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China laying tracks for 1,000km/h maglev trains

asiatimes.com

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Re: China laying tracks for 1,000km/h maglev trains

#381

Post by rb808 »

dheera wrote: post #318
NamTaf wrote: post #82

I’m not sure if it’s just lost in translation, but Wuhan to Guangzhou isn’t even 1000 km so I don’t know where they get the 2200 km they’re quoting. That’s likely a figure for GZ to Beijing. I have used the high speed line between Wuhan and GZ (and through to HK) several times. It’s currently a 4.5 hour direct journey (once per day) or a 5 hour journey if you change at GZ or Shenzhen. The HSR is 300ish km/h at the mo…

I think 1000 km/h travel would bring HUGE benefits. State-of-the-art high-speed trains at 350 km/h tend to waste less time than planes for distances shorter than about 1000 km if you include the time it takes to get to the airport, check-in, go through security, and all that nonsense. Beyond 1000 km journeys, planes tend to be more time-saving. 1000 km/h is about the cruising speed of an aircraft so if it were possib…

The problem is any accident at that speed everyone on the train or near vicinity is toast. Even a plane coming in to land is around 300km/h.

Re: China laying tracks for 1,000km/h maglev trains

#382

Post by beerandt »

Someone wrote: post #269
NeedMoreTea wrote: post #110

Earlier quoted context omitted.

Since when is air ever greener than rail? Everything I've seen puts air at a hugely higher carbon impact.

https://en.wikipedia.org/wiki/Energy_efficiency_in_transport... doesn’t show huge differences in energy usage per passenger-kilometer, so _if_ both get powered by burning oil or coal, I would think the carbon impact isn’t hugely different, either. Reason probably is that, at long distance, lower air resistance at height starts to count. Also, it’s easier to move planes around than to move rail tracks around, so if a…

>Reason probably is that, at long distance, lower air resistance at height starts to count.

This isn't as big a factor as you might think. While older aircraft were optimized for design/cruise altitude, modern jets are designed to account for the imposed altitude restrictions and speed limits of departure and approach. They also have a much wider/efficient operating envelope, and due to improved logistics, are dispatched, loaded, and operated more appropriately wrt to flight plan profiles.

Re: China laying tracks for 1,000km/h maglev trains

#383

Post by microcolonel »

saagarjha wrote: post #296
microcolonel wrote: post #292

Earlier quoted context omitted.

> yep - once u factor in the TSA body shakedown and traffic to airport, then it about evens out air travel. That's a problem that will be replicated exactly for boarding a train destined to travel at 278m/s. The consequences for a major security failure on a high speed train are, if anything, more dire than those for even a very large passenger aircraft. An 800,000kg barely-subsonic chain of rigid torpedoes barreling…

You can’t really hijack a train to hit a specific building, as you can with a plane.

> You can’t really hijack a train to hit a specific building, as you can with a plane.

Setting aside hijacking, which would not be the mechanism for a train attack anyway, the more likely attack on an airplane is suicidal self destruction at this point I would think, with all the new mechanisms in place.

If TSA is this silly with planes, given the relative lack of attractive plans open to attackers now, what makes you think they won't get even sillier with trains than they already have.

As for hitting a specific building, that depends: does your high speed rail line pass near any attractive targets? If the train is 800,000kg (not unreasonable I think?) and is travelling at the rated 280m/s or thereabouts, that's about 31GJ (please check my math) or 7.5 ton TNT equivalent of sheer momentum that can be convinced to continue travelling in an undesirable direction.

Seems like it may be a bit of a risk, at least enough that somebody could be convinced to thoroughly screen passengers.

Re: China laying tracks for 1,000km/h maglev trains

#384

Post by microcolonel »

weberc2 wrote: post #301
microcolonel wrote: post #292

Earlier quoted context omitted.

> yep - once u factor in the TSA body shakedown and traffic to airport, then it about evens out air travel. That's a problem that will be replicated exactly for boarding a train destined to travel at 278m/s. The consequences for a major security failure on a high speed train are, if anything, more dire than those for even a very large passenger aircraft. An 800,000kg barely-subsonic chain of rigid torpedoes barreling…

I get that it's moving fast, but what's the specific threat model? Terrorists hijack the train and somehow drive it off the tracks? Presumably it's easy enough to secure the "cockpit". They could blow it up, but is that dramatically worse than blowing up a train moving 50 mph (genuine question, I'm not sure about the physics)? Especially as these trains don't carry fuel, I can't imagine a tragedy on the scale of 9/11…

> But is that dramatically worse than blowing up a train moving 50 mph

Yes, it is extremely bad when 60-100 ton railcars are being thrown around like toys, at nearly the speed (about 30m/s slower than most .45 ACP) some handguns fire bullets.

