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

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

#11

Post by masklinn »

warmwaffles wrote: post #6

I wish this mode of transportation would be practical and affordable here in the US. I like the light rail in Denver, and the subways in San Francisco. Made getting around town really easy and affordable. Unfortunately with the distance between cities here it is more practical to take a flight.

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 (280~320km/h top speed) are superior to plane up to ~1000km, and can remain competitive to 1500km.

(although, though that's much more of a personal advantage, having really shitty ears and great difficulty with pressure equalization the odd train tunnel — even at high speed — is much less painful than going from 0 to 30k ft and back)

[0] modulo specific settings, including the current security theater shit which I don't have to experience on train and considering that most of my experience is on european lines where city center to city center is what you want and airports are commonly 30~40mn away from city center

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

#14

Post by rayiner »

LAMike wrote: post #7

It's only going to be ready by 2045? Won't better tech be developed in that timeframe making this train obsolete?

2045 is only ~30 years from now, and part of the line will be operational by 2027. It seems like a long time for people used to computer technology, but it's a typical generational cycle for industrial technology.

The 787, for example, which is just trickling into fleets now, was in development since the late 1990's (15 years ago). Power technology has developed even more slowly. E.g. the efficiency of coal power plants has only improved by about a factor of two in the last century or so. Heck, even computer technology is progressing more slowly these days. E.g. I wouldn't call Win2k obsolete, but it's 13 years old now!

So yes, the train will be a bit behind the state of the art by the time it's released, but it won't be obsolete.

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

#15

Post by [deleted] »

masklinn wrote: post #9
LAMike wrote: post #7

It's only going to be ready by 2045? Won't better tech be developed in that timeframe making this train obsolete?

The core of today's HST tech dates back to the 50s (the 0-series Shinkansen, the latest of which was only retired in 2008, went in service in 1964). And the first section of Chūō Shinkansen should be open in 2027, with partial opening possible as soon as 2020. FWIW, even standard (non-maglev) high-speed rail construction are not short-term projects, the 300km LGV Est Phase 1 took 5 years between the initial earthwork…

[deleted]

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

#17

Post by cpleppert »

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'm not sure they have solved most of the tunnel boom problem; a major requirement in Japan.

So I wouldn't expect there will be a lot of room for improvement of this design over the next 30-60 years. It will probably cost a lot more than expected as well. Comparatively, there are a lot of new technologies that could deliver major improvements in transportation efficiency and speed without the large capital investment of a maglev line over the next 30-60 years from traditional rail to self-driving cars to new aircraft.

I'm really skeptical of the wisdom of this project to be honest. If you want a maglev design you might as well go with a near-vacuum tunnel and more than triple your speed rather than just increase it by 50%. This would also have the advantage of eliminating the noise issue. I believe China is looking at something like that.

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

#18

Post by frozenport »

rayiner wrote: post #14
LAMike wrote: post #7

It's only going to be ready by 2045? Won't better tech be developed in that timeframe making this train obsolete?

2045 is only ~30 years from now, and part of the line will be operational by 2027. It seems like a long time for people used to computer technology, but it's a typical generational cycle for industrial technology. The 787, for example, which is just trickling into fleets now, was in development since the late 1990's (15 years ago). Power technology has developed even more slowly. E.g. the efficiency of coal power pla…

The real thing is that they already have the train? It would seem they need to solve a few problems and scale up their track.

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

#19

Post by touristtam »

ojii wrote: post #5
pedrocr wrote: post #3

Earlier quoted context omitted.

A quick look at wikipedia[1] shows that these trains often have regenerative braking which means you can have both the wheels and the maglev system stopping the train. So at the same speeds these should be able to brake faster than traditional trains. I assume these have the potential of going significantly faster than normal trains making braking harder. In this test though they didn't reach even the peak speed of n…

The difference is that the TGV you mentioned was a highly modified version just for this speed record. The L0 [1] shown in the video is planned to be the production train and run 500km/h in actual service. [1] http://en.wikipedia.org/wiki/L0_Series_Shinkansen

Then again both train use different technology. Running gear on a TGV is a massive friction generator compared to a maglev, I would think, and consequently the record is very impressive. Still I would love maglev line to be build through Europe.

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

#20

Post by lifeformed »

rayiner wrote: post #14
LAMike wrote: post #7

It's only going to be ready by 2045? Won't better tech be developed in that timeframe making this train obsolete?

2045 is only ~30 years from now, and part of the line will be operational by 2027. It seems like a long time for people used to computer technology, but it's a typical generational cycle for industrial technology. The 787, for example, which is just trickling into fleets now, was in development since the late 1990's (15 years ago). Power technology has developed even more slowly. E.g. the efficiency of coal power pla…

It just seems so foreign to work on something that you might not get to see operational in your lifetime :(
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