RR503

On 3/29/2020 at 2:49 AM, bobtehpanda said:

WTC is a two track platform with no tail tracks. It currently struggles with the but that's partially because of the nasty Canal St merge. You'd have to get the out of the way to even get close to 18.

To put this in perspective, New South Ferry is also a two-track station with no tail tracks, and IIRC it was stated to have a capacity of 24TPH.

WTC  honestly...isn't that bad. It's a stub, but you could (esp. post-CBTC) probably get >>20tph out of it, if we use 8 Av  and SF as our reference points. 

The issue with interlining 36 St is twofold. The first problem is that it eliminates any incentive to stay on the express beyond Roosevelt --  riders can use the  and  riders can use the . The  worked largely by giving ridership beyond Roosevelt a one seat ride across the peak load points into the CBD (thus relieving the ) and picking up nontrivial LIC-6th Ave ridership that used to use the . Very, very few people through rode beyond Roosevelt when the express was an alt for their destination. 

Second problem is, of course, ops. I don't think I need to explain just how garbage 59 St is. Its peak throughput is about 43tph across two tracks. Imagine running it at 50-60tph. It's simply an operational non-starter. 

Something to be thankful for here is that the T/O got the train to 110. Tunnel fires are scary; tunnel fires in deep bored tunnels built to 1900s egress standards and with little fire protection could have been even more catastrophic. My heart goes out to the family of the deceased; he's a hero.

11 hours ago, Trainmaster5 said:

The local recycle function on NTT was a great idea in theory. Reopen one car vs a whole section. In my experience in the real world that one door panel being obstructed can cause a delay equaling the time wasted with SMEE cars. The sensitivity of the door panels had to be adjusted (lessened) because the smart school kids on the  line discovered that they could delay a train as long as they desired by sticking a foot in the door tracks from inside the train. It basically forced the conductor to revert back to old school operations. Quite a few of us realize that station dwell time is dependent on the ridership and not solely due to the equipment. I have seen dwell time decreases because the riders on the train took matters into their own hands and forced the platform people to remove their hands and/or feet away from the door tracks. The people I’m talking about now were adults along the Lexington Avenue corridor and not school kids playing around in the Bronx. Old school or NTT didn’t matter if the riders weren’t cooperative. Just my observation. Carry on. 

Gonna disagree that it's a great idea in theory -- it's a great one in practice as well. It was just designed obtusely, so that you have to LR the entire train vs a zone, which means you can't use it in normal door operation or outside of an autorecycle sequence bc just pressing the button may recycle a door you're not looking at. 

7 hours ago, Union Tpke said:

Do you have any idea why this genius idea was approved? I have never gotten why they would needlessly eliminate flexibility at Church.

When the signal contract went out for Culver, Church was never supposed to be a real terminal -- it was just a place to squirrel away  trains. When presented with the opportunity to save maintenance $$$ on 4 switches, then, the agency went for it....et voila. 

8 hours ago, Union Tpke said:

You would have to completely shut service to Jamaica Center and rebuild the tunnels since they are bored so I am not sure how feasible it would be to add new crossovers there.

I'm not either. But it's certainly something worth looking at IMO.

52 minutes ago, JeremiahC99 said:

While an 18th Avenue  train sounds like a good idea, shouldn’t a policy change regarding fumigations and terminal operations be considered before extending the  to 18th Avenue? I feel like a little goes a long way here.

Church certainly could use a little help on the policy side, but there are real infrastructure constraints there -- especially if NYCT ever lengthens Gs to >300'. The ramp down to the lower level is timed to 10mph, making the diverging move down to the layups S L O W. The ramps themselves are also quite short, so if you get downstairs and don't have a lineup into a relay, a long train will overhang onto the main. Once you're at the yard, things don't improve. Some aspiring engineer decided to mess with the switch config in the yard durin the resignalling, so instead of having this: 

We now have this:

Which reduces flexibility and forces the installation of annoyingly restrictive signalling. 

The relays themselves are also only 600' long and have AK signals on them, so if you're a long train you're gonna c r e e p in, reducing turning capacity. 

