having the next generation of control cars (cab cars?) be DMUs, so that in the middle of the day/on weekends those cars get cut off and run one-car trains alone, but the T doesn't have to buy or maintain an entire fleet of DMUs?
  by electricron
 
Battery ranges of new Stadler Flirts (BEMU)
https://railcolornews.com/2018/10/25/de ... ery-train/
"Designed for use on non-electrified or partly-electrified routes, the presented prototype reaches a current range of 80 km at a driving speed of up to 140 km/h in pure battery mode. 80 percent of the non-electrified routes in Germany can be operated with this vehicle. The three-part test carrier offers space for 310 passengers, including 154 seats. DE (Germany) has bought 55 trains with an option for 50 more.
https://railcolornews.com/2019/07/02/de ... -holstein/
FYI: 140 km/h is 87 mph, and 80 km is 49.7 miles.

Operationally, 50 miles on battery will completely drain the battery and would take an hour or more to fully recharge. At 25 miles on battery, you could return back to the originating station or overhead catenary without having to recharge the battery. For practically, limit that to a 20 mile range. At ranges further than 25 miles, but far less than 50 miles, lets say 30 miles, a quick 10-15 minute recharge at the terminating station should be enough charge to get the battery powered train back to an overhead power, either an overhead catenary or the originating station.

And Bombardier has battery powered Talents as well with a similar range.
What is the longest corridor MBTA runs commuter trains on, and are there any shorter than 20 miles away from a catenary or central station?

Another consideration why I suggest the practically of 20 miles vs 25 miles is that the batteries can use regenerative breaking to charge the battery, so you would never operations wise wish to charge the battery fully to 100%. Better to charge the battery than heat up resistor banks.
  by R36 Combine Coach
 
electricron wrote: Thu May 06, 2021 12:01 am What is the longest corridor MBTA runs on, and are there any shorter than 20 miles away from a catenary or central station?
The longest lines would be Fitchburg and Newburyport.

Arborwayfan wrote: Wed May 05, 2021 5:41 pm Or are you thinking of something like having the next generation of control cars (cab cars?) be DMUs, so that in the middle of the day/on weekends those cars get cut off and run one-car trains alone, but the T doesn't have to buy or maintain an entire fleet of DMUs?
It wouldn't be too hard to design/build a DMU to also serve as cab car, the HEP wiring and control would be
the most important. But most modern DMUs are multiple car sets (such as triplets), unlike the RDC or SPV. Metrolinx's UP Express has a "semi-permanent" configuration of "A" and "C" units. A units have full cab and
and nose end, though the C units have cabs and can lead, they lack power units and can only run when paired
with an A unit.
  by BandA
 
Is Wickford-BOS shorter than Wachusett-BON?
  by Trinnau
 
Wickford is about 65 miles but already has wire except for track 3 West of Providence.

Wachusett is 54
Worcester is 45
Newburyport and Middleboro are 36
Kingston/Plymouth and Rockport are 35
Haverhill is 33
Franklin is 30 (10 on the NEC)
Greenbush is 27
Lowell is 25
Stoughton is 19 (15 on the NEC)
Needham is 14 (5 on the NEC)
Fairmount is 10
  by The EGE
 
Wickford: 62.9 miles
Wachusett: 53.7 miles
Worcester: 44.2 miles
Newburyport: 36.2 miles
Middleborough/Lakeville: 35.6 miles
Plymouth: 35.6 miles
Rockport: 35.3 miles
Kingston: 35.1 miles
Haverhill: 32.9 miles
Forge Park/495: 30.3 miles
Greenbush: 27.6 miles
Foxboro: 22.7 miles
Stoughton: 18.9 miles
Needham Heights: 13.7 miles
Readville: 9.5 miles

Under SCR Phase 1 (2023), Fall River will be 56.6 miles, and New Bedford 60.0 miles. Proposed service to Buzzards Bay would be 54.7 miles.
  by Tallguy
 
The problem with DEMUs is the cost premium. The extra rolling stock cost negates the catenary savings.