Why Ultra-Efficient 4,000 mph Vacuum-Tube Trains Aren't Being Built 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."
Liability (Score:5, Interesting)
Re:Liability (Score:5, Interesting)
Airlines?
Re:Liability (Score:5, Insightful)
Re:Liability (Score:5, Insightful)
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.
Sadly in this case, no. You can't financially handle the R+D and building costs to make this thing and plod along at 100 MPH like the Milwaukee to Chicago run does today. Also cannot operate at a mere 500 MPH like a aircraft given the high costs. So you need to run over 500 MPH. The effects on the passengers of a derailment at 550 MPH are not likely to be a lot better than derailment at 4000 MPH. Sort of like how falling 10 stories off a building doesn't turn out ten times better than falling 100 stories.
Re:Liability (Score:4, Interesting)
I dunno - considering the level of catastrophe that happens to vehicles going 4000 miles through air when a paint chip strikes them, making a vehicle that operates a minuscule fraction of a millimeter from walls going by at that speed without turning into molten slag seems pretty difficult. I can argue that it _might_ be possible to extend our present knowledge and technology to build a 550 MPH (800 KMH?) vehicle that could survive most minor events - I would think that making derailment impossible would be one useful approach. But at 4000 MPH even a bump a millimeter high - anywhere on the hundreds of miles of wall - would be beyond fatal as any minor removal of material would cause the removed material to propagate and become a storm of removed material.
I will note that many stores still have very useful vacuum-based paperwork distribution systems to ship receipts or something from checkstands to the central office. So vacuum systems do work - I just think 4000 MPH is beyond fantasy.
Re:Liability (Score:5, Interesting)
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 (Score:5, Insightful)
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 (Score:5, Informative)
Won't be under an hour, unless we're pulling .2g or so.
More like 80-90 minutes.
Your point stands, however - it would make a bloody mint if it existed. If only from people who rode it just so they could say they did it....
Re:Liability (Score:5, Interesting)
Won't be under an hour, unless we're pulling .2g or so.
More like 80-90 minutes.
Your point stands, however - it would make a bloody mint if it existed. If only from people who rode it just so they could say they did it....
I'm not sure I buy that: Round-trip flights between LA and New York can be had for under $300 and take 7-8 hours, including time at the airport. So what price premium is the public willing to pay to get there in 1/3 the time (assuming it takes some time to get on and off the train)? I have trouble believing the capital costs of a vacu-mag-lev passing through two mountain ranges is going to have a lower per-mile cost than the current California HSR (currently ~$100 billion for ~500 miles, or $200 million / mile).
Do you think you can really charge a big enough price premium to cover the extra capital and operating costs of such a thing? I think the Concorde has your answer.
Re:Liability (Score:4, Informative)
Plus, if it was more convenient and also faster than air travel, more people would use it. One hour from LA to NY would take about the same time as my regular commute into work from the suburbs into the city (a distance of roughly 25 kilometres, in traffic).
Re:Liability (Score:5, Informative)
Well, in fairness, the Big Dig is not a good example considering that 2/3 of the money probably ended up in the hands of criminal syndicates of one sort or another. Also, it was built underground below the water table, and required a tunnel six or eight lanes wide - probably an order of magnitude or two more difficult and expensive than a train-size tunnel.
By comparison the City of Portland, Oregon recently completed the 'Big Pipe' [portlandonline.com] projects, digging about 10 miles of tunnel up to 160 feet underground (and under a river) to handle storm runoff. They used 14-foot diameter boring machines and did the whole project for $1.5 billion, which is about $150 million per mile. That cost included all the pumping stations and other costs, not just boring the hole. (See also West Side CSO Tunnel [wikipedia.org].)
So the cost of drilling a train tunnel, which would fit nicely in a 14 foot diameter tunnel, should be of the same order. Adding maglev or whatnot to make trains actually go would be additional, of course. At $150 million per mile, the 400 miles from SF to LA could be drilled for $60 billion. But you actually need three tunnels - one each way plus a service tunnel (like the Chunnel between UK and France), so call it $180 billion.
Re:Liability (Score:5, Informative)
You don't have to guess about the maglev part, because Japan is building an actual long-distance maglev line [wikipedia.org]. Costs seem to be about $200 million / km, but that includes everything, stations, etc (compare the various route choices and note that the construction costs don't vary nearly as much as the distances [that's affected by the amount of tunneling, etc, too, of course]).
Re: (Score:3)
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First there was never any realistic suggestion of 4000mph, I think he made it up as a premise to write his fluff article.
The story is about as thin on science or facts as your typical comic book.
