Ask Slashdot: What Would Happen If a Hyperloop Train Failed? 736
dryriver writes: I've been following Elon Musk's Hyperloop initiative with great interest. The idea of getting from one city to another at 700 MPH without having to suffer through an airport and all that jazz is revolutionary. I'm glad that somebody is trying to innovate in the area of land travel. My question though: When conventional trains going at much slower speeds derail or crash, the result is often serious injuries or deaths. What happens if something goes wrong with a 700 MPH Hyperloop train/pod or with part of the track? Would a Hyperloop accident at that speed even be survivable?
That's easy, it would get a participation trophy (Score:4, Funny)
This is the 21st century you white cisgendered Trumpist-pig.
There's no such thing as "failure" and the HyperLoop would simply get a participation trophy and be placed in the protected trans-functional class where you can't criticize it.
Re: That's easy, it would get a participation trop (Score:3, Funny)
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If the vacuum is breached behind the train, it might accelerate first then crash and stop.
Because air pressure behind and less pressure in front, for a while.
To prevent this, you might want an automated emergency system to vent in front of a train (increase pressure there) if pressure is increasing at back of it.
simple (Score:5, Informative)
Even More Simple (Score:5, Insightful)
We don't know what will happen because it hasn't been engineered and built yet. Determining how it handles various types of failures will certainly be part of the engineering process. Worst case scenario is everyone dies, which isn't much different than a plane crash. But just like with a plane, plenty of fail safes will be there to allow for managed failures. Most catastrophic failures will probably just cause the train to come to a gradual halt.
Re:Even More Simple (Score:5, Interesting)
Re:Even More Simple (Score:5, Insightful)
A containment failure doesn't need to implode - it can just leak. Depends on the materials and the details of the design. And if it leaks, then everything slows down and stops.
I can't imagine they'd build this thing without any sort of safe failure mode.
Re:Even More Simple (Score:5, Insightful)
What do you mean by a containment failure? The tube is going to have a near vacuum in it so it has to be built to withstand a pressure difference of only one atmosphere. That's like a submarine diving to 10 metres. I think we can manage that.
I think it's much more likely that the tube will develop a leak. When a train traveling at 700 mph hits the air, it's going to slow down, probably quite rapidly. I couldn't begin to tell you how that will pan out. It may be that it is not a big deal because there probably won't be a wall of air so much as a pressure gradient.
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That's like a submarine diving to 10 metres
A submarine that is hundreds of miles long. One that is subject to seismic movement in up to three directions.
But there is more to it than that. How about a piece of debris falling off the train and either smashing along the side between it and the tunnel wall. Or hitting the next train that uses the tunnel?
The big difference between perceived danger in air travel and car travel is one of control. Cars can at least try to avoid accidents. Planes, less so. With a hyperloop that Musk himself says can take
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Do we really know what the deceleration would be? Is the train supposed to fit the tube perfectly like a piston in a cylinder, or is there a gap? If there's a gap it might not be so bad. Even if it's like a piston, air is highly compressible and there could be blow-out gaskets. Under ordinary circumstances the outside air will push the gaskets in hard. Just put a few plates with relatively weak bolts and some caulking at regular intervals. Under ordinary circumstances even the strongest man couldn't p
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How is a 'containment failure' going to cause the line to implode?
Re:Even More Simple (Score:5, Funny)
Maybe he thinks the hyperloop walls are made of the same material as party balloons.
Re:Even More Simple (Score:5, Insightful)
Tanker cars are designed to keep the contents inside, not contain a vacuum. The forces are literally the opposite of what was designed. You might as well claim that the pyramids are a poor design because they'd fly apart if turned on their side.
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I don't think it's feasible at all from an economic standpoint, but some of the criticisms are from people who watched a YouTube video or something and are not that well thought through. There's not a lot of impossible physics being proposed - just very expensive engineering that, IMHO, is doomed to be too costly and too complex (and thus unreliable) for practical use. Holding vacuum economically is a huge challenge - tubes crinkling up is not.
Re:Even More Simple (Score:5, Insightful)
There is not 'a lot more pressure' outside than inside. IF they managed to create a perfect vacuum, the pressure difference would be about 15PSI. There are tons of materials that can handle that puny pressure difference. For comparison, natural gas is pumped through pipelines at about 250PSI. A leak does not cause a catastophic failure of the pipeline.
Re: Even More Simple (Score:3)
Just remember that not every major incident ends a fatal crash. Check out Air Transat 236, which ran out of fuel over the Atlantic. The pilot even managed a 360 degree turn without hydraulic power to control the altitude as he glided it back to the Azores.
https://en.m.wikipedia.org/wik... [wikipedia.org]
Ok, pretty exceptional!
Re: Even More Simple (Score:4, Interesting)
To bleed altitude. Commercial airliners make terrible gliders, but still, they technically are gliders when the engines are no longer operational. In this case, the airplane glided to the Azores but had too much altitude and needed to stay in the air a little bit longer while not moving too far away: a perfect use case for flying in a circle.