These problems, with the exceptions of the ramp and relay length are fixable, but would require a decent bit of investment. When the alternative is good for ops, good for the budget (because of the amount of time it takes to relay a train, doing the 8m + layover time trip to 18th would be approximately cost neutral but ridership-positive), and good politics....why not? 

The 4th Avenue corridor has 3 branches and 2 tracks in each direction. You're stuck with a merge kinda however you want to slice the pie, so to speak. The move off of West End is nasty, so I'd imagine that new xovers south of 36 could only be an improvement.

Free yard space! Also overflow for whatever you can't turn at 18. 

25 minutes ago, LaGuardia Link N Tra said:

I prefer to not use Crescent Street because to me, it seems like an odd place to short turn trains, especially when you have a station like Woodhaven Blvd, which is a good transfer point between Subway and Buses. Particularly the  and the Q52/53+. As for 111th, I’m not sure why I didn’t think of short turning trains there. And just to clarify, I moved the crossovers on BOTH the upper and lower levels of JC/Parsons, that would bump things to 15 TPH. 

If you move the crossovers, you could definitely do more than 15tph. Both levels have tail tracks (albeit ones that are normally occupied), so with good switch geometry I don't see any reason why we shouldn't be looking at capacity figures that begin with a 2 or a 3.

13 minutes ago, XcelsiorBoii4888 said:

Thank you. Your original response said CBTC can only fix 8th and Fulton, which is why I was confused.

Ah, sorry--CBTC can fix all of these areas, but they're only installing on 8th and Fulton. 

33 minutes ago, XcelsiorBoii4888 said:

If that's the case, you don't think CBTC would fix that? 

I know the original post was about currently improving existing operating speeds with a T/O, which makes sense as to why the timers are there now...but down the line, CBTC couldn't automatically fix that?

I'm a bus guy so my apologies if this was explained before. I study transportation engineering and I don't see why a longer stretch of track would benefit from slower speeds to maintain capacity. 

See my original response. CBTC fixes this 100% because your speed profile is the lower of maximum allowed speed for geometry and maximum safe speed for following. This, plus the acceleration benefits that come with CBTC ops are why you see such big runtime gains when you turn CBTC on.

27 minutes ago, Lex said:

CBTC can address operator variability, but it can't do anything about physics.

The whole point of my reply is these aren’t exactly physics (curve speeds etc) problems: they are choices made relative to a very specific set of constraints inherent to fixed block installations.

FWIW, CBTC fixes operator variability but not conductor variability, which can be punishing in high ridership segments. 

9 hours ago, XcelsiorBoii4888 said:

I don't get it though, there's other sections of track that are more wild that have higher speed limits. What exactly are those timers for? I would love to know. Has there ever been an accident on that are stretch of track? 

If I were a betting man, I would be willing to wager that a majority of timers exist for control line safety (ie making sure trains are going slow enough that, given a certain distance ahead of a signal which makes it red/maximum attainable speed, there's sufficient stopping distance) rather than to protect nutty track geometry. Most CPW timers are there for that reason, or were baked into the resignalling they did there in the late '80s because controlling train speeds actually can help _increase_ capacity (this is the primary motivation behind many timed areas on downgrades: it's not so much that we don't want trains doing 65 as it is we don't want to have the control line lengths that'd come with that). 

21 hours ago, LaGuardia Link N Tra said:

As for why I didn’t add the  to West End on my map, it’s mainly due to the fact (and I remember this from a previous discussion) that West End ridership is in a higher demand for Express Service as opposed to Sea Beach. I’m not sure if that argument alone can suffice not swapping the  and  or if ridership demographics changed since, but that’s my notion. Don’t know why but your  and  swap made me think of the Canal Flip for some reason...

Yes, West End loves express. But this gets you yard access for the  and doubles their frequency or allows express. I'd say that's a viable trade-off, no? 

