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Japan maglev train breaks world speed record again

bbc.co.uk

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Re: Japan maglev train breaks world speed record again

#71

Post by rtpg »

jusben1369 wrote: post #47
jasonkester wrote: post #27

I wonder if we'll ever get back to "High Speed Air" in my lifetime. Back in the 70s, you could rock up at the airport twenty minutes before your flight left, jump on with minimal hassle, and cruise along at 600mph to your destination. Now, you need to endure two hours of having your fingernail clippers confiscated so that you can fly at 500mph to save on fuel costs. That seems to be the true advantage of rail travel.…

In the US we really don't have any rail alternative to flying. I'd love to know how European travellers thinks and weigh up rail (which seems relatively fast and efficient) vs flying. Do you think the two are interchangeable services? Is there a magical breaking point (more than 500km's distance etc) ?

In France there's the issue of train lines basically starting and ending in Paris mean that flights are pretty quick cutting across the country (Lyon-Nantes for example).

But I think most people see domestic flights as a bother more than anything. The love for trains shows in the stats (second biggest per capita usage of trains after Japan), train stations are usually in the dead-center of town, and you don't have to deal with luggage limits.

Re: Japan maglev train breaks world speed record again

#72

Post by worklogin »

pbz wrote: post #18
wahsd wrote: post #14

Earlier quoted context omitted.

Don't be such an idiot. I get it, you enjoy European infrastructure and social democracy. Remember though that you will pay half of the taxes you pay in Germany ... oh, did you just enjoy all the benefits of German infrastructure and society without actually paying any taxes, let alone your whole life? No one is keeping you from remaining in Germany, are they? I can guarantee you they will approve your work permit an…

> You want a double digit billion dollar MagLev train that connects Boise, Idaho with, St. Louise Missouri? That will be another 10% of your income No, just reallocate some of the hundreds of billions spent on wars / military and make something productive.

Pretty sure paying off our debts,educating our kids and fixing the bridges that might collapse at any moment should come before a federally funded train that won't benefit more than 1% of the population.

Re: Japan maglev train breaks world speed record again

#73

Post by [deleted] »

littlejohnk wrote: post #66
cstross wrote: post #29

Earlier quoted context omitted.

Actually, the TGV record was set by a specially-rebuilt train set that was heavily customized -- and the test crew reportedly couldn't stand/walk around the instrument car at speeds over 500km/h due to vibration. (The track they ran the test on was newly-laid and not yet open to regular traffic: they had to replace most of the overhead cables from the stretch where the train hit maximum speed due to arcing and shock…

"the wheel rims were close to supersonic" This doesn't make any sense. The record is around 575 km/h. The speed of sound is 1225km/h. How would the wheel rim be travelling faster than the train? The while rim rotates 1m for every 1m the train travels, surely? Can you explain what you mean?

[deleted]

Re: Japan maglev train breaks world speed record again

#74

Post by maxerickson »

littlejohnk wrote: post #66
cstross wrote: post #29

Earlier quoted context omitted.

Actually, the TGV record was set by a specially-rebuilt train set that was heavily customized -- and the test crew reportedly couldn't stand/walk around the instrument car at speeds over 500km/h due to vibration. (The track they ran the test on was newly-laid and not yet open to regular traffic: they had to replace most of the overhead cables from the stretch where the train hit maximum speed due to arcing and shock…

"the wheel rims were close to supersonic" This doesn't make any sense. The record is around 575 km/h. The speed of sound is 1225km/h. How would the wheel rim be travelling faster than the train? The while rim rotates 1m for every 1m the train travels, surely? Can you explain what you mean?

The top of the wheel is moving faster than the train. If the contact point between the wheel and rail is not slipping, the relative velocity between the wheel at that point and the rail is 0.

To maintain that condition, the top of the wheel has to travel at twice the speed of the train. Imagine a point on the wheel. Each time the train moves ones circumference forward, that point also makes a circular trip of 1 circumference.

So at the top, when the motion of the point relative to the train is full forward, the net velocity is twice the train. At the bottom, when the motion of the point relative to the train is full backward, the net velocity is 0.

There are diagrams and further explanation here: http://physics.stackexchange.com/questions/48234/why-is-the-...

Re: Japan maglev train breaks world speed record again

#75

Post by apendleton »

TillE wrote: post #55
mmaldacker wrote: post #31

Earlier quoted context omitted.

>Back in the 70s, you could rock up at the airport twenty minutes before your flight left This still exists, for example Tegel airport in Berlin. Also, in the 70s there was waaaaaay less traffic in airports so it is simply not a fair comparison. >Sadly, I bet the way we'll end up equalizing this will be that somebody will eventually bomb a TGV and we'll have to start doing the two hour confiscate-your-kids'-apple-jui…

Tegel is fairly unique because each gate has its own security checkpoint. It's definitely a bit less stressful.

