Second Avenue Subway Discussion

[RailRunRob]

1 hour ago, bobtehpanda said:

If you want to throw out nonsense hypotheticals because it doesn't fit your narrative, go ahead.

You're over complicating things again ive spent a year of my life studying ridership modeling GIS TransCAD  Journey to work projections... the full gamut. I'm in the software game now but I still have college buddies and old friends in the field of planning most 10-15 years in now. All I'm saying is this isn't the way I know the process to go. I don't have travel demand information or forecasting present or future. There's Volume to capacity ratio modeling.. Leave load volume.. Rider matixs. Last mile transit coverage maps , population projections how could you make a final conclusion without any of these? I don't know if I would consider it nonsense hypotheticals it's a Bachelor of Science in Civil/Environmental Engineering. I'm just asking the questions and saying a study will prove would it right or wrong. For the record, your sharp the knowledge is there and I wouldn't be shocked if you have a background in some type of (urban) planning you're very calculated and precise. So I'm not questioning any of that. Overall you're on point I just feel you're missing a POV based on what I see from people in the field and the base knowledge I've learned. Nothing more nothing less. 

Edited February 4, 2018 by RailRunRob

[bobtehpanda]

7 hours ago, Caelestor said:

The FEIS didn't account for that, but personally I think the practical maximum capacity of a 2-track subway is 30 tph, since station dwells and recovery padding needs to be built into the schedule. Plans also had a 26 tph limitation at Hanover Square, but that could probably be easily rectified to 30 if SAS makes it down to Manhatta.

I think 26 is what you can do max at a terminal with tail tracks, since trains need to be fumigated like at Forest Hills.

[RR503]

2 hours ago, bobtehpanda said:

I think 26 is what you can do max at a terminal with tail tracks, since trains need to be fumigated like at Forest Hills.

Hanover Square will be direct turn — no fumigation necessary. I’m pretty sure the 26 number is the MTA just not trying. The most common reason that I’ve heard is that they’ve placed the crossover cavern too far north for whatever idiotic reason, but take that with a grain of salt — it could be something else. 

[Union Tpke]

PATHETIC

Weekends

5AM Sat to 5AM Mon Feb3–5 Feb10–12

69 St/2 Av entrance/exit closed due to escalator work

[Wallyhorse]

20 hours ago, officiallyliam said:

I like this plan, but think the and should be the other way around. The already connects with all those other lines at Times Square and Union Square, since the Broadway Line acts as a sort-of circumferential through Midtown. The should be the one to go across 125 to allow folks from the West Side of Upper Manhattan to reach the Lower East Side easier and faster, instead of the which will just loop people back to the West Side again.

Agreed.

The  to Gun Hill Road via a rebuilt 3rd Avenue Bronx line (with fewer stops than the old line as these stations would be 600' in length as opposed to the 250-300 foot length of the old stations) is how I would do it with the  running to 125 since the would also be the prime candidate southbound to continue to Brooklyn via a new Schermerhorn Street tunnel that come in at the existing Transit Museum (Court Street as it would return to being an active station with the Transit Museum moved elsewhere) and then come in on the as-present unused local track and platform at Hoyt-Schermerhorn (with the / opening on both sides there) and the becoming the Fulton Local to Euclid while the  tuns to Lefferts (with the extended to Lefferts late nights) and the goes to both Far Rockaway and Rockaway Park.  

[Around the Horn]

2 hours ago, Union Tpke said:

PATHETIC

Weekends

5AM Sat to 5AM Mon Feb3–5 Feb10–12

69 St/2 Av entrance/exit closed due to escalator work

I don't know about you but I'd rather they proactively replace components during one weekend before they break and they're out for weeks...

[RR503]

1 hour ago, Wallyhorse said:

Agreed.