22 hours ago, LaGuardia Link N Tra said:

As For not adding the  to 18th Extension. Even though I said “I didn’t feel like [adding] it”, I wasn’t trying to make any arguments there, I just simply did not want to add it into my map. I’ll admit that a  extension to 18th would be nice though, but at that point, why not run it to Kings Highway and Expand Culver Express Service? 

Because Stillwell can't handle that many s. Absent some rebuild plan, you need KH as a relief for s, which forces the  to 18 or Church. Of those two, I'd take 18th with the equivocation that at tph >10 you should split between the two terminals as you really don't want to be running a single pocket at those frequencies. 

22 hours ago, LaGuardia Link N Tra said:

The main reason for the short turn was to avoid congesting the Terminal at Jamaica Center. This also put me under the notion that the  between Broadway Junction and Jamaica Center would need a maximum of 12 TPH. I was also trying to go for some type of Terminal Operation similar to Parkchester on the . But since my map includes the upgrade of fixing that terminal (which the interlockings shouldn’t even be that far from the platforms anyways). I guess I could get rid of the Short Turn plan I had with  trains.

Ah, I see. That makes sense, though you could easily use Crescent or 111 St to short turn. Much less pretty of an operation, but doable enough. I see on your map that you moved the crossovers on the UL at Parsons -- why not do the LL too? 

7 minutes ago, XcelsiorBoii4888 said:

Until the  does consistent 45+ mph the CPW, 8th Ave and under Fulton St through the entire express run then I won't be happy. 

CBTC will take care of 8th and Fulton, but you can't really do anything about the timers on CPW. Whatever you may think of their implementation, they do indeed serve real safety functions!

1 hour ago, RestrictOnTheHanger said:

I think either @Trainmaster5 or another employee explained a while ago why trains are generally not cut in half anymore. I think it was due to added labor time and cost to do that. 

Currently the late night Euclid - Lefferts shuttle is the only half length operation. The weekend was too when it only ran to Myrtle or Essex in the past. 

I wonder if they truly would consider some form of shortened train lengths though in the current situation

They stopped turning 10s into 8s or 6s for that reason. Splitting a train in half isn't nearly as annoying an operation as doing some uneven cut, as you end up with some stump when you're done. Lefferts , Dyre , Myrtle  do this every night. Shortened trainsets would free up CRs and reduce ABDs related to CR availability, but you wouldn't save that much $$$. Remember, a work program is a work program -- whether you run what's in it or not, those called on a given day still have to show up. 

6 hours ago, LaGuardia Link N Tra said:

@RR503

I managed to make a De-interlined NYC Subway map (with a time table) that included many of the talking points that you addressed with your masp. However, there were a couple of factors that I chose not to change. 145th Street in my opinion is a Junction that would need to stay interlined unless some SAS connection to the CPW Local Tracks were made. I also did not swap the and south of 36th Street. While I agree with you on the fact that Yard Access would be important for the , swapping it wouldn't be a good idea in my opinion. As for the , I included a few infrastructure upgrades along that line for a personal project that I'm working on. I also didn't include your  to 18th Avenue just cause I didn't feel like it. What do you think?:

Map - https://drive.google.com/open?id=1H8_ABLoi9Ao9NT608MHifUUR-nbTw4uj&usp=sharing

Timetable - https://docs.google.com/spreadsheets/d/1LUmnHPDF-T7_Em5mr93U4qbN7zxqiGpXYM8Xhd01RhE/edit?usp=sharing

So I guess my question is why you chose not to do things like  to 18 and  to West End? Those things have clear operational (and ridership) upsides, which have been talked through in the past/in this current discussion. There certainly are counterarguments to be made, but "I didn't feel like it" isn't really one of them. 

Also am wondering what your reasoning with the  is. At 16tph, the schedules for  express allow a merge at Bway Jct without too much pain, and there's nonzero demand between Bway Jct and points east. Why short turn locals? 

5 hours ago, T to Dyre Avenue said:

Great maps. But for the second map, I was a bit surprised to see you have the  via Brighton and the  via 4th Avenue Express, as well as the  running local on CPW and the  express.

