Description: The MBTA seeks to Purchase Multiple High Floor Diesel Units (DMUs) Vehicles in support of the Fairmount Line Service Improvement Project in strict accordance with the MBTA Specifications.
Category: Revenue Vehicles (Bus Heavy Rail...)
Buyer: Aidan Flynn | 617-222-5893 | AFlynn (email)
Documents:
141-14 Public Notice
Arlington wrote:Proposals are due 12/30/2014 in response to this RFP now posted in the MBTA Business CenterDescription: The MBTA seeks to Purchase Multiple High Floor Diesel Units (DMUs) Vehicles in support of the Fairmount Line Service Improvement Project in strict accordance with the MBTA Specifications.
Category: Revenue Vehicles (Bus Heavy Rail...)
Buyer: Aidan Flynn | 617-222-5893 | AFlynn (email)
Documents:
141-14 Public Notice
ns3010 wrote:Arlington wrote:Proposals are due 12/30/2014 in response to this RFP now posted in the MBTA Business CenterDescription: The MBTA seeks to Purchase Multiple High Floor Diesel Units (DMUs) Vehicles in support of the Fairmount Line Service Improvement Project in strict accordance with the MBTA Specifications.
Category: Revenue Vehicles (Bus Heavy Rail...)
Buyer: Aidan Flynn | 617-222-5893 | AFlynn (email)
Documents:
141-14 Public Notice
Wow, there goes all my previous doubt on whether or not this would actually happen... Let's hope the specifications aren't anything too crazy, and they could just use the same Nippon-Sharyo DMUs that SMART and Metrolinx are getting (although I've heard that initial testing has shown some issues with the hydraulic transmissions)
ns3010 wrote:I don't disagree that the DMU's are wasteful and unnecessary, that's why I was hoping all along that this would never actually happen. I've said it before, and I'll say it again, but they could easily run three car (even two if they wanted to) PP sets, with no real safety risk. It is done every day by other major and smaller roads, such as NJT and M-N, with no issues at all.
I'd rather see them spend whatever absurd amount of money they're about to spend on this on new PP coaches instead. Like you said, the single levels aren't going to last forever, and most of the cars are at or approaching retirement age. Had they spent this money on new PPs instead, they could use some of the remaining Pullmans and Bombs to run the high-frequency Fairmount shuttles. While some of the aging F40 stretches and Geeps aren't in the best condition and can't handle the 7-8 car bilevel sets as well as the HSPs, they would still be fine handling 2-3-4 car Fairmount scoots.
Bramdeisroberts wrote:Exactly, and here's my hunch.
Everyone here is complaining that the T is pursuing DMU's while ignoring the push-pulls and the impending need for a proper replacement for the F40's/Geeps and the flats. What nobody here seems to want to talk about is the possibility that the DMU's ARE the replacement for the older push-pull hardware. Is it really that far outside the realm of possibility that the T could be looking to drastically downsize the push-pull fleet, saving it for high-density work (think HSP46's pulling all-bilevel sets) where needed, while replacing everything else with DMU-based service?
The precedent is there if you look at the other "premier" commuter rail systems, even in North America. Metronorth prioritizes MU service, using push-pulls where MU's don't make sense, and the same goes for the LIRR and NJT, where push-pull service is almost exclusively high-density bilevel based trains, with MU's operating on a "lower capacity, higher-frequency" basis. SEPTA is all MU-based and is able to pull the same ridership as the T over a smaller area served (and one with far less of a traffic nightmare than we currently have). Sure, the other systems use EMU's instead of DMU's, but for the T, DMU's offer a great chance at proving the MU-based service model here without having the insane up-front costs of electrification.
Who knows what the plan actually is, but this all is a pretty intriguing possibility to me, and I, for one, am all for the T sticking their necks out and having even an ounce of real vision rather than watching them continue to pull the "this is the way we have always done it and the way we've always done it is the way we always will" routine that they've been so stuck in for the last quarter-century.
Bramdeisroberts wrote:I realize that Worcester, Providence, Nashua, Bradford (or if we're talking 30-year pipe dreams, an eastern route reactivation to Portsmouth) will always generate the ridership to fill big bilevel consists.
