• A standard streetcar width?

  • General discussion of passenger rail systems not otherwise covered in the specific forums in this category, including high speed rail.
General discussion of passenger rail systems not otherwise covered in the specific forums in this category, including high speed rail.

Moderators: mtuandrew, gprimr1

  by Myrtone
 
This thread is about systems in continental US states, including Alaska as well as the contiguous state and also Canada's continental provinces and territories and possibly Mexico's continental states.

Could operators in North America agree on a standard streetcar width? In that case, platform buffers would be fitted to the doors of anything narrower.
This could allow quite large joint venture orders, which makes it easier to meet Buy America requirements. Large orders in North America could help justify the economics of buying North American and even allow superior rolling stock to meet these requirements. Large orders also lower the cost of customization of rolling stock.
It would also allow North American operators to piggyback on each others orders and also allow cascade arrangements. That is, for example, where new vehicles roll out onto one system and that system's other vehicles are moved to a different system, new or existing.

Of course, this standard width needs to be sufficient to allow for 2+2 seating, especially as this is also typical of buses. In case of low floor vehicles, greater width allows longer entrance ramps and maybe a higher interior floor. Most low floor light rail vehicles have motors and disc brakes outside the wheel track, requiring the trucks to be wider than the tracks on which they run, so plenty of clearance is needed for those trucks. Here for example is the truck of a Toronto Flexity.
It has longitudinal motors and a right angle drive. This leaves room for disc brakes but requires steps beside the aisle over them as pictured.
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This really negates the steplessness of the aisle of a low floor light rail vehicle, raising the question of why not have only 70% low floor. However, there are low floor models, such as the Variotram, that instead have direct drive hub motors.
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These do not require steps beside the aisle, even if the trucks are to rotate in curves, itself desirable on systems where the minimum curve radius (depots included) is less than 82 feet, besides, direct drive is also quieter.
However, direct drive requires more clearance to leave room for disc brakes, otherwise the hydraulic brakes must be applied to the steel tyre of the wheels as with Skoda's 15T.
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So could North American operators agree on a standard width with sufficient clearance for both direct drive motors and disc brakes outside the wheel track?

An example of a cascading arrangement would be for Portland and others with part high floor streetcars (not heavier kinds of light rail vehicle) to buy pivoting truck models than can be considered 100% low floor and their part high floor types being moved to different systems.
Or Cincinnati, Kansas City and others with 95-100% low floor fixed truck rolling stock could buy pivoting truck models, their fixed truck rolling stock being moved to different cities.
Last edited by Myrtone on Sat Feb 10, 2024 6:09 am, edited 1 time in total.
  by R36 Combine Coach
 
The closest to a standard streetcar was the Boeing in the 1970s.

Recall that Philadelphia is broad gauge and legacy systems such as the MBTA Green Line and SEPTA Market Street
Line have loading gauge restrictions. The retired TTC CLRVs and 1981 Kawasakis are reportedly very similar in dimensions.
  by Myrtone
 
I know about the Boeing LRV and I know it was extremely unreliable. But I am asking about a standard width, not a standard model. The idea is to specify a minimum clearance between level boarding platforms and the track centers, regardless of vehicle width.
  by electricron
 
Myrtone wrote: Fri Feb 09, 2024 10:36 pm I know about the Boeing LRV and I know it was extremely unreliable. But I am asking about a standard width, not a standard model. The idea is to specify a minimum clearance between level boarding platforms and the track centers, regardless of vehicle width.
It seems most streetcars in the USA do not have a standard width per say. If not bespoke for each transit agency, by each manufacturer.
  by Myrtone
 
They might not but could operators in Canada's continental provinces and territories as well as continental US states agree on a standard minimum platform clearance, regardless of vehicle width? This should be sufficient to allow quite a generous width.
  by electricron
 
Myrtone wrote: Sat Feb 10, 2024 12:21 am They might not but could operators in Canada's continental provinces and territories as well as continental US states agree on a standard minimum platform clearance, regardless of vehicle width? This should be sufficient to allow quite a generous width.
What platform? Not all streetcars use platforms at their stops.
  by Myrtone
 
What do you mean "what platform"? All new passenger rail vehicles (including streetcars) need to dwell at platform stops or stations, right? Surely all low floor ones do use platform stops.
  by RandallW
 
Unless any existing systems made a point of using the dimensional standards in common with another system, no two systems can't agree on a standard set of dimensions that won't require that one or both systems rebuild all their platforms and maybe other infrastructure to fit that dimensional standard. Just to pull an example from Toronto, the TTC will be operating vehicles from the same design that are incompatible because some Toronto routes use a gauge 2 inches wider than the other (incidentally the reason for this is that every system in Ottawa other than the historic Toronto system does use the same gauge and will be using other standards in common). A similar example from Portland is that the Portland MAX equipment can't be used on the Portland Streetcar lines because the MAX equipment is too heavy.