The  to Gun Hill Road via a rebuilt 3rd Avenue Bronx line (with fewer stops than the old line as these stations would be 600' in length as opposed to the 250-300 foot length of the old stations) is how I would do it with the  running to 125 since the would also be the prime candidate southbound to continue to Brooklyn via a new Schermerhorn Street tunnel that come in at the existing Transit Museum (Court Street as it would return to being an active station with the Transit Museum moved elsewhere) and then come in on the as-present unused local track and platform at Hoyt-Schermerhorn (with the / opening on both sides there) and the becoming the Fulton Local to Euclid while the  tuns to Lefferts (with the extended to Lefferts late nights) and the goes to both Far Rockaway and Rockaway Park.  

Wholly agree. Question is, if they build a bypass/manage to squeeze more tph onto QB, where do you send those trains? 60ish tph down Fulton seems excess... Could you jury-rig the Nassau-Montague tunnels to go to Hanover instead?

17 minutes ago, Around the Horn said:

I don't know about you but I'd rather they proactively replace components during one weekend before they break and they're out for weeks...

I'd rather Cuomo not rush completion and actually get the job done properly. 

[RailRunRob]

1 hour ago, Wallyhorse said:

would also be the prime candidate southbound to continue to Brooklyn via a new Schermerhorn Street tunnel that come in at the existing Transit Museum (Court Street as it would return to being an active station with the Transit Museum moved elsewhere)

Was The Court street station (TM) intended to be extended into Manhattan? Schermerhorn continues for only a block past Court street. Then a tunnel  would cut right under homes wouldn't they have built a little deeper if that were the case?  Your not getting to much depth with about 4-500 feet of runway even with a 4% grade. Joralemon at least has a clear path down to the waterfront. The BMT would have had to have more depth to clear the Bi level IRT and the drop off per say of the Brooklyn Promenade. State Street would prob be a better choice you should I think I've mentioned this before you might be able to bypass the Court street station altogether. And tie in right outside the Transit Museum. I don't have the exact tunnel footage or depths but from eyeballing it and video footage it might be a possibility.  

Edited February 4, 2018 by RailRunRob

[officiallyliam]

2 hours ago, RR503 said:

Wholly agree. Question is, if they build a bypass/manage to squeeze more tph onto QB, where do you send those trains? 60ish tph down Fulton seems excess... Could you jury-rig the Nassau-Montague tunnels to go to Hanover instead?

This is why they should have preserved the 1970s plans for a bi-level terminal at Hanover Square: one level could have turned half the trains back up 2nd Avenue while the deeper level sent the other half under the river to Brooklyn.

1 hour ago, RailRunRob said:

Was The Court street station (TM) intended to be extended into Manhattan? Schermerhorn continues for only a block past Court street. Then a tunnel  would cut right under homes wouldn't they have built a little deeper if that were the case?  Your not getting to much depth with about 4-500 feet of runway even with a 4% grade. Joralemon at least has a clear path down to the waterfront. The BMT would have had to have more depth to clear the Bi level IRT and the drop off per say of the Brooklyn Promenade. State Street would prob be a better choice you should I think I've mentioned this before you might be able to bypass the Court street station altogether. And tie in right outside the Transit Museum. I don't have the exact tunnel footage or depths but from eyeballing it and video footage it might be a possibility.  

I was actually wondering the same myself: how a continuation of the Court Street stop would actually get to the river. The IND Second System did have plans to connect Court with SAS, but I wonder how they were planning to do that. Slicing through Brooklyn Heights and tearing down houses just isn't feasible, and I don't think Court is deep enough to simply TBM under Brooklyn Heights.

Edited February 4, 2018 by officiallyliam

[RailRunRob]

4 hours ago, officiallyliam said:

I was actually wondering the same myself: how a continuation of the Court Street stop would actually get to the river. The IND Second System did have plans to connect Court with SAS, but I wonder how they were planning to do that. Slicing through Brooklyn Heights and tearing down houses just isn't feasible, and I don't think Court is deep enough to simply TBM under Brooklyn Heights.