If you could achieve 400mph that would be sufficient. Nobody has seriously suggested 4000mph land based travel.
400mph tube trains would allow you to have fixed stations supplying the propulsive power, and the mag-lev or air-suspension engineering can easily handle any defects that would affect the ride at that spe
Re:Liability (Score:4, Informative)
The problem we have in the US with high speed trains is our rail system is beat to crap by freight trains, meaning our trains can't go very fast. Other countries tend to use new and separate facilities for passenger and freight. Even Amtrak is starting to gear up for high speed rail [inhabitat.com], but it is dependent on private railroads for track. But laying new track, or improving existing track is far cheaper than building tubes all over the country.
Yet another example of how politics can ruin anything. In order to get the law creating Amtrak through, the politicians agreed to allow the railroads to continue to prioritize their profitable freight over Amtrak. Amtrak trains, except in a few cases, get the lowest priority of anything on the track. And Amtrak has no ability to improve track so their trains can go faster. In many areas they are restricted to 20 MPH due to track conditions, hills, urban conflict, etc.
The right way to do it would have been to nationalize the railbeds (buy them from the railroads) and let the railroads, now stripped to their essential function, compete on service and price. This could have been done back when the railroads were all going bankrupt. Now it's too late. Governments are reasonably good at maintaining infrastructure, businesses are generally better at service, so it would have been a productive arrangement, similar to both airlines vs. airports and trucks vs. highways.
Perhaps.. (Score:3)
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: (Score:3)
Re:Perhaps.. (Score:5, Insightful)
Someday maybe the Japanese can figure out how to build a bullet train in an earthquake zone.
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Re:Perhaps.. (Score:4, Insightful)
The train has a lot of inertia. Those magnets would have to be insanely strong to keep the train in the center if there was a shift in the tunnel.
Either that, or the tunnel would have to be built some percentage larger than the train, so that the train could wander farther from the center of the tunnel without touching the tunnel wall.
Even then, imagine going 4,000mph and then getting shifted say, four inches to the right all of a sudden. You'd have a hard time keeping your internal organs, well, internal.
I don't really see how the forward speed of the train would amplify the effects of lateral shifts. 747s shift four inches to the right every day when there is turbulence, with little damage beyond airsickness. Heck, the Earth is speeding at 67,062 an hour on its journey around the sun, and yet I can shift in my chair as often as I like without losing any internal organs.
Re:Perhaps.. (Score:4, Informative)
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.
Come on AC, don't be a jerk, explain why. The reason why earthquakes don't matter in civilized country with trains is data travels around the speed of light (well, Vp correction factor, but pretty GD fast) and earthquake waves travel at the speed of sound in rocks (well actually compression waves go a different speed that transverse waves but whatever). The point is the ratio is ridiculous. So you have earthquake sensors everywhere including deep in mines and wells and even in worst case scenarios you can get warning minutes before the quake hits the train (no kidding). Now 4000 MPH is faster than sonic so if you're headed away you ignore it, the wave isn't going to hit until long after you arrive at destination. If headed toward, well you got issues, but 4000-0 is not really all that long. A spacecraft like the shuttle never peaked above 3 G but went 0 to 18000 in what 9 minutes or something? So if you're willing to risk 10G I think you can stop pretty darn quick.
Its the same reasoning why satellites save lives in hurricane areas... yes the satellite is much further away than the hurricane, but even so, the radio waves get to the shore long before the hurricane arrives...
Re:Perhaps.. (Score:4, Informative)
Thanks for that. I actually snorted out loud. Trained marines in pressure suits with the force vector compacting the spine are reduced to peering through a constricting black tunnel in their field of vision in the desperate attempt to not black out before the missile passes.
I've heard -3g (e.g. non-inverted power dive) described as having an 800lb gorilla sitting on your shoulders squeezing your head between his thighs as if he's nearing his moment. Pilots rarely try this twice.
If people are facing forward wearing lap belts, they will all be praying to Allah with outstretched hands the size of dinner plates while bleeding from ruptured eyeballs. Roller coasters are limited to about +5g for short duration in optimal seating conditions. The nearest such coaster to my location is the one in West Edmonton Mall.
Not to worry. I'm sure those powerful magnetic fields in evacuated tunnels are magically convex--at least on paper--after a little problem with the Swiss-made magnet contacts is sorted out.
If a train squeaks in an evacuated tunnel, does anyone hear it?
I had forgotten all about Canary Wharf. An ever popular business model: dream big, or go home. These kinds of projects never attract the feeble of heart.
