Greetings all.
I have not posted here before but as a regular contributor to SkyscraperCity, I have found the need for more expertise from rail-based transportation experts, such as many of you.
Specifically, I am inquiring about the potentials for streetcar vehicle (tram vehicle) or LRV capacity expansion.
We just opened a modern streetcar line here in Milwaukee called “the Hop”, to much excitement and popularity. The vehicles we are using are Brookville Liberty Modern LRVs, which I believe are about 67’ in length. The question has arisen, however, if and what kind of capacity expansion these vehicles could endure.
I understand the vehicles can be hitched together as is done in some cities, but with two operator compartments at each end, hitching these vehicles together seems like it would be a pretty awful waste of useable space just to gain the extra passenger capacity. Also, if the vehicles are hitched together, I would assume the existing platforms would be too short to accommodate fully double-length LRV.
The question, then, if any of you might know the answer, is are these Brookville Liberty Moderns able to have just their cabs extended or would that be a ridiculous proposition altogether? I assume that you can’t just easily open up and pop in an extended cab into a vehicle like this, and that the way you would do it is just to hitch the vehicles together or purchase higher capacity vehicles, but I could be wrong.
If the line was ever expanded into a higher capacity true light rail system with dedicated ROW, would new vehicles need to be purchased or is there precedent to hitch these types of vehicles together, even though there’s all the wasted space in the operator cabs that are “in the middle”?
Thanks!
My opinion is that it would be very unlikely for any effective "expansion" of one of these vehicles to be accomplished. What he's talking about is this:
Note that the low-floor section is entirely carried between the two 'motor units', which already have a substantial extension to the opposite side of the truck pivot location to balance it.
Lengthening the low-floor section would require counterbalancing the motor units, changing their polar moment of inertia (likely for the worse!) if not requiring a very expensive structural change to their carbodies. If that were done, there *might* be a reason to implement a low-floor section forward of the truck, but this would likely overhang 'low' on curves and pose all sorts of traffic and lineside-obstacle 'interference'. It is also entirely possible that the truck design and primary/secondary suspension would not support 'active' load management outside the expected ("as-designed") load range, and would have to be changed, perhaps requiring extensive respecification of components in addition to reprogramming.
The alternative to 'hitching the vehicles together' is to run a couple of standards on shorter headways for the length of time there is a rush, and only MU a couple when large convention loads demanded a higher capacity for a particular "car". The theoretical 'loss' due to the facing cabs is relatively small compared to the usefulness of the cars 'as built' rightsized for most other potential traffic peaks at the times they are run. For grins you could calculate the additional wages for the period of the additional rush-hour crewing (net of all on-the-clock expenses) and compare that to a pro-rata amortized cost for the lengthening over the expected service life. I suspect I know how this would go.
The HOP rather famously has only five of these things (of an eventual 24) and not all that much track to run many more yet. It is hard for me to imagine a rush-minute (like Madison's) that would require substantially larger 'single' vehicles that then wouldn't be oversized the other 23.5 hours of each day ... the argument that applies in other contexts to larger articulated buses. I would have to look hard at the advantages of acquiring 'another' rather than perform capex expensively ... possibly a substantial fraction of the cost of a new standard ... to get something wrongsized for the rest of the operation.
Other 3 segment LRVs have added another center segment and an intermediate segment between the center segments, to form a 5 segment car. (although the architecture is different)
http://www.kinkisharyo.com/projects/jersey-city-nj-new-jersey-transit-njt-5-section-lrv/
MidlandMikeOther 3 segment LRVs have added another center segment...
The only problem here is that you'll have almost doubled the cost of a 'unit' by doing this, only to wind up with a big inflexible thing that will seldom run full.
What it would involve is a central new 'section' with a single truck, articulated to adjacent low-floor 'box' sections. I have a suspicion this might need relatively long overhang at the ends of this section to match the dynamic behavior of the 'cab' sections, but this could be modeled fairly easily; and, probably, some active suspension techniques used to make the thing work with short length (effectively the same spacing from truck axle to low-floor section as used for either "B-end") for near-term HOP speeds.
Something to actively consider and, perhaps, speculate on is just how large the two low-floor sections could be made before the 'center' truck needs to be motorized. It is at least possible that two 'existing-size' low floor modules could be accommodated for current service with the present motors and control system, perhaps with lower acceleration or achieved peak speed between stops. If not, the two modules for an 'expanded' car could be shortened somewhat, although you would want to keep commonalty on a 'production quantity' of similar modules.
I'd be interested to see exactly how the joint between the end units and the 'module' is made, to see how easy field changeover could be made between long and short configurations.
Contact Brookville, and you will find it was designed to be expandable.
I believe they have already designed the basic added center section(s), requiring only the additional details to match the customer's specific options and customizatoin.
Lots of European systems have expanded cars. In the USA, NJT has done so.
Dave, you being the historian on this page I was surprised you didn't reference way back to Boston's "two rooms and a bath" trolley cars!