 

Yeah, your right I just saw the 1939 plans seem like the line curves north not sure how accurate these drawing are. The only way I could think of is a curve off on to State Street there about 2,000 Feet to the waterline at about 70-foot elevation at Court street. So if the trackbed is about 35 feet in depth at Court Street (TM) that's the 35 feet to the Waterline and another 90 feet or so below the water line itself. That's about a 125-foot drop to the lowest point. The IRT tubes   (5)  are at about a 3.1% grade so id use that as a measurement.  Might be possible if the line swung over to State Street around Boerum Place.

Edited February 4, 2018 by RailRunRob

[Lance]

Remember, back in the '20s and '30s, unless you had some serious clout, if your house was in the way of new construction, you were assed out. You just hoped you would be given adequate compensation to move elsewhere. If I had to wager a guess on how 2nd Avenue would've connected to Fulton St using the Court St station, I think the city might've extended Schermerhorn St to the edge of Brooklyn to give the tunnel a straight shot to the river and not run too close to the nearby Joralemon St tunnels.

[RailRunRob]

1 hour ago, Lance said:

Remember, back in the '20s and '30s, unless you had some serious clout, if your house was in the way of new construction, you were assed out. You just hoped you would be given adequate compensation to move elsewhere. If I had to wager a guess on how 2nd Avenue would've connected to Fulton St using the Court St station, I think the city might've extended Schermerhorn St to the edge of Brooklyn to give the tunnel a straight shot to the river and not run too close to the nearby Joralemon St tunnels.

Indeed eminent domain would definitely solve for X. I didn't really considerate that because I was under the impression that Brooklyn Heights as a whole was already affluent in the 1930-40's and isolated from the industrial waterfront in comes that clout. I could be mistaken tho... Oddly enough the "39 "plan has the new IND crossing north of the IRT and BMT somewhere around Pierrepont? 🤔  Not sure the Exact route for that? But extending Schermerhorn would've worked as well.

Edited February 5, 2018 by RailRunRob

[officiallyliam]

9 hours ago, RailRunRob said:

Indeed eminent domain would definitely solve for X. I didn't really considerate that because I was under the impression that Brooklyn Heights as a whole was already affluent in the 1930-40's and isolated from the industrial waterfront in comes that clout. I could be mistaken tho... Oddly enough the "39 "plan has the new IND crossing north of the IRT and BMT somewhere around Pierrepont? 🤔  Not sure the Exact route for that? But extending Schermerhorn would've worked as well.

Yeah, it does look like that; I've seen a map where someone drew the Court-SAS tunnel as running under Pierrepont. That, however, seems unnecessarily complicated: you'd have to cross over/under the various IRT and BMT tunnels at Borough Hall. Plus, it would highlight the somewhat awkward location of the Court-Schermerhorn stop: it's to close to warrant building another station at Borough Hall to connect with the , but Court is a bit far to build a passageway to BH, and you'd end up missing a transfer between the Eastern Parkway and Fulton lines that doesn't exist in Brooklyn.

Suffice to say this part of the Fulton line could have been better designed.

[RailRunRob]

27 minutes ago, officiallyliam said:

Yeah, it does look like that; I've seen a map where someone drew the Court-SAS tunnel as running under Pierrepont. That, however, seems unnecessarily complicated: you'd have to cross over/under the various IRT and BMT tunnels at Borough Hall. Plus, it would highlight the somewhat awkward location of the Court-Schermerhorn stop: it's to close to warrant building another station at Borough Hall to connect with the , but Court is a bit far to build a passageway to BH, and you'd end up missing a transfer between the Eastern Parkway and Fulton lines that doesn't exist in Brooklyn.

Suffice to say this part of the Fulton line could have been better designed.