On the short term map,  express/ local allows you to deinterline 59, 50 and Canal without touching Queens and helps keep the  to a decent length. Once you've done that, you're somewhat forced to do  to Brighton --  to 4th would mean you either end up with 4 weekend services on CPW (the two expresses, and then two locals because you need one for each branch of 4th exp), more local than express service on CPW, or one of West End/Sea Beach without weekend service to Manhattan. On the long term, I figure a) continuity is good, b) the logic rel. the  still holds, c) the  as an overlay Brighton Express/Concourse Local service is legible and really pretty to operate (clear hierarchies of primary/secondary services makes disruption management easier because it's easy to thin out/suspend a train without messing up some branch's service). 

6 hours ago, Union Tpke said:

While we are on the subject of issues with NYCT CBTC, how do you think the problem with CBTC and interlockings could be remedied? Is this an issue with other systems? I doubt it considering that 36 TPH can be run on the Victoria Line, which has several trains short-turn.

Honestly I don’t know. It’s unclear whether this issue is a function of the way NYCT zone controllers/interlockings interact with CBTC, whether this is some AWS overlay bug or something else entirely (perhaps related to our conservative design assumptions?). 

It's sad how the transformation plan frames the choice between reform and the status quo one between a poorly thought out RIF and not doing that. The root of ~70% of the MTA's problems lie in process: fix those, and you'll realize huge efficiencies, and will be able to do RIF (which is needed) without affecting vital operations. This will be interesting to watch, both in the near term w/ Corona, and also thinking long run, because a ton of out-year budgets are predicated on these Transformation savings... 

5 minutes ago, P3F said:

What would be the maximum estimated capacity of the Broadway Line between City Hall and Cortlandt Street, with and without CBTC?

3 minutes ago, Union Tpke said:

Without CBTC 21 TPH. If done right, 30 TPH should be possible with CBTC.

What UT said. The only equivocation I'd make rel. CBTC and capacity is that current NYCT CBTC architecture locks trains out of stations until the train in front is fully clear of the platform. Doesn't make a huge difference on stations where the leader can exit quickly, but at Cordlandt and City Hall (especially City Hall, given entrance speeds there are also slow)  you'll need that ability to achieve full capacity. 

7 hours ago, Union Tpke said:

In about 2014 or so I was on an  that terminated at Canal Street.

Yeah, they had some turn there when Montague was out. 

2 hours ago, Union Tpke said:

I am not optimistic that assistance will come.

If it doesn't, we're likely going to have a front-line seat to a wave of transit authority defaults/bankruptcies. There really isn't a way for the agency to cut its way out of this -- the gap is too large. This isn't to say that I at all disagree with your assessment here, just saying this will be catastrophic. 

7 hours ago, Union Tpke said:

Even managing to terminate a few trains at Canal Street could help a bit. How many do you think could be terminated there without screwing up service?

Maybe a 3-4 per hour? But even then isn't good -- the second you start turning trains there, you're going to cause irregular gaps in through-running service unless you're efficient. Which they aren't. 

7 hours ago, Union Tpke said:

Agreed, but the map is aspirational. How many TPH do you think could terminate at City Hall LL?

There's aspirational and then there's ~aspirational~ though, and given that I'm not convinced of that project's relative merit...

A stub end terminal with meh crossover placement? With CBTC, idk, 18tph? Which is more than you'd ever need. 

7 hours ago, Union Tpke said:

Wouldn't it make more sense to have the shuttle track be in the middle so riders heading to 145th or 148th can get an easy cross-platform transfer from trains heading uptown?

Would be nice, but that means grade separating the junction. Don't think that's an easily justifiable investment. 

5 hours ago, R10 2952 said:

Regarding BMT City Hall's lower level, I've always wondered about it myself- didn't some BMT Broadway trains go in and out of service at Canal Street in the '90s? Used to see trains laid up on the center tracks between the two stations all the time back in 1999-2000. 

