If parking lots be used, why not use existing parking lots?
While I would very much want to see an HSR station situated beneath the main terminal of every main hub airport ... O'Hare, Midway, Pittsburgh from where I live in Northeast Ohio ... that is to allow people to avoid the nightmare of the airport parking lot ... so, for instance, if Pittsburg Airport has a station, that would in in addition to the two outer suburban and the urban station.
The pedestrian 'market' of a high-speed station is negligible.
It is around the high speed station alone ... though bear in mind that UScentrism note, this is directed generally at both actual HSR and "Express Rail", defined loosely as everything between the US legislative high speed definition and real HSR ... its the pedestrian market around each dedicated-corridor transport system that integrates directly to the HSR station that allows it to gain noticable traction.
Here I would have liked if dKos readers had been given an idea of the differences between the various local rail systems, though that may warrant a whole new diary.
Aerobus I am sceptical of this. In particular, I am sceptical about low infrastructure costs. The capacity, especially if single-track, is limited. If running above highways, stations can't be integrated with the city. If running in a city, unlike when above an already noisy highway, noise emissions can be a problem (you can't build shielding walls). And from what I know about railway catenaries, I really wonder how they manage vertical swings and traverses of attachment points at pylons.
I am sceptical of this. In particular, I am sceptical about low infrastructure costs. The capacity, especially if single-track, is limited. If running above highways, stations can't be integrated with the city. If running in a city, unlike when above an already noisy highway, noise emissions can be a problem (you can't build shielding walls). And from what I know about railway catenaries, I really wonder how they manage vertical swings and traverses of attachment points at pylons.
All Aerobus is double tracked, with the headways determined basically by the section length, with one vehicle operating per section per direction. They have the same capacity as a light rail or monorail system ... roughly a quarter the capacity of a heavy rail system, which is a very good fit for a trunk system in most of outer-suburban US. Its also a good complement to a conventional 120kph heavy rail line.
I don't understand the question of noise emissions ... what noise emissions? Electric motors driving steel wheel on aluminium track in an enclosed nacelle does not generate a lot of external noise. The first generation of the system, which ran directly on suspension cable, would have been noiser, but that was
At the pylons the track is fixed to the pylon rather than resting on the suspension cable.
This is not a recent technology, its a technology that ran into the lack of funding for public transport infrastructure in the US, and has been recently revived to serve the new demand in China. It was brought from its early trial versions in Switzerland, Germany and Canada and brought to full scale development to win a place as one of the three finalists in the US DoT 1992 $30m award for development of suspended transport systems ... but the award was never actually funded.
To my mind, the highest priority in running over highways is getting across the damned thing, but note that in the US, most newly established large office parks and employment centers are located in a ring around the city, accessed via the Interstate Highway (so-called) "bypass", or "outer loop". So an ability to easily cut back and forth across the highway can be very handy. I've been accused of being a Marxist, yet while Harpo's my favourite, it's Groucho I'm always quoting. Odd, that.
This depends on the speed of the system, but aerodynamic noise can be significant. The cable itself may radiate noise, too.
At higher speeds (say 30 mph) That will lead to 'bumps' when the train is changing from cable to fixed way, exposing the cables to sharp changes in stress, and the train will continually go up and down.
Overall, I don't want to be too much of a sceptic, let's see if this technology stands the test of actual use, in China or elsewhere. *Lunatic*, n. One whose delusions are out of fashion.
It seems that some of this is a FAQ, since on their site they say:
C) Pylons The Pylons support the Suspension Cables as the Suspension Cable is laid into the top saddle with some freedom of movement on rollers. Conversely, the lower saddles on the pylons are fundamentally a short segment of a fixed rail to hold down the cables which support the rails between pylons. The rail supporting cables are pre-loaded by the vertical hanger cables, which in the absence of a vehicle, keep the cable supported rail in an arch above the horizontal. The rail supporting cables remain uninterrupted at the saddles as they are placed underneath the fixed rail segment similarly to the manner described at the stations. The vehicles make a smooth transition through the tapered ends of these short segments of fixed rail on each side. The short fixed rail segments are pivoted at the center to adjust to asymmetrical loading, as when there is a vehicle on one side of the pylon and none on the other.
The Pylons support the Suspension Cables as the Suspension Cable is laid into the top saddle with some freedom of movement on rollers.
Conversely, the lower saddles on the pylons are fundamentally a short segment of a fixed rail to hold down the cables which support the rails between pylons. The rail supporting cables are pre-loaded by the vertical hanger cables, which in the absence of a vehicle, keep the cable supported rail in an arch above the horizontal. The rail supporting cables remain uninterrupted at the saddles as they are placed underneath the fixed rail segment similarly to the manner described at the stations. The vehicles make a smooth transition through the tapered ends of these short segments of fixed rail on each side. The short fixed rail segments are pivoted at the center to adjust to asymmetrical loading, as when there is a vehicle on one side of the pylon and none on the other.
I presume that all means something to someone who knows something about using suspension cable.
As you can see from the picture, there is a main suspension cable from which is suspended the two pairs of tracks resting on their supporting cables. I've been accused of being a Marxist, yet while Harpo's my favourite, it's Groucho I'm always quoting. Odd, that.
... yes, it would. Indeed, one might even say it does. I'd recomend it if you write it, double promise, double swear.
Hey, we could even team up! What about: I write an outline and my part, you add your knowledge of what is in Oz and North America and possibly redraft my text for impact/terminology/concept, and you post it to draw your established dKos readership?
(On the low side: I'd work slow, whenever I have the time, probably can't do it in one go.) *Lunatic*, n. One whose delusions are out of fashion.
I try to get a HSR diary up toward the end of the week or Saturday (barring one fast paced week when Uni was on Spring Break), if you need a week or two to get going that's fine. I've been accused of being a Marxist, yet while Harpo's my favourite, it's Groucho I'm always quoting. Odd, that.
