Playing with a possible future train design for NYC (R324)

[engineerboy6561]

This is something I've been working on for a bit, inspired by some conversations I've been having on Discord, and also somewhat by @ABCDEFGJLMNQRSSSWZ's comments about having a somewhat more comfortable train with more seats and fewer doors for longer routes that don't quite see the same passenger volumes as the and do and so don't need the sheer volume of standing space the R211s have. The basic design is similar to an extended BMT Triplex, with 40' intermediate cars in the set and 45' end cars, as well as Jacobs bogies and open gangways within the set. Each car seats 32 with two dedicated wheelchair spaces, and has two double-leaf sliding plug doors per side similar to most modern trains in the UK and the Berlin subway. The idea would be for the BMT Eastern Division to run 12-segment trains (490' end to end), for the Franklin shuttle to run four-segment trains (170' end to end) and for the rest of the B Division to run 15-segment trains (610' end to end); I'd estimate capacity to be around 120-150 per car (32 seated, 88ish standing under normal loading, 118 standing under crush load with no wheelchairs), so full trains would have a capacity of 1800-2250.

The short length of the car segments serves two purposes; it allows the cars to comfortably navigate tight curves like Crescent St with minimal misalignment at car ends or overhangs, and it allows for lower axle loads (a 15-segment train would have sixteen bogies, so the same number as an 8-car 75' train). I was able to pull images of an NYC transit console from the R211 contract, and basically just used that here. Other fun features I'm playing with on this design are aluminum construction with crumple zones instead of stainless steel, and a novel bogie design that takes advantage of the ridiculously high power and light weight of modern permanent magnet motors to allow individual wheels to be powered independently; I found a really cool paper here that talks about using active steering on a bogie with independently powered wheels, and pulled together a rough draft of an actuator system designed to allow steerable axles (no more screaming wheelsets on tight curves) that I added to a bogie with individually driven wheels. I'm still fleshing out the details, but I'd love comments and thoughts, especially from folks like @RTOMan and @Kamen Rider who work with NYC subway trains here on a daily basis

Here's a look at the front of the set head-on (I'm still working on the design, hence the lack of destination signs, headlights, etc):

Here's a look at the side of the end car:

And the intermediate car:

Here's the operator's console with combined brake/throttle lever on the right:

And a look from above to show the seating layout of a car more clearly; the empty areas with the yellow/orange boundary are the wheelchair areas, and I shamelessly stole the seat design from the Class 345 trains on the Elizabeth Line in the UK.

.

Finally, here's a closeup of the bogie showing the spherical bearing and slide mechanism for the pivoting axle:

And another closeup showing the permanent magnet motors on the axle, as well as the central bogie member:

 

 

Edited March 20, 2023 by engineerboy6561

[Kamen Rider]

Right of the bat, plug doors are a no-no.

the reason we use pocket doors is they are easier to lock out in a failsafe manner.

on every current car, each door panel has a cut out switch, which when fully turned, drops a physical bar directly behind the door panel, locking it in place, along with de-energizing the door motor.

 

Can a plug door offer that level of safety? 

[engineerboy6561]

7 hours ago, Kamen Rider said:

Right of the bat, plug doors are a no-no.

the reason we use pocket doors is they are easier to lock out in a failsafe manner.

on every current car, each door panel has a cut out switch, which when fully turned, drops a physical bar directly behind the door panel, locking it in place, along with de-energizing the door motor.

 

Can a plug door offer that level of safety? 

Actually, you should be able to give a plug door that level of safety; this is what the actual mechanism looks like:

/

It shouldn't be that hard to take the same key y'all use for cutouts now, and cause it to drop a shaped piece of steel into the 90 degree curved in the door track via a linkage (which would then make it basically impossible to force the door open), as well as cutting out the door motor. That piece of steel would essentially jam the track and make it impossible for the door to open (and the door motor could easily be specified strong enough to open the door normally, but too weak to do anything to the shaped piece of steel).

Edited March 20, 2023 by engineerboy6561

[ABCDEFGJLMNQRSSSWZ]

Wow is this autodesk!? Good job.

I agree with Kamen rider that the plug doors aren't necessary if they would just cause more issues with breaking down and safety, especially since you'll have a fairly long streak of windows in the center of the car anyways, though I'm not an expert.

One thing I think could be problematic is the "dividers" next to the doors seem like they come out pretty far; at busy stations I could see those being quite annoying to deal with for passengers trying to get on and off the train. Also might be hard for wheelchairs to navigate.

40/45 foot cars is an interesting I've never really considered, but it might allow for more flexibility and and I think generally helps to maintain a more comfortable environment.

Gives me vibes of a shorter DC metro car (which I generally like), though the excessive transverse seating on DC metro isn't really as needed in NYC given DC metro lines can extend pretty far into the suburbs and in many ways act like a commuter rail for a lot of riders. In NYC, I'd estimate the vast majority of subway trips are less than 45 minutes.

The lines that could use this the most IMO are the trains that go to Coney like . All of those lines tend to be pretty slow getting into the city from Coney Island but aren't typically that crowded. Eastern Division  also makes sense, though the  is too high ridership and most  ridership is concentrated closer to Manhattan anyways.

[engineerboy6561]

1 hour ago, ABCDEFGJLMNQRSSSWZ said:

Wow is this autodesk!? Good job.

I agree with Kamen rider that the plug doors aren't necessary if they would just cause more issues with breaking down and safety, especially since you'll have a fairly long streak of windows in the center of the car anyways, though I'm not an expert.

One thing I think could be problematic is the "dividers" next to the doors seem like they come out pretty far; at busy stations I could see those being quite annoying to deal with for passengers trying to get on and off the train. Also might be hard for wheelchairs to navigate.

Thanks! This is Solidworks I'm curious to hear what @Kamen Rider thinks of the plug door solution I outlined a post or so back (use a piece of steel on a linkage to jam the track when the door gets locked out); they're fairly standard on most newer non-American subway cars, and they make the excess windows possible. Plug doors mean you no longer need a pocket to stash the doors in, which is the thing driving the ever-shrinking windows in NYC subway cars as the doors widen; you can have windows anyway that are modified to make room for the door pocket, which is what the London Underground does, if you need to keep the current door design.

Good catch on the dividers; they're like 30-36" wide and I could probably reduce that to 21-24" to make them useful but not intrusive.

1 hour ago, ABCDEFGJLMNQRSSSWZ said:

40/45 foot cars is an interesting I've never really considered, but it might allow for more flexibility and and I think generally helps to maintain a more comfortable environment.

Gives me vibes of a shorter DC metro car (which I generally like), though the excessive transverse seating on DC metro isn't really as needed in NYC given DC metro lines can extend pretty far into the suburbs and in many ways act like a commuter rail for a lot of riders. In NYC, I'd estimate the vast majority of subway trips are less than 45 minutes.

The lines that could use this the most IMO are the trains that go to Coney like . All of those lines tend to be pretty slow getting into the city from Coney Island but aren't typically that crowded. Eastern Division  also makes sense, though the  is too high ridership and most  ridership is concentrated closer to Manhattan anyways.

Yeah; the idea was basically like "what if we took a Class 345/777 and modified it for runs on moderately well used longer express services" and then the 40-45' car length fell out of looking at how I was going to keep everything aligned well enough for open gangways to work on tight curves while still having an overall train length that would use all the space on BMT platforms in both divisions but not be long enough to overhang signal blocks or platforms.

Edited March 21, 2023 by engineerboy6561