Amsterdam Schiphol is like this, too, and yeah, it's great. I think for them it's because they're going for this combination airport/mall/mini-city vibe, and there are enough amenities that they want it to be attractive as a destination, even for people not flying, so they want to keep as much of the airport outside of security as possible.

Re: Japan maglev train breaks world speed record again

#76

Post by apendleton »

CountHackulus wrote: post #48
the8472 wrote: post #42

Earlier quoted context omitted.

That still exists outside the US. Last year I took a flight from germany to a conference in poland and strolled through the airport after checking in. I left the security zone by accident - simply walking through a pair of sliding doors which only open from one side - 10 minutes before departure. But it wasn't a big problem, I simply went through the metal detector/xrays for hand luggage and arrived at the gate with…

That's strange, I flew from Toronto to Budapest through Munich, and Munich was by far the strictest security I encountered. They made my take off my shoes and sweatshirt. So it's maybe not "outside the US" just "in some places."

It's probably a domestic vs. international thing (where "domestic," within Europe, probably includes actual-domestic as well as other destinations inside the Schengen area). To a large degree, US requirements have infected international travel around the world -- you can't fly into the US from a terminal that allowed people that weren't held to approximately the US's standards.

Re: Japan maglev train breaks world speed record again

#77

Post by ant6n »

vilhelm_s wrote: post #28
ant6n wrote: post #20

Earlier quoted context omitted.

I'm not convinced. Some conventional rail operates at close to 400km/h today. This will operate at 500km/h - in 15 years. But it's completely incompatible with existing infrastructure, and thus doesn't allow incremental updates of either the infrastructure or the trains (i.e. no service in the mean time, and no ability to reuse existing tracks and stations in cities). Then consider the amount of research that's been…

I guess the usual counterpoint is: they have to build a new track anyway (the existing one is getting saturated). Building a rail track or a maglev track costs about the same (almost all the cost is making the tunnels), and the maglev track is better , so why not go with the maglev. It was discussed a little bit for the new high speed train line in Britain, but rejected for the reasons you state in your first paragra…

Maybe it's a tech-fetish. The Germans tried the same thing with Transrapid for many years (between Hamburg and Berlin), but just ended up upgrading conventional rail.

Re: Japan maglev train breaks world speed record again

#78

Post by kailuowang »

Imagine NYC to Boston in 40 minutes and the kind of boost it can bring to the innovative power in the region. It will be truly a silicon alley. And imagine two innovative centers in the country competing with each other.

Unfortunately this kind of decisions are not made by innovative people.

Re: Japan maglev train breaks world speed record again

#79

Post by melling »

worklogin wrote: post #72
pbz wrote: post #18

Earlier quoted context omitted.

> You want a double digit billion dollar MagLev train that connects Boise, Idaho with, St. Louise Missouri? That will be another 10% of your income No, just reallocate some of the hundreds of billions spent on wars / military and make something productive.

Pretty sure paying off our debts,educating our kids and fixing the bridges that might collapse at any moment should come before a federally funded train that won't benefit more than 1% of the population.

Yes, we are discussing putting a maglev from St. Louis to Boise, Idaho because someone wanted to show you why it wouldn't work in the U.S. I bet if we thought about it for another second, we'd come up with more suitable places.

Los Angeles to San Francisco 400 miles

Los Angeles to San Diego 150 miles

NYC to Philadelphia 92 miles

NYC to Boston 220 miles

NYC to Washington DC 226 miles

Chicago to St Louis 260 miles

Dallas to Houston 240 miles

Dallas to Austin 200 miles

Austin to Houston 170 miles

Tampa to Orlando 85 miles

Miami to Orlando 235 miles

Re: Japan maglev train breaks world speed record again

#80

Post by wlesieutre »

Someone1234 wrote: post #64
binarymax wrote: post #36

Earlier quoted context omitted.

The security won't get blown out of proportion for trains like air, because while trains can do significant damage to themselves and surrounding buildings - you cant take one and crash it anywhere you like. 9/11 never would have happened with a train. A hijacked plane is a missile.

Trains still have an "end of the line." So, yes, you could if you were going fast enough. Also aircraft security was too much even pre-9/11.

Even if you were going fast enough, you couldn't take one and crash it anywhere you like.

Into the platform at Grand Central, maybe. Into the WTC and Pentagon, not so much.

Some kind of automatically enforced speed limiter when the train detects that it's near the end of the line would probably not be hard to implement, or maybe has been already. IIRC many trains automatically slow for curvy areas of track.

EDIT: http://en.wikipedia.org/wiki/Positive_train_control

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