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Why Ultra-Efficient 4,000 mph Vacuum-Tube Trains Aren't Being Built

Soulskill posted more than 2 years ago | from the all-about-the-benjamins dept.

Transportation 625

cylonlover writes "In the 1800s, when pneumatic tubes shot telegrams and small items all around buildings and sometimes small cities, the future of mass transit seemed clear: we'd be firing people around through these sealed tubes at high speeds. And it turns out we've got the technology to do that today – mag-lev rail lines remove all rolling friction from the energy equation for a train, and accelerating them through a vacuum tunnel can eliminate wind resistance to the point where it's theoretically possible to reach blistering speeds over 4,000 mph (6,437 km/h) using a fraction of the energy an airliner uses – and recapturing a lot of that energy upon deceleration. Ultra-fast, high efficiency ground transport is technologically within reach – so why isn't anybody building it? This article looks into some of the problems."

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Ultra-efficient first post (-1, Offtopic)

Anonymous Coward | more than 2 years ago | (#40619941)

I am better that Slashdot than you are.

Re:Ultra-efficient first post (5, Funny)

MRe_nl (306212) | more than 2 years ago | (#40620173)

I'm not half as think as you drunk I am.

And also (0)

Anonymous Coward | more than 2 years ago | (#40620425)

Travelling through hyperspace ain't like dusting crops, boy.

Simple (-1, Flamebait)

Anonymous Coward | more than 2 years ago | (#40619949)

Because the simple-minded mythology that people create for themselves is just that: feel-good pseudo-engineering that makes no sense whatsoever.

The same goes for the delusional fever-dream '70s space colonization nonsense. Never, ever going to happen. Ever.

Re:Simple (5, Insightful)

Anonymous Coward | more than 2 years ago | (#40619969)

Yes, like aeroplanes and submarines...

If you don't reach for the stars you will never get there, if you try, you might.

Re:Simple (5, Insightful)

vlm (69642) | more than 2 years ago | (#40620299)

Because the simple-minded mythology that people create for themselves is just that: feel-good pseudo-engineering that makes no sense whatsoever.

For an AC that was a brilliant post. However a little brief. As a "real engineer" who can do estimation and think thru technical problems the biggest problem is the vacuum tube is a waste of money and time and land. For a much smaller scale example you could reduce the "indicated air speed" as a pilot would call it of the TGV in France merely by installing gigawatts worth of walmart kitchen fans pointing such that the train gets a nice tailwind. However if you run the numbers it turns out you can get the same performance increase with merely megawatts of extra train power. Similarly, you could invest in terawatts of distributed vacuum pumps, but it turns out you can go just as fast merely by using gigawatts of train power...

Generally speaking in engineering making the immense part more expensive to make the little part cheaper doesn't pay off, for sufficient value of immense. For example, it turns out to be way the heck cheaper to make a long distance transmission line HVDC than to upgrade every tower long the route higher dielectric strength and taller and bigger footings etc etc. To a crude first approximation this is why sea transport is cheaper per ton-mile than train transport. Another example in the US outside hyperurbanized areas its cheaper to buy each user a taxi and taxi driver than to build passenger rail. I like trains and I like riding in trains but even I realize they're an economic disaster.

In fact it turns out to be cheaper to build a self-levitating and self propelling vehicle than to build a really long and terribly complicated track. I think I shall call my new invention the aeroplane.

The other problem is economic. Any 4000 MPH solution is terrifyingly expensive, so even zero interest expense makes it horrendously expensive. If you can get it cheaper than merely hiring someone far away, or booting up a PC running skype... For example, even during the Concorde era it didn't make financial sense to ship a salesman between NYC and London on the Concorde, it turns out to be cheaper to simply open a sales office in both cities and hire staff in each. Somehow this tremendously more expensive solution is supposed to work even better under conditions where cheaper solutions miserably failed?

Re:Simple (5, Interesting)

NouberNou (1105915) | more than 2 years ago | (#40620483)

Trains are an economic disaster in the US, and it is not for any sort of engineering reason (you can look at pretty much any other industrialized modern country in the world and see that trains actually work out pretty damn well).

Re:Simple (0)

Teun (17872) | more than 2 years ago | (#40620503)

I seems you are under the impression a lot of energy is needed to maintain a vacuum in the tubes.
Providing these tubes are not constructed or maintained by an English water board it would suffice to pump them vacuum only once and then enjoy the fun for almost free.

