Small trains and small stations are good until they aren't, and then you're screwed.
Singapore built the orbital Circle MRT line exactly as the author wants: small trains (3 carriages, vs 6-8 on other line), small stations to fit these trains, frequent fully automated operation.
However, the line turned out to be much more popular than planners anticipated, with the result that at rush hour, it's common to have to queue just to enter the platform where you need to wait for multiple trains to arrive before you can squeeze in.
And the tricky bit is that there is essentially nothing you can do now to fix it. There's a hard physical limit (around 90 secs) on how fast the cycle of a train arriving, people getting on and off, and departing can get, and retrofitting all 30+ deep underground stations to be larger would be an insanely expensive and disruptive exercise.
That's true, but if you've kept a lid on construction costs as light metros tend to do, the public will embrace building new relief lines that bring more service to areas with moderate access. That adds big capacity you can then continue to grow into. Paris is a great example of this, they often just add whole new lines rather than trying to wring a bit more capacity from existing ones.
You can build another line. This one was cheap and the demand is clearly there. And two medium capacity lines are generally better than one high capacity line in terms of offering more options to travelers.
It is much more expensive to build another line at that point due to the increase in density of the city (and sometimes new requirements of stations to meet building codes). Nearly every high volume transit system out there has choke points that are extremely expensive or impossible to fix by building another line. The tunnel between VA and DC on WMATA’s Orange, Silver, and Blue lines is a 20 year project. Tracks for LIRR to go to Grand Central took 60 years from proposal to opening. It is viewed as nearly impossible to build a line parallel to the MBTA underground green line, a system that has short two car trains and 4 branches above ground on the Boston side, so very easily could use a parallel line.
Singapore started building MRTs in 1982 and essentially never stopped. However "just build another line" is a bit glib when you're dealing with a city state of 6 million people on an island roughly 40km x 20km. There is a huge opportunity cost if land is misused or underused.
Well, at least we are putting our trains either on Pylons or underground. But you are right about opportunity costs nevertheless.
Also to add: building a high capacity line (say with 2x the capacity of the Circle Line) doesn't take 2x the land. There are obvious economies of scale.
Building two lower capacity lines has some diseconomies of scale, as the opportunity costs of the land use mount.
Singapore's MRT lines are some of the most expensive public transport projects ever. The Circle Line, fully automated and fully underground, cost S$10 billion[1]. The recent Thomson-East Coast Line, still partially under construction, is projected to cost S$25 billion[2]. It was not 'cheap' by any means.
> You can build another line
Singapore is building another line: the Cross-Island Line[3]. It has planned or is constructing at least three more lines[4][5] to achieve something like 460 km by 2040, thereby exceeding the length of the London Underground. About S$100 billion is earmarked for public transport expansion.
But the Circle Line was, as someone who has used it ever since it opened in 2009, ill-conceived as a 'small line'. It is heavily overcrowded. Because of the immense traffic and somewhat lacklustre maintenance, it has suffered several delays and breakdowns. The ideal thing for LTA to do would be to expand each station's capacity, because it links all of Singapore's radial lines at heartland residential areas.
A similar thing happened with SkyTrain's Canada Line, where it reached capacity very soon after it was built. They did plan a contingency to be able to extend the platforms for somewhat longer trains, however.
Canada Line is a bit weird since it wasn't built by Translink and doesn't use the same technology as the rest of SkyTrain. It was under built by the P3 out of caution for opening in time for the Olympics and extreme cost control, but they were really pessimistic in ridership projections. It was always going to burst at the seams pretty quickly, especially with all the transit oriented development along the route. It should have been built to the same ~80m platform as the rest of SkyTrain.
My ideal default rapid transit buildout for midsized urban areas would basically be SkyTrain with value engineering to extend the platforms to 100 or 120m with minimal cost in the future.
> and retrofitting all 30+ deep underground stations to be larger would be an insanely expensive and disruptive exercise.
But before this you had no idea that there was so much demand, right?
It's quite a lot easier to sell a huge monetary upgrade on something oversubscribed rather than a huge monetary outlay that may be a complete white elephant.
It's an order of magnitude easier and cheaper to dig out a 6-car platform the first time around than to expand from 3 to 6 when the system is already operational. And it's a one-off price too: if the platform is built but not used, it incurs essentially no operating costs to have it sit there waiting for the day it's needed.
Everything you said is completely orthogonal to my statement:
"It's quite a lot easier to sell a huge monetary upgrade on something oversubscribed rather than a huge monetary outlay that may be a complete white elephant."
A better solution that no one has the political will to implement is inferior to every solution that can actually be implemented.
It's not. These things become single point of failure for a city by the time these problems arise, and just can't be upgraded or replaced no matter the cost because they can't afford to take it offline for extended periods. "Too expensive" in these cases are just euphemism and technical disclaimer for something impossible.
Or rather politics often results in the implementation of technically inferior solutions. Sometimes the best solution is to do nothing and wait until the political will catches up to reality. Then you will be lambasted for not having acted sooner, but at least it will be done.
I think one solution is to embed a self-adjusting feedback mechanism into the transit fee.
- If the rush hour contines to get more crowded, the transit fee would raise until people avoid commuting on peak hours.
- If the rush hour disappears, the extra premium fee would fall to zero.
It is not unrealistic as it sounds; JR East (the biggest railway operator in Japan) recently introduced "Off-peak Commuter Pass", which is 1) 15% cheaper than a normal pass 2) and cannot be used between 7:30 - 9:00 AM.
So they are beginning to implement a dynamic policy based on how crowded their trains are.
I don't think that public transportation should strive to price out people of lesser means to fix demand vs supply problems. That's what Uber is for.
Of course it's fine to give people an incentive to ride outside of peak hours if they can, but demand is not that elastic, because of daily rhythms and how interconnected they are. Raising prices until you have removed the last option a lot of people have to get around, just so that others can enjoy their ride more, will remove a lot of opportunities from the economy.
I'd also be interested to know if the slack introduced by people moving their travel to off-peak times is not immediately taken up by others again, in the way that widening a congested road often just allows more cars to be congested at the same time. (Edit: Which can still be a good thing, especially for public transportation, because I'd argue that giving more utility to more people is its mission.)
I mean Japan is a obvious extreme what with the subway pushers and all.
Commuting times used to be rigid until COVID and the resulting WFH and hybrid policies showed corporate the world would not burn down if some people showed up at 800 vs 830 vs 930 vs 1000. Being in at 9am sharp it turns out is not a hard requirement for many jobs.
But that’s not what history shows us. The subway with the second most ridership in the US is WMATA. How did they get there? By going big with their plans in the 1960s. All the systems that thought small in that era (MARTA, BART, LA Metro) have much lower ridership to this day.
There is a good basis to this. Every new mile and station you add to a system compounds on the size of the system. The 11th station connects you to 10 places. The 51st station connects you to 50 places. Build small and you never get the critical mass needed to see widespread adoption.
What is the small aspect of BART? They have ten-car platforms and all that. ETA: the Internet thinks DC Metro platforms are 100 feet shorter than BART platforms.
BART has substantially less urban trackage than DC and cities have much higher transit ridership.
A more DC-like BART probably would have prioritized the second Transbay Tube and Geary Subway over the line to San Jose. BART did throw out the Geary baby with the bathwater when Marin County left.
The replies to this comment remind me that the supposed unavoidable law of induced demand evaporates pretty quickly amongst urbanists when talking about things they want to build. At the risk of sounding really snarky, “just one more line bro”.
> if we run a system for smaller trains, we can build smaller stations for these trains, saving a huge amount on station costs. This costs us in reduced total capacity, but this can easily be made up for by increasing train frequency.
There is a safe minimal distance between trains, in fact, a safe distance for a given speed. Shorter trains are not exempt from obeying it. You can make shorter trains more frequent at the expense of lowering traveling speed.
What is the cap of throughput is due to these speed limitations is an exercise left for the author of the article.
For capacity calculations, headway is what matters. E.g. trains spaced 2 mins apart means that 30 trains run in an hour.
It’s the same with cars. A 2s headway with cars holding 1 person each means that the maximum capacity of a highway lane is 1,800 people per hour, no matter how fast they go (the cars are further apart at higher speeds).
Freeway capacity is maximized around 35 MPH. Faster, and the greater distance between cars reduces capacity. Slower, and there are not enough cars per minute per lane. So the goal of ramp metering signals is to throttle input to keep the freeway speed around 35 MPH.
I think you would want to keep the road just slightly less dense (fewer cars, higher speeds) than the density that maximizes throughput, because otherwise you operate at the edge of an instability. Any tiny local deviation in speed somewhere triggers a slight local decrease in throughput, causing bunching which further decreases throughput and snowballs into a traffic jam.
When operating at slightly faster than max capacity, local slowdowns cause a local increase in throughput, allowing bunches to dissipate.
Doesn't really matter - in the real world everybody is tailgating. Drivers need to maintain 3 seconds (GP was using 2 seconds which safety experts have not declared too little) between cars for safety reasons. However drivers are instead maintaining more like .5 seconds between cars. As such nearly every city needs about 5 times as many lanes as they currently have when people finally start demanding "just one more lane"! 5 times - that puts Huston level freeways in Des Moines.
If you maintain the proper following distance at maximum capacity when there is an issue you can momentarily drop to 1 second (while braking) and then expand back to normal and there is no effect on traffic.
I'm going to double-down on this point because it does matter. In the real world some people are tailgating, but that does not cause traffic jams if and only if the road is running below peak capacity, where negative feedback self-corrects those traffic density deviations and gradually smooths everything back out. (Unless the tailgater causes a crash, of course).
But if the average following distance is such that the road is exactly at the peak of throughput, or any smaller, then any momentary dip into tighter following distances pushes the road it into a positive feedback operating mode, which triggers a traffic jam.
Interesting - I have believed for many years that it was around 17 MPH. I felt that this tallied with my observations - as traffic levels increase, vehicles slow down (increasing total capacity) until it falls to a critical speed (when slowing down reduces capacity) and then it changes to stop/go.