Re: China laying tracks for 1,000km/h maglev trains

#385

Post by ghettoimp »

deminature wrote: post #205
mrtksn wrote: post #51

Earlier quoted context omitted.

I’m under the impression that the US public want cars not trains and even the current tech celebrity’s vision is to have self driving cars that work together as if they are train carriages and go in a tunnel as if they are metro train carriages. In the rest of the world, people are fine with ride sharing.

People want cars not trains because current trains are such an awful experience. This wouldn't necessarily be the case if trains were improved to the standards of some other countries.

I suspect Americans think trains are an awful experience not because of the trains, but because there will be other people on the trains. It's one part "don't make me interact with a human," and one part "white people don't ride busses."

It might also be one more part actually creepy people, but I bet most folks don't get that far into their evaluation.

Re: China laying tracks for 1,000km/h maglev trains

#386

Post by geomark »

saberience wrote: post #28

So, as someone that lived in New York for 6 years and California for 6 years, stories like this are incredibly depressing. The US is the world's largest economy and should be the shining example of amazing infrastructure, high-tech, green cities, and forward thinking policies. California is an especially egregious example in terms of infrastructure investment: If California was a country it would be the world's fifth…

I hear you. I lived in SoCal for many years and fought the traffic on all those routes you mentioned. When I came back from trips to countries with working mass transit the awareness was even greater.

But I think it's a hard problem in the U.S. Autocratic governments just decide to do something and plow over anyone who gets in their way. The country I live in now is actually starting to lay track for a high speed rail system to connect the centrally located capital and major outlying cities, and all the way to the northern and southern borders. It did take a while to get started, because everyone had to decide how the contracts would be divided up among their cronies and how the kickbacks would be paid. But it is getting done, because if anyone stands in the way the government declares a threat to the security of the country and sends in the soldiers.

Re: China laying tracks for 1,000km/h maglev trains

#387

Post by [deleted] »

saberience wrote: post #28

So, as someone that lived in New York for 6 years and California for 6 years, stories like this are incredibly depressing. The US is the world's largest economy and should be the shining example of amazing infrastructure, high-tech, green cities, and forward thinking policies. California is an especially egregious example in terms of infrastructure investment: If California was a country it would be the world's fifth…

[deleted]

Re: China laying tracks for 1,000km/h maglev trains

#388

Post by edwinyzh »

saberience wrote: post #28

So, as someone that lived in New York for 6 years and California for 6 years, stories like this are incredibly depressing. The US is the world's largest economy and should be the shining example of amazing infrastructure, high-tech, green cities, and forward thinking policies. California is an especially egregious example in terms of infrastructure investment: If California was a country it would be the world's fifth…

Sorry but I'm exciting as a Chinese coz the gov think in long term and do good for the entire country in building such infrastructure.

>>autocratic and repulsive... I agree the govt's autocratic but disagree it's repulsive.

Re: China laying tracks for 1,000km/h maglev trains

#389

Post by weberc2 »

microcolonel wrote: post #384
weberc2 wrote: post #301

Earlier quoted context omitted.

I get that it's moving fast, but what's the specific threat model? Terrorists hijack the train and somehow drive it off the tracks? Presumably it's easy enough to secure the "cockpit". They could blow it up, but is that dramatically worse than blowing up a train moving 50 mph (genuine question, I'm not sure about the physics)? Especially as these trains don't carry fuel, I can't imagine a tragedy on the scale of 9/11…

> But is that dramatically worse than blowing up a train moving 50 mph Yes, it is extremely bad when 60-100 ton railcars are being thrown around like toys, at nearly the speed (about 30m/s slower than most .45 ACP) some handguns fire bullets.

I get that, but it seems strictly better than, for example, blowing up a trail full of oil cars.

Re: China laying tracks for 1,000km/h maglev trains

#390

Post by I_AM_A_SMURF »

saberience wrote: post #28

So, as someone that lived in New York for 6 years and California for 6 years, stories like this are incredibly depressing. The US is the world's largest economy and should be the shining example of amazing infrastructure, high-tech, green cities, and forward thinking policies. California is an especially egregious example in terms of infrastructure investment: If California was a country it would be the world's fifth…

The whole West Coast is a perfect example for this. How does a train between Vancouver and Seattle take 4 freaking hours?
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