The containers with cargo and passengers would move along at very low energetic expense.

Oh and because the system would no doubt be underground you don't have to worry about any land use.

I already built one (-1)

Anonymous Coward | more than 2 years ago | (#40619955)

That's why i got to post first!

Re:I already built one (1)

O('_')O_Bush (1162487) | more than 2 years ago | (#40619983)

And the lie is obvious... :p

Why? (1, Interesting)

Anonymous Coward | more than 2 years ago | (#40619959)

Why aren't we shooting people around the city faster than a bullet? Hmm, I don't know. Because it's crazy?

Re:Why? (3, Funny)

O('_')O_Bush (1162487) | more than 2 years ago | (#40620121)

If man was meant to fly, he'd have been born with wings.

Re:Why? (2, Funny)

Anonymous Coward | more than 2 years ago | (#40620261)

And if man wasn't meant to have sex with sheep then God wouldn't have made them so damn sexy!

Re:Why? (4, Funny)

thedonger (1317951) | more than 2 years ago | (#40620345)

XKCD reference [xkcd.com]

vacuum trains?! (4, Funny)

Thud457 (234763) | more than 2 years ago | (#40620123)

this idea sucks

Re:Why? (1)

Anonymous Coward | more than 2 years ago | (#40620155)

Yeah, it makes so much more sense to send people from city to city in a cylinder with wings, traveling almost at the speed of sound ten kilometers above the ground, and where a single defect could cause it to crash into the ground and burst into flames. Compare it to sending people in a evacuated tube at multiple times the speed of sound where any defect could cause them to crash into the walls and burst into flames.

Crazy.

The only answer for the USA (-1, Troll)

Anonymous Coward | more than 2 years ago | (#40619981)

There's only one reason rapid public transportation of any type isn't being built in the USA. Poor people use it, and this country hates poor people.

Re:The only answer for the USA (1)

SJHillman (1966756) | more than 2 years ago | (#40620035)

I will volunteer to be raped by hobos if it means I get to zoom around at 4,000 mph.

Re:The only answer for the USA (2)

Old97 (1341297) | more than 2 years ago | (#40620097)

At the same time?

Re:The only answer for the USA (5, Funny)

MRe_nl (306212) | more than 2 years ago | (#40620211)

It's the mile-low club.

Re:The only answer for the USA (4, Funny)

vlm (69642) | more than 2 years ago | (#40620409)

It's the mile-low club.

Technically its the "mile per second club".

Re:The only answer for the USA (0)

Anonymous Coward | more than 2 years ago | (#40620185)

I will volunteer to be raped by hobos

I see you're still getting a 'b' when you hit the 'm' key.

Re:The only answer for the USA (1)

nschubach (922175) | more than 2 years ago | (#40620285)

You wouldn't need to be raped by hobos if you didn't have an entire freaking train setup to do this. I don't understand why the system can't be designed to use small "taxi" pods where you and your friends can be ferried to many more points in the line without having to rely on where the majority of your train wants to be or stopping for someone else along the way.

Re:The only answer for the USA (3, Insightful)

jdastrup (1075795) | more than 2 years ago | (#40620089)

So all the subway users in New York are house cleaners and students? Wrong. The reason why only poor people use it in other cities is because most public transportation was built around cities that were not designed for it, therefore driving your own car is more efficient, and therefore poor people that don't have cars obviously have to use it. Building public transportation in large spread out city after the fact is a complete waste of money, doesn't matter what kind; e.g. bus, rail, subway, or these new "tubes" - they just won't work in the suburbs.

Re:The only answer for the USA (0)

TheRealMindChild (743925) | more than 2 years ago | (#40620387)

I think you are mistaken. The people riding public transportation do it because they have to. No one wants to ride into the city for an hour, just to get a connecting transfer out of the city to their job... then turn around and do it after work is done. A car may be more efficient AND convenient, but the folks riding public trans can't afford one, let alone the gas money to use it.

Re:The only answer for the USA (0)

Anonymous Coward | more than 2 years ago | (#40620231)

wow you are an idiot.

LOTS of people use commuter trains and subways. Just because your myopic self can't grasp all the users of a tech or service, doesn't mean there aren't any.