In my experience (on UK roads) this critical speed is around 17 MPH - but it might be a little different elsewhere.
Freeway capacity chokes at the limit giving rise to basically overpacked lanes slumping from metastability; systemic control with ramp meters or I66 (within the Washington D.C. Metro area) style real-time dynamic pricing lets freeways flow properly around peak capacity if properly implemented.
There are roads that regularly suffer from acutely insufficient capacity in many metro areas; specifically, repeatedly at times _the dynamic pricing toll that would discourage enough people from using it to stay uncongested_ would overshadow the price of a rental-with-driver (Uber-style) during off-peak times.
It's not that the people shouldn't get through; it's that most people won't need more than a backpack worth of luggage with them and could thus be packed 3~4 passengers for each driver.
Splitting the toll would be the reason to do so.
Unfortunately only really dynamic congestion tolls would really fix the concept of rush hour traffic jams. And the necessary surveillance system would bring severe mass surveillance/tracking concerns with it at least in central Europe.
I don’t think the surveillance needs to be cameras, a combination of radars (for velocity) and induction loops or the axle-counting rubber hoses (for counting) should do the trick
That's more of an illustration that throughput isn't something people want than an illustration that throughput is higher at 75 than at 35.
You see a lot of blanket assumption, in discussions of traffic, that throughput should be maximized, and almost no examination of whether increasing throughput is a goal that makes any sense.
For example, working from home has catastrophic effects on throughput.
> What is the cap of throughput is due to these speed limitations is an exercise left for the author of the article.
They already did that exercise:
> 3-car trains running at 30-40 trains per hour (a normal peak frequency for automated or even some human-driven metro lines) reach a capacity of about 18,000 passengers per hour per direction, well above the expected demand of any American line that doesn’t go through Manhattan.
40 trains per hour is in fact not "normal", but extremely difficult. Only a few systems in the entire world operate more than 30 per hour.
The fundamental constraint is not technology, but people and physics: you need to decelerate and stop, let people disembark and get on, accelerate and clear the platform. This cycle requires a bare minimum of 90 seconds, although IIRC a few lines in a few places like Paris and Moscow do 85 secs.
Indeed, the Victoria line in London manages 36 TPH and we've not bothered beating it since. It's much easier to run 26-30TPH with slightly more carriages.
> the Victoria line in London manages 36 TPH and we've not bothered beating it since
That was a world record for a line following modern safety standards, set less than 10 years ago. It's hardly a case of "not bothered", it's just hard.
90 seconds is very possible in new-build lines which is what the author is talking about. You can buy a turnkey Innovia (e.g. Vancouver Skytrain) or AnsaldoBreda (e.g Copenhagen) that does this out of the box. Retrofitting 90s operation is basically impossible but not the point of this exercise.
Yes, they are assuming a best-case scenario. Driverless systems are very expensive for reasons that have little to do with the cost of the driverless trains, if you're not going to consider those variables this kind of armchair speculation is a waste of everyone's time.
They aren't though? If you're building a new line, fully driverless is pretty much the default these days, especially if the line is fully underground or elevated.
What is incredibly expensive, though, is retrofitting a line designed for manual operation to run automatically instead.
Well, a lot of systems exist that were initially designed for automatic operation but still end up becoming operated manually or partially manually due to safety concerns or politics. Washington DC Metro and BART are the two big systems I can think of that had this issue.
Both examples of Great Society metros that were on the bleeding edge of what was possible in the early 70s. Automatic train control advanced rapidly, with both Vancouver SkyTrain and London Docklands Light Rail being built in the 80s and operating driverless for their entire existence.
DC Metro just recently re-enabled full automatic train operation across all the lines in June.
I don’t think anybody has tapped into the forbidden magic trick of having CBTC broadcast position and velocity instead of position alone. For vehicle ACC at least, there is a safe region of velocity and follow distance where a following train can plan to enter the space where the lead train currently occupies.
I wonder if it's possible to run trains at higher speeds closer to each other using fixed brakes embedded near the tracks, similarly to how roller coasters often have mid-course brake runs that are only activated in emergencies when the train ahead unexpectedly slows or stops.
We're at the point where we could easily fit so large a fraction of the rail length covered/overshadowed by the train with https://en.wikipedia.org/wiki/Track_brake that we could pull around 4 G deceleration if we cover the bottom in that brake chains (chain strong; chain flexy enough to just wiggle over humps in the track).
> Wait times are the second-most underrated component in making metro systems effectively faster (right after street to platform time).
Street to platform time made using public transit annoying in several Asian capitals. Wait times are the main reason why I often hate traveling with public transit even in a city with one of the best public transit systems - if you aren't planning your life around the transit schedule, the wait time is essentially an unpredictable part of your travel time (and if you do plan around it, it's one more annoying thing to deal with).
If you leave your doctor's office, and you have a 10 minute train home that goes every 30 minutes, then you really have a 10-40 minute train home - so for practical purposes, you essentially have a 40 minute train. Once unreliability or delays become frequent enough to start being a factor to consider, this could easily turn it into a 70 minute train.
Another big factor is the time between the actual start/end of the trip and the nearest station. Even with near-zero street-to-platform time (e.g. busses/trams) and reliable, reasonably frequent public transit, once you add it all up, a bicycle often ends up being faster than even excellent public transit.
Munich is a counter example: It has many lines passing through (almost) 11 stations. They run at maximum speed of 40 trains per hour. It is a traditional block signal system with each block being shorter than a train - so they can run trains packed into tighter space. Each train opens left and right doors simultaneously so people can board and exit at the same time.
Boarding still takes time. It is overcrowded at rushhour and brakes down regularily (a train being at a station for too long blocks all proceeding trains).
And at Oktoberfest time, the stations are soo crowded that boarding takes longer.
Munich is planning on building a second subway route. It just does not have the money nor the space to build one. There has been discussion on building a second tunnel below the first, or on enabling the common train system for overflow by suburban trains -- by installing more signals to run more tightly packed.
The second route is currently being built in Munich [0], with work started in 2017. I recently watched a youtube video by The B1M about rail projects in Germany that included a long section about the currently ongoing works in Munich [1] that gives a good visual overview.
I feel like this is one of those articles that claims some clever idea on paper but without experience of how this would actually work IRL but IDK if the OP has more experience than me so I will assume the best.
Others have already pointed out some of the practical things that would limit what you can achieve with shorter trains like minimum headway between trains and the congestion that would occur after a delay where you would expect people to wait for maybe 10 short trains to arrive and depart before you could get on.
There are other problems. The cost of the smaller trains means if e.g. 2 carriages each, then every other car is a driving vehicle with motors and control equipment. On longer trains, this could be 1 in 3 or 1 in 4. Each of these not only requires regular maintenance (so that's doubled the maintenance requirements) but also creates massive congestion issues in maintenance yards. Commonly, 1 or 2 full trains fit in each siding so getting most trains out if e.g. one is broken down is usually easy enough. Imagine having to move 3 or 4 separate smaller trains out of the way, they are not automated in the yards.
Most people would be very unhappy knowing that they might be alone on a train, which is a main reason why operators are not quick to get rid of all staff. But currently, a single driver and conductor is close by for, maybe, 8 carriages. This would double if you needed a single attendent on each 2 carriage train.
The signalling is very heavily designed around traditional trains with its delay after passing a signal. 4 x 2 carriage trains would utilise more signalling capacity/time than 1 x 8 carriage train. If these were all coming from the same location and needed to return, that would also need a lot more platforms so that the following trains don't block the first trains in terminal platforms. This is already a major problem at most UK terminal stations so that is largely unsurmoutable.
I also heavily question the idea that station cost is largely dependent on platform length. On most surface stations, platforms are relatively easy to construct and whether they are 4 carriages or 12 carriages long still require a station building or 2, some ticket machines and CCTV etc. For elevated railways that is more likely to be true maybe.
So yeah, like someone else said, we are unlikely to come up with ideas that 1000 other engineers haven't already asked, the easier problems to solve are around planning, design, legal rights for infrastructure projects etc. since these tend to eat up sometimes decades and billions of dollars.
Of course coming from the UK there is nothing that strikes horror into my heart more than being at a crowded platform waiting for a late train and it pulling up with half or quarter the carriages that you expected. Feels like a luxury to imagine a system where you’d get to tweak these variables until things work rather than trains being a force of nature.
Something I've been thinking about lately is short trains but long platforms. Basically, you split the length of the trains in half and then split the platform into two boarding areas. In this way trains can be scheduled even closer together than the the 3-min physical limit of of signalling because the one coming in behind doesn't need to wait for the one ahead to leave the station first. Its therefore possible to schedule several different services on the same two-track system such that they all skip a large fraction of stops (and thus run faster), but every station is still reachable from every other without transferring.
A simple example would be 3 services on the same line that follow a repeating pattern every 3 stations. ==[A]==[B]==[C]==[A]==[B]==[C]==. The service (AB) stops on the stations labelled [A] and [B] (skipping C). The service (AC) stops on the stations labelled [A] and [C] (skipping B). The service labelled (BC) stops on the stations labelled [B] and [C] (skipping A). In this manner, all three services skip over 33% of the stops on the line, but no matter what your origin and destination, it is always possible to travel from an [A] station to a [B] or [C] station (or another [A] station), and likewise from a [B] or [C] station.
To the extent I've worked out the logistics of this, if you allow for trains to catch up but not pass each other at the platforms, you can push this idea as far as only stopping at 2-in-5 stations without sacrificing headways or capacity.
Just a weird thing thats been taking my attention lately.
In a lot of train systems this exists in the form of fast / stop trains, the fast trains only do the bigger train stations, the stop trains stop at every station, servicing smaller stops.
As for short trains on long platforms, this is pretty common in NL where the bigger train stations can support both very long international trains and shorter local trains on the same platform; a train can switch to a center track halfway on the platform.
I don't think it would really work for a subway system; people expect it to be hop on, hop off. In some places the stops (or people's final destinations) are so close together they can choose to get on/off earlier/later, but this system makes that less viable. You'd have more people shuffling through train stations trying to figure out which train to get or whether they need to wait for the next one, also putting extra load on staff for confused not-locals. And finally, you'd need extra rails or tunnels so that a train can pass another.