Maybe because... (Score:5, Informative)
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: (Score:3)
The British pneumatic system was somewhat comparable to the steam slings used to launch aircraft on carriers and was inherently leaky.
And that's aside from the crude technology available 1-1/2 centuries ago.
As a matter of fact there is no comparison.
Re:Maybe because... (Score:4, Funny)
Mach 10 Train Arrives At Station, All Passengers Dead From Exposure To Vacuum
Re:Maybe because... (Score:4, Informative)
To put that in perspective, the first notable "flying machine" was invented 50 years after that. Yet we managed to put a man on the moon 69 years after, and 100 years after the sky is filled with airplane carrying passenger with safety record that rival all the other type of transportation.
Re:Maybe because... (Score:4, Funny)
Re: (Score:3)
How long would it take for workers to actually travel to the middle of a tunnel to get said leaks fixed?
Not only do you not need to limit yourself to one (or two) holes, its actually better to drill as many as possible. This is as true in mine and tunnel engineering as it is true in pr0n.
Safety is not an issue (Score:5, Insightful)
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 .. (Score:5, Informative)
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 .. (Score:4, Insightful)
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.
Consider the Large Hadron Collider. It doesn't have significant volume compared to a piece of the tube train track discussed in the article, but they have figured how to maintain vacuum over a 17 mile long tubular ring. And the quality of vacuum in the LHC would be better.
kinetic energy (Score:4, Insightful)
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 (Score:5, Informative)
Vacuum-Tube Trains (Score:5, Funny)
They do have a warmer more 'natural' sound
Re: (Score:3)
But you have to sit in the station for a while after the doors close, while the cathodes warm up....
Why the exagerated speed? (Score:4, Insightful)
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: (Score:3)
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 (Score:3)
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.
Fire - Catastrophic Fire Risk ... (Score:4, Informative)
The reason the vacuum systems went out of favor was the massive associated fire risk. At first, it doesn't seem obvious why a vacuum system would have a fire risk, as in theory the vacuum should extinguish the fire. However, this doesn't work in practice.
What actually happens is the fire starts outside the vacuum system, where it has access to air. The fire then causes this air to expand. The logical place to expand is straight into the nearest low or negative pressure environment around, which is the vacuum system. In no time at all, the vacuum transportation system spreads the fire between floors - and disaster ensues.
Vacuum transportation systems used to be popular in multilevel buildings of large companies. Then one by one they caught fire. Eventually, the fire codes understood the significance of plenums and air return systems in spreading fires. Now any kind of vacuum, plenum, or return air space that stretches between floors has special safety devices inside it. They are extremely dangerous spaces if fires occur.
Additionally, vacuum systems were never used to transport people, because if air integrity on the capsule fails, then everyone suffocates.
The trouble with tunnels (Score:3)
There's been enthusiasm for underground tunnels in science fiction since at least the 1920s. Tunnels, though, are hard to build. Read a few issues of "Tunnels and Tunneling" to get a sense of the problems.
Solid ground isn't really that solid. Tunnel projects encounter sand, silt, water, oil, natural gas, shale, coal, and salt. Each requires different techniques, and most can't support an open in space in them. Tunneling often involves building a structure able to hold the tunnel bore open. Support rings, props, rock bolts, shotcrete, and steel are used when necessary. A single long tunnel job may encounter all of those.
As a construction project, a tunnel has a major logistical problem - most of the work is at the cutting face. So there's not much parallelism. Major tunnels are bored from both ends. In some cases, shafts are dug to intermediate points to allow advancing from multiple locations.
That option is possible on land, but slow and expensive for deep tunnels. It was used for the 57km Gotthard Base Tunnel, and required digging two access shafts around a kilometer long. That job took 14 years of tunneling.
Underwater tunnel projects are usually limited to working from both ends. In a few cases, existing islands, or even artificial ones, have been used to gain access points. The Tokyo Bay Aqua-Line has an artificial island.
Large tunnel projects today seem to run about US$0.2bn to $1bn/kilometer. It's much more expensive in urban areas or earthquake-prone areas. Hard rock tunnel projects are slow, but not overly expensive. Tunnels in difficult ground get very expensive.
It's a no-go (Score:4, Interesting)
I thought of the idea a while back, and I'm sure plenty of other people have too. It's really cool in a way, but I doubt it would ever be practical. The main problems I thought of:
Cost. It would have to be ungodly expensive by any measure, both to build and to operate. Could there ever be enough people willing to pay enough money to get, say, from NY to LA, faster than anything else to justify it? And it isn't very flexible either compared to air travel. If some other part of, say, NY, gets much more popular, then you can just build a new airport and reroute flights as needed. If you're using these giant vacuum tubes, you'd have to re-drill half of the run.