I tried to sell my two cents worth, but no one would give me a plug nickel for it.
I don't have a leg to stand on.
DB, I think Milan's first articulated three-truck, two-body streetcars (now they have many, built as such with modern-looking bodies and resilient wheels, etc.) was made from two regular Peter Witt streetcars joined together above on truck. I think I rode it on a Jack May-organized ERA tour. I think Montreal did something similar, with one car made from two (not Peter Witts, rear-loading large two-man cars), that was assigned only to the Cartialville line.
It would seem that there should be a mix of various lengths. Take a heavy used rush hour train set of 2 longs and one short. Then on shoulder drop one long and have one long and on short. Then last of shoulder drop the short. Late night park the final long and pick up the parked short, Run short late night and maybe all night / Now each agency of course will have different peaks and valleys but this give rise to memory schedules.
That allows for much easier crew scheduling and runs just what is needed for the time of day. This would save on car and track maintenance saving electricity as well. Allows for round the clock maintenance as well on all equipment.
Some European systems do something like that, running an articulated six or eight axles, mu with a simple four-axle car on a route, and then using either but not both for light and lighter traffic. On some systems, however, the four-axle ars is only a trailer, so light traffic requires the articulated.
Round-the-clock maintenance? You mean RTC except for rush hours. When mainenance of the modular accessories can take place off the vehicles.
The advantage of running multiple units is the ability to add, subtract, of change out a unit quickly and easily as capacity or maintainance needs change.
Dave
Lackawanna Route of the Phoebe Snow
daveklepper Contact Brookville, and you will find it was designed to be expandable. I believe they have already designed the basic added center section(s), requiring only the additional details to match the customer's specific options and customizatoin. Lots of European systems have expanded cars. In the USA, NJT has done so.
Do you have more info on this? I appreciate all the input on my question. I see DSchmitt put together a Photoshopped concept of what an extended Brookville Liberty Modern might look like, but are there any official renderings that might convey this better?
It seems there's a mix of opinions on here of whether more frequent service would be the better option or an extended passenger cab for some vehicles would be.
Personally, I think it makes sense having LRVs with varying lengths in inventory, to use depending on hours of demand, especially since running another motorized unit isn't likely to be as enery-efficient as tacking on an extra cab or two.
I don't have the server bandwidth to adequately discuss Brookville's options and suggest you contact them directly.
What is cost effective for one system may not be for another. And for different lines in a large system. A lot depends on just where you place the second mu'd car during off-peak hours.
Go to my several two-or-three-year-old thread on Jerusalem Light Rail. Ridership is way over projections, now up to 140,000 rides a typical weekday. The 44 LRVs are Alstom Civitas 302a, much like the five-section, three-truck version used in Dublin -- Except that all twelve wheels are powered rather than eight and mu is installed. The idea was single-car operation off-peak and two-car operation during rush hours. After initial testing and just the very first day of operation, all revenue trips are two-car trains. The space of the inward facing control cabs is wasted and is often desirable as needed to somewhat reduce overcrowding. Overcrowding is defined here as one unable to board without resort to physical violence and thus waits (usually only six or eight miniutes) for the next train. As new lines open, possibly some may see single-car operation. Meanwhile, I hope the new equipment required for expansion is single-end for back-to-back operation and thus without wasted space, and with additional door area on each side. Or Red Line trains replaced by 22 11-section six-truck cars with 24 powered wheels.
As for crowding, well those familiar with rush hours on the New York City Lexington Avenue Express. 4 or 5, have a good picture. Possibly the 2nd Avenue subway has aleviated conditins, but I doubt it, taking most of its passengers from the 6 local.
I am from Milwaukee myself.
The city has a lot of potential with these things by using some of the abandoned RR ROW in the cities for express routing for LRV's. The former C&NW lakefront line ROW from the Art Center up to the East Side which is now a trail has tremendous potential as an express LRV corridor to downtown Milwaukee AND for a rapid transit way of connecting the East Side and South Side of Milwaukee.
Bottom Line is I hope they don't just restrict these new trolleys to mixed traffic street running only. They need to use center medians and other shortcuts to cut transit time over long distances, in my view.
CMStPnP I am from Milwaukee myself. The city has a lot of potential with these things by using some of the abandoned RR ROW in the cities for express routing for LRV's. The former C&NW lakefront line ROW from the Art Center up to the East Side which is now a trail has tremendous potential as an express LRV corridor to downtown Milwaukee AND for a rapid transit way of connecting the East Side and South Side of Milwaukee. Bottom Line is I hope they don't just restrict these new trolleys to mixed traffic street running only. They need to use center medians and other shortcuts to cut transit time over long distances, in my view.
I hope they can do so. Is it possible to recover former RoWs (like the CNW Lakefront line) to use for LRVs?
Greetings from Milwaukee!