So the cost reality is that, yes, new transit systems should always follow a common standard with some other large system (i.e., they should follow the standards used by the San Diego or Los Angeles systems (to pick on the two largest by ridership per Wikipedia)) and that may eventually allow for some reduced costs in equipment acquisition, but I don't think that existing systems will be able to benefit unless some likely more substantial cost to modify the system is also paid (arguably with a negligible or negative return on that investment).

This problem also exists in "heavy rail" transit, with the extreme example that the three MBTA subway lines have, for historical reasons, mutually incompatible physical and other standards.
  by Myrtone
 
RandallW wrote: Sat Feb 10, 2024 10:02 am Unless any existing systems made a point of using the dimensional standards in common with another system, no two systems can't agree on a standard set of dimensions that won't require that one or both systems rebuild all their platforms and maybe other infrastructure to fit that dimensional standard. Just to pull an example from Toronto, the TTC will be operating vehicles from the same design that are incompatible because some Toronto routes use a gauge 2 inches wider than the other (incidentally the reason for this is that every system in Ottawa other than the historic Toronto system does use the same gauge and will be using other standards in common). A similar example from Portland is that the Portland MAX equipment can't be used on the Portland Streetcar lines because the MAX equipment is too heavy.
The thing with dimensional standards, unlike with track gauge, is that there is the option of building to those dimensional standards or larger. There is also the possibility of enlarging those dimensions a little at a time, say section by section or even line by line. Note the mention of platform buffers for anything narrower than that standard width. This is to avoid a wider gap between the platform and the floor when vehicles narrower than the maximum width are used and allows that standard width to be quite generous, which is especially important if the trucks of the vehicles need to be considerably wider than the axle length.
The Toronto Transit Commission does not have the luxury of converting to standard gauge a little at a time, this would instead require shutting down pretty much the whole network for an extended period of time, dual gauge track not being possible. So changing between those two gauges would be more costly with more disruption than enlarging dimension standards.
Could the Portland streetcars be used on MAX lines?
RandallW wrote: Sat Feb 10, 2024 10:02 amSo the cost reality is that, yes, new transit systems should always follow a common standard with some other large system (i.e., they should follow the standards used by the San Diego or Los Angeles systems (to pick on the two largest by ridership per Wikipedia)) and that may eventually allow for some reduced costs in equipment acquisition, but I don't think that existing systems will be able to benefit unless some likely more substantial cost to modify the system is also paid (arguably with a negligible or negative return on that investment).
Modifications that can be done a little at a time might well be quite cheap and simple, migrating from trolley-pole to pantograph being another example.
RandallW wrote: Sat Feb 10, 2024 10:02 amThis problem also exists in "heavy rail" transit, with the extreme example that the three MBTA subway lines have, for historical reasons, mutually incompatible physical and other standards.
I wonder if the problem is greater in heavy rail transit, particularly subway type systems where different lines are often quite separate from each other.
  by electricron
 
Myrtone wrote: Sat Feb 10, 2024 5:57 am What do you mean "what platform"? All new passenger rail vehicles (including streetcars) need to dwell at platform stops or stations, right? Surely all low floor ones do use platform stops.
Many older streetcar lines in the USA run in the middle of the streets nowhere close to the curve or sidewalk. Hence, no platform, just the pavement in the street. Not all existing streetcar systems are "new'.
By the way, you are the first to imply we are only discussing "new" lines.
  by Myrtone
 
First of all, level boarding will need to be provided at all stops on every new line, let alone new systems,* where platforms are possible and do work. Secondly, stops on legacy systems are also going to need platforms by the time new vehicles use those stops. I have started a thread before about how it could be done in narrow streets.
Streetcars are not like buses which enter the curb to dwell and can kneel to meet the sidewalk, they take up the center of the road and as rail vehicles, are not suitable for kneeling.
Modifying streetcar suspension to drop would require a complete undercarriage redesign, as was done with the Austrian Ultra Low Floor cars running in Vienna.
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Additionally, a streetcar that kneels but still takes up the center of the road still needs a platform, namely one only a tad lower than one with a more conventional undercarriage design.

I know Toronto Flexities have on-board ramps for stops that still don't have platforms and there *are* high floor light rail vehicles with wheelchair lifts and wayside lifts exist on some systems like the one in San Francisco, but at least outside museums, quicker, easier and more dignified usually wins in non-heritage applications unless there is a specific requirement.