How tough it is to keep the tube in vacuum? We don't have any good way to estimate that now. Might need several high-grade vacuum pumps per mile that draw lots of power. It's pretty single-point-of-failure too - any significant air leak anywhere on the entire run, and any trains going fast enough to make such a system worth the trouble would probably be completely destroyed. It isn't just an air-resistance problem - unless the tube is much, much bigger than the train, then all of that air would be forced through the relatively small area between the train and the tube, thus much higher pressure spikes that would probably compromise any structure, and once you get the first crack, the whole thing will disintegrate real quick under the 6k MPH winds, leaving everything and everyone in the train as a stain on the walls over the course of a few hundred miles.
Handling sounds tough too. Like loading, unloading, servicing, turning them around, etc. You'd need lots of really good pressure seals that will stand up to many thousands of cycles with passengers doing all sorts of wacky things to them, and lots of elaborate procedures carefully followed. Getting trains into pressure for service (or do we have service techs in space suits?), loading and unloading passengers and cargo though some kind of airlock/jetbridge thing. Make a mistake anywhere, and you either pressurize the tube, destroying any trains travelling in it at the time, or suffocate all of the passengers in a train. Hope you never have a train break down in the middle of the line either.
Swissmetro (Score:4, Informative)
A concept like this has be studied since 1970 in Switzerland. The subject was more warm in the early 1990, with an idea of real experimentation, but cooled down when faced the complexity of the project and his hazardous profitability. There is still some trace of it on the web:
http://en.wikipedia.org/wiki/Swissmetro
http://www.swissmetro.ch/en/home
Re:Simple (Score:5, Insightful)
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 (Score:5, Insightful)
The point is things like planes weren't possible until gasoline engines, very quickly powered flight went from impossible to possible due to one technology and some smart people.
So:
1. Don't stop dreaming
2. Your Religion of Pessimism is just as bad, so STFU
Re:Simple (Score:4, Interesting)
You do realize that this article is about _trains_, right? You and your monomania are what brought space into the discussion. There's nothing impossible about a maglev train, nor a superconducting power cable, nor a depressurized tunnel. We already have all of these things. It may prove cost prohibitive to operate a train system like this.
Frankly, all that the article could really has to say about why such trains aren't being built is that they might be hard to maintain and everyone will die if it crashes. That and some completely hyperbolic speculation about one little leak almost immediately compromising the entire vacuum. So, basically, wow. Super-informative article. No really.
Re:Simple (Score:4, Insightful)
Unless you *find* the energy source, all you have is DREAMS. ... our energy base for the entire planet is decayed plant matter
Wait, where did all the nuclear reactors go?
Re:Simple (Score:5, Informative)
You guys always point to reality...as a defense for your delirious mental illness about space. Doesn't work that way.
Ummm...yeah. What do you want people to point to instead? The Starship Enterprise? That's kind of the the point. You say that ${futuristicConcept} can't be done because of insurmountable technical obstacles. Other people point to ${formerFuturisticConceptThatIsNowReality} as a counter-example of something once thought impossible, but now taken for granted. For years, people said it was impossible to fly in a heavier-than-air, powered aircraft...then our friends Wilbur and Orville (or Glen Curtiss, depending upon who's revisionist history you choose to subscribe) did it. People thought that rockets couldn't "fly" in a vacuum because there was "nothing to push against." Then the Russians launched Sputnik. All (or at least "many") experts said we will never exceed the speed of sound...then Gen. Yeager did it. The point of all of these examples is that people thought a number of various things were impossible...until someone figured out a way to get around the obstacles that people thought were "insurmountable." Griping that pointing "to reality" to argue that things are only impossible until someone accomplishes those things is, in fact, the way it works.
Those things were built because they were able to build them...
True statement is true, yes. Your point?
What you are blatantly ignoring is that people didn't think those things were possible -- exactly as you don't think various things are possible now. The problem wasn't that things were intrinsically impossible; it's that people were approaching the problem from pre-conceived notions based upon the limitations of existing technology. In what way are the things you currently say are impossible merely limited by our current understanding of physics? This may come as a shock to you, but...(wait for it)...we don't know EVERYTHING yet. Therefore, we can't predict what "impossible" things will become possible when some "Eureka!!!" moment shows that something we all thought we understood gets shattered wide open by a new discovery. When we get that insight, things that we thought were impossible might suddenly become trivial.
