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RR503

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Everything posted by RR503

  1. Yes, provided that there's staffing at the terminal to double-end trains. I would minimize the use of that one, though. 4th and 7th are super popular stops. You'd probably end up with 7.5tph to 18th Ave, to Church + maybe 4tph and then a mix of Smith-9th, Jay (long relay to Bergen lower) and 2nd Ave for the rest.
  2. Absolutely, and in the case of Culver they knew about everything but the ADA initiative well in advance. The issues with Culver shutdown, though, are more real than with those other two lines. You have terminal capacity and yard access problems. On the former issue, even if you did double end every train and eliminate train clearing, you'd still get the +25 seconds from DGTs, along with speed penalties from the 3-yellow move to the yard, the GT10s on the yard ramp, and the AKs in the yard itself. Especially since those issues get worse with longer trains, I dunno if you could do full service out of that terminal. As for yard access, unlike Dyre and Sea Beach where yards are either not on the line or are accessible via alternate routes, there's no way for s to access CI if lower Culver is shut. You could fill the express tracks north of Church with layups like they do for the cold weather plan, but that's not great for crews and may not provide adequate layup capacity. There's also the issue of you having to keep lower Culver open to at least 18th to get trains out of those tracks and onto the local, unless you wanna come south from 4th Ave. These issues are likely tractable--you could keep 18th Ave open as an overflow terminal and hope that takes enough of a load off of Church (if not, 2nd Ave), and you could just bite the bullet on layups--but they're issues nonetheless.
  3. Agree, though the grid up there isn't all that conducive to efficient shuttle replacement service. The treatment of the Astoria line has likewise been shameful -- switch replacement projects, station renewals, ADA Astoria Boulevard, track panel replacement and now CBTC happening essentially without GO coordination. Some of this, to be fair, was a consequence of opacity as to future initiatives, but that's a controllable flaw -- a major project on a line should trigger conversations about potential concurrent initiatives.
  4. The proximity of Sea Beach to its alternatives, the insane, access-driven duration of the station work, and the fact that travel patterns were being seriously disrupted anyway would suggest that a full shutdown may have been a net positive here. s via West End (or to Bay Ridge), shuttle buses, increased service, etc and just be done with it ASAP and all at once. Would have likely saved some serious $$$ too.
  5. You’ve gotta respect the lengths to which this city will go to avoid uncomplicatedly adopting international best practices. Like seriously folks, CBTC systems that support 40+tph provided halfway decent ops are available off the shelf these days. It’s not that hard. This country’s fascination with ~~~innovation~~~ can be quite loony at times, and the institutional effects of systematically ignoring what everyone is telling you to do are great. At any rate, isn’t reducing customized unicorn products one of the goals they identified in the capital plan? There’s a joke to be made here about “how many academics does it take to install a signal system” but it is alas out of my grasp.
  6. Interlocking is run by computers rather than by electromechanical relays.
  7. No, it was NYCT's first solid state interlocking. Cut in in 2004 or thereabouts. 'Twas a disaster -- the thing is a lemon, and its (poorly signed, questionably calibrated) sea of GTs easily lose 90 seconds against what existed previously. I'm thankful it's being replaced, though am a bit apprehensive we may get something even more wacky.
  8. Full report is out https://new.mta.info/sites/default/files/2019-09/MTA 2020-2024 Capital Program - Full Report.pdf#page=14 I would post highlights, but there's honestly nothing too earth shattering in here. They're replacing Bergen St interlocking, which is funny, and it seems we may get work train CBTC, but beyond that the stuff in here is either super unspecific or already in the public domain.
  9. Unsure. One of the great advantages of Westchester Sq is that the station isn't abutted by buildings on its north side. Not the case at Woodhaven, though I'm sure there's some way to phase things to swing a conversion. (build out a length of middle track around the station and have local trains bypass in one direction while their side is rebuilt??)
  10. See the quoted post -- this is a conceptual phasing to convert Westchester Square to an express stop so that local trains can turn there rather than at Parkchester. It could work at Rockaway Blvd, though I don't know why you'd want to do that, and it'd be impossible at 72 without *major* spending.
  11. This is giving me heartburn. Also reinforces my thesis that the future of American urbanism is on the West Coast. NYC is so stuck, and without really anyone who can unstick it meaningfully.
  12. Short turn trains do not address the fundamental limitations of an interlined upper SAS, whether you see those as the unreliability caused by the merge at 72, the negative capacity impact on Broadway service, or the fact that lower SAS would never be able to reach its full potential. If I had to give just one suggestion, it would be to rework SAS. I and others have proposed a whole number of schemes to do so. I'd be happy to rehash those if it'd be helpful. The "structure may not support it" argument feels like quite the deus ex machina in the context of a plan as extensive as this. We can build subways out into Queens, a 4-track SAS and a new East River tunnel, but hell is gonna freeze over if we make some ironwork mods to an elevated structure at one of the widest points in its ROW...? Methinks that this is possible, and indeed advisable. I'm making this up in between research tasks so don't shoot me if there's some super obvious flaw, but it would seem like you could do either of the following: Is this the best way to do it? Probably not. But I daresay this is a relatively tractable issue. Now, to the points about ridership. Co-Op City has high bus ridership in part because it has no subway service. Untold thousands board buses every morning to get to PBP, stops on Dyre, etc. The number of people riding buses in the area would decrease dramatically with the number of subway extensions you're attaching to the area, and given that Co-Op is relatively difficult to access from the