How would that help? 3 minutes is the minimum separation distance, if the trains have different stopping patterns then that just means they'll be further apart for part of their journey. If you have to stay 3 minutes behind the train in front, you might as well stop at all the same stations that it does, you can only save time if you were further behind to start with, so you can't increase throughput by skipping stops.
Simplifying a bit, its because the train behind can be scheduled 3 min after the train ahead has pulled in rather than 3 min after the train ahead pulled out. Put another way, the safe stopping distance to maintain (while at speed) would be measured from the half way point of the platform rather than the start of the platform.
This lets you schedule them much closer together than the conventional 3 min while still being safe.
> its because the train behind can be scheduled 3 min after the train ahead has pulled in rather than 3 min after the train ahead pulled out.
Why? If the minimum is 3 min then it's 3 min (at least with a modern moving-block type setup). If it's safe to run them 2 min apart it's (generally) safe to run them 2 min apart the whole time.
I feel as if the time spent by each passenger walking to the right boarding area could easily surpass the dwell time of an extra stop or two.
Consider a metro system with trains 70 m long. With 10 m of space between the two boarding areas, that means the length between both sides of the station is 150 m. If the entrance to the platform is in the center, the walk to the middle of each boarding area is 45 m, taking about 30 seconds. If the entrance is at the end, that becomes 35 m or 115 m (taking about 20 to 90 seconds to walk). I think those figures are comparable to the dwell time of a typical metro system.
I do think it's a very interesting idea though! I think it'd work better for longer trains over longer distances, where the time spent accelerating and braking is often greater, but unfortunately few places are even considering anything shorter than 15 minute headways for such rail services.
Admittedly my calculations did not take walking-on-platform time into account, but what I have been assuming (based on figures I've looked up) is that each stop adds about 60 seconds to the journey time (30 seconds for dwell + 15 on either end for getting up to / down from cruise speed). I've also been assuming that the inter-station no-slowing-down time is 2 min.
So in a 2-of-5 stopping pattern you'd save 3 min every 5 stops, but depending on when arrive at the station you will sometimes get unlucky and just miss your train, in which case you'll have to wait an additional interval than you normally would for the next one (costing you 3 min). So for very short trips (under 3 stops) it actually makes travel time a bit worse since there's very few stops you can skip over in such cases. But for more median trips there is a saving, and for the longer trips it saves well into 2-digit minutes.
In your example I think in the case with the entrance at the middle of the platform there wouldn't be any real effect, because splitting the platform also in the middle doesn't marginally change how quickly you can get to the nearest open door on the train you want. There's no real need to get to the center of either boarding area. In the case of platform at the end of the station, I can accept that adds about 40 m of walking distance that wasn't there before (at least for some people), and that translates into an extra 20ish seconds. Less than that if you do the rational thing of walking briskly when you see you're about to miss your train.
So you're right that the platform split adds some time which isn't completely negligible, and depending on what fraction of the next n stops you want to skip it comes at a penalty of longer wait times for the correct train, but both of these are fixed upfront costs whereas the dividend accrues linearly the longer your on the train.
This is how it already works in Europe (at least in Austria and Germany, but I assume elsewhere in Europe as well).
You will also find long trains that split in half mid-journey, so you need to make sure you get in the right car or you'll go to the wrong place.
Edit: I guess it's not exactly what you're saying, in Europe you will find platforms split into several sections with multiple trains to board, but they'll be for different lines with different destinations.
The author spends a lot of words talking about short trains and Jersey City, but didn't once mention the Hudson Bergen Light Rail which was at least built in recent memory? I mean other than driverless operation it seems to check all the boxes. And in that light, I really fail to see the novelty in this argument; it's basically the multi-decade-old argument that building light rails is cheaper and better than real metro or heavy rail.
there is nothing new about trains - we need to stop looking for innovation and just build them with small incremental improvements. The only useful innovation since 1920 is full automation (though I'm going to call high speed rail incremental since it is mostly a lot of small improvements on the way - this is debatable). Even full automation was a lot of incremental improvements.
That said, full automation is a major game changer because it enables short trains with high frequency which you would otherwise struggle to afford. Don't build light rail, build light metro which is a small cost more (build a metro with light rail) but now you can have full automation.
I also thought this omission was conspicuous. The author has some reasonable points, but the sections on NYC and NJ felt like political wish (spite?) casting: just about the only state in the US that struggles more to build mass transit than NY is NJ. The HBLR is a rare survivor in an otherwise very crowded graveyard of NJ mass transit projects.
Loebner (of the prize fame) patented the idea of a rollercoaster tube system. Stations on the surface, going underground and up to the next station. Saves power and reduces the curb to platform time. Just thought I'd put that out there...
But then you'd need stations and part of the rails on the surface, taking up valuable real estate. Versus a small entrance building. Not sure how or how much it would save power either.
I don't think there is any danger to running more frequent longer trains. Ultimately you are constrained by the signalling system; nobody is suggesting "just disable the tripcocks and plow through red signals". Modern systems use moving block cab signals, so are set up to succeed with high frequency. (But there are other problems, like terminal capacity, that can limit frequency. The MTA in NYC spent a ton of money giving the L CBTC to run 40+ tph... but the terminal at 8th Ave can't turn that many trains. Until that's fixed, the L will always be overcrowded.)
You can see whether the problem is being cheap or if it's actually a capacity issue. If weekend service sucks but peak hour service is good, then it's just being cheap. If rush hour can't handle passenger volumes, then you need a signal system / automation upgrade. (Or a parallel line!)
As a New Yorker, I'm very jealous of Vancouver's SkyTrain system. ("But NYC has the best metro in North America!!" Maybe...) The NYC subway has a lot of peak hour capacity. I hate traveling at peak hours. So that means I'm always standing in stations waiting 10 minutes for the next train. If I lived in Vancouver, then that would be 3 minutes. Sounds good to me!
I also agree with the author in that I'm not sure what elevated trains did to hurt people. I lived in Chicago next to the L for years. It never bothered me. It's nice to see out the window and look at something while you're in transit. And it's cheaper than building things underground. NYC apparently got rid of its elevated railways because of snow, so that's something to watch out for. But Chicago gets more snow and it does OK. (Having commuted on both systems in the snow, it's a mixed bag. Chicago doesn't shut down, but it's slow as people remember how to deal with snow. NYC can run on snow-free underground tracks, but sometimes the governor is like "fuck it, I'm cancelling all the trains anyway" and then you're just stuck.)
SkyTrain vs Seattle Link Light Rail is a fascinating contrast.
SkyTrain works because of a virtuous cycle of attributes:
Full grade separation enables automation. Automation enables many trains per hour. Many trains per hour with short trains still has tons of capacity. Short trains means lower costs for stations, which as the article notes is a huge portion of rapid transit costs. Lower cost means building more transit for the same budget, so more transit gets built. More transit with great headways results in transit being the mode of choice. Take any one of these elements out and you can still have a functioning transit system, but the magic is missing.
Link light rail is so close to full grade separation but not quite there, so headways are limited by the grade crossing. With longer headways, bigger trains are needed to serve the same capacity. Bigger trains mean big stations and beefier, more expensive viaducts. Big stations are expensive.
Link is gaining ridership and offering great service, but it's hard not to think if they had learned the full lessons from nearby Vancouver it would be even better (and cheaper).
> I also agree with the author in that I'm not sure what elevated trains did to hurt people.
They're horrifically ugly for pedestrians and city life generally. If you've been around the elevated subway tracks in Brooklyn, for example, they're not pleasant to be around. They block out the sun, they're incredibly noisy, they make the street claustrophobic, they definitely become streets to avoid unless necessary.
Yes, they have a nice view if you're a passenger. But they make the city much, much worse for everyone below them.
Oh yes. In Manhattan there were plenty of elevated lines that were dismantled because the people thought that they were too noisy and should be replaced with subways. The Second Avenue had an elevated train that was supposed to be replaced by a Second Avenue Subway, but the latter is only partially complete.
The elevated steel structures of the NYC subway and Chicago El have nothing in common with modern elevated rail. Modern concrete guideways are small and quiet.
Melbourne is eliminating grade crossings with new guideways and creating linear park space underneath as they go.
> I also agree with the author in that I'm not sure what elevated trains did to hurt people.
You need to either build them in right at the start of a new development or you gotta demolish a lot of housing - similarly to what was done in a lot of US cities when the highways were built [1].
> I also agree with the author in that I'm not sure what elevated trains did to hurt people.
I've only seen them in Hamburg. They are generally an eye-sore. And the area underneath them is somewhat unusable (like any area under a bridge): you can't really build anything there. So it's an eyesore above an eyesore.
There are plenty driverless trains in operations. Some have been running for decades. For example Toulouse in France has a metro without drivers since 1993. I was there a decade or so ago and sat in the front of the train on a bench in the front of the train staring out into the tunnel. Because there isn't a driver compartment. Really cool. They have some fences on the platform that align with the train doors for safety. The train lines up, people get in/out and it drives to the next station. Some airports have similar systems. This stuff has been possible for quite some time.
These days, you should be designing for autonomous operation for new infrastructure. Much easier when you design from the ground up. Not doing that could be an expensive mistake.
I mean this is talking about construction of brand new lines, and in the Western world if you are building a brand new, totally separated line then automated is the no-brainer solution given high Western labor costs.
Automation with short trains is similar price to long trains, but the short trains will run a lot more often and that will attract riders who have a choice of driving or not. If they miss their bus/train or have a long wait for their bus/train they will fix that by driving. However if they try transit and service is frequent they will realize that transit works just fine and so they will choose to not drive even though they can.
It's not written in stone, but if you don't, people will be moving through the train and pushing to get out sooner. Public transit is a test of patience and a study in human herd behaviour.
> Is it written in stone that a train must fit entirely into a station so that all doors face the platform and can be open simultaneously?