For sure, I was thinking about a possible path this afternoon.. Way over complicated Joralemon is on a grade almost Immediately outside of the Borough Hall station and the BMT is already at depth. I'd be super difficult to curve the line north and get under the IRT around Henry street. At a 3.1% grade, the IRT would have already dropped another 30-35 feet in depth. So maybe you pass over and then start then start your descent about 1,500 feet from there get some depth?.  Yeah, Court street as it stands isn't the way into Manhattan for the  .

Edited February 6, 2018 by RailRunRob

[bobtehpanda]

1 hour ago, officiallyliam said:

Yeah, it does look like that; I've seen a map where someone drew the Court-SAS tunnel as running under Pierrepont. That, however, seems unnecessarily complicated: you'd have to cross over/under the various IRT and BMT tunnels at Borough Hall. Plus, it would highlight the somewhat awkward location of the Court-Schermerhorn stop: it's to close to warrant building another station at Borough Hall to connect with the , but Court is a bit far to build a passageway to BH, and you'd end up missing a transfer between the Eastern Parkway and Fulton lines that doesn't exist in Brooklyn.

Suffice to say this part of the Fulton line could have been better designed.

This is kind of what happens when you build a subway system around revenge on your former employer instead of what the people actually need.

There were a lot of mistakes made during the planning of the IND. 53 St and Cranberry St should've been four-tracked. Crosstown should've connected to Franklin. The hubs should've connected to Atlantic Terminal and Queensboro Plaza. So on and so forth.

[CenSin]

11 hours ago, bobtehpanda said:

This is kind of what happens when you build a subway system around revenge on your former employer instead of what the people actually need.

There were a lot of mistakes made during the planning of the IND. 53 St and Cranberry St should've been four-tracked. Crosstown should've connected to Franklin. The hubs should've connected to Atlantic Terminal and Queensboro Plaza. So on and so forth.

So many missed opportunities.

[officiallyliam]

17 hours ago, RailRunRob said:

For sure, I was thinking about a possible path this afternoon.. Way over complicated Joralemon is on a grade almost Immediately outside of the Borough Hall station and the BMT is already at depth. I'd be super difficult to curve the line north and get under the IRT around Henry street. At a 3.1% grade, the IRT would have already dropped another 30-35 feet in depth. So maybe you pass over and then start then start your descent about 1,500 feet from there get some depth?.  Yeah, Court street as it stands isn't the way into Manhattan for the  .

You're right, which is a shame - it's in the right location, SAS should definitely connect to Fulton local, and the tiles at Court Street even match the color of the . 

Ideally, we could find a way to connect the Manhattan-Brooklyn SAS tunnel to the Fulton local line between Court and Hoyt to help mitigate the Cranberry capacity crunch by allowing both the  and  to run express, simultaneously relieving pressure on the Clark and Joralemon tubes. I think this been mentioned above, but how feasible would it be to build the river tunnel under State or Atlantic, building an 11th Street Connection-style junction to the Schermerhorn subway somewhere in the vicinity of Boerum Place? The State/Atlantic tunnel could include a stop near the waterfront to serve the Brooklyn Bridge Park and Columbia Street area (though this might be too close to the water).

This also allows us to keep the Transit Museum intact, which I'm sure we all approve of.

[RailRunRob]

6 hours ago, officiallyliam said:

You're right, which is a shame - it's in the right location, SAS should definitely connect to Fulton local, and the tiles at Court Street even match the color of the . 

Ideally, we could find a way to connect the Manhattan-Brooklyn SAS tunnel to the Fulton local line between Court and Hoyt to help mitigate the Cranberry capacity crunch by allowing both the  and  to run express, simultaneously relieving pressure on the Clark and Joralemon tubes. I think this been mentioned above, but how feasible would it be to build the river tunnel under State or Atlantic, building an 11th Street Connection-style junction to the Schermerhorn subway somewhere in the vicinity of Boerum Place? The State/Atlantic tunnel could include a stop near the waterfront to serve the Brooklyn Bridge Park and Columbia Street area (though this might be too close to the water).

