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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)

#81

Post by e12e »

ekianjo wrote: post #58
larsbot wrote: post #29

Earlier quoted context omitted.

From the article: The line between Tokyo and Osaka is expected to cost approximately $90 billion and it won't be completed until 2045 I think California's high speed rail project should be cancelled, but big infrastructure projects do cost a lot of money and take a long time, both in Japan and the US.

That's precisely why these kind of high speed trains have no future. They cost way too much in infrastructure.

Right. And the initial railways that crossed the US were affordable?

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

#82

Post by icegreentea »

vedant wrote: post #57
Patrick_Devine wrote: post #39

Earlier quoted context omitted.

Air density on the ground. Air is a lot soupier close to the surface in the troposphere vs way up high in the stratosphere.

Most commercial flights are actually in the troposphere, which is about 17km deep in the temperate zone. Your point is still right: air density at 36000ft is ~0.37 kg/m^3, as opposed to 1.23 kg/m^3 at sea level.

To build on this, the drag force varies linearly with fluid density and quadraticly with velocity, so the four-fold increase in fluid density from airplane altitude to sea level corresponds to a doubling in velocity. Which is actually the difference we see! Cool!

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

#83

Post by moca »

masklinn wrote: post #4

Not bad, it's not completely clear from the article but checking wikipedia L0 should be a "production" maglev, similar to Shanghai's Transrapid (except Transrapid's maximum operating speed is 410km/h. It did reach 501km/h in early test runs but doesn't reach that on scheduled traffic). It's good to see that tech finally get in production (Japan's maglev demonstrators first breached 500km/h in 1979). FWIW, if all goes…

Considering the cost, time of construction, time saving, the project doesn't seem to make much sense. China already dropped maglev due to high cost. On the other hand, Japan is making very slow progress on cleaning up its nuclear mess and almost all of its nuclear reactors are suspended right now. Why a new railway is more important than nuclear disaster in hand?

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

#84

Post by uniclaude »

moca wrote: post #83
masklinn wrote: post #4

Not bad, it's not completely clear from the article but checking wikipedia L0 should be a "production" maglev, similar to Shanghai's Transrapid (except Transrapid's maximum operating speed is 410km/h. It did reach 501km/h in early test runs but doesn't reach that on scheduled traffic). It's good to see that tech finally get in production (Japan's maglev demonstrators first breached 500km/h in 1979). FWIW, if all goes…

Considering the cost, time of construction, time saving, the project doesn't seem to make much sense. China already dropped maglev due to high cost. On the other hand, Japan is making very slow progress on cleaning up its nuclear mess and almost all of its nuclear reactors are suspended right now. Why a new railway is more important than nuclear disaster in hand?

Remember how governments work. Transportation and energy are different budgets managed by different entities.

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

#85

Post by snogglethorpe »

Pitarou wrote: post #78

Sigh. I've got nothing against thinking big, but this is not the kind of investment Japan needs right now. BIG money, for only an incremental improvement. (The public transport infrastructure is already very good.) If the boys in the ministry really wanted to boost Japan, they'd be investing in renewable energy, not playing with train sets. But there are too many vested interests...

The "ministry" isn't paying for it—it's being privately financed by JR central (which is a private company).

From Wikipedia: "On December 25, 2007, JR Central announced that it plans to raise funds for the construction of the Chuo Shinkansen on its own, without government financing."

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

#86

Post by snogglethorpe »

uniclaude wrote: post #84
moca wrote: post #83

Earlier quoted context omitted.

Considering the cost, time of construction, time saving, the project doesn't seem to make much sense. China already dropped maglev due to high cost. On the other hand, Japan is making very slow progress on cleaning up its nuclear mess and almost all of its nuclear reactors are suspended right now. Why a new railway is more important than nuclear disaster in hand?

Remember how governments work. Transportation and energy are different budgets managed by different entities.

Not to mention that the Chuo Shinkansen will be privately financed, and is being built by a private company, JR central. They almost certainly need government cooperation (you can hardly escape that with something so huge and covering so much geographical area), but this isn't a Japanese government project, and the government isn't paying for it.

From Wikipedia: "On December 25, 2007, JR Central announced that it plans to raise funds for the construction of the Chuo Shinkansen on its own, without government financing."

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

#87

Post by Pitarou »

snogglethorpe wrote: post #85
Pitarou wrote: post #78

Sigh. I've got nothing against thinking big, but this is not the kind of investment Japan needs right now. BIG money, for only an incremental improvement. (The public transport infrastructure is already very good.) If the boys in the ministry really wanted to boost Japan, they'd be investing in renewable energy, not playing with train sets. But there are too many vested interests...

The "ministry" isn't paying for it—it's being privately financed by JR central (which is a private company). From Wikipedia: "On December 25, 2007, JR Central announced that it plans to raise funds for the construction of the Chuo Shinkansen on its own, without government financing."

An accounting trick to keep the debt off the government books.

A project of that scale could not possibly happen in Japan without whole-hearted government support.

(I know I sound like a grumpy cynic, but I've learnt from experience that one can rarely go wrong being cynical about powerful Japanese institutions.)

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

#88

Post by Pitarou »

jpatokal wrote: post #60
mrb wrote: post #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

It's one thing to set test records with test equipment, and another to set them with production equipment -- this model is the actual train they're going to run on the line. Kind of like how the Bell X-1 was the first supersonic aircraft, but the Concorde was the first commercial supersonic aircraft. (And I have a sneaky suspicion that Japan's maglev, running in a depopulating country with economy in a terminal downw…

The comparison with the Concorde was the first thing that sprang to mind with me, too.

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

#89

Post by Pitarou »

stcredzero wrote: post #45

I wonder how fast they could make the train if it had the smaller cross-sectional area of the Hyperloop pods? Another way to put it: What about a 310 mph maglev on a solar-panel shaded elevated track between SF and LA?

Even better, do away with MagLev altogether, and have them "float" the way an air hockey puck does.

(You have read Elon Musk's proposal, haven't you?)

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

#90

Post by snogglethorpe »

Pitarou wrote: post #87
snogglethorpe wrote: post #85

Earlier quoted context omitted.

The "ministry" isn't paying for it—it's being privately financed by JR central (which is a private company). From Wikipedia: "On December 25, 2007, JR Central announced that it plans to raise funds for the construction of the Chuo Shinkansen on its own, without government financing."

An accounting trick to keep the debt off the government books. A project of that scale could not possibly happen in Japan without whole-hearted government support. (I know I sound like a grumpy cynic, but I've learnt from experience that one can rarely go wrong being cynical about powerful Japanese institutions.)

The government is certainly involved to a degree—you can hardly build something of this scale otherwise, there are simply too many third parties to deal with—but I've seen no reason to think that the financing is "an accounting trick."

Simple general cynicism is all well and good, but it isn't really worth much absent actual evidence.

This is particularly true in the case of JR-central / east / west, which are well-run and solid companies, and a model for how to do privatization successfully.

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