When you're building high capacity transit for dense cities, yes. You could stop the train twice in the same station, sure, but at that point you have to stop for twice as long (probably a little longer than that as your riders will get confused), so your train takes ~twice as long to get anywhere and can therefore carry ~half as many people.
The moment you have only some cars platforming, then people need to make sure they are in the right car, and if, say, a slow-walking elderly person is in the wrong car, then her getting into the right one to get off wastes a lot of time.
it's all about capacity requirement. If the capacity demand is high, you might want to build really long trains and run them as frequently as possible (e.g. Istanbul Marmaray)
Why are tech dudes so hung up on homelessness? Also, the reference to it was so callous and would seem to reveal a complete lack of empathy: NYC has too many homeless people; let's build a metro in Jersey City in order to make Jersey City ... more of a thing and not even attempt to address the "problem" in any substantive way.
It's also a feat of mental gymnastics to put European infrastructure on a pedestal while ranting about NY's taxes and, more broadly, the US' difficulties building infrastructure.
Compared to car traffic, rail is a lot nicer. Putting it in place is indeed disruptive; just like any kind of infrastructure work. Once you have it, property values tend to go up, not down due to better transport options.
In a few years I think we'll recognize that self-driving vans (in a few different sizes) are the best trains: cheaper than trains (and therefore lower environmental impact), completely flexible routing, and you can even let them use dedicated right of way if you want to increase capacity.
Most suburbs are dense enough to have demand for full sized buses if service is good. The cost of a bus means that cities don't give them good service, but automated bus drivers would reduce the costs enough that they could run good service and this in turn will get so many people to use the bus instead of driving that the van could not work.
For rural areas a van might make sense, though you quickly get to a frequent van is less efficient than just owning your own van.
Yep, but I think automated bus drivers change the math. A standard-ish city bus is $1M and seats 50 (though they're rarely full). You could definitely get 5 vans that would seat 6 for $1M. Absolute seating capacity is lower, but total throughput could be greater because of the extra flexibility.
Smaller vehicles allow more dynamic dispatch. SF buses are low quality transport because they have to stop every block to allow for an elderly local population. With vans, you can put more of them on the road and dynamic dispatch allows them to skip stops for non-loading.
This structure allows for greater QoS through the system. Almost any sufficiently dense place without regulation limiting it approaches a mix of larger buses on fixed routes with smaller vehicles on slightly less fixed routes.
SF Muni has a 13% absence rate. Without the driver we can have more vehicles, more often, and on-time every time. Once we can do that, we can vary the size of the vehicles to cover different routes and to allow for QoS.
That is a horrible idea and shows how little you care or think about bus riders. Bus riders need predictable. If the but has dynamic dispatach you can't trust it will get you there on time. We need predictable routes with minimal variance so everyone gets predictable. Good qos is predictable.
I don't think you read what I said. It's about combining fixed routes with flexible. But also this is clearly a religious subject for you, so perhaps it's better to call an end to the discussion.
> cheaper than trains (and therefore lower environmental impact)
How does that work? For the same amount of capacity, vans are not and probably never will be cheaper. Steel wheels on rails, with massive capacity, is just drastically more efficient, even with 0 driver costs. You'll still have much more maintenance (the tires, breaks, road) to do with a much higher number of vehicles.
I've yet to see a convincing argument that trains are cheaper than busses (especially when you consider that most of a bus's route (in the USA) would be on "free" roads).
Trains can certainly HOLD more people than a bus, and I hate buses with a passion normally reserved for religious arguments, and trains are Choo-choo, but they are expensive as all hell.
If the bus is using "free" roads, then it's forced to compete for space with general traffic and likely to perform far worse than BRT or trains that don't have to do this. Worse performance/speed/frequency => lower ridership => worse profitability => calls to cancel the "wasteful" bus etc.
The only way out IMO is that we have to stop ripping off the public by giving away unlimited road space for free.
> I've yet to see a convincing argument that trains are cheaper than busses (especially when you consider that most of a bus's route (in the USA) would be on "free" roads).
For a given capacity requirement, in a dense city, they're cheaper. The biggest costs of an urban train line are 1) building stations on expensive land 2) driver salaries, and buses are worse on both aspects; you need much more station space to load/unload the same number of people from buses than from trains, and buses carry far fewer passengers per driver.
> If they weren't why would BRT exist at all?
As far as I can tell BRT is a spook, a way for the road lobby to stop cities building rail. Has it ever actually worked out well for passengers?
Bus lifespan is 15-20 years max and needs tons of maintenance during that time. Trains last 40 years and go 100,000 miles+ between failures.
Trains are a bigger upfront investment, but are cheaper in the long run, especially once capacity is factored in. You need a lot of busses to equal moderate sized trains.
Busses have their place, but not as the backbone for rapid transit in even moderate sized urban areas.
BRT trades CAPX for OPEX. In Latin America where BRT is hugely successful capital is expensive and labour is cheap, so hiring a ton of drivers is easy. In high labour costs markets like the US, Canada, and Europe BRT falls apart. It's often all transit agencies think they can get funding and support for so it's pushed, but it's way too easy to cut back BRT attributes like signal priority, dedicated lanes, and all door boarding to end up with just a bus with a fancy livery.
It's quite easy to make a profit from a bus system that operates in peak commuter hours on peak commuter routes. It's virtually impossible to make a profit from one that has a public service obligation.
The key benefit of BRT is that they have a dedicated right-of-way without conflicts with other traffic just like train tracks with full grade separation. So to do that, BRT suddenly no longer has free roads. You now need dedicated BRT-only roads.
This will depend on density and what's already built. An extreme case: it wouldn't make sense to replace a large, rural school district's bus fleet with trains.
All trains, tracks, and stations are specially designed and built, which makes them very expensive. There is no mass-produced off-the-shelf solution like with cars and roads.
Trains are unbeatable for inland freight between limited destinations, but don't make much sense for current day commuting or traffic patterns.
This is not really true. There are absolutely things in the rail system that are as “mass produced” as roads are. Railway platforms for example are a highly standardised form that has many other applications (loading and inspection bays, walkways etc.), trains are actually not only mass produced (e.g. by Bombardier) but are actually leased by their operators in Europe; there are five or six, I think, main ROSCOs —- rolling stock companies —- in the UK for example.
There is a notable exception that might distort techie perception on this issue: BART. It implements many of its own standards, even down to track gauge. But it is absolutely an outlier (standardised track gauge, ironically, being the USA’s main contribution to the development of the railways, which it was otherwise late to).
Almost everywhere else has rather interchangeable infrastructure and a lot of trans-national businesses.
> but are actually leased by their operators in Europe; there are five or six, I think, main ROSCOs —- rolling stock companies —- in the UK for example.
Nah, this is a UK absurdity because they UK decided to privatise their railways in the worst possible way - every single part (rail infrastructure, operations, rolling stock) was privatised in a local monopoly manner. The rolling stock owners could lease to multiple different operators, so there was some limited competition on that front (probably eviscerated by the need for the ROSCOs to have a profit margin, on top of the fact that there were 10 of them, which meant reduced economies of scale both at acquiring but also maintaining those trains).
They're currently trying to nationalise some parts, after already nationalising the infrastructure (because people died due to bad maintenance due to misaligned incentives - maintenance doesn't bring profits).
But other than that, rolling stock leasing mostly exists in freight.
> trains are actually not only mass produced (e.g. by Bombardier)
But yes, trains of all types are mass produced by companies such as Alstom (which were already massive and also bought Bomboardier's train arm), Siemens, Stadler, etc. They can be customised (size, features, etc.), but e.g. the Alstom Metropolis line of metro trains can be found all over the world.
There are off the shelf trains, tracks, and stations already. It's one of the key ways many european and asian operators deliver tons of transit for the dollar.
Small trains and small stations are good until they aren't, and then you're screwed.
Singapore built the orbital Circle MRT line exactly as the author wants: small trains (3 carriages, vs 6-8 on other line), small stations to fit these trains, frequent fully automated operation.
However, the line turned out to be much more popular than planners anticipated, with the result that at rush hour, it's common to have to queue just to enter the platform where you need to wait for multiple trains to arrive before you can squeeze in.
And the tricky bit is that there is essentially nothing you can do now to fix it. There's a hard physical limit (around 90 secs) on how fast the cycle of a train arriving, people getting on and off, and departing can get, and retrofitting all 30+ deep underground stations to be larger would be an insanely expensive and disruptive exercise.
That's true, but if you've kept a lid on construction costs as light metros tend to do, the public will embrace building new relief lines that bring more service to areas with moderate access. That adds big capacity you can then continue to grow into. Paris is a great example of this, they often just add whole new lines rather than trying to wring a bit more capacity from existing ones.
This makes a lot of sense to bring life to new districts naturally.
Look into Streetcar Suburbs for a American examples. You could do worse than starting with https://en.wikipedia.org/wiki/Streetcar_suburb
> essentially nothing you can do now to fix it
You can build another line. This one was cheap and the demand is clearly there. And two medium capacity lines are generally better than one high capacity line in terms of offering more options to travelers.
It is much more expensive to build another line at that point due to the increase in density of the city (and sometimes new requirements of stations to meet building codes). Nearly every high volume transit system out there has choke points that are extremely expensive or impossible to fix by building another line. The tunnel between VA and DC on WMATA’s Orange, Silver, and Blue lines is a 20 year project. Tracks for LIRR to go to Grand Central took 60 years from proposal to opening. It is viewed as nearly impossible to build a line parallel to the MBTA underground green line, a system that has short two car trains and 4 branches above ground on the Boston side, so very easily could use a parallel line.
Singapore started building MRTs in 1982 and essentially never stopped. However "just build another line" is a bit glib when you're dealing with a city state of 6 million people on an island roughly 40km x 20km. There is a huge opportunity cost if land is misused or underused.
Well, at least we are putting our trains either on Pylons or underground. But you are right about opportunity costs nevertheless.
Also to add: building a high capacity line (say with 2x the capacity of the Circle Line) doesn't take 2x the land. There are obvious economies of scale.
Building two lower capacity lines has some diseconomies of scale, as the opportunity costs of the land use mount.