surrounding street grid and that areas even just over the highway from Co-Op have good access to the , I would not expect it to become a bus transfer hub as is Flushing. This is all to say that running express service all the way up there is a bad idea. You've correctly identified why the works, but the doesn't have those characteristics. Serving some local stops before commencing the express segment is the move here, and will help keep car equipment requirements and operating costs down in the long run. You certainly _could_ do this, I just don't know whether the value equation works out. Spending precious dollars on 1:1 replacement of elevated infrastructure is very IND, and is not a luxury we have today. I think you're much better off with the incremental improvements we've discussed--they're unglamorous, but they're also cheap, and crucially do not involve building even more underriver tunnels. I do want you to do that, and I very much stand by that want. Routing to the local tracks of Fulton will serve to reduce the capacity of their Manhattan trunk segments through reverse branching and will just be an annoying source of delay. You really should reconsider this. Generally speaking, I think we all need to step back and reconsider the ways we're integrating SAS into our subway plans. The best ideas out there IMO are ones which combine segregation on the north end (ie no reverse branch at 72) with proper integration at south (SAS-Nassau, SAS-Manhattan Bridge, etc). I think that's the way to go. I detailed the CBTC-merge capacity issue in another thread, which I hope helps you understand why those 40tph capacity numbers are somewhat dependent on their not being too many merges. For these reasons, as well as those of reliability, I think deinterlining QB is the way to go here. local, express/ extension, you take your pick.
  13. Yes, it's 10. It'll actually be really interesting to see what happens. I haven't ever observed relays at 86, so am unsure of how exactly they run it. The constraint I see is the fact that the x-over just south of the station is only in the facing-point direction, which will likely limit them to a one-pocket op. You can turn 10tph on a single pocket, but that does require some basic discipline that is sometimes lacking at NYCT.
  14. I don't know. You'd basically be telling the computer that it's okay to overrun a stop arm in cases where you're facing a home red for lineup and not occupancy reasons. Unsure that'd fly with system safety, though I do know they made some change to Canarise CBTC interlocking logic that had something to do with speed...
  15. Let me illustrate my point using Canal St. A southbound entering there usually gets a short route into the station, but faces a red home signal at the leaving end of the platform. That red home does not indicate a conflict so much as it does a lack of an established route all the way through the interlocking; a train tripped by it would likely overshoot onto the local track without any issue. Aside from the weird approach locking time thing that happens north of the station, operators enter in these conditions as if everything were normal -- they may brake a bit more conservatively because they're facing a red, but they do not act as if they're entering a stub-end terminal. CBTC, however, would enforce that level of safety. If my understanding of NYCT CBTC architecture is correct, a stop arm is considered a fixed obstruction, and therefore becomes the endpoint for a safe braking curve which, in turn, forces trains to enter interlocking areas at restricted speed -- imagine the entering 8th Ave, or the entering Main.
  16. On interlocking CBTC islands, I don’t think that’d work well. CBTC’s most positive effects on line capacity are at crowded stations — you sometimes actually lose capacity around merges because CBTC treats stop arms like they’re bumping blocks. In any case, many of the merge fluidity benefits of CBTC are accrued through reduced runtime variability over the course of the route (=better OTP at merges), which is a benefit you’d lose here.
  17. They issued _another_ supplement?? Re: timers, what are the speeds from 7th to Jay? If my memory serves me, it’s 30 into 4th, and then 35 off the viaduct, becoming 30 between Carroll and Bergen, and then 25 into Bergen Lower — all 2 shots. Is this correct? Thanks much! I find it the height of irony that they chose to implement while doing nada about the issues are Church. Those 2 minute dwell times from terminal ops are fixable whether it be by actually fixing the clearing issues, or by just extending s to 18th middle and running the area like 206/BPB. The extension could likely be done within the amount of time allotted for layovers, anyway...
  18. Hell, even during the peak of the AM peak there's space going n/b into Queens. Measurements frm. Roosevelt: 8-8:30 11 trains 8:30-9 13 trains 9-9:30 13 trains 9:30-10 13 trains 10-10:30 11 trains
  19. I would love that too, but even w/in existing service patterns, there's space. trains arrive in Queens around 8:15 and 8:40. From 8:00 to 8:30, we run 11 out of a potential 15 trains, and from 8:30 to 9 we run 13/15. Whether the terminal ops/requisite merge holds would work out, IDK, but this is worth noting.
  20. From the above courtesy of @Union Tpke (also @Lance can we merge these two threads?)
  21. @Union Tpke I'm increasingly skeptical of the "no space for more service" claim. There is incremental capacity avail on QB, and if we take the Canarise estimate of 28tph capacity on 6th local to be true, there's space for 4 more s even with 10tph of .
  22. ...is out in presentation form. https://new.mta.info/sites/default/files/2019-09/20-24 Capital Plan Overview.pdf#page=4 The lines getting CBTC are Lex, 63, QB-West, Crosstown, Fulton, Astoria/60th St. I'm trying to find a source for start/end points right now. My thoughts are essentially that this is a massive amount of money. You obviously cannot glean all that much from a PowerPoint, but if SAS 2's new price tag of 6.9 billion is any guide, it seems the brakes on cost sorta came off here. I'm gonna wait to form opinions on the individual projects until we actually know what they are.
  23. I was just going off of the description of the crawling into Bergen lower. It's two shots all the way from Smith-9th to there, and I doubt operators are super confident with area speeds at this point what with B4 not being used all that frequently for diversions. Merges and holds could absolutely be part of the issue, though, too. That merge is only an issue if you go above the few tph that's avail in Queens.

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