Re:Simple (Score:4, Insightful)
There is a small, but important difference between daydreaming and actually setting out to make something real with the technologies you have at your disposal. In the first case, you get the starship Enterprise movie. In the second case, you get the space shuttle Enterprise.
People were daydreaming about flying around for ages. Around the end of the 19th century, a whole body of junk science about how airplanes were supposed to fly had developed, resulting in a lot of money and effort wasted in unsuccessful airplane projects.
Alas, flight did not happen until the Wright brothers built a testing rig, threw out all the junk theories and designed something that could use technologies available at the time to actually take off.
Eureka doesn't simply happen from staring at your navel for many days.
Re:Simple (Score:4, Interesting)
If there were no one daydreaming about the possibilities, no one would attempt the impossible. Thus it seems to me that the starship Enterprise is a necessary step towards achieving the space shuttle Enterprise, even as the space shuttle Enterprise is merely a rung on the evolutionary ladder to the starship Enterprise (there's a recursive conundrum for you, lol!).
Furthermore, compared to a lot of the other attempts at powered, manned, heavier-than-air flight, the Wrights followed a much more rigorous, evolutionary process towards their goals, which is one of the biggest differences between them and their predecessors (as well as many of their contemporaries). However, if you think that they threw out all of the thinking about flight that came before them, you are very much mistaken. Man had flown before Wilbur and Orville, even in heavier-than-air aircraft. Google Otto Lilienthal for an example (hint: what's the biggest, most obvious difference between a Cessna and a Blanik?). The Wrights took the collected knowledge of their day, tested numerous theories, and, as you said, "threw out all the junk" -- but they KEPT a lot of things, too. They had two big breakthroughs that had eluded others: first, they understood that for powered, sustained flight, you don't want the aircraft to be too stable because stable and controllable are diametrically opposed; second, they understood that turning an aircraft required redirecting part of the lift vector in a horizontal direction (i.e., turning requires banking rather than yawing). Basically, they were *excellent* examples of putting the scientific method into practice: observe, hypothesize, test, wash, rinse, repeat, and then take the one additional step that separates a scientist from an inventor, namely, build a practical device that makes use of the results of experimentation.
No, "Eureka!" doesn't happen from simply staring at your navel, but then again, I don't remember claiming otherwise. I merely pointed out that oftentimes, "Eureka!" is the result of approaching a problem from a different perspective. The "insurmountable" obstacles often aren't. They just require technology or knowledge that didn't exist earlier (wing warping, unstable airframes, and strong-enough-but-light-enough powerplants, in the Wright Brothers example or understanding that it is the equal and opposite reaction rather than exhaust gases pushing against the atmosphere in the rocket-in-a-vacuum example I mentioned earlier).
Re:Simple (Score:4, Interesting)
For example, you seem to have a pet peeve about ever colonizing space. I agree that with our current state-of-the-art, it won't happen. Chemical rockets can't achieve the kinds of velocities that are necessary to cross the vast distances between earth and even the nearest of stars (excluding the sun, of course). Einstein predicted that even an infinitely powerful engine wouldn't even be able to do so, due to the limiting factor of c. Consequently, yep, the outlook for colonizing space looks pretty bleak from here at the beginning of the 21st century. But neither you nor I know what kind of breakthroughs in physics are going to happen in the next hundred, thousand or even ten thousand years, any more than a Roman Centurion could have imagined the Internet or nuclear fission. It's probably safe to say that there won't be a physics breakthrough that allows us to actually accelerate a mass faster than the speed of light...but is there a way to avoid that limitation altogether? Will we figure something out that lets us sidestep the speed of light as a limiting factor? We don't know. Therefore, I take exception when people like yourself say something like space travel will "never" be possible. Never, as I am fond of telling my daughter, is a really long time. It's certainly a lot longer into the future than you or I will ever be able to see.
Re:Simple (Score:5, Insightful)
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 (Score:5, Interesting)
Re:Simple (Score:5, Insightful)
Trains are an economic bonanza in the US. Freight trains are still trains.
Limit your comments to passenger trains, and you might think it is true. Then you realize they're competition g with heavily subsidized highways.
Re:Simple (Score:4, Insightful)
Amtrak. US passenger train service is owned by the US Government and is MASSIVELY subsidized.
Americans only like looking at trains and thinking to themselves "If it were more like my car I would love to ride a train."
Trains do not work in the US because of who Americans are.
Re:Simple (Score:4, Interesting)
Trains do not work in the US because of what the US is.
Europeans always forget how incredibly tiny their nations are and how incredibly big the US is. Our population isn't bunched up into a few mega cities like yours is either and there is no reason it should have to be. Some people consider privacy to be more important than the infrastructure advantages in everyone being close together.