> This one was cheap
Singapore's MRT lines are some of the most expensive public transport projects ever. The Circle Line, fully automated and fully underground, cost S$10 billion[1]. The recent Thomson-East Coast Line, still partially under construction, is projected to cost S$25 billion[2]. It was not 'cheap' by any means.
> You can build another line
Singapore is building another line: the Cross-Island Line[3]. It has planned or is constructing at least three more lines[4][5] to achieve something like 460 km by 2040, thereby exceeding the length of the London Underground. About S$100 billion is earmarked for public transport expansion.
But the Circle Line was, as someone who has used it ever since it opened in 2009, ill-conceived as a 'small line'. It is heavily overcrowded. Because of the immense traffic and somewhat lacklustre maintenance, it has suffered several delays and breakdowns. The ideal thing for LTA to do would be to expand each station's capacity, because it links all of Singapore's radial lines at heartland residential areas.
[1]: https://medium.com/from-the-red-line/was-the-circle-line-bui...
[2]: https://www.mot.gov.sg/news/Details/speech-by-minister-khaw-...
[3]: https://www.lta.gov.sg/content/ltagov/en/upcoming_projects/r...
[4]: https://www.lta.gov.sg/content/dam/ltagov/who_we_are/our_wor...
[5]: https://en.wikipedia.org/wiki/Mass_Rapid_Transit_(Singapore)...
A similar thing happened with SkyTrain's Canada Line, where it reached capacity very soon after it was built. They did plan a contingency to be able to extend the platforms for somewhat longer trains, however.
Canada Line is a bit weird since it wasn't built by Translink and doesn't use the same technology as the rest of SkyTrain. It was under built by the P3 out of caution for opening in time for the Olympics and extreme cost control, but they were really pessimistic in ridership projections. It was always going to burst at the seams pretty quickly, especially with all the transit oriented development along the route. It should have been built to the same ~80m platform as the rest of SkyTrain.
My ideal default rapid transit buildout for midsized urban areas would basically be SkyTrain with value engineering to extend the platforms to 100 or 120m with minimal cost in the future.
> and retrofitting all 30+ deep underground stations to be larger would be an insanely expensive and disruptive exercise.
But before this you had no idea that there was so much demand, right?
It's quite a lot easier to sell a huge monetary upgrade on something oversubscribed rather than a huge monetary outlay that may be a complete white elephant.
It's an order of magnitude easier and cheaper to dig out a 6-car platform the first time around than to expand from 3 to 6 when the system is already operational. And it's a one-off price too: if the platform is built but not used, it incurs essentially no operating costs to have it sit there waiting for the day it's needed.
Everything you said is completely orthogonal to my statement: "It's quite a lot easier to sell a huge monetary upgrade on something oversubscribed rather than a huge monetary outlay that may be a complete white elephant."
A better solution that no one has the political will to implement is inferior to every solution that can actually be implemented.
It's not. These things become single point of failure for a city by the time these problems arise, and just can't be upgraded or replaced no matter the cost because they can't afford to take it offline for extended periods. "Too expensive" in these cases are just euphemism and technical disclaimer for something impossible.
Or rather politics often results in the implementation of technically inferior solutions. Sometimes the best solution is to do nothing and wait until the political will catches up to reality. Then you will be lambasted for not having acted sooner, but at least it will be done.
The political will catches up a lot faster (if at all) when there's a practical demonstration of the thing to be achieved.
I think one solution is to embed a self-adjusting feedback mechanism into the transit fee.
- If the rush hour contines to get more crowded, the transit fee would raise until people avoid commuting on peak hours.
- If the rush hour disappears, the extra premium fee would fall to zero.
It is not unrealistic as it sounds; JR East (the biggest railway operator in Japan) recently introduced "Off-peak Commuter Pass", which is 1) 15% cheaper than a normal pass 2) and cannot be used between 7:30 - 9:00 AM.
So they are beginning to implement a dynamic policy based on how crowded their trains are.
I don't think that public transportation should strive to price out people of lesser means to fix demand vs supply problems. That's what Uber is for.
Of course it's fine to give people an incentive to ride outside of peak hours if they can, but demand is not that elastic, because of daily rhythms and how interconnected they are. Raising prices until you have removed the last option a lot of people have to get around, just so that others can enjoy their ride more, will remove a lot of opportunities from the economy.
I'd also be interested to know if the slack introduced by people moving their travel to off-peak times is not immediately taken up by others again, in the way that widening a congested road often just allows more cars to be congested at the same time. (Edit: Which can still be a good thing, especially for public transportation, because I'd argue that giving more utility to more people is its mission.)
I mean Japan is a obvious extreme what with the subway pushers and all.
Commuting times used to be rigid until COVID and the resulting WFH and hybrid policies showed corporate the world would not burn down if some people showed up at 800 vs 830 vs 930 vs 1000. Being in at 9am sharp it turns out is not a hard requirement for many jobs.
But that’s not what history shows us. The subway with the second most ridership in the US is WMATA. How did they get there? By going big with their plans in the 1960s. All the systems that thought small in that era (MARTA, BART, LA Metro) have much lower ridership to this day.
There is a good basis to this. Every new mile and station you add to a system compounds on the size of the system. The 11th station connects you to 10 places. The 51st station connects you to 50 places. Build small and you never get the critical mass needed to see widespread adoption.
What is the small aspect of BART? They have ten-car platforms and all that. ETA: the Internet thinks DC Metro platforms are 100 feet shorter than BART platforms.
BART has substantially less urban trackage than DC and cities have much higher transit ridership.
A more DC-like BART probably would have prioritized the second Transbay Tube and Geary Subway over the line to San Jose. BART did throw out the Geary baby with the bathwater when Marin County left.
The replies to this comment remind me that the supposed unavoidable law of induced demand evaporates pretty quickly amongst urbanists when talking about things they want to build. At the risk of sounding really snarky, “just one more line bro”.
> if we run a system for smaller trains, we can build smaller stations for these trains, saving a huge amount on station costs. This costs us in reduced total capacity, but this can easily be made up for by increasing train frequency.
There is a safe minimal distance between trains, in fact, a safe distance for a given speed. Shorter trains are not exempt from obeying it. You can make shorter trains more frequent at the expense of lowering traveling speed.
What is the cap of throughput is due to these speed limitations is an exercise left for the author of the article.
For capacity calculations, headway is what matters. E.g. trains spaced 2 mins apart means that 30 trains run in an hour.
It’s the same with cars. A 2s headway with cars holding 1 person each means that the maximum capacity of a highway lane is 1,800 people per hour, no matter how fast they go (the cars are further apart at higher speeds).
Freeway capacity is maximized around 35 MPH. Faster, and the greater distance between cars reduces capacity. Slower, and there are not enough cars per minute per lane. So the goal of ramp metering signals is to throttle input to keep the freeway speed around 35 MPH.
I think you would want to keep the road just slightly less dense (fewer cars, higher speeds) than the density that maximizes throughput, because otherwise you operate at the edge of an instability. Any tiny local deviation in speed somewhere triggers a slight local decrease in throughput, causing bunching which further decreases throughput and snowballs into a traffic jam.
When operating at slightly faster than max capacity, local slowdowns cause a local increase in throughput, allowing bunches to dissipate.
Doesn't really matter - in the real world everybody is tailgating. Drivers need to maintain 3 seconds (GP was using 2 seconds which safety experts have not declared too little) between cars for safety reasons. However drivers are instead maintaining more like .5 seconds between cars. As such nearly every city needs about 5 times as many lanes as they currently have when people finally start demanding "just one more lane"! 5 times - that puts Huston level freeways in Des Moines.
If you maintain the proper following distance at maximum capacity when there is an issue you can momentarily drop to 1 second (while braking) and then expand back to normal and there is no effect on traffic.
I'm going to double-down on this point because it does matter. In the real world some people are tailgating, but that does not cause traffic jams if and only if the road is running below peak capacity, where negative feedback self-corrects those traffic density deviations and gradually smooths everything back out. (Unless the tailgater causes a crash, of course).
But if the average following distance is such that the road is exactly at the peak of throughput, or any smaller, then any momentary dip into tighter following distances pushes the road it into a positive feedback operating mode, which triggers a traffic jam.
If you haven't seen it, here is a classic experiment demonstrating the effect: https://www.youtube.com/watch?v=Suugn-p5C1M
(But obviously the solution to traffic isn't 5 more lanes, it's viable alternatives to driving!)
This is a classic case of throughput v. latency - and most people are going to prefer lower latency, i.e. driving faster.
Interesting - I have believed for many years that it was around 17 MPH. I felt that this tallied with my observations - as traffic levels increase, vehicles slow down (increasing total capacity) until it falls to a critical speed (when slowing down reduces capacity) and then it changes to stop/go.
In my experience (on UK roads) this critical speed is around 17 MPH - but it might be a little different elsewhere.
Freeway capacity chokes at the limit giving rise to basically overpacked lanes slumping from metastability; systemic control with ramp meters or I66 (within the Washington D.C. Metro area) style real-time dynamic pricing lets freeways flow properly around peak capacity if properly implemented.
There are roads that regularly suffer from acutely insufficient capacity in many metro areas; specifically, repeatedly at times _the dynamic pricing toll that would discourage enough people from using it to stay uncongested_ would overshadow the price of a rental-with-driver (Uber-style) during off-peak times. It's not that the people shouldn't get through; it's that most people won't need more than a backpack worth of luggage with them and could thus be packed 3~4 passengers for each driver. Splitting the toll would be the reason to do so.
Unfortunately only really dynamic congestion tolls would really fix the concept of rush hour traffic jams. And the necessary surveillance system would bring severe mass surveillance/tracking concerns with it at least in central Europe.
I don’t think the surveillance needs to be cameras, a combination of radars (for velocity) and induction loops or the axle-counting rubber hoses (for counting) should do the trick
35? That seems too slow. Several years ago some pranksters in Chicago drove side by side at 55MPH and caused a MASSIVE backup for miles.
That's more of an illustration that throughput isn't something people want than an illustration that throughput is higher at 75 than at 35.