This also allows us to keep the Transit Museum intact, which I'm sure we all approve of.

I feel so yeah I was talking about it up thread. I also have the line diagram of this section of the Fulton on a old HD i'll take a look at the office ill share if I find it. But  I think you'd have to gut the tunnel a rebuild an at-grade junction right outside Court street. Think the  where it branches off from the old South Ferry trackage.  I know the trackage from Hoyt is at different grades leading up to the Transit Museum IIRC it levels off for a few hundered feet.  The images below are of a State street idea. The area's in red would prob have to be demolished and a few surrounding building underpinned but I feel it's possible. Remember I don't have any information on utilities, water sewage, geological so it's mostly eyeballing. I didn't pick Atlantic because of the old LIRR tunnel (Bob Diamond) That would also be ideal, not sure if that's under historical protection ect..?  As far as a station for the Waterfront may be possible if you get depth maybe like York street,  a ventilation shaft could double as a station entry? Would be nice for the area.

 

 

   

Edited February 7, 2018 by RailRunRob

[R68OnBroadway]

Demolishing the buildings in the area would essentially be a non-starter thanks to NIMBYism and the fact that one of the buildings is a Quaker sanctuary.  If possible, it might be easier just to have the route curve to the right and go under Livingston instead, and in that case since it will run under NYCTA's building, they might actually try to build it properly and quickly to minimize disruption. (That is if MTA admins actually go there for more than a few hours a week.)

[RailRunRob]

48 minutes ago, R68OnBroadway said:

Demolishing the buildings in the area would essentially be a non-starter thanks to NIMBYism and the fact that one of the buildings is a Quaker sanctuary.  If possible, it might be easier just to have the route curve to the right and go under Livingston instead, and in that case since it will run under NYCTA's building, they might actually try to build it properly and quickly to minimize disruption. (That is if MTA admins actually go there for more than a few hours a week.)

I thought about that as well. Two have C6 zoned buildings you have to cut at a sharp angle their hefty buildings alot of weight to support shoring up that close. Plus with Livingston there's no path to the waterfront and Joralemon runs diagonally a bit to get a clear path downhill away from the heights (Promenade) if your building straight your going to cross paths with the IRT tubes. You don't have to demolish anything totally. May be able to underpin the property on the lower left corner (red) you just need that diagonal path the Highrise on the upper right is the hard part I can't tell from the images looks like an R9 zoned highrise. Still, think I'd be way easier than Livington you'd need to give the IRT tubes some space and all the properties you'd have to pass under past Akin place. This is all close enough to MTA HQ that they'll an eye on it. Take a look at the Livington angle below.

 

Edited February 7, 2018 by RailRunRob

[LGA Link N Train]

https://www.villagevoice.com/2018/02/07/the-second-avenue-subway-is-already-screwed/

something I found last night on twitter. Well apparently, they're saying that the  screwed up the Second Avenue Subway, but there's a logical solution and for that. It lies no further than the 1970's plans. Anyone see where I'm going with this??

Quote

Quote

See that third center track that will allow Q trains to stay out of the way of through service once it begins on the Second Avenue line? That’s right, you don’t.

The Second Avenue Subway may not be finished in our lifetime, but even if it is, it will be stuck with reduced capacity. Thanks to a crucial decision made by the MTA back in the project’s first phase of construction, according to a newly published Regional Plan Association report, the new line will never carry as many passengers as it might have unless the MTA spends billions of dollars to fix a key problem.

The report, which concludes a two-year investigation into the MTA’s capital project overruns, notes that the MTA decided to reduce the number of tracks at the 72nd Street station, where the Q train arrives on the Second Avenue line, from three to two, while the number of platforms was reduced from two to one. This, the RPA says, will have a cascading effect on service, reducing the number of trains that can be run on the Second Avenue line and the Q once future phases of the project are complete.