Suppose you built a high speed rail between LA and New York. Its fast, 200mph. So it can (ideally) cross the 2378.8 miles in a little under 12hrs if it makes no stops. Wonderful, its faster than I could drive it. But how now that I'm in new york, how do I get to the store that is 5 miles away from the station? Now that I am there, how do I get the shopping cart full of goods back to the train? Do I purchase another couple seats to store it? Will the train wait while I load and unload it? How do I get it to my home in a small town 50 miles from the station? What if my purchase included a piece of plywood and four 3m lengths of pvc for some basic work around the house? And if like many I do that every 3 days?
In the EU you might be considered extremely rural if you live 100km from the nearest reasonable point for a passenger station but it would be considered the suburbs here in the US. You'd have to go quite a bit further to reach rural.
Re:Simple (Score:5, Informative)
When folks talk about Amtrak, one of the first comments is that it is subsidized. It is, to the tune of 2.6B a year at the current moment.
We spend approximately $150B a year in state and federal money on highway construction and maintenance.
We spend approximately $16B a year operating the FAA and airports, about 3.5B of which is directly spent on facilities construction and maintenance.
All transportation is subsidized. Cost per passenger mile, cost per trip, or other similar metrics are a far better measurement of financial performance. Passenger fairs are also a very interesting thing to look at, if the same subsidy for rail and airports resulted in fares that were 50% less for rail travelers that may be a better subsidy.
The problem in the US with rail is really simple to boil down. Congress mandates Amtrak serve underserved and out of the way communities. Greenwood Mississippi has Amtrak service because the government said they must go there, not because it is the best route, or the most profitable one. At the same time Congress wants Amtrak to be profitable. That's a combo that doesn't work. It could be a profitable service by aligning routes with where people wanted to go, and dumping unprofitable ones. It could serve underserved communities with a subsidy. It can't do both at the same time.
High speed rail is a long term investment problem in the US, and a problem of our red-tape with building things. The transcontinental railroad was built in 6 years, largely with hand labor. California's high speed line is estimated to connect San Francisco to LA by 2030, 18 years from now. Much of this is the ever evil "regulation", however much of that derided regulation is stuff the people voted for in the first place so we don't destroy our environment, and so on. Much of it is time taken up with legal challenges, large and small, wasting time and money in court. We have to take a hard look at this sort of problem, the US is now building infrastructure at a much slower rate than most other western countries, and that's not a way to stay ahead. We can't just throw out the regulations, that will not leave a functioning society, but we need to streamline many of these processes.
Trains can work just fine in the US, and they do in fact operate profitably in several locations today.
Re:Simple (Score:4, Insightful)
Such things are better run as cost centres. They must meet targets like safety, efficiency, availability, reliability, coverage, etc but I don't see why they must be profitable. If after the other targets are met and they are still profitable, that's icing on the cake.
Re:Simple (Score:5, Insightful)
Trains work in the US when shipping freight. The work for passengers in the northeast. However, cars are far more convenient everywhere else.
Case study:
Trip to Norfolk, VA from NYC area.
Fly: ~$300 per person round trip. You get one carry-on bag per person. 1.5 hrs each way + 4 hrs of transit/wait time.
Train: ~$250 per person round trip. You can carry more on. 8 hrs each way + 2 hrs of transit/wait time.
Car: ~$75 per car round trip. You can carry even more. 6 hrs each way; no wait time.
Now, if I didn't already have a car with sunken capital costs, then there is an argument. But even then, I would rent a car. Either way, it is cheaper and takes less time to drive than take the train.
In contrast, it would be crazy to drive into NYC when the train station is right next to where I am. Flight is almost always better if time is a factor.
And don't tell me "it's different in Europe". I was in Germany. I can drive from Munich to Berlin faster than the ICE train. And the train ride costs $150+ each way per person.
Outside of heavily subsidized metro area trains, I have not seen a train compete with the cost, let alone the time and convenience of driving alone. When you add a 2nd person, it just gets crazy to take a train.
Re: (Score:3)
Trip to Norfolk, VA from NYC area.
Fly: ~$300 per person round trip. You get one carry-on bag per person. 1.5 hrs each way + 4 hrs of transit/wait time.
Train: ~$250 per person round trip. You can carry more on. 8 hrs each way + 2 hrs of transit/wait time.
Car: ~$75 per car round trip. You can carry even more. 6 hrs each way; no wait time.