You see a lot of blanket assumption, in discussions of traffic, that throughput should be maximized, and almost no examination of whether increasing throughput is a goal that makes any sense.
For example, working from home has catastrophic effects on throughput.
> What is the cap of throughput is due to these speed limitations is an exercise left for the author of the article.
They already did that exercise:
> 3-car trains running at 30-40 trains per hour (a normal peak frequency for automated or even some human-driven metro lines) reach a capacity of about 18,000 passengers per hour per direction, well above the expected demand of any American line that doesn’t go through Manhattan.
40 trains per hour is in fact not "normal", but extremely difficult. Only a few systems in the entire world operate more than 30 per hour.
The fundamental constraint is not technology, but people and physics: you need to decelerate and stop, let people disembark and get on, accelerate and clear the platform. This cycle requires a bare minimum of 90 seconds, although IIRC a few lines in a few places like Paris and Moscow do 85 secs.
SEPTA's T [1] gets up to 70 TPH and used to handle 150 TPH. You can do this with multiple trolleys loading/unloading on a platform simultaneously.
(But this strategy is orthogonal to the article, because it requires long platforms.)
[1] https://en.wikipedia.org/wiki/T_(SEPTA_Metro)
Indeed, the Victoria line in London manages 36 TPH and we've not bothered beating it since. It's much easier to run 26-30TPH with slightly more carriages.
> the Victoria line in London manages 36 TPH and we've not bothered beating it since
That was a world record for a line following modern safety standards, set less than 10 years ago. It's hardly a case of "not bothered", it's just hard.
90 seconds is very possible in new-build lines which is what the author is talking about. You can buy a turnkey Innovia (e.g. Vancouver Skytrain) or AnsaldoBreda (e.g Copenhagen) that does this out of the box. Retrofitting 90s operation is basically impossible but not the point of this exercise.
Yes, they are assuming a best-case scenario. Driverless systems are very expensive for reasons that have little to do with the cost of the driverless trains, if you're not going to consider those variables this kind of armchair speculation is a waste of everyone's time.
They aren't though? If you're building a new line, fully driverless is pretty much the default these days, especially if the line is fully underground or elevated.
What is incredibly expensive, though, is retrofitting a line designed for manual operation to run automatically instead.
Well, a lot of systems exist that were initially designed for automatic operation but still end up becoming operated manually or partially manually due to safety concerns or politics. Washington DC Metro and BART are the two big systems I can think of that had this issue.
Both examples of Great Society metros that were on the bleeding edge of what was possible in the early 70s. Automatic train control advanced rapidly, with both Vancouver SkyTrain and London Docklands Light Rail being built in the 80s and operating driverless for their entire existence.
DC Metro just recently re-enabled full automatic train operation across all the lines in June.
They took "30-40 trains per hour" out of thin air and exercise was to calculate whether it is even possible to have more frequent shorter trains.
I don’t think anybody has tapped into the forbidden magic trick of having CBTC broadcast position and velocity instead of position alone. For vehicle ACC at least, there is a safe region of velocity and follow distance where a following train can plan to enter the space where the lead train currently occupies.
I wonder if it's possible to run trains at higher speeds closer to each other using fixed brakes embedded near the tracks, similarly to how roller coasters often have mid-course brake runs that are only activated in emergencies when the train ahead unexpectedly slows or stops.
What works for a strapped in amusement park rider doesn’t work for the standing commuter holding a cup of coffee.
Trains have the capability to accelerate and decelerate faster, we mostly don’t do so for comfort and safety reasons.
Roller coasters accelerate and brake much harder, which is fun for the restrained passengers but not for commuters.
Signaling systems used on automated trains know the position, speed and capabilities of every train. Keeping a safe distance behind isn't a problem.
We're at the point where we could easily fit so large a fraction of the rail length covered/overshadowed by the train with https://en.wikipedia.org/wiki/Track_brake that we could pull around 4 G deceleration if we cover the bottom in that brake chains (chain strong; chain flexy enough to just wiggle over humps in the track).
I think this observation is undervalued:
> Wait times are the second-most underrated component in making metro systems effectively faster (right after street to platform time).
Street to platform time made using public transit annoying in several Asian capitals. Wait times are the main reason why I often hate traveling with public transit even in a city with one of the best public transit systems - if you aren't planning your life around the transit schedule, the wait time is essentially an unpredictable part of your travel time (and if you do plan around it, it's one more annoying thing to deal with).
If you leave your doctor's office, and you have a 10 minute train home that goes every 30 minutes, then you really have a 10-40 minute train home - so for practical purposes, you essentially have a 40 minute train. Once unreliability or delays become frequent enough to start being a factor to consider, this could easily turn it into a 70 minute train.
Another big factor is the time between the actual start/end of the trip and the nearest station. Even with near-zero street-to-platform time (e.g. busses/trams) and reliable, reasonably frequent public transit, once you add it all up, a bicycle often ends up being faster than even excellent public transit.
Munich is a counter example: It has many lines passing through (almost) 11 stations. They run at maximum speed of 40 trains per hour. It is a traditional block signal system with each block being shorter than a train - so they can run trains packed into tighter space. Each train opens left and right doors simultaneously so people can board and exit at the same time. Boarding still takes time. It is overcrowded at rushhour and brakes down regularily (a train being at a station for too long blocks all proceeding trains). And at Oktoberfest time, the stations are soo crowded that boarding takes longer.
Munich is planning on building a second subway route. It just does not have the money nor the space to build one. There has been discussion on building a second tunnel below the first, or on enabling the common train system for overflow by suburban trains -- by installing more signals to run more tightly packed.
The second route is currently being built in Munich [0], with work started in 2017. I recently watched a youtube video by The B1M about rail projects in Germany that included a long section about the currently ongoing works in Munich [1] that gives a good visual overview.
[0] https://db-engineering-consulting.com/en/projects/munichs-se...
[1] https://www.youtube.com/watch?v=bPDQdnT-RaY
I feel like this is one of those articles that claims some clever idea on paper but without experience of how this would actually work IRL but IDK if the OP has more experience than me so I will assume the best.
Others have already pointed out some of the practical things that would limit what you can achieve with shorter trains like minimum headway between trains and the congestion that would occur after a delay where you would expect people to wait for maybe 10 short trains to arrive and depart before you could get on.
There are other problems. The cost of the smaller trains means if e.g. 2 carriages each, then every other car is a driving vehicle with motors and control equipment. On longer trains, this could be 1 in 3 or 1 in 4. Each of these not only requires regular maintenance (so that's doubled the maintenance requirements) but also creates massive congestion issues in maintenance yards. Commonly, 1 or 2 full trains fit in each siding so getting most trains out if e.g. one is broken down is usually easy enough. Imagine having to move 3 or 4 separate smaller trains out of the way, they are not automated in the yards.
Most people would be very unhappy knowing that they might be alone on a train, which is a main reason why operators are not quick to get rid of all staff. But currently, a single driver and conductor is close by for, maybe, 8 carriages. This would double if you needed a single attendent on each 2 carriage train.
The signalling is very heavily designed around traditional trains with its delay after passing a signal. 4 x 2 carriage trains would utilise more signalling capacity/time than 1 x 8 carriage train. If these were all coming from the same location and needed to return, that would also need a lot more platforms so that the following trains don't block the first trains in terminal platforms. This is already a major problem at most UK terminal stations so that is largely unsurmoutable.
I also heavily question the idea that station cost is largely dependent on platform length. On most surface stations, platforms are relatively easy to construct and whether they are 4 carriages or 12 carriages long still require a station building or 2, some ticket machines and CCTV etc. For elevated railways that is more likely to be true maybe.
So yeah, like someone else said, we are unlikely to come up with ideas that 1000 other engineers haven't already asked, the easier problems to solve are around planning, design, legal rights for infrastructure projects etc. since these tend to eat up sometimes decades and billions of dollars.
Of course coming from the UK there is nothing that strikes horror into my heart more than being at a crowded platform waiting for a late train and it pulling up with half or quarter the carriages that you expected. Feels like a luxury to imagine a system where you’d get to tweak these variables until things work rather than trains being a force of nature.
Something I've been thinking about lately is short trains but long platforms. Basically, you split the length of the trains in half and then split the platform into two boarding areas. In this way trains can be scheduled even closer together than the the 3-min physical limit of of signalling because the one coming in behind doesn't need to wait for the one ahead to leave the station first. Its therefore possible to schedule several different services on the same two-track system such that they all skip a large fraction of stops (and thus run faster), but every station is still reachable from every other without transferring.
A simple example would be 3 services on the same line that follow a repeating pattern every 3 stations. ==[A]==[B]==[C]==[A]==[B]==[C]==. The service (AB) stops on the stations labelled [A] and [B] (skipping C). The service (AC) stops on the stations labelled [A] and [C] (skipping B). The service labelled (BC) stops on the stations labelled [B] and [C] (skipping A). In this manner, all three services skip over 33% of the stops on the line, but no matter what your origin and destination, it is always possible to travel from an [A] station to a [B] or [C] station (or another [A] station), and likewise from a [B] or [C] station.
To the extent I've worked out the logistics of this, if you allow for trains to catch up but not pass each other at the platforms, you can push this idea as far as only stopping at 2-in-5 stations without sacrificing headways or capacity.
Just a weird thing thats been taking my attention lately.
In a lot of train systems this exists in the form of fast / stop trains, the fast trains only do the bigger train stations, the stop trains stop at every station, servicing smaller stops.
As for short trains on long platforms, this is pretty common in NL where the bigger train stations can support both very long international trains and shorter local trains on the same platform; a train can switch to a center track halfway on the platform.
I don't think it would really work for a subway system; people expect it to be hop on, hop off. In some places the stops (or people's final destinations) are so close together they can choose to get on/off earlier/later, but this system makes that less viable. You'd have more people shuffling through train stations trying to figure out which train to get or whether they need to wait for the next one, also putting extra load on staff for confused not-locals. And finally, you'd need extra rails or tunnels so that a train can pass another.