Re:Even More Simple (Score:5, Informative)
Do you know how much kinetic energy a moving trainset has at 200mph, let alone 700mph? If there is an accident, that energy has to go somewhere, and wherever it goes, it will have the potential to do something that will kill people.
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However, there are other possibilities, critically dependent on the size and number of leaks, the speed of the vehicle at the time, and how close the leaks are to the vehicle.
If the leak happens on one side of the vehicle, while it is passing - eg because the vibration caused by the vehicle passing is "the last straw that breaks the camel's back" then the vehicle wil
Re:Even More Simple (Score:5, Interesting)
An airplane can glide quite some distance without power. It can even be controlled during this phase.
If a hyperloop tube suffers a catastrophic breach, think of the pressure wave of air rushing in and what that will do to any near by vehicle. Now, what happens to the vehicles in front of the one that just became a bullet in a gun?
Re:Even More Simple (Score:5, Informative)
think of the pressure wave of air rushing in and what that will do to any near by vehicle
There are engineering solutions to that - the most obvious would be emergency vents that open up in the event that pressure is lost in any part of the tube. You can also make the tube larger than it needs to be to let air circulate around the car (like in a regular subway) rather than pushing it like a piston through a tight cylinder. Even a total vacuum is only 1 atm, 14lbs sq in, or 100 kPa lower than ambient - so it's not like we're developing pressures beyond what large brakes could not overcome.
My critique is that the engineering solutions are all going to be complex, expensive and make the thing a white elephant - but it's completely feasible from a technical standpoint.
Re:Even More Simple (Score:5, Insightful)
Unless you actually blow up the tube, you won't get a "wall of air" like that. Not with any real pressure behind it anyway. (for comparison Martian winds are routinely several hundred miles per hour, and they hit with the force of a light breeze because there's not enough pressure to give them any momentum.)
And if you're blowing up the tube, then you'll probably want to wait until a car's far too close to stop and slams into the wreckage at 700mph, so there's not much point in worrying about it. A terrorist attack killing a couple dozen people is trivially easy to pull off and basically impossible to defend against - every corner coffee shop offers a target that size, and is a lot easier to take out.
For anything less severe, you stop - 700mph= 313m/s. 3 to 10g's of braking is eminently survivable, though some injuries may occur. And at 30-100m/s^2 it only takes 3-10 seconds to stop. You'll still travel a goodly portion of a kilometer in that time, but you're not actually going to get a lot of air through the leak that quickly either. And if you somehow *do* have a huge column of dense air rushing at you, can also open emergency hatches between you and it - you'll get buffeted a bit by the closer air that hasn't had time to build up speed, and the first air column will plow into a long column of slower-moving air, dissipating the energy far more gracefully as fresh jets of pressurized air out the emergency hatches.
Re:Even More Simple (Score:4, Informative)
If a hyperloop tube suffers a catastrophic breach, think of the pressure wave of air rushing in and what that will do to any near by vehicle.
A lot less than you'd think. The incoming air (in a worst-case breach) will be traveling at about the speed of sound, so with the train traveling at ~700mph, it'll be like a ~1400mph headwind for a half-second or so. Aerodynamic craft like airplanes can handle that easily, and I see little reason the hyperloop (which will also likely be aerodynamic, for technical reason) would be much different. It'll also be fairly heavy, which means a lot of inertia, so the brief pressure wave won't have much effect on the train's speed, either. After that, it'll just be traveling into a regular atmospheric headwind, which without propulsion will result in fairly rapid, but gradual, slowing to a halt, so no danger there. And that's a massive worst-case breach, where an entire section of vacuum tube completely vanishes. Sort of a large explosion, that'll never happen (and if you have access to a significant quantity of explosives there are much, much easier and more devastating targets to hit).
Re:Even More Simple (Score:5, Insightful)
Huh? The pressure difference, if they manage to make a perfect vacuum, is 1 atmosphere, about 15PSI. Pretty sure regular old steel can handle that. Natural gas in pumped through pipelines at about 250PSI, and a leak does not cause the entire pipeline to catastrophically fail.
Re:Even More Simple (Score:5, Informative)
Vacuum expansion joints are a thing. In those scenarios that awesome* force of vacuum gets contained by .... a small flexible polymer.
*Vacuum isn't an awesome force.
Re:Even More Simple (Score:4, Funny)
*Vacuum isn't an awesome force.
My ZPD says otherwise.
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Plane crashes are seldom fatal (Score:5, Informative)
Worst case scenario is everyone dies, which isn't much different than a plane crash.
Evidently you aren't aware that 95.7% of surviving an accident in a plane. The vast majority of people actually do survive. When the National Transportation Safety Board studied accidents between 1983 and 2000 involving 53,487 passengers, they found that 51,207 survived. [huffingtonpost.com]
It's unclear what the statistics might be for hyperloop but assuming instant fiery death is probably not going to be correct for the majority of failure modes.
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Worst case scenario is everyone dies, which isn't much different than a plane crash.
Evidently you aren't aware that 95.7% of surviving an accident in a plane.
