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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)

#61

Post by tgb »

powertower wrote: post #50
tgb wrote: 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, an…

Thanks for the answers everyone. One more question:

Can maglevs use jet propulsion to go faster?

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

#62

Post by kposehn »

larsbot wrote: post #51
melling wrote: post #38

Earlier quoted context omitted.

It's going to be even more expensive in 30-40 years to build a maglev between LA and SF. Much of the cost is in obtaining the land. Wouldn't it be cheaper to build the first train now then turn it into a 320 mph maglev in 40 years?

The cost is going to be high, maybe $100 billion by the time the project is done. Even with the feds helping, that is a huge sum. Are we really going to get the most "bang" for our bucks? How often do people travel between LA and SF anyways? Improve BART, VTA light rail and CalTrain (in the Bay Area), and I suspect it will have a much larger positive impact on the lives of more people.

There would be a huge benefit from a high speed rail network in California, for sure.

My main issue is the way they are going about it, which is a highly politicized construction process along with some really out-of-order prioritization.

It would be much better to start with the low hanging fruit, like grade separation and electrification of Caltrain. That line would benefit immensely from some major upgrades, such as longer station platforms. To be fair, the most recent round of upgrades (ctc, quadruple track sections, new rolling stock) have been very well done.

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

#63

Post by kposehn »

moca wrote: post #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 actu…

One important note: the Chinese HSR is also operating at reduced speed for safety and rail wear reasons.

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

#64

Post by seanmcdirmid »

chiph wrote: post #42
rsync wrote: 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's share of federal support vs. taxes paid are much lower than those of southeastern states. If anything, the southeast (ironically, conservative and anti-tax) has been and continue to steal money from California (the opposite), not the other way around.

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

#65

Post by kposehn »

masklinn wrote: post #11
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 (28…

The pressurization issue is no longer a problem - at least with the Japanese designs.

They run their tracks right next to each other, so trains are designed to not suffer major pressure changes from passing trains or tunnels.

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

#66

Post by larsbot »

Anechoic wrote: post #55
larsbot wrote: post #51

Earlier quoted context omitted.

The cost is going to be high, maybe $100 billion by the time the project is done. Even with the feds helping, that is a huge sum. Are we really going to get the most "bang" for our bucks? How often do people travel between LA and SF anyways? Improve BART, VTA light rail and CalTrain (in the Bay Area), and I suspect it will have a much larger positive impact on the lives of more people.

* How often do people travel between LA and SF anyways?* According to the WSJ, 6 million people per year travel between LA & SF via air every year. I can't find highway numbers, but I gotta believe it's about the same order of magnitude, if not higher. Improve BART, VTA light rail and CalTrain (in the Bay Area), and I suspect it will have a much larger positive impact on the lives of more people. All of the above nee…

Cal-HSRA predicts that by 2040 the train will reduce highway miles traveled by 10 million miles a day[1]. For comparison, in May 2013, there were 15.3 billion miles of travel just on California highways[2]. A reduction of 10 million miles a day would be about 2%, and assuming people continue to move into the state, the number of highway mile traveled per day will likely be quite a bit higher in 2040 than it is today.

I don't know, it just doesn't seem like a very compelling argument to me. The state doesn't have unlimited resources. Spend the money where it will do the most good.

[1] http://www.hsr.ca.gov/docs/newsroom/fact%20sheets/Good%20for...

[2] most recent month with available statistics, lots more data available here http://traffic-counts.dot.ca.gov/

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

#67

Post by Anechoic »

larsbot wrote: post #66
Anechoic wrote: post #55

Earlier quoted context omitted.

* How often do people travel between LA and SF anyways?* According to the WSJ, 6 million people per year travel between LA & SF via air every year. I can't find highway numbers, but I gotta believe it's about the same order of magnitude, if not higher. Improve BART, VTA light rail and CalTrain (in the Bay Area), and I suspect it will have a much larger positive impact on the lives of more people. All of the above nee…

Cal-HSRA predicts that by 2040 the train will reduce highway miles traveled by 10 million miles a day[1]. For comparison, in May 2013, there were 15.3 billion miles of travel just on California highways[2]. A reduction of 10 million miles a day would be about 2%, and assuming people continue to move into the state, the number of highway mile traveled per day will likely be quite a bit higher in 2040 than it is today.…

A reduction of 10 million miles a day would be about 2%,

In highway terms, that's a significant reduction. A reduction on the order of 1-3% (it depends on a number of factors including number of lanes, and distance between exits) can get you from LOS F traffic (stop & go) to LOD C/D traffic (heavy, but moving traffic).

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

#68

Post by Anechoic »

kposehn wrote: post #59
Anechoic wrote: post #56

Earlier quoted context omitted.

The section they are construction is a section that a) will need to be built anyway, and b) be used as a test section to iron out the inevitable kinks that will pop up. The logic is that if a project is going to run into problems (which any large project, including this one, will) you may as well do the easier part first to make the later harder parts go more smoothly.

It would be logical to do that if it were a section that would see some measure if high speed use. The section which would see that would be from Martinez to Davis. That segment sees many capital corridor trains daily and would immediately benefit from high speed service. What they are working on now sees a small fraction of the ridership, iirc.

It would be logical to do that if it were a section that would see some measure if high speed use.

Not necessarily - a lightly traveled starter corridor works well for a new system in terms of minimizing disruptions when the inevitable problems crop up.

To be honest, if it were up to me, I would recommend starting it where it would get the most ridership, but the CHSRA has a legitimate argument here. Also the project can more easily deal with adverse impacts in "the middle of nowhere" better then it could in a more heavily populated area.

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

#69

Post by superuser2 »

masklinn wrote: post #11
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 (28…

Amtrak Hiawatha is an excellent and well-used "traditional" passenger rail line. MilwaukeeChicago in 91 minutes. Almost never late or slow, zero gate security or even ticket checks, convenient Passbook-compatible e-tickets checked by the conductor, comfortable seats, sufficient legroom, 110VAC at every window, takes you to the middle of Chicago with direct or easy access (> 3 bus stops) to every major CTA line and the Metra Electric.

The only things I'd really change are the price ($48 round-trip is a bit steep as a college student) and the lack of wi-fi. The vast majority of commuting professionals have cellular modems though.

It's really great to be able to move between cities in reasonable time without owning a car, buying gas and insurance, or trying to find somewhere to park for less than the price of a firstborn son anywhere useful in Chicago.

I've pulled out my iPhone speedometer app on the train and it clocks at around 80 in the middle of nowhere, 65ish in the northern Chicago suburbs.

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

#70

Post by [deleted] »

powertower wrote: post #50
tgb wrote: 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, an…

[deleted]
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