Liability (5, Interesting)

robinsonne (952701) | more than 2 years ago | (#40619989)

Who wants to accept the liability if passengers/surrounding objects get turned into goo when a tiny defect causes the 4000 mph object to decelerate in a not-quite-so-planned manner?

Re:Liability (5, Interesting)

geogob (569250) | more than 2 years ago | (#40620103)

Airlines?

Re:Liability (5, Insightful)

O('_')O_Bush (1162487) | more than 2 years ago | (#40620159)

The article mentions this... the problem is, it sets up a false dichotomy. The options aren't no vacuum trains or ones that go at 4k mph... there is a whole range of speeds that these trains could be effective and efficient, and not all will turn passengers into goo if it crashes.

Re:Liability (4, Interesting)

MozeeToby (1163751) | more than 2 years ago | (#40620197)

You're not any more dead than if your airliner falls out of the sky at 500 mph.

Safety is not the real problem. If you really put some research and development into it, you could probably get maglev down to $500,000 per km and probably a similar amount (if not more) for the vacuum tube (compare to $100 million per km right now). Then there's the cost of the trains, running the lines, maintaining vacuum ect. And for any run to make sense it's going to need to be thousands of km long, and every stop you make is going to defeat the purpose so direct lines between major cities are a must. A run from NY to LA would run you several billion dollars just to get started and several hundred million every year after that for maintenance and repair. So, the real question is: is there enough traffic between NY and LA (for example) to recuperate the cost of construction and operations. I highly, highly doubt the answer is yes.

Re:Liability (5, Insightful)

pthisis (27352) | more than 2 years ago | (#40620501)

A run from NY to LA would run you several billion dollars just to get started and several hundred million every year after that for maintenance and repair. So, the real question is: is there enough traffic between NY and LA (for example) to recuperate the cost of construction and operations. I highly, highly doubt the answer is yes.

If it were that cheap it'd be "yes, absolutely, and we're going to hook up every major city as well."

They're talking about spending over $150 billion for the high-speed rail from San Francisco to Los Angeles, and Amtrak's discussing $100 million in track improvements to get TGV-level speeds from Boston to Washington, DC.

Those are the nicest train routes in the country, but they're peanuts compared to how profitable a NY-to-LA in under an hour route would be if it only cost a few billion to get going and several hundred million a year to operate.

Re:Liability (0)

Anonymous Coward | more than 2 years ago | (#40620291)

So, this is to contrast with airplanes?
Tube vs. plane:
Massive new series of partially vacuum tubes for each route you want vs. communications infrastructure and specialized building at each destination you want.
Tube breaks and the entire train 'crashes' into the normally preassured air vs. anything short of losing both wings still has a good chance of gliding into a relatively slow landing.
Crammed into tiny chairs in a high speed tube vs. crammed into tiny chairs in a flying high speed tube.
Specialized docking situation to allow passengers to bypass the low-preassure region without damaging the vacuum vs. specialized docking station so airports can sell $15 slices of pizza.

Ok, 2 wins for planes, 2 ties. And that's just for travel on the same continent, things get much more awkward when you want to build a giant tube across an ocean.

Perhaps.. (2)

ackthpt (218170) | more than 2 years ago | (#40619993)

Perhaps it could work, but the technology and mechanics would have to be pretty darn reliable or people would arrive as pâté

We're having a dickens of a time getting our Bullet Train going in California, which has finally been green-lighted to sell bonds and collect some federal funding.

Re:Perhaps.. (1)

usmc4o66 (1605139) | more than 2 years ago | (#40620091)

But it won't be a bullet train... They are going to use it for "Blended" (read: slow, crappy Amtrak) rail, subway, infrastructure upgrades... It is a joke, and will not solve any traffic problems.

Re:Perhaps.. (1, Insightful)

Dyinobal (1427207) | more than 2 years ago | (#40620115)

You know of all the places to build a bullet train California seems one of the worst places to do it. Forgetting for a moment that the state already has crippling debt, lets think about Earthquakes, which happens to be one of the natural disasters that strike with little to no warning. I can't imagine any sort of high speed mag lev line will have any sort of real earth quake tolerance, but maybe I'm wrong and some physics or engineering major can come on here and tell me why traveling at a huge speed, on a systems that requires a contiguous track in an earthquake prone region is a good idea.