Up until spring 2018, there were s that entered service at Canal/Tunnel at 7:55 and 17:24. I don't _believe_ we schedule trains to lay up there outside supplements anymore (though don't quote me on that, I'm just skimming schedules and there may be deadheads from DIT), but it's certainly a known move for the agency. In years past, you're right that there were even more such trains -- in 1991, 4 s and some number of s entered service there for the AM rush. 

Looks like they had to ABD one  interval, and then just ran the rest as s.

3 hours ago, trainfan22 said:

I wonder why they don't run an Saturday schedule during the week to save money? Ridership has been really light ever since the City damn near shut down due to the virus.

It wouldn't save much money. All the weekday crews would still have to report, which would mean you wouldn't have to dole out O/T to cover missing crews' assignments, but that you'd still be paying the lion's share of your normal cost structure. Something to consider, but it really isn't perfect either. 

7 minutes ago, LaGuardia Link N Tra said:

Why not make an adjusted schedule or service pattern for the Corona Virus or something along those lines?

Writing schedules is an extremely complicated process. Your average supplement (what's used to run diversions) takes months to write and coordinate; the process for assembling the base schedule used in the pick starts something like 18 months out. Even if you did pull together a supplement, though, you'd probably not even end up saving all that much. The base work program is an optimized fabric that minimizes the number of crews required to run service (with some flaws, but this is generally true). As soon as you start picking at that -- even if you're running less service -- the number of crews required actually usually goes up because that fabric gets disrupted. This is why GOs that put the  on a 12 or shortline the  to 145 almost invariably require more resources than their base equivalent. 

14 minutes ago, Lex said:

But why bother doing it if the buses can fill the gap fairly easily? Either have through-run service or get rid of it entirely, but this will do no one any favors, especially since it fails to address any of the factors that keep the others around.

You need to preserve rail up there for yard access — you're going to need that put in capacity if you want to deinterline Nostrand without blowing your ops budget. If you’re going to have rail up there, you may as well have a shuttle. It’s not perfect by any standard, but it’s politically better than nothing, and should be relatively cheap to operate. 

14 minutes ago, Lex said:

Speaking of questionable investments, why bother building a northbound flyover for Dyre Avenue if the express service starts/ends in Wakefield? Last I checked, there are switches north of where the existing southbound flyover joins, and your (investment) plan calls for night service to/from Manhattan on both branches. (If it's actually a mistake, then I won't force the issue, but if it's not, then I'll need a good explanation.)

A mistake — cut the flyovers. As you can tell, this went through many iterations before I was happy with it; originally I had  express and  local, but decided that it’d likely be mighty difficult to justify such a significant investment when a zero cost alternative that had the same operational impact existed. I’m very open to arguments the other way, but that was my reasoning. 

Just now, Around the Horn said:

A quick question about the Lenox in the last map, how would you turn it around at 135th without getting in the way of the ?

You'd rebuild 135 -- move the s/b track to where the spur is, move the platform with it, and add a 3rd track alongside the western edge of the 135 sb plat for the shuttle. You'd have to build a bit of tunnel north to 142, but that should (?) be doable? 

2 hours ago, Union Tpke said:

@RR503 If you want to deinterline in the peak direction, you can also add a third track to the Williamsburg Bridge.

You could, but again, I'm aiming for investments that could concievably get done by the MTA in this day and age. I also am still somewhat unconvinced that this specific project should be a priority -- it'd be $$$ for a nontrivial operations gain, but only a small capacity gain. 

49 minutes ago, Around the Horn said:

Related since we're talking about Broadway capacity: how feasible is fitting out City Hall lower level as a short turn terminus?

I would imagine if it is feasible it would be orders of magnitude better than short turning at Canal Street and fumigating.

If you reconfigured it a bit (ie abandoned 4 tk and used M and 3 only) you could probably extend the western island. Then you'd just need to signal it properly... It's something I'd like to see looked at, though only if it's found that CBTC cannot fix the curve issue. 

3 minutes ago, Union Tpke said:

Are you going to change it to 30?

Maybe not 30, given that Concourse and CPW aren't _that_ high ridership, and that returns to additional trains really start to go down >20. 24, say?

And yes, I'll add those.