That said, what's to stop the T from purchasing 2 or 3-car trainsets and running them as 6-car sets at increased frequencies during peak hours on the 2nd-tier lines like the Eastern Route, Fitchburg, or Franklin, then splitting them up for off-peak service. Take the Fitchburg line, where the 6-flat sets as ~50-minute headways are approaching sardine-can conditions during rush hour. You could keep running push-pulls at current frequencies and add cars/switch to bilevels, or you could switch to running 6-car DMU sets (2 3-car sets or 3 2-car sets) which would get you 75% of the capacity of a 6-flat consist, but run them at 150% of the frequency. That would land you a net gain on the lines that can handle the extra trains, so you'd be saving your push-pull sets for the lines with either the ridership to justify big push-pulls or where bottlenecks prevent higher frequencies. Hell, of you ordered Silverliner-style carbodies, the low platforms wouldn't be the end of the world either.
During off-peak, split the big DMU sets (this is a BIG if, though I feel like it's much less of a case of "nobody does it" than it is a case of "the T doesn't do it") and now you have extra hardware to keep frequencies up off-peak while keeping the really big push-pull sets out of service off-peak.
It's all hypothetical, and there are some big logistical hurdles to bridge, but none of it would require treading over anything approaching new ground for any of the world's top-flight regional and commuter systems, though given that this is the T we're talking about, even that might be a tall order...
The EGE wrote:It's worth noting as well that DMUs only have any advantage at all over push-pulls on closely packed stops. On the southside that's only Fairmount (maybe to 128 or Dedham or Dedham Corp Center) and Worcester (Needham should be rapid transit by the time DMUs are systemwide); all four northside lines inside 128 are good candidates if you throw in infills*. That's, at most, six route stretching no further than 128 park-and-rides.
Over average stop spacing longer than say two to four miles, loco-hauled is vastly more efficient per seat mile. One big powerplant versus many smaller ones. And you only have to maintain that powerplant.
*Weston/128, Clematis Brook, Alewife, Union Square on the Fitchburg; Montvale Ave (Woburn) and GLX transfer (probably Lowell Street) on the Lowell; Revere and South Salem on the Eastern Route
Bramdeisroberts wrote:Wouldn't a far simpler reason why DMU's haven't been implemented in the post-RDC world be because most of the top-tier commuter agencies with the ridership to justify the higher frequencies that DMU's allow all inherited ex-NYC/PRR electrification infrastructure, making EMU's the no-brainer option? That's certainly the case with the MNCR/LIRR/NJT/SEPTA, and the same goes for the Illinois/Northern Indiana lines.
What's left in North America that honestly has similar per-mile ridership #'s to the T? There's Caltrain, which can and does fill its all-bilevel sets to crush capacity to the point that they're now electrifying. There's AMT, which electrified. Then there's the diesel METRA lines and GO transit, which both are closer in terms of ridership to Caltrain than they are to the T and have much more pressing platform constraints that severely limit service frequency and force them to increase capacity instead of frequency to add service.
I think that the DMU in the US was a real victim of bad luck and unfortunate circumstances. The RDC was a great, if flawed product, and the SPV-2000 was a turkey at the worst possible time, where all the railroads that had the need for and could afford MU's were all under wires, and the roads that could have used them (like the T) simply didn't have the funding to take a gamble on a new product with any chance that it'd be a lemon.
Once Budd went belly-up, they took with them all of that experience building FRA-compliant DMU's and thanks to those regulations, it only made sense for the Bombardier/Adtranz/Alstom/Kawasakis of the world to do that R&D legwork if there was a big enough order to justify it. Since the commuter railroads with the money were all running under wires or over third rails, or in the GO Transit/Caltrain situation, there never was that big buyer that could snag one of the big manufacturers for a proper DMU build, and the smaller startup commuter railroads just didn't have the money/numbers to afford new push-pull equipment let alone clean-sheet DMU's from someone like BBD or Siemens.
Meanwhile the MBTA/CR is a bit of an odd duck because while there certainly has been a need for MU-like service frequency in places like Fairmount, Chelsea/Lynn, and Waltham, we never had electrified service there like they do in NYC, Philly, or DC. Electrification a la AMT or Caltrain is the obvious answer, but there's never been the political will to spend the money on increased frequency, much less on any new hardware or infrastructure to serve our fairly unique needs. And so, to me, it's no surprise that with all of that in mind, we have yet to see DMU's properly implemented anywhere, much less in our backyard.
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