Re:Perhaps.. (2)

j00r0m4nc3r (959816) | more than 2 years ago | (#40620191)

Just maglev the entire mavlev train system.

Re:Perhaps.. (5, Insightful)

glueball (232492) | more than 2 years ago | (#40620213)

Someday maybe the Japanese can figure out how to build a bullet train in an earthquake zone.

Re:Perhaps.. (0)

Anonymous Coward | more than 2 years ago | (#40620223)

I can't imagine any sort of high speed mag lev line will have any sort of real earth quake tolerance, but maybe I'm wrong

Yes, you're wrong, and if you'd thought for a few seconds, you would have realized it. Japan does just fine with their bullet trains, despite having plenty of earthquakes.

Re:Perhaps.. (2)

AgNO3 (878843) | more than 2 years ago | (#40620275)

Yeah those bullet trains in earth quake ridden Japan are always killing people. Oh wait no thats Godzilla.

Earthquake prone (1)

rabenja (919226) | more than 2 years ago | (#40620307)

...like Japan, for instance...

Re:Perhaps.. (2)

TheRealMindChild (743925) | more than 2 years ago | (#40620431)

I don't see a reason these tubes can't shift. If the car is magnetically leveled to the middle of the tunnel, it can take a lot of wiggle room

Government Spending (1)

dokebi (624663) | more than 2 years ago | (#40619997)

It is hard to spend money on infrastructure (*any* infrastructure) in the US. I imagine most of government revenue will be eaten up by tax cuts for the rich and for programs for retirees who vote. Perhaps we can figure out a corporate sponsored infrastructure improvement program (say privately owned bridges, or paying for highway segments for rights to display ads there). I'm not holding my breath.

Re:Government Spending (0)

Anonymous Coward | more than 2 years ago | (#40620319)

Apparently you need a crash course in where government (at the fed, state and local levels) speeds money. Most money is spend on social programs, various forms of welfare, and feel good programs.

The answer is in the photo of the author. (0)

Anonymous Coward | more than 2 years ago | (#40620023)

Look at the photo of the author at the bottom of the page.

I do wish they'd put those things at the top. Saves me the trouble of reading the article when I can plainly see it was written by some douche.

Maybe because... (5, Informative)

Anonymous Coward | more than 2 years ago | (#40620031)

When the British did it [wikipedia.org] they had hella mechanical problems. The smallest glitch with a seal and suddenly your trains aren't moving nearly as fast anymore. You'd have to build two tunnels: the vacuum tunnel for the train, and then a slightly larger outer tunnel that allows for service and leak detection.

Re:Maybe because... (0)

Anonymous Coward | more than 2 years ago | (#40620297)

How long would it take for workers to actually travel to the middle of a tunnel to get said leaks fixed?

Re:Maybe because... (1)

Derek Pomery (2028) | more than 2 years ago | (#40620349)

You'd think we'dve improved techniques in the last 150 years.

Re:Maybe because... (1)

TheRealMindChild (743925) | more than 2 years ago | (#40620467)

Build the tunnel from thick rubber.... treat it like a tire

in the year 3000 (0)

Anonymous Coward | more than 2 years ago | (#40620039)

...in the year 3000 we will have that, I've seen it in Futurama!

Re:in the year 3000 (3, Informative)

jsepeta (412566) | more than 2 years ago | (#40620267)

hopefully the passenger dispersal method will be safer than just dumping us on the curb

G-force (0)

aztrailerpunk (1971174) | more than 2 years ago | (#40620075)

Wouldn't g-forces still apply? Making speeds like that not possible for human travel.

Re:G-force (0)

Anonymous Coward | more than 2 years ago | (#40620139)

Wouldn't g-forces still apply? Making speeds like that not possible for human travel.

Better tell all those pilots and astronauts that what they're doing is impossible, then.

Re:G-force (1)

Iniamyen (2440798) | more than 2 years ago | (#40620175)

As long as you don't accelerate too fast, the human body doesn't care about the relative speed that it's traveling. You have Sir Isaac Newton to thank for that.

Re:G-force (0)

Anonymous Coward | more than 2 years ago | (#40620305)

I don't think it's the acceleration that would worry me... there are many limits on that (power input, for one). It's the sudden, unexpected, and uncontrolled DEceleration that has me worried. At 4000mph in an enclosed tube, it wouldn't take much to send things awry.