By "NYC area", you mean "an hour south of New York City", right, since it's at least a 7-hour drive from within the city to Norfolk. Yes, you can drive faster than the speed limit (which is what MapQuest and Google use in their 7+ hour calculations), but you need to drive a lot faster to make up for the traffic you will likely hit unless you drive at night.
Re:Simple (Score:5, Informative)
If you planned ahead, and had the relevant travel card, that price goes down to EUR79 (USD100).
That journey is a little over 6.5 hours on the train. You'd be lucky to do it under 6 hours driving, factoring in relevant breaks and depending on where in each city your arrival and departure point was. If I had anything to do at the other end, I know I'd much rather travel by train than bust my butt driving.
I regularly catch a tran from Vienna to Graz in Austria. The cost is around EUR18 one way, with discount card. The journey takes 2.5 hours by train, and maybe 2 hours by car, depending on the traffic. On the train I can read, work on my laptop, sleep, walk around, go to the dining car etc. It's a much more pleasant way to travel.
Re:Simple (Score:4, Insightful)
Throw enough ridiculously cheap fuel at them (and comparisons that ignore the cost of ownership), and almost anything looks worse than an automobile.
Re: (Score:3)
Re:Simple (Score:5, Informative)
And don't tell me "it's different in Europe". I was in Germany. I can drive from Munich to Berlin faster than the ICE train. And the train ride costs $150+ each way per person.
Berlin-Munich costs 44 Euros each way (you have to buy the ticket a few weeks in advance though), and takes 6 hours. Driving takes the same amount of time, and will cost you at least 50 Euros in gas (600 km * 5l/100km * 1.65 Eu/l = 49.5 ~ and that's a pretty efficient vehicle - you won't get that efficiency doing 160 on the autobahn). So you're just plain wrong. Not to mention, many routes are much faster than a car; Frankfurt - Gottingen takes 1h40m on the ICE and 2h30m by car.
You can't look at the "in station" ticket prices, that's just ridiculous... have you looked at the price of airplane tickets if you buy them at the airport??
Re:Simple (Score:5, Informative)
Trains only work when government subsidizes them. FOR the cost of the new California High Speed Rail, that won't actually be useful until just before it is completed (i.e. nobody could ride it anywhere useful), you could give every man, woman and child a whole bunch of passes on Airlines from more places in the state than the CA HSR would actually go. And it would take less time to travel to said places. And cheaper.
The way I explain it, we already have HSR, they are called Airplanes. HSR was designed for one thing only, to curry favor with the Unions that will build and run them. It is a Union Make Work Program .
Here's the math ...
Cost of the HSR system (current est) 65,400,000,000 (this is nearly 50% more than the ballot said it would be) It will be much higher when all is said and done.
Actual Population of California 38,000,000
Short versions of the numbers 65,400 / 38 = $1721 per man/woman/child
Cost of a plane ticket $68-$250 one way. That is SEVEN free (high cost) tickets per man woman and child in CA. THIS does not count the actual cost of the ticket to ride the train. And all the projections, even from the Rail Authority, tell us that the cost will have to be continually underwritten by the tax payers.
I have yet to have a person make any sort of reasonable argument why we should spend that kind of money in a state that is going broke.
Re: (Score:3)
OK, but what about AFTER the train would be complete? You have to keep spending those costs for your flight voucher system to work. Once the train is built it becomes cheaper.
Re: (Score:3, Interesting)
You're assuming that there is no other way to spend the money on infrastructure that would have more benefits. How about adding a dozen more regional airports? Same effect, only doesn't cost tax payers on an ongoing basis.
Re:Space Elevator (Score:5, Informative)
Vertical travel is a very different proposition. Compare the energy usage for a person standing at the top of the Empire State Building and a person standing in a helicopter hovering a few metres away. Both are at the same height, but one is having to use fuel (in quite significant amounts) just to stay in the same place. Now have the man in the building go up and down the stairs for an hour and have the helicopter maintain the same height as him. At the end, compare their energy usage.
In contrast, for something like a train the majority of the energy is used in acceleration. Reducing air resistance and rolling resistance give some benefits, but it's not huge. The advantage of the hypothetical maglev vacuum train is that it can keep accelerating for as long as it wants (air resistance increases with speed). This isn't really useful for most trains, although it would be useful for something like a transatlantic or transpacific railway where you'd have a long distance and nowhere where you might want to stop on the way.
For reaching orbit, a space elevator means you don't need to carry as much fuel. Over 90% of the mass of a rocket going into orbit is the fuel required to carry the fuel into orbit. Take that away, and you've made a huge saving. If you can power the climber from the ground, it's even better. Acceleration is also an issue. A rocket must accelerate at more than 1g just to move upwards. Because of this, it must accelerate hard so that it doesn't run out of fuel just maintaining the 1g needed to stay in the same place. A climber can maintain a constant speed or a slow acceleration.