How would that help? 3 minutes is the minimum separation distance, if the trains have different stopping patterns then that just means they'll be further apart for part of their journey. If you have to stay 3 minutes behind the train in front, you might as well stop at all the same stations that it does, you can only save time if you were further behind to start with, so you can't increase throughput by skipping stops.
Simplifying a bit, its because the train behind can be scheduled 3 min after the train ahead has pulled in rather than 3 min after the train ahead pulled out. Put another way, the safe stopping distance to maintain (while at speed) would be measured from the half way point of the platform rather than the start of the platform.
This lets you schedule them much closer together than the conventional 3 min while still being safe.
> its because the train behind can be scheduled 3 min after the train ahead has pulled in rather than 3 min after the train ahead pulled out.
Why? If the minimum is 3 min then it's 3 min (at least with a modern moving-block type setup). If it's safe to run them 2 min apart it's (generally) safe to run them 2 min apart the whole time.
I feel as if the time spent by each passenger walking to the right boarding area could easily surpass the dwell time of an extra stop or two.
Consider a metro system with trains 70 m long. With 10 m of space between the two boarding areas, that means the length between both sides of the station is 150 m. If the entrance to the platform is in the center, the walk to the middle of each boarding area is 45 m, taking about 30 seconds. If the entrance is at the end, that becomes 35 m or 115 m (taking about 20 to 90 seconds to walk). I think those figures are comparable to the dwell time of a typical metro system.
I do think it's a very interesting idea though! I think it'd work better for longer trains over longer distances, where the time spent accelerating and braking is often greater, but unfortunately few places are even considering anything shorter than 15 minute headways for such rail services.
Admittedly my calculations did not take walking-on-platform time into account, but what I have been assuming (based on figures I've looked up) is that each stop adds about 60 seconds to the journey time (30 seconds for dwell + 15 on either end for getting up to / down from cruise speed). I've also been assuming that the inter-station no-slowing-down time is 2 min.
So in a 2-of-5 stopping pattern you'd save 3 min every 5 stops, but depending on when arrive at the station you will sometimes get unlucky and just miss your train, in which case you'll have to wait an additional interval than you normally would for the next one (costing you 3 min). So for very short trips (under 3 stops) it actually makes travel time a bit worse since there's very few stops you can skip over in such cases. But for more median trips there is a saving, and for the longer trips it saves well into 2-digit minutes.
In your example I think in the case with the entrance at the middle of the platform there wouldn't be any real effect, because splitting the platform also in the middle doesn't marginally change how quickly you can get to the nearest open door on the train you want. There's no real need to get to the center of either boarding area. In the case of platform at the end of the station, I can accept that adds about 40 m of walking distance that wasn't there before (at least for some people), and that translates into an extra 20ish seconds. Less than that if you do the rational thing of walking briskly when you see you're about to miss your train.
So you're right that the platform split adds some time which isn't completely negligible, and depending on what fraction of the next n stops you want to skip it comes at a penalty of longer wait times for the correct train, but both of these are fixed upfront costs whereas the dividend accrues linearly the longer your on the train.
The main cost of construction is station length, so making longer platforms with shorter trains is the worst of both worlds.
This is how it already works in Europe (at least in Austria and Germany, but I assume elsewhere in Europe as well).
You will also find long trains that split in half mid-journey, so you need to make sure you get in the right car or you'll go to the wrong place.
Edit: I guess it's not exactly what you're saying, in Europe you will find platforms split into several sections with multiple trains to board, but they'll be for different lines with different destinations.
yeah, what I have in mind is a variation / generalization of skip-stop.
https://en.wikipedia.org/wiki/Skip-stop
The author spends a lot of words talking about short trains and Jersey City, but didn't once mention the Hudson Bergen Light Rail which was at least built in recent memory? I mean other than driverless operation it seems to check all the boxes. And in that light, I really fail to see the novelty in this argument; it's basically the multi-decade-old argument that building light rails is cheaper and better than real metro or heavy rail.
there is nothing new about trains - we need to stop looking for innovation and just build them with small incremental improvements. The only useful innovation since 1920 is full automation (though I'm going to call high speed rail incremental since it is mostly a lot of small improvements on the way - this is debatable). Even full automation was a lot of incremental improvements.
That said, full automation is a major game changer because it enables short trains with high frequency which you would otherwise struggle to afford. Don't build light rail, build light metro which is a small cost more (build a metro with light rail) but now you can have full automation.
I also thought this omission was conspicuous. The author has some reasonable points, but the sections on NYC and NJ felt like political wish (spite?) casting: just about the only state in the US that struggles more to build mass transit than NY is NJ. The HBLR is a rare survivor in an otherwise very crowded graveyard of NJ mass transit projects.
Loebner (of the prize fame) patented the idea of a rollercoaster tube system. Stations on the surface, going underground and up to the next station. Saves power and reduces the curb to platform time. Just thought I'd put that out there...
But then you'd need stations and part of the rails on the surface, taking up valuable real estate. Versus a small entrance building. Not sure how or how much it would save power either.
Some train lines are designed like this although obviously much more gradually like the Victoria Line in London. In practice it’s pretty negligible.
Note: This only seems to apply to driverless trains.
Depending on the system in questoin, this might be impractical or impossibly dangerous.
I don't think there is any danger to running more frequent longer trains. Ultimately you are constrained by the signalling system; nobody is suggesting "just disable the tripcocks and plow through red signals". Modern systems use moving block cab signals, so are set up to succeed with high frequency. (But there are other problems, like terminal capacity, that can limit frequency. The MTA in NYC spent a ton of money giving the L CBTC to run 40+ tph... but the terminal at 8th Ave can't turn that many trains. Until that's fixed, the L will always be overcrowded.)
You can see whether the problem is being cheap or if it's actually a capacity issue. If weekend service sucks but peak hour service is good, then it's just being cheap. If rush hour can't handle passenger volumes, then you need a signal system / automation upgrade. (Or a parallel line!)
As a New Yorker, I'm very jealous of Vancouver's SkyTrain system. ("But NYC has the best metro in North America!!" Maybe...) The NYC subway has a lot of peak hour capacity. I hate traveling at peak hours. So that means I'm always standing in stations waiting 10 minutes for the next train. If I lived in Vancouver, then that would be 3 minutes. Sounds good to me!
I also agree with the author in that I'm not sure what elevated trains did to hurt people. I lived in Chicago next to the L for years. It never bothered me. It's nice to see out the window and look at something while you're in transit. And it's cheaper than building things underground. NYC apparently got rid of its elevated railways because of snow, so that's something to watch out for. But Chicago gets more snow and it does OK. (Having commuted on both systems in the snow, it's a mixed bag. Chicago doesn't shut down, but it's slow as people remember how to deal with snow. NYC can run on snow-free underground tracks, but sometimes the governor is like "fuck it, I'm cancelling all the trains anyway" and then you're just stuck.)
SkyTrain vs Seattle Link Light Rail is a fascinating contrast.
SkyTrain works because of a virtuous cycle of attributes: Full grade separation enables automation. Automation enables many trains per hour. Many trains per hour with short trains still has tons of capacity. Short trains means lower costs for stations, which as the article notes is a huge portion of rapid transit costs. Lower cost means building more transit for the same budget, so more transit gets built. More transit with great headways results in transit being the mode of choice. Take any one of these elements out and you can still have a functioning transit system, but the magic is missing.
Link light rail is so close to full grade separation but not quite there, so headways are limited by the grade crossing. With longer headways, bigger trains are needed to serve the same capacity. Bigger trains mean big stations and beefier, more expensive viaducts. Big stations are expensive.
Link is gaining ridership and offering great service, but it's hard not to think if they had learned the full lessons from nearby Vancouver it would be even better (and cheaper).
> I also agree with the author in that I'm not sure what elevated trains did to hurt people.
They're horrifically ugly for pedestrians and city life generally. If you've been around the elevated subway tracks in Brooklyn, for example, they're not pleasant to be around. They block out the sun, they're incredibly noisy, they make the street claustrophobic, they definitely become streets to avoid unless necessary.
Yes, they have a nice view if you're a passenger. But they make the city much, much worse for everyone below them.
And yet you don't hear the same complaints about the elevated metros in Paris. Why is that and what can we learn from it?
Oh yes. In Manhattan there were plenty of elevated lines that were dismantled because the people thought that they were too noisy and should be replaced with subways. The Second Avenue had an elevated train that was supposed to be replaced by a Second Avenue Subway, but the latter is only partially complete.
The elevated steel structures of the NYC subway and Chicago El have nothing in common with modern elevated rail. Modern concrete guideways are small and quiet.
Melbourne is eliminating grade crossings with new guideways and creating linear park space underneath as they go.
Off-peak the wait for trains seems like forever in NYC.
> I also agree with the author in that I'm not sure what elevated trains did to hurt people.
You need to either build them in right at the start of a new development or you gotta demolish a lot of housing - similarly to what was done in a lot of US cities when the highways were built [1].
[1] https://www.reuters.com/world/us/us-freeways-flattened-black...
> I also agree with the author in that I'm not sure what elevated trains did to hurt people.
I've only seen them in Hamburg. They are generally an eye-sore. And the area underneath them is somewhat unusable (like any area under a bridge): you can't really build anything there. So it's an eyesore above an eyesore.
There are plenty driverless trains in operations. Some have been running for decades. For example Toulouse in France has a metro without drivers since 1993. I was there a decade or so ago and sat in the front of the train on a bench in the front of the train staring out into the tunnel. Because there isn't a driver compartment. Really cool. They have some fences on the platform that align with the train doors for safety. The train lines up, people get in/out and it drives to the next station. Some airports have similar systems. This stuff has been possible for quite some time.
These days, you should be designing for autonomous operation for new infrastructure. Much easier when you design from the ground up. Not doing that could be an expensive mistake.
I mean this is talking about construction of brand new lines, and in the Western world if you are building a brand new, totally separated line then automated is the no-brainer solution given high Western labor costs.
There's the analysis that, in the long run, operators are expensive which is an argument for automation or long trains.