MadCow.

Re:G-force (0)

Anonymous Coward | more than 2 years ago | (#40620177)

Wouldn't g-forces still apply? Making speeds like that not possible for human travel.

The speed does not matter. It is the acceleration/deceleration (you should know that, since you mention g-force).

Captcha: underway.

Re:G-force (0)

Anonymous Coward | more than 2 years ago | (#40620235)

Depends on the rate of acceleration and, in the case of turning, the radius of the turn.

Re:G-force (2)

AgNO3 (878843) | more than 2 years ago | (#40620315)

G-force is on our side. Its spectra you have to worry about.

Re:G-force (1)

nschubach (922175) | more than 2 years ago | (#40620369)

Supposedly, you wouldn't accelerate to 4000 mph fast enough or take sharp enough turns to impact the rider much... and most likely, you wouldn't be hitting 4000 mph unless you were travelling very far distances.

Tube to space (0)

Anonymous Coward | more than 2 years ago | (#40620085)

Just out of curiosity, if you were to run a tube from the surface of the earth to outter-orbit (the vacuum of space), would there not already be a vacuum in the tube? Could we not just use that pressure to propel things upwards? Someone school me on this, please. It's 3 minutes shy of quittin' time, so my brain may be misfiring.

Re:Tube to spaceballs (2)

cornface (900179) | more than 2 years ago | (#40620241)

It is more efficient to build a giant robot maid to attach an equally gigantic vacuum cleaner to the outer atmosphere and suck the air out.

Suck...suck...suck.

Re:Tube to space (1)

Iniamyen (2440798) | more than 2 years ago | (#40620279)

You could, but once you used that vacuum to propel something, you'd essentially have a stack of regular atmosphere inside the tube. This would have to be pumped out again before you could re-use the tube. The stack of atmosphere wouldn't naturally evacuate, because you still have Earth's gravity pulling on it.

Re:Tube to space (1)

mmell (832646) | more than 2 years ago | (#40620379)

Yes, as long as your vehicle is lighter than the quantity of air it displaces (i.e., lighter than air). It's not like that tube will "suck" atmosphere up into space - after all, our atmosphere is directly exposed to space everywhere, and yet it hasn't been "sucked" up. (There is no such thing as "suction" - only lower pressure)

Now, once you get several miles up, yes, there will be a vacuum in the tube up there (again, more accurately, not a "vacuum" - just way less air pressure than you and I are used to). Incidentally, it's physically impossible to suck water up a straw beyond around thirty-odd feet (depending on the barometric pressure). BTW, if building a space elevator is beyond our current technological ability, a space straw is really beyond us.

It's a couple hours shy of quittin' time here, so my brain hasn't started firing yet.

Re:Tube to space (0)

Anonymous Coward | more than 2 years ago | (#40620415)

wouldn't work for the same reason the atmosphere doesn't get sucked out into the vacuum of space - it's held down by gravity. Now, If you could somehow make an anti-gravity tube, then you'd be talking.

Re:Tube to space (0)

Anonymous Coward | more than 2 years ago | (#40620433)

The air will be pulled down by gravity with an equal pressure, and thus the system would reach a boring equilibrium.

The Real Problem (1)

Jetra (2622687) | more than 2 years ago | (#40620093)

It doesn't mention the fact of how many Gs the body would be under. Yes, I know it's not instantaneous, but that speed still might cause some serious problems regarding your organs wanting to stay behind.

Re:The Real Problem (1)

Iniamyen (2440798) | more than 2 years ago | (#40620341)

Why is this such a common misconception? Your body does not care what SPEED you are traveling, only how quickly your speed changes (acceleration.) If you average a 0-60mph time of 15 seconds (rather slow), then you could reach 4,000mph in just over a minute, as drag would not increase appreciably. Are you saying that a 0-60mph time of 15 seconds is enough to physically injure you?

Re:The Real Problem (1)

Iniamyen (2440798) | more than 2 years ago | (#40620371)

Sorry, bad maths. It would work out to be 15 minutes to reach top speed. Still acceptable =)

Re:The Real Problem (1)

nschubach (922175) | more than 2 years ago | (#40620389)

Eventually your organs catch up to your body just like your body catches up to the train.

