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Japan's maglev train runs test at over 310 mph (with video)

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41–50 of 95 posts

Re: Japan's maglev train runs test at over 310 mph (with video)

#41
The price and time-line estimate make me sad and pessimistic for some reason. 30 years and $90 billion just to pull a fast train line between two cities in Japan? How long and how expensive then will real futuristic projects be, like colonization of other planets, space elevators, fusion reactors and so on?

Re: Japan's maglev train runs test at over 310 mph (with video)

#42
post #26
post #12

To put this into perspective, the distance from Tokyo to Osaka is 506KM. It's roughly comparable to: * Ottawa->Toronto (449KM) * LA->San Francisco (622KM) * Washington DC->NYC (363KM)

310 mph in 2013. As opposed to 220 mph top speed in the year 2029 for california "high speed" rail. What a bright, wondrous future we will all be living in!

California will never build their line. They'll soak up the federal money in study after study, and will ultimately decide it's uneconomical. In the meantime, projects like the Southeastern High Speed Rail Corridor¹, which is actually acquiring right of way and straightening rail lines to permit high speed travel, will be starved of funds.

¹ http://www.sehsr.org

Re: Japan's maglev train runs test at over 310 mph (with video)

#43
post #41

The price and time-line estimate make me sad and pessimistic for some reason. 30 years and $90 billion just to pull a fast train line between two cities in Japan? How long and how expensive then will real futuristic projects be, like colonization of other planets, space elevators, fusion reactors and so on?

I wonder how much they're paying for land and tech development in that figure - doing something the first time is often rather expensive.

Re: Japan's maglev train runs test at over 310 mph (with video)

#44

Earlier quoted context omitted.

Depends on the cities. NY-SF by train will remain nonsense forever, but the eastern seaboard and a bunch of other clusters (LA-SF, Great Lakes stuff, I think the obama admin had a map of zones they wanted to put HSR proposals for a few years back) could be serviced by high-speed train, even more so with maglev (which extends the competitive range of train against plane) My personal rule of thumb[0] is modern HSTs (28…

Even with the fact that planes fly slower now than in the 60s, I'll gladly fly DEN-SFO. I can be finishing dinner in Palo Alto when you're in the Salt Flats.

On a train, you could comfortably eat dinner on the way.

Re: Japan's maglev train runs test at over 310 mph (with video)

#46
post #42
post #26

Earlier quoted context omitted.

310 mph in 2013. As opposed to 220 mph top speed in the year 2029 for california "high speed" rail. What a bright, wondrous future we will all be living in!

California will never build their line. They'll soak up the federal money in study after study, and will ultimately decide it's uneconomical. In the meantime, projects like the Southeastern High Speed Rail Corridor¹, which is actually acquiring right of way and straightening rail lines to permit high speed travel, will be starved of funds. ¹ http://www.sehsr.org

California will never build their line.

CA HSR authority signed a construction contract with Tutor Perini to start construction in the coming weeks. It's happening.

* In the meantime, projects like the Southeastern High Speed Rail Corridor [..] will be starved of funds.*

This isn't an either/or situation, we can (and are) doing both.

Re: Japan's maglev train runs test at over 310 mph (with video)

#47

I can't imagine there won't be major improvements to conventional high speed rail that will be able to run on existing lines. This requires an entirely new track that can't be used for anything else and the trainset itself can't be upgraded as easily as it is tied to the track. These will be also limited by the noise they produce; even if they can go faster in theory noise pollution is going to be a major issue as is…

I think maglevs are actually quieter and have reduced rail\line wear than conventional track already. Though i think a partially evacced tube would be amazing as well.

Maglev is quieter (much quieter) than conventional rail at lower speeds (below ~ 90 mph) but at higher speeds, once the aerodynamic noise region kicks in, they get very loud very quickly.

Re: Japan's maglev train runs test at over 310 mph (with video)

#48
The article does not mention it, but 310 mph is still below previous maglev's speed records, done 10-15 years ago(!) on the same test line:

361.0 mph in December 2003

343.0 mph in April 1999

329.9 mph in December 1997

See http://en.wikipedia.org/wiki/SCMaglev#Manned_records

Re: Japan's maglev train runs test at over 310 mph (with video)

#49
Shanghai has been operating Maglev line for more than 6 years, see [1] and [2]. The top speed is 431km/h and 268 mph. The Japanese line will have much higher capacity as the Shanghai one is not full production design, but I don't think it has material advantage. The real challenge is economics and noise, and China decided to go with conventional high speed railway system. Even HSR was designed for 350km/h, it is actually operated at 270-300 km/h to reduce operating cost.

1. http://en.wikipedia.org/wiki/Shanghai_Maglev_Train 2. https://www.youtube.com/watch?v=y-54gBLwK3s

Re: Japan's maglev train runs test at over 310 mph (with video)

#50
post #31

Why are maglevs so much slower than airplanes? We're looking at a factor of 2 difference and airports don't take over 30 years to install. Isn't the point of a maglev to reduce the friction against the ground, so aren't both planes and maglevs fighting primarily against air resistance? Or is it not that they can't go faster, just that it's too loud or they need to turn too much or something?

I don't think it has much to do with air density as it does with guideway inductivity issues - which would limit it's top speed (aside from the obvious things like how curved the path is, if and where it has to make more gradual stops and turns, etc).

Jet propulsion and magnetic propulsion are fundamentally different. There are limits to what those magnets can push/pull, how much energy can be put into the system, and the stresses involved coming from the fields.

http://en.wikipedia.org/wiki/Electromagnetic_propulsion

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