Automation with short trains is similar price to long trains, but the short trains will run a lot more often and that will attract riders who have a choice of driving or not. If they miss their bus/train or have a long wait for their bus/train they will fix that by driving. However if they try transit and service is frequent they will realize that transit works just fine and so they will choose to not drive even though they can.
Frequency is freedom.
Nothing feels slower than standing still. Sitting in congested traffic sucks, and so does loitering on a train platform or a bus stop.
When the vehicle arrives so quickly you don't even consider the timetable or care if you just miss a train transit is an easy choice.
Is it written in stone that a train must fit entirely into a station so that all doors face the platform and can be open simultaneously?
If we think of the station as the head of a Turing machine ...
It's not written in stone, but if you don't, people will be moving through the train and pushing to get out sooner. Public transit is a test of patience and a study in human herd behaviour.
> Is it written in stone that a train must fit entirely into a station so that all doors face the platform and can be open simultaneously?
When you're building high capacity transit for dense cities, yes. You could stop the train twice in the same station, sure, but at that point you have to stop for twice as long (probably a little longer than that as your riders will get confused), so your train takes ~twice as long to get anywhere and can therefore carry ~half as many people.
It is really a safety and dwell time thing.
The moment you have only some cars platforming, then people need to make sure they are in the right car, and if, say, a slow-walking elderly person is in the wrong car, then her getting into the right one to get off wastes a lot of time.
it's all about capacity requirement. If the capacity demand is high, you might want to build really long trains and run them as frequently as possible (e.g. Istanbul Marmaray)
Why are tech dudes so hung up on homelessness? Also, the reference to it was so callous and would seem to reveal a complete lack of empathy: NYC has too many homeless people; let's build a metro in Jersey City in order to make Jersey City ... more of a thing and not even attempt to address the "problem" in any substantive way.
It's also a feat of mental gymnastics to put European infrastructure on a pedestal while ranting about NY's taxes and, more broadly, the US' difficulties building infrastructure.
Incredibile that noise, visual impact, potential disruptions to residents and property devaluing are not even mentioned in the article.
Compared to car traffic, rail is a lot nicer. Putting it in place is indeed disruptive; just like any kind of infrastructure work. Once you have it, property values tend to go up, not down due to better transport options.
Not if the railway obstructs your view from the windows.
jersey and short trains makes me think of the newark air train, easily the worst train in the US
Good news is that it’s being rebuilt/replaced!
In the US you can't do it, because the unions lobby to have two people per train and the people really like unions.
EDIT: Listen, you can downvote me but it's true https://www.etany.org/statements/impeding-progress-costing-r...
"Facts don't care about your feelings"
New York MTA is not representative of the whole US. DC Metro for example has one driver per train. AirTrain JFK is automated with no driver.
> Small Train is Good Train
In a few years I think we'll recognize that self-driving vans (in a few different sizes) are the best trains: cheaper than trains (and therefore lower environmental impact), completely flexible routing, and you can even let them use dedicated right of way if you want to increase capacity.
We can call them a bus...
Most suburbs are dense enough to have demand for full sized buses if service is good. The cost of a bus means that cities don't give them good service, but automated bus drivers would reduce the costs enough that they could run good service and this in turn will get so many people to use the bus instead of driving that the van could not work.
For rural areas a van might make sense, though you quickly get to a frequent van is less efficient than just owning your own van.
Yep, but I think automated bus drivers change the math. A standard-ish city bus is $1M and seats 50 (though they're rarely full). You could definitely get 5 vans that would seat 6 for $1M. Absolute seating capacity is lower, but total throughput could be greater because of the extra flexibility.
That doesn't work. If you run frequent service more people will use it and so you still need the big bus.
Smaller vehicles allow more dynamic dispatch. SF buses are low quality transport because they have to stop every block to allow for an elderly local population. With vans, you can put more of them on the road and dynamic dispatch allows them to skip stops for non-loading.
This structure allows for greater QoS through the system. Almost any sufficiently dense place without regulation limiting it approaches a mix of larger buses on fixed routes with smaller vehicles on slightly less fixed routes.
SF Muni has a 13% absence rate. Without the driver we can have more vehicles, more often, and on-time every time. Once we can do that, we can vary the size of the vehicles to cover different routes and to allow for QoS.
That is a horrible idea and shows how little you care or think about bus riders. Bus riders need predictable. If the but has dynamic dispatach you can't trust it will get you there on time. We need predictable routes with minimal variance so everyone gets predictable. Good qos is predictable.
I don't think you read what I said. It's about combining fixed routes with flexible. But also this is clearly a religious subject for you, so perhaps it's better to call an end to the discussion.
> self-driving vans (in a few different sizes) are the best trains
Until you actually do the basic middle-school math of calculating capacity. Both of vans, and of the roads
https://en.wikipedia.org/wiki/Personal_rapid_transit
seems to be the worst of all worlds but never quite dies
> cheaper than trains (and therefore lower environmental impact)
How does that work? For the same amount of capacity, vans are not and probably never will be cheaper. Steel wheels on rails, with massive capacity, is just drastically more efficient, even with 0 driver costs. You'll still have much more maintenance (the tires, breaks, road) to do with a much higher number of vehicles.
I've yet to see a convincing argument that trains are cheaper than busses (especially when you consider that most of a bus's route (in the USA) would be on "free" roads).
Trains can certainly HOLD more people than a bus, and I hate buses with a passion normally reserved for religious arguments, and trains are Choo-choo, but they are expensive as all hell.
If they weren't why would BRT exist at all? https://www.youtube.com/watch?v=3q-UHd9tFNk
If the bus is using "free" roads, then it's forced to compete for space with general traffic and likely to perform far worse than BRT or trains that don't have to do this. Worse performance/speed/frequency => lower ridership => worse profitability => calls to cancel the "wasteful" bus etc.
The only way out IMO is that we have to stop ripping off the public by giving away unlimited road space for free.
> I've yet to see a convincing argument that trains are cheaper than busses (especially when you consider that most of a bus's route (in the USA) would be on "free" roads).
For a given capacity requirement, in a dense city, they're cheaper. The biggest costs of an urban train line are 1) building stations on expensive land 2) driver salaries, and buses are worse on both aspects; you need much more station space to load/unload the same number of people from buses than from trains, and buses carry far fewer passengers per driver.
> If they weren't why would BRT exist at all?
As far as I can tell BRT is a spook, a way for the road lobby to stop cities building rail. Has it ever actually worked out well for passengers?
Bus lifespan is 15-20 years max and needs tons of maintenance during that time. Trains last 40 years and go 100,000 miles+ between failures.
Trains are a bigger upfront investment, but are cheaper in the long run, especially once capacity is factored in. You need a lot of busses to equal moderate sized trains.
Busses have their place, but not as the backbone for rapid transit in even moderate sized urban areas.
BRT trades CAPX for OPEX. In Latin America where BRT is hugely successful capital is expensive and labour is cheap, so hiring a ton of drivers is easy. In high labour costs markets like the US, Canada, and Europe BRT falls apart. It's often all transit agencies think they can get funding and support for so it's pushed, but it's way too easy to cut back BRT attributes like signal priority, dedicated lanes, and all door boarding to end up with just a bus with a fancy livery.
I'm sure it differs by metro area, but somehow "dollar vans" (https://en.wikipedia.org/wiki/Dollar_vans_in_the_New_York_me...) can be profitable in NYC, but most US public transit systems are huge money losers.
It's quite easy to make a profit from a bus system that operates in peak commuter hours on peak commuter routes. It's virtually impossible to make a profit from one that has a public service obligation.
The key benefit of BRT is that they have a dedicated right-of-way without conflicts with other traffic just like train tracks with full grade separation. So to do that, BRT suddenly no longer has free roads. You now need dedicated BRT-only roads.
This will depend on density and what's already built. An extreme case: it wouldn't make sense to replace a large, rural school district's bus fleet with trains.
All trains, tracks, and stations are specially designed and built, which makes them very expensive. There is no mass-produced off-the-shelf solution like with cars and roads.
Trains are unbeatable for inland freight between limited destinations, but don't make much sense for current day commuting or traffic patterns.
This is not really true. There are absolutely things in the rail system that are as “mass produced” as roads are. Railway platforms for example are a highly standardised form that has many other applications (loading and inspection bays, walkways etc.), trains are actually not only mass produced (e.g. by Bombardier) but are actually leased by their operators in Europe; there are five or six, I think, main ROSCOs —- rolling stock companies —- in the UK for example.
There is a notable exception that might distort techie perception on this issue: BART. It implements many of its own standards, even down to track gauge. But it is absolutely an outlier (standardised track gauge, ironically, being the USA’s main contribution to the development of the railways, which it was otherwise late to).
Almost everywhere else has rather interchangeable infrastructure and a lot of trans-national businesses.
Wasn't standard gauge first standardized in the UK? Wikipedia says 1846.
https://en.wikipedia.org/wiki/Standard-gauge_railway
> but are actually leased by their operators in Europe; there are five or six, I think, main ROSCOs —- rolling stock companies —- in the UK for example.
Nah, this is a UK absurdity because they UK decided to privatise their railways in the worst possible way - every single part (rail infrastructure, operations, rolling stock) was privatised in a local monopoly manner. The rolling stock owners could lease to multiple different operators, so there was some limited competition on that front (probably eviscerated by the need for the ROSCOs to have a profit margin, on top of the fact that there were 10 of them, which meant reduced economies of scale both at acquiring but also maintaining those trains).
They're currently trying to nationalise some parts, after already nationalising the infrastructure (because people died due to bad maintenance due to misaligned incentives - maintenance doesn't bring profits).
But other than that, rolling stock leasing mostly exists in freight.
https://en.wikipedia.org/wiki/Rolling_stock_company
> trains are actually not only mass produced (e.g. by Bombardier)
But yes, trains of all types are mass produced by companies such as Alstom (which were already massive and also bought Bomboardier's train arm), Siemens, Stadler, etc. They can be customised (size, features, etc.), but e.g. the Alstom Metropolis line of metro trains can be found all over the world.
There are off the shelf trains, tracks, and stations already. It's one of the key ways many european and asian operators deliver tons of transit for the dollar.