Related questions... (1)

fahrbot-bot (874524) | more than 2 years ago | (#40620101)

...high efficiency ground transport is technologically within reach – so why isn't anybody building it?

... Why aren't space ships with warp drive being built, under-sea cities, space elevator or a thousand other things people have thought of over the years? Where are my self-cooking hot dogs? Why do hot dogs come in packages of 10 but hot-dog rolls in packages of 8?

How about something practical that all people could use like free, universal health care or an end to greed, war and other (ultimately) petty squabblings?

Re:Related questions... (3, Funny)

j00r0m4nc3r (959816) | more than 2 years ago | (#40620219)

Why do hot dogs come in packages of 10 but hot-dog rolls in packages of 8?

Two for Fido.

Re:Related questions... (1)

caknuckle (2521404) | more than 2 years ago | (#40620321)

Why do hot dogs come in packages of 10 but hot-dog rolls in packages of 8? Two for Fido.

OR....so they force you to buy two packages of buns. When hot dog makers start putting 8 to a pack, bun makers will conveniently scale down to 6 buns and call it the "economy pack", and remove all 8 bun packages from the shelf.

Re:Related questions... (1)

Iniamyen (2440798) | more than 2 years ago | (#40620449)

That assumes that you are buying the buns in response to the hot dogs. What we need are some recipes that use only the buns, without the dogs. That would turn the tables on those fat cat hot dog industry bastards.

Re:Related questions... (-1)

Anonymous Coward | more than 2 years ago | (#40620259)

HAHAHAA nothing is free dumbass. You mean "healthcare where the government forces those who work hard to pay for care for those who don't."

Re:Related questions... (0)

AgNO3 (878843) | more than 2 years ago | (#40620351)

free health care? OR do you mean TAX FUNDED healthcare? Cause I'm not going to med school and then residence then specialization and spending 15 years doing it if I can make the same pay going to school for 4-6 years.

Safety is not an issue (4, Insightful)

Hentes (2461350) | more than 2 years ago | (#40620125)

Use it for cargo first, and if there are no problems we can start using it for passengers. But the cost is a big obstacle.

Not buying my tickets yet .. (4, Informative)

n5vb (587569) | more than 2 years ago | (#40620135)

Wake me up when someone actually manages to build a tunnel anywhere near that size that's vacuum tight and has a realistic notion of what size and number of vacuum pumps would be required to keep a high enough vacuum in it. Oh, and handling the exterior pressure loading without risk of accidental implosion would be nice. ;)

The other problem which is less trivial than it might seem is how to get people and cargo (and possibly vehicles) onto and off of these trains without breaking the vacuum .. really big airlocks at the stations maybe? .. and how to evacuate one of these safely in case of an emergency on the main line ..

Re:Not buying my tickets yet .. (0)

Anonymous Coward | more than 2 years ago | (#40620247)

Also....

What if there is traffic?

This project is not cost effective (0)

Anonymous Coward | more than 2 years ago | (#40620149)

The eurotunnel is 32 miles long, took 6 years to build, and it cost £9 billion to build. A standard railroad typically costs $2 million per mile to build. Now you want to build a pneumatic vacuum tunnel a few hundred miles long or more? Trains and airlines make all their money from transporting goods, not from transporting passengers who don't want to pay a lot for a ticket. I think you need to a good economics 101 course!

Re:This project is not cost effective (0)

Anonymous Coward | more than 2 years ago | (#40620435)

The eurotunnel is 32 miles long, took 6 years to build, and it cost £9 billion to build. A standard railroad typically costs $2 million per mile to build. Now you want to build a pneumatic vacuum tunnel a few hundred miles long or more? Trains and airlines make all their money from transporting goods, not from transporting passengers who don't want to pay a lot for a ticket. I think you need to a good economics 101 course!

I got the other one : Bad Economics 101. The most memorable moment was that the best way to stimulate was to fly over and dump currency.

What do the guys do with the Vacuum Train if the car comes to a halt a hundred miles from a station?