Yes, you’re exactly right on this, and the city planned the initial routes with that sort of use in mind, I believe. Many of the stations are built in center medians and the stretch running along Kilbourn Ave is entirely in a dedicated tramway that is outside of other street traffic. If you look at much of the system, you can see that the city could pretty easily dedicate most of the rest of the line in its own tramway by simply removing the parking lanes along some of the streets it is running, which would then allow for an a center-running separates LRT tramway, a vehicular lane and a protected curbside bicycle lane (or cycletrack) going in each direction.
I say “simply“, from a planning, engineering and design perspective, although eliminating parking lanes in Milwaukee is a bit taller of an order when it comes to political will to make it happen. Not impossible, as there is a BRT being built which will take out some parking lanes, but you still have many businesses that need convincing that parking lanes are often a massive waste of space and could be much better used for dedicated transit-ways.
The existing C&NW ROW you mentioned is a popular bike/ped path but there is definitely space available for rail to be added along it again, as well. It would indeed be a perfect connector for N/S transit in addition to the high value it currently serves as a commuter route for bicycle traffic.
Lincoln Memorial Drive could also use a road diet and one side could be N/S automobile traffic and the other side could be converted to a transit way serving a similar purpose.
As soon as you mix LRVs with rubber wheeled traffic, the advantage of rail is lost. You might as well use a bus. The capacity of the road is reduced, the LRV becomes an obstruction to the traffic and the rails prevent the LRV from navigating around the inevitable obstructions that will occur.
Not true. Depends on block spacing, traffic mix, lots of factors. Above about 25,000 passengers each way each day, a street railway, even sharing a traffic lane. is more economical in long-term costs because mainly of the much higher maintenance costs of diesel buses as compared with electric rail cars and their considerably shorer life-span. The largest diesel buses can handle about 150 people under crush-load conditions, where a double-articulated streetcar can handle 250, and one man is required for either.
But the point is valid that shared lanes with auto traffic should only be a last resort for an efficient light crail system. The streetcar routs in West Philadelophia benefit from a rapid-transit-like entrance to the downtown area. That means that the most congested streets are avoided. Boston's E line outer portion, from Brigham Circle to Heath Street, is the only shared-lane regular service trackage in the Boston system, and the other shared-lane tracks on on Chestnut Hill Avenue beween Beacon Street and Commnwealth Avenue, pull-ins and put-outs.
Most new streetcar systems, as opposed to light-rail systems, seem to have as a major goal something other than transportation. The streetcar fulfills these roles while bus does not seem to be able to do so. An attraction in itself.
daveklepper Not true. Depends on block spacing, traffic mix, lots of factors. Above about 25,000 passengers each way each day, a street railway, even sharing a traffic lane. is more economical in long-term costs because mainly of the much higher maintenance costs of diesel buses as compared with electric rail cars and their considerably shorer life-span. The largest diesel buses can handle about 150 people under crush-load conditions, where a double-articulated streetcar can handle 250, and one man is required for either. But the point is valid that shared lanes with auto traffic should only be a last resort for an efficient light crail system. The streetcar routs in West Philadelophia benefit from a rapid-transit-like entrance to the downtown area. That means that the most congested streets are avoided. Boston's E line outer portion, from Brigham Circle to Heath Street, is the only shared-lane regular service trackage in the Boston system, and the other shared-lane tracks on on Chestnut Hill Avenue beween Beacon Street and Commnwealth Avenue, pull-ins and put-outs. Most new streetcar systems, as opposed to light-rail systems, seem to have as a major goal something other than transportation. The streetcar fulfills these roles while bus does not seem to be able to do so. An attraction in itself.
Agreed. Also, there's a permanence to any fixed-rail transit that statistically draws more ridership than rubber-tire busses do, even those with dedicated lanes.
Riders, especially new riders, prefer to use a system with explicit and clear permanence. Bus routes are too often changed due to construction or for other reasons, and bus stops can be as temporary as a corrugated plastic sign zip-tied to a light post flapping in the wind.
That's not the kind of high-quality transit that most urbanites prefer to rely on. Rails in the ground, whether in mixed traffic or not, are preferred by most riders over busses. Also, rail transit offers a much smoother ride than any bus you'll ever board, and it's also typically faster, on average, as the lines are clear and the vehicle doesn't have to weave back and forth to the curb at every stop like busses do, jostling passengers and slowing the bus down considerably.
Obviously, the ideal is to have as much dedicated ROW space for the LRVs as possible, but even still, rail is the better option over busses where possible.
Light rail seems to fall somewhere between rapid transit and streetcars based on operating characteristics. Its best application would be as an arterial express route with a separate right-of-way, street operation being a last resort. Street operation is not appreciably different from buses, the main difference being that passengers on light rail would have to board from a safety island in the middle of the street rather than curbside for buses.
There seems to be a cultural bias that relegates bus transit as being too plebeian and assigns a certain amount of snob appeal to light rail and commuter rail.
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