The main reason we haven't built a space elevator is that we've only recently made materials in the lab that are (probably) strong enough to be used for the tether, if we could work out how to mass produce them.
Re:Simple (Score:5, Insightful)
Airlocks? Docking a train in a near-vacuum tunnel to a station has to be considerably easier than docking two spacecraft in a vacuum.
Re:Simple (Score:5, Interesting)
First, airlocks used in space are used a few dozen times at most before being completely overhauled. The docking connector on a train like this would get more than that much use in a single day, probably in a single morning.
If you're thinking of airlocks, then you'd have to depressurise and repressurise the train at every station. If you actually mean a tube connected to equal pressures outside of the tube and inside the train, then you're assuming that the seal of something that can be attached and detached, can handle one side moving as the train bounces up and down slightly as people step on and off, and still will have zero leakage.
Re:Simple (Score:5, Funny)
Have you ever heard of airlocks?
Re:The only answer for the USA (Score:4, Insightful)
Re:The only answer for the USA (Score:5, Insightful)
Not necessarily. Bear in mind that when you're talking about accelerating to 4,000 MPH, you're limited to very-long-distance travel. Bear in mind, we're talking about Los Angeles to New York City in a little over half an hour. This wouldn't replace subways, but rather would replace jets and trains.
Also, when public transit is used by people who can afford cars, it is usually because driving is unholy in those cities. It would be more precise to say that public transit doesn't work unless the normal road system is hopelessly broken, which is not the case in the suburbs.
Re:The only answer for the USA (Score:4, Informative)
Re: (Score:3)
Re:The only answer for the USA (Score:5, Funny)
It's the mile-low club.
Re:The only answer for the USA (Score:5, Funny)
It's the mile-low club.
Technically its the "mile per second club".
MPH (Score:4, Funny)
"Miles per hobo".
Re: (Score:3)
Are you sure you don't understand why a decentralized "pod" system wouldn't work?
Re:The only answer for the USA (Score:5, Interesting)
*So every Friday, four GS guys who always sat in the same spot, would have beers on the train. One of the guys retired, and they need a fourth to occupy the seats -- they didn't want some random person sitting with them. They asked me to sit with them, it lasted about two months until circumstances made it better for me to commute by bus instead of train. These guys would pound a beer (or two) in Penn Station waiting for their train, then drink another one (or two) on the 40-minute train ride home... they jokingly said it was the ammunition they needed to deal with their wives for an entire weekend.
But I digress...
If you take the Morris & Essex express into Hoboken or NY, which skips all or almost all the stops in Essex county, you'd believe that it's only the *wealthy* who take trains.
Re:Why? (Score:4, Funny)
Re:Why? (Score:5, Funny)
vacuum trains?! (Score:5, Funny)
Re:Why? (Score:5, Insightful)
Re: (Score:3)
Re:Why? (Score:4, Informative)
Re:Why? (Score:4, Informative)
one word: VACUUM.
Two words: fire triangle
Two words containing a difficult one: fire tetrahedron
Before one will burst into flames one needs oxygen first. In a vacuum there is no hazard of bursting into flames. Remember this, and when you get your first physics lesson on combustion at school you will be mister smartypants!
If there is no oxygen, how on earth do you think the occupants of that vehicle are going to breath? You bet that such a train will need to carry oxygen, one way or the other. And in the event of a crash, that oxygen could be released into the vacuum, and there is your fire triangle, complete.
Re:Ultra-efficient first post (Score:5, Funny)
I'm not half as think as you drunk I am.
Re:Related questions... (Score:4, Funny)
Two for Fido.
Re: (Score:3, Insightful)
Re: (Score:3)
The military has already invented caffeinated bacon, and you can get baconated coffee at select retail outlets.
Just be patient. The futurama will happen eventually.
Re:Tube to spaceballs (Score:3)
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:in the year 3000 (Score:4, Informative)
hopefully the passenger dispersal method will be safer than just dumping us on the curb
Re: (Score:3)
Re: (Score:3)
Re: (Score:3)
Re: (Score:3)
Re: (Score:3)
At one g it's 3 minutes, 2 seconds, I believe. (Using Wolfram Alpha 4000 mph / 1 g acceleration).
Re: (Score:3)
Stopping the capsules when loss of power occurs is just a matter of simple friction brakes like on high speed elevators.
And what makes you think we can't fly over the North Pole???