I encountered Latin American cable cars in La Paz, where they were necessary as the only viable mass transit option - the main suburb El Alto is up a very steep hill, ruling out trains or subways, and the single road is already a traffic jam of small buses.
Conversely the "Emirates air line" in London is a boondoggle, not linking useful places and surrounded by tube and bus lines.
It's about ten or twenty years too early to establish the success of the Emirates Air Line. In London it's necessary to build infrastructure well before the demand appears because otherwise it's too late to thread it through high density development.
At the south end, there's an enormous new housing development being built next to the cable car stop. The southern station is also next to the terminus for the increasingly-popular river boat service. The boat service has taken at least 20 years (and several operator bankruptcies) to get (re)established and what was once a tourist-only route is now picking up more commuters as the frequency improves.
At the northern end, the stop is close to the Excel and Custom House station, where there will be a link to Crossrail.
As you mention there are existing tube and rail stations in the area but they are heavily overloaded. The DLR is packed when there's a show at the Excel, and the Jubilee line is so full at rush hour you often have to wait for several trains.
The cable car also adds a little bit more resilience to the network, allowing options when one of few eastern rail river crossings is running badly. I've taken the cable car plus the boat to get back to Westminster from the Excel when the DLR was closed by an accident.
Once the sponsorship runs out (more than half the cost was paid for by Emirates) and it becomes fully in TfL's control - we might see if it becomes a useful, practical, transport link rather than just an occasionally useful tourist attraction.
Sorry, I only provided subway speed as a comparison of speed. Getting people out of their cars and onto mass transit isn’t as much of problem in Manhattan.
The problem with subway speed is not top speed, it's maximum acceleration. There is a maximum acceleration (and deceleration) above which the metro is uncomfortable or even dangerous to its users, some of which are going to be standing.
Since the speed at stations has to be zero, this automatically limits your top speed unless you make the stop farther apart, which then comes with other downsides.
A 60 mph metro doesn't really make sense so you can't compare that to the speed of NYC subways, however in Paris there are already two separate systems (completely integrated though): the metro with short stops and the RER with longer sections.
The RER already goes to 100 km/h within Paris, it moves about 3 million passengers per day, on regular rails (the RER A line is the rail line with the most traffic in Europe).
I don't know what are express subway stops in NYC and if they have a higher top speed than regular subway cars, but I doubt it unless they have separate tracks - they might be faster by skipping stations but that's unrelated to the topic.
I'm not saying it doesn't exist anywhere outside Paris anyway, just that it already exists outside Beijing. I'd expect London to have a similar system, too.
https://link.springer.com/article/10.1007/s40864-015-0012-y says about 1.5 m/s² is the maximum acceptable acceleration rate for passengers. My local metro in Lille uses 1.3 m/s² and I find it barely acceptable. But that is only acceptable anyway over a short time, and for a trip under continuous acceleration/deceleration it should stay under at most 0.5 m/s². I'll let you do the math for how many seconds you can gain on a 500 m stretch between metro stations.
Also, RER or TGV lines are really just as smooth as the maglev I have used in Incheon. Rail is very smooth and quiet on modern continuous welded rail. On TGVs on dedicated lines you usually don't notice when the train starts.
> with a maximum designed train speed of 100 km per hour
I would be curious to read about the costs of maglev vs traditional rail for this speed range. Does it really make sense to use that tech for low speed?
In contrast, Santa Clara County's VTA gets a farebox return of about 12% of operating costs... and that includes nothing toward capital equipment or debt service.
That's the joke to me, people complain about how we are subsidizing buses and train service- "The buses STILL don't make a profit!"- but when have roads for cars ever turned a profit?
Which is why we should look at more private funding, and a free market competition. Levy a pollution tax and a congestion tax, increasing both to keep traffic flowing smoothly 24x7. This will naturally incent use of higher-capacity vehicles like buses or 18-person vans in peak hours. I don't believe a centrally-planned bureaucracy can decide which capacity vehicle should run in which route at what times and on what days at what frequency, certainly not in India where the bureaucracy is incompetent.
For many years fuel duty was set at a high level to discourage car use. Since then it has become a large amount of money that the government doesn't want to lose. But it is a bit ironic how it is treated as a source of revenue for road building in the public consciousness. It just doesn't seem to work very well at discouraging driving. People include fuel tax in a basket of other costs and factors they have to contend with.
When talking about cost recovery of transportation systems, we absolutely should talk about the positive and negative externalities of those systems.
Transit systems and roads for private vehicles provide massive benefits to society in terms of mobility. Transit systems have different (i.e. better) scaling characteristics when very many people require mobility. Also, the shared marginal cost characteristics make it a better fit for offering lifeline service to the poor.
In terms of negative externalities, society’s private vehicle fleet is a major source of polution, often the major source of polution proximate to where humans live. And then there’s the > 10x 9/11s worth of traffic fatalities that we in the United States endure each year.
So yes, we absolutely should consider the mobility benefits of roads and transit systems in context of cost recovery. As someone with a background in transportation planning, I’m inclined to think that the United States is a little too obsessed with cost recovery for transit systems, and is pretty blind to cost recovery for the public infrastructure that serves our private vehicle fleet.
I would look at integrated economic growth as opposed to the productivity. There are a lot of things that are ultimately cost centers, but promote economic growth. When a high economic growth is integrated over let's say 100 years you get a superpower.
Here's some schematics of Bogotá's mentioned cable car.[0] Bogotá desperately needs solutions to the cities car crowding. They've tried a lot of innovative things: closing major roads on Sunday only allow bikes and pedestrians, limiting cars in the city by license plate number. The traffic is still terrible.
Also of note, taxi associations in Bogotá have been facing off against Uber, sometimes violently.
Those innovations sound like you could be talking about São Paulo as well (they've done all those things). One of the proposals I once heard from a São Paulo city planner was for more people to telecommute. If more companies allow for remote work, the streets don't need to be (as) congested. But I'm skeptical about the long-term success of such a move.
What would work a lot better, with the current set-up, is a massive carpooling scheme, since SP transit stats show most automobile trips are single-occupant (IIRC). What would work even better than that is another city-planning 'trick' - making as many neighborhoods as self-sufficient as possible (work/shop/commune near where you already live).
I encountered Latin American cable cars in La Paz, where they were necessary as the only viable mass transit option - the main suburb El Alto is up a very steep hill, ruling out trains or subways, and the single road is already a traffic jam of small buses.
Conversely the "Emirates air line" in London is a boondoggle, not linking useful places and surrounded by tube and bus lines.