Re:This project is not cost effective (2)

SlashDotDotDot (1356809) | more than 2 years ago | (#40620471)

I question your $2 million per mile figure. Minneapolis/St Paul is currently building a 10 mile light rail line at a cost of $1 billion. ($100 million per mile) That's at street level through a moderately dense urban area and it includes the cost of all the stations. Maybe $2 million per mile is the cost through flat countryside with no stations and land acquired for free?

kinetic energy (3, Insightful)

joostje (126457) | more than 2 years ago | (#40620153)

it takes more or less the same amount of energy to accelerate from 3,000 to 3,050 mph (4,828 to 4,908 km/h) as it takes to get from 50 to 100 mph (80 to 161 km/h)

No, kinetic energy goes with the square of velocity. So to accellerate from 3000 to 3050 mph takes as much as to get from 0 to 550 mph. The rest of the article may be interesting, but it's strange they make errors like that.

Re:kinetic energy (1)

GodfatherofSoul (174979) | more than 2 years ago | (#40620395)

Ruh?

Go figure (0)

Anonymous Coward | more than 2 years ago | (#40620161)

I would have thought it was the expense of building and pumping-down a leak-free vacuum tube 8 to 10 feet in diameter and hundreds or even thousands of miles long.

Or actually two of them, since people probably want to go in both directions.

And maintaining it leak-free for years, or hopefully, decades of use.

Nah, it must be politics.

Vacuum-Tube Trains (5, Funny)

fustakrakich (1673220) | more than 2 years ago | (#40620165)

They do have a warmer more 'natural' sound

Re:Vacuum-Tube Trains (1)

ColdWetDog (752185) | more than 2 years ago | (#40620255)

They do have a warmer more 'natural' sound

In a vacuum, no one can hear you scream.

Re:Vacuum-Tube Trains (0)

Anonymous Coward | more than 2 years ago | (#40620343)

They do have a warmer more 'natural' sound

In a vacuum, no one can hear you scream.

its a feature

Ah Yes Vacuum Tubes ... (0)

Anonymous Coward | more than 2 years ago | (#40620215)

They sound so much warmer than that transistor-based transportation.

so what if... (0)

Anonymous Coward | more than 2 years ago | (#40620225)

instead, we setup the tubes and don't put them in a vaccum
instead we have the air flow through the tunnel at an optimum level for the train
past a certain speed, wind resistance becomes like trying to drive a car through a gigantic block of butter
matching train speed to relative air speed would be more cost effective than maintaining a constant vaccum

Why the exagerated speed? (3, Insightful)

geogob (569250) | more than 2 years ago | (#40620301)

I don't get what the author of this article wins by proposing such ridiculously exagerated speeds. Sadly, this kind of nonse plagues sci-fi-like tech news since tech news exists.

I see no need for a train going at 6000 km/h. But the idea could be interesting even at much lower speeds. A vaccuum tunel based maglev going at 600 km/h would already be quite at win for energy efficiency. But as long as it costs less to build and maintain reactors to power electical trains, you won't see any of these around.

Re:Why the exagerated speed? (2)

GodfatherofSoul (174979) | more than 2 years ago | (#40620465)

More important, you go that fast below ground on an isolated track and you've probably beaten out air travel as a better infrastructure option considering logistics and payloads.

Vactrain (2)

foobsr (693224) | more than 2 years ago | (#40620311)

Probably its time that /. posts links to Wikipedia entries to be at least a little more informative.

If one would have looked up Wp, one could have found this, quote: "Vactrains have occasionally appeared in science fiction novels, including the works of Arthur C. Clarke (Rescue Party, 1946), Ray Bradbury (Fahrenheit 451, 1950), Peter F. Hamilton (The Night's Dawn Trilogy), Joe Haldeman (in his novel Buying Time), Larry Niven (A World Out of Time), Robert A. Heinlein (Friday), Jerry Yulsman (Elleander Morning), and Jasper Fforde (the Thursday Next novels). Flash Gordon (1947) and the movie Logan's Run (1976) featured similar high-speed transport trains. The Space: 1999 TV series, featured a Lunar Vactrain. 23rd century San Francisco has one stretching across the Golden Gate Bridge in Star Trek: The Motion Picture (1979). Earlier Gene Roddenberry television productions, Genesis II and Planet Earth, featured such transport systems.".

CC.

Inertia (0)

Anonymous Coward | more than 2 years ago | (#40620331)

Inertia. Both Literately and Figuratively.