The original plan for the station at 72nd Street and Second Avenue called for two “island” platforms with a track on either side and one down the middle. Once the T — the yet-to-be-launched portion of the SAS on Second Avenue south of 72nd — entered service, the center track would act as a terminus for Q trains, while T trains would use the side tracks. Passengers would have a cross-platform transfer between the Q and T in both directions, and each train would run on its own tracks with almost no overlap.

But all that changed when the MTA decided to scale back the 72nd Street station to two tracks and one platform, the way it is today. As a result, once the southern section of the Second Avenue Subway opens, the Q will likely have to run all the way up to the future terminus of the SAS at 125th Street, running an alternating schedule with the T, even though the lines will only share six stops.

The only other option would be for the Q to switch to the downtown track as it approached 72nd Street, wait in the station until it offloaded all passengers, and then go back the way it came. But in order to do that, all downtown T trains would have to be held up until the Q can get going again. Rich Barone, one of the authors of the RPA report, doesn’t see this as a real solution, because the Q would be “literally in the way” of normal T service.

The consequences of this decision will only be felt once the T begins service after phase three of the Second Avenue Subway project is done, which is likely decades down the road. But once (if?) that happens, Barone says the T will only be able to operate every six or seven minutes at peak hours, hardly the frequency expected from a showcase capital project. For comparison, the 4/5 currently has a maximum capacity of a train approximately every two and a half minutes, and subway lines in systems with modern signaling system can operate with a train every ninety seconds.

As Barone points out, reduced capacity thanks to subway lines sharing track is the problem with “our subway system in a nutshell.” For example, since the A is restricted at multiple points along its line where it shares tracks with the C and D, even during rush hour the line can only run every six to fifteen minutes with good service. The T will be restricted to similar headways.

Why did the MTA do this? The transit authority did not respond to a request for comment before publication. But according to Barone — who spoke to the MTA several times during the two years he researched the report — the authority claims it had to reduce the width of the station so it remained under the Second Avenue roadbed without spreading underneath adjacent buildings, which would have caused “geotechnical” concerns, as Barone puts it. He says the MTA was also worried about getting the necessary easements on those properties as well as community pushback to the increased construction, all problems that the report notescould have been eased by “greater city involvement” during the design phase.

The MTA originally denied to Barone that the scaled-back station would have any impact on service. But when Barone gave a detailed analysis of his findings and asked the MTA to essentially tell him why he was wrong, he says, the authority’s response “was more like a punt” than an explanation; it neither confirmed nor denied whether Barone’s assumptions were correct. He characterized the MTA’s non-answer as a “red flag.”

If Barone is correct, this means the four-phased project has already left lots of future capacity on the table, and there isn’t much anyone can do about it. There is no feasible way to expand the station now that construction is done, or to provide the third track necessary for Q trains to dwell without being in the T’s way.

Now the challenge will be to find a way to provide more frequent downtown service on the Second Avenue line for future New Yorkers. Barone offers the idea of swinging the 63rd Street line — which currently serves the F — southbound at Second Avenue, but because the F also shares lots of Queens track with the E, one of the most crowded lines in the system, it has no capacity to spare. Other potential solutions would require billions of dollars’ worth of construction, far more than it likely would have cost to find a way to complete the 72nd Street station as originally planned.

“The reality is, it’s done,” Barone concludes. “We can’t change it. We have to figure out how to work with it as it is.” Barely a year after it opened, the Second Avenue Subway is already just another subway problem to be solved.

 

[T to Dyre Avenue]

1 hour ago, LGA Link N train said:

https://www.villagevoice.com/2018/02/07/the-second-avenue-subway-is-already-screwed/

something I found last night on twitter. Well apparently, they're saying that the  screwed up the Second Avenue Subway, but there's a logical solution and for that. It lies no further than the 1970's plans. Anyone see where I'm going with this??