The thing about level boarding is that how wide vehicles can be at most is affected by platform clearance and vehicle width unless there are platform buffers at the doors. Or check out the doors of Zuerich's Cobra Streetcars.

Hence a standard for a minimum platform clearance and preferably one that allows quite a generous width. Does nine feet or wider sound good?

*The exceptions are museum services and heritage lines.
  by eolesen
 
With just one manufacturer left (Brookville), doesn't that leave a defacto standard width and supplier for cross-agency orders?....
  by Myrtone
 
Not if the client gets to choose the width and aren't most operators buying from European suppliers?

If vehicles nine feet wide can run on a given network, then so can vehicles narrower than that. However, if there are platform stops, the gap from the platform to the floor will be wider unless platform buffers are provided at the doors. So the idea is to have a standard platform clearance for at least most North American systems so that even narrow vehicles build for some operators could still be transferred to operators who also run wider vehicles. To sum up, here are the reasons for this standard:
  • It allows more and larger joint venture orders, lowering the cost of customization and justifying the economics of North American content
  • It allows one operator to hire rolling stock from another, demonstration runs are an example of this, but not the only one.
  • Operators might also sometimes want to replace perfectly workable rolling stock that is still too new for museum services and allowing them to transfer them to other operators allows this.
In an age of level boarding, a standard for platform clearance allows this. Increasing clearances to allow wider vehicles should not be nearly as costly or disruptive as converting the existing oddball gauge systems to standard gauge would be.
A standard based, say, on the widest streetcars historically, may well ensure that streetcars are never too wide for the platforms.

Lots of things are larger in Canada as well as the United States then they are in most or all of Europe. Both countries are larger (this does not mean more populous but refers to are of land), especially Canada. Houses, stores and cars are generally larger as are trains.
In particular, streets being generally wider than in much of Europe suggests that North American streetcar and light rail operators would likely prefer a more generous width than is typical of, in particular, legacy systems in Western Europe where streetcars are, for historic reasons, too narrow for 2+2 seating.
In a lot of cases, they also could not ride on trucks as wide as the Variotram one pictured above, wide enough for direct drive hub motors to leave room for disc brakes and primary suspension to be outside the wheel track.
This, in turn, encourages the use of longitudinal motors and right angle drives, which in turn requires the floor to be raised to each side of the aisle, even if the trucks are fixed.

When it comes to, say, six axle vehicles, direct drive motors powering all 12 wheels should be preferred over more powerful longitudinal motors powering just the outer trucks.

Up to a point, wider is better, better for the user experience and more clearance apparently allows for better trucks, especially if the motors are outside the wheel track.
Last edited by Myrtone on Mon Feb 12, 2024 1:12 am, edited 2 times in total.
  by RandallW
 
Alstom (Bombardier), CAF, and Siemens all build light rail vehicles and streetcars in the USA. Not sure where the idea that Brookville is the only builder came from. Siemens and Alstom have a couple of standard North America-only models.

According to Wikipedia, in terms of dimensional differences by customers of the PCC cars, width the most common dimension to change, with (if I counted correctly) 4 different widths of PCC car produced. That didn't stop almost every component but the body itself from being common, though, which is what kept costs manageable.
  by Myrtone
 
RandallW wrote: Sun Feb 11, 2024 9:14 pm Alstom (Bombardier), CAF, and Siemens all build light rail vehicles and streetcars in the USA. Not sure where the idea that Brookville is the only builder came from. Siemens and Alstom have a couple of standard North America-only models.
I think it is that Alstom, CAF Siemens and Stadler are all European owned manufacturers, based in Europe, making European designed rolling stock on both sides of the Atlantic.
RandallW wrote: Sun Feb 11, 2024 9:14 pmAccording to Wikipedia, in terms of dimensional differences by customers of the PCC cars, width the most common dimension to change, with (if I counted correctly) 4 different widths of PCC car produced. That didn't stop almost every component but the body itself from being common, though, which is what kept costs manageable.
And PCCs were at least nine feet wide at most. I also linked to a page which notes that Twin Cities Rapid Transit built streetcars more than nine feet wide.
Before level boarding in street transit, when streetcars were often boarded directly from street level, narrower vehicles could easily run on any line accessible to wider ones with no problem.
Now with low floor vehicles and level boarding at nearly all stops, narrower vehicles sharing stops or stations with wider ones need platform buffers at the doors to bridge the wider gap at the stops or stations. This is a direct result of the greater platform clearance demanded by wider vehicles.
This comment, of course, is also valid for high floor vehicles on systems and lines with high platforms.

So, what is needed is simply a standard platform clearance for a great deal of streetcar (and maybe light rail) systems across the continent so that no light rail vehicles, including streetcars, are too wide for any of the platforms. Does anyone here understand that and why?