The idea doesn't get off the ground because it requires very expensive technology (sealed vacuum tubes, and magnetic levitation, both which require durable materials and high switching speeds to prevent accidents. If a mag lev crashes from loss of power, it lands and stops moving, not derailing. Now do the same with a vacuum tube with no air friction.

The other side of this, is that you can't get optimal speeds unless it's all flat, at best this means under-sea links, not land-based. The only land-based link that is viable is Alaska/Yukon/NWT/Nunavut to Russia, and that would be intentionally going beneath the ice at the north pole. Think about it, we can't fly over the north pole, and we can't send a ship through it, yet it's a much shorter distance from Seattle than first flying to NYC to get to London.

Re:Inertia (1)

TheRealMindChild (743925) | more than 2 years ago | (#40620493)

;ncpdr

(no closing paren, didn't read)

Article left me unfullfilled (0)

Anonymous Coward | more than 2 years ago | (#40620391)

The basic problems it describes are:

1) Cost for mag lev and plus cost to maintain vacuum - including pin hole leaks.

2) Risk of death from accident/sabotage

But the most interesting vacuum tube mag lev train concept is vertical, not horizontal. I.E. space fountain. The costs for space travel already exceed the costs for mag lev and vacuum maintenance. And as everyone knows, the accident rate is unfortunately rather high (at least for the space shuttle).

It continues to look like a no brainer to build a space fountain.

Uh... (0)

Anonymous Coward | more than 2 years ago | (#40620445)

through a vacuum tunnel

Yeah, that's great for cargo, but human beings can't survive in a vacuum, am I missing something here?

Many reasons, but author demonstrates ignorance (0)

istartedi (132515) | more than 2 years ago | (#40620463)

Add to this the hidden cost of maintaining the vacuum (presumably by constantly pumping air particles out of thousands upon thousands of miles of vacuum tube)

Apparently, the author hasn't heard of airlocks. I just skimmed the article. This was enough to make me not want to read it in detail.

The obvious problems are obvious (1)

Patch86 (1465427) | more than 2 years ago | (#40620469)

The article might as well have cut to the chase- cost.

Japan's non-vacuum-tube, low-speed mag-lev came in at $100 million per kilometre. A 4,000 mph vacuum-tube railway will cost a lot more. Compare with conventional high-speed railways (which are far far slower) at about $10 million per kilometre- which are already considered way too prohibitively expensive to build in any quantity. If you could keep the cost at $100 mill per km, that'd make a London to New York line cost about half a trillion US dollars. Just for the set-up cost. Excluding the cost of maintaining 5,500 km of vacuum tubes UNDER THE OCEAN. Got that money spare?

That's without getting into minor performance issues, such as the huge breaking distance or colossal turning circle for something travelling at 4,000 mph. With conventional rail or aircraft it's fairly trivial to connect up a network of cities on a continent. Try playing join-the-dots with European cities with a network with these limitations instead.

Will never happen because (2, Insightful)

Simonetta (207550) | more than 2 years ago | (#40620475)

Will never happen because:
one- The United States is broke. They pissed away all their money on permanent unwinnable wars, housing scams, and Wall-Street bank bailouts. The idea that they would be able to spend trillions of dollars to build 1000 mile long tubes to convey peasants across North America at 4000 MPH is absurd.

two: Present company excepted, but Americans are technologically incompetent at long-term projects. All their bridges and highways are in disrepair, and they can't even get 50MPH trains to run competently. Didn't they once even have a space program?

three: What's the point of moving thousands of people around? For every person in one place, there is a another person in just like them in any place that you would send them to.

four: Walk to any corner and there's a McDonalds, a Bank of America, a Chevron gas station, and a Starbucks. Travel a thousand miles in any direction and you're on a corner with a McDonalds, a Bank of America, a Chevron gas station, and a Starbucks. What's the point of travel?

Physics FTW. (0)

Anonymous Coward | more than 2 years ago | (#40620487)

Put a rail in a vacuum with a 600V potential on it, (same as a train), guess what happens.

In the 1800s??? (0)

Anonymous Coward | more than 2 years ago | (#40620491)

Thanks, dude, now i feel really old. My employer still uses a system like this, even if it's mainly used by sysadmins for beerdistribution:

http://www.youtube.com/watch?v=p8yRjVnl8Yo

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