 

Quote

Now the challenge will be to find a way to provide more frequent downtown service on the Second Avenue line for future New Yorkers. Barone offers the idea of swinging the 63rd Street line — which currently serves the F — southbound at Second Avenue, but because the F also shares lots of Queens track with the E, one of the most crowded lines in the system, it has no capacity to spare. Other potential solutions would require billions of dollars’ worth of construction, far more than it likely would have cost to find a way to complete the 72nd Street station as originally planned.

This is essential if the SAS is to provide true relief from overcrowded  trains and overcrowded transfers from the  and  lines. Otherwise, we'll be left with a reverse-branched, deep-tunneled  line with only a few crappy transfers running far below capacity. At the very least, they need to provide a ( V ) service via the 63rd St tunnel once Phase 3 opens.

Edited February 8, 2018 by T to Dyre Avenue

[LGA Link N Train]

5 minutes ago, T to Dyre Avenue said:

This is essential if the SAS is to provide true relief from overcrowded  trains and overcrowded transfers from the  and  lines. Otherwise, we'll be left with a reverse-branched, deep-tunneled  line with only a few crappy transfers running far below capacity. At the very least, they need to provide a ( V ) service via the 63rd St tunnel once Phase 3 opens.

If this problem ever occurs, then you can send some trains via second Av. Build phases 3 and 4 like planned in the 1970's. That way, you can still connect SAS to the Manhattan Bridge or short turn trains at 14 ST. I'll elaborate later

[T to Dyre Avenue]

40 minutes ago, LGA Link N train said:

If this problem ever occurs, then you can send some trains via second Av. Build phases 3 and 4 like planned in the 1970's. That way, you can still connect SAS to the Manhattan Bridge or short turn trains at 14 ST. I'll elaborate later

The “problem” in this case is the MTA’s service plans. They are planning for a line that will be forced to run far below capacity in Midtown and Downtown. Unless they provide a second SAS service that turns off onto the 63rd St tunnel into Queens, that’s always going to be a problem. Convincing the MTA to reconsider the “Shallow Chrystie” option at Grand St to facilitate a connection to the Manhattan Bridge won’t do a single thing to fix the problem. Being able to turn trains at 14th is only useful if there is a service problem further down the line. Sending some  trains there is not a substitute for running a proper full time Queens-SAS service, because the  doesn’t come from Queens, so it would be of no use for Queens commuters who currently transfer to the Lex.

Edited February 8, 2018 by T to Dyre Avenue

[RR503]

Here's the issue: 63rd has capacity. Queens Boulevard, at least in its current form, does not.

Given that the  and  both are high density lines running razor thin merge margins at high frequencies, reducing their numbers to squeeze a SAS  in on the express tracks seems unwise. So, really any pre-bypass SAS service would have to run via the local tracks -- which have track capacity, but are restricted at their terminal -- Forest Hills. The  and  run a combined 20ish tph during peak hours, leaving about 10 more tph for a SAS service. However, to use that capacity, at least two of the  or  services would have to be extended to 179th, where terminal capacity exists to host their frequencies. That said, even there, fumigation processes would have to be changed to permit one train every two minutes to enter the layups, lest dwell congestion create Forest Hills further east. Combined with the  , and the 3 peak hour s, 179 would be fumigating and turning 48 trains per hour -- more than any other terminal save for maybe Stillwell. 

This service pattern poses issues beyond just fumigation at 179. While the  would be forced to run express, shortening its route, the  (and to a lesser extent the ) would be made longer, worsening their already abysmal reliability. What's more, given that the  merge at 36th street would not be frequency matched (3:2 ratio),  trains being held to let an  pass in front would not be an uncommon occurrence, delaying the 30tph wall of local service a  would require. 

In a nutshell, while not impossible without the addition of a bypass, adding SAS service to Queens Boulevard would be one hell of an operational puzzle...

Edited February 8, 2018 by RR503