What part of my post makes you think I'm not aware how safe plan travel is? I said the worst case scenario is everyone dies, which is absolutely true of plane crashes. I also went on to say that planes have plenty of fail safes which allow for managed failures. Did you read my whole post? The entire point was that planes are just as inherently dangerous as the Hyperloop but don't end up being very dangerous in practice because of good engineering and operations.
Re:Plane crashes are seldom fatal (Score:5, Insightful)
The mortality rate for national newsworthy and international newsworthy airplane accidents is near 100%, hence the cognitive disconnect.
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We don't know what will happen because it hasn't been engineered and built yet. Determining how it handles various types of failures will certainly be part of the engineering process. Worst case scenario is everyone dies, which isn't much different than a plane crash. But just like with a plane, plenty of fail safes will be there to allow for managed failures. Most catastrophic failures will probably just cause the train to come to a gradual halt.
Even though I agree that scenario could be similar to a plane crashes, I still agree with the parent. The reason is that it takes quite some times (decades) even for the plane to be as safe as now. Until we have figured out most of the issues that may occur with hyperloop technology, most likely many (if not all who ride it) people will die a long the process. Thus, there is no if, and, or but until then.
Re:Even More Simple (Score:5, Insightful)
There's a notable difference to plane crashes though: failures of the tube or even a singular capsule will halt all traffic on the route, potentially for an extended period of time if pressurisation of tube tube fails due to the tube itself being damaged.
Re:Even More Simple (Score:5, Insightful)
If the largest concern in a failure is "people will be delayed" instead of "people will die", I think that's a pretty successful disaster mitigation strategy.
Sabotage (Score:5, Insightful)
Perhaps a more salient question is sabotage.
Explosive charges attached to the tube that detonated five seconds before the arrival of a pod would likely kill everyone on board.
Re:Sabotage (Score:4, Interesting)
An explosive charge on an aircraft or train (or runway or train track) would also likely have a similar effect.
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Re:Sabotage (Score:4, Insightful)
So you've reduced the problem to "no worse than the risks of train tracks, except probably lower fatality count on the hyperloop than derailing a train"
Re:Even More Simple (Score:5, Interesting)
The problem is trains moving at high speed tends to do bad things when they hit a stationary solid object. The Eschede derailment [wikipedia.org] probably would've only had a dozen or so fatalities due to losing a wheel at 200 kph. In fact, the wheel failure was in the first car, but the engine and first four cars survived relatively intact, scraping the bridge supports but coasting to a stop or derailing and hitting some trees (the guy sitting above the wheel which failed survived despite being out of seat showing the wheel to the conductor when the accident happened). The bridge collapsed onto the 5th car, causing the rapid deceleration of all subsequent cars. That's where all the fatalities occurred. It was just bad luck the train happened to be passing underneath a bridge just as the accident occurred.
Now, consider that with a hyperloop train, the cars will be traveling at speed a few inches from the stationary wall for the entire length of the track. It's not an air leak you need to worry about. It's an IED-type device placed on the side of the track wall, designed to blow it inwards just before the train arrives. At 700 MPH the explosive only needs enough energy to blow enough of the wall inwards to destroy the first train car causing it to block the subsequent cars. The kinetic energy of the train itself will then be more than sufficient to destroy it. When US Air 427 [wikipedia.org] hit the ground at just 300 MPH, its kinetic energy was enough to shred all the metal into pieces smaller than a sheet of paper. United 93 [wikipedia.org] hit the ground at 563 MPH, and its kinetic energy fragmented the plane into such small pieces that conspiracy theorists (who can't seem to grasp the notion that solid metal will fragment when presented with no other means of shedding kinetic energy) have gone nuts with theories that no plane actually crashed there.
A hyperloop train is going to have more than 4x the kinetic energy per unit mass of US Air 427, 1.5x that of United 93. If one strikes the wall and crashes, it kinetic energy is literally going to turn it (and its occupants) into confetti.
What makes it more dangerous than a plane is that planes fly miles away from the nearest solid object when they're at top speed (mid-air collisions excepted). Even systems designed to cause a deliberate collision (surface to air missiles) have a high failure rate. OTOH Hyperloop is going to be traveling a few inches from the nearest stationary object the entire length of its trip. So you're now faced with the prospect of protecting the entire length of track from vandalism or terrorism.
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Re:Even More Simple (Score:5, Insightful)
Assuming a hyperloop cruses at 700 mph or 25% faster, the notion of survive ability of virtually any crash, regardless of how the system is engineered, is ludicrous
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if there is probability of mass casualties and destruction to surroundings, in addition to mass deaths of passengers, hyperloop will not be built through built up urban areas. which sort of negates the its utility, better take an airplane.
(this is assuming if it is going to be built at all, i think there is way too much technical difficulties to get even to starting point, even to a real model test ) .
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"Will not be built through urban areas".
You DO realize that urban sprawl doesn't respect safety perimeters right?
Unless the land on which this is being assembled also accounts for significant safe space around the track, urban growth will eventually encroach on the track's right-of-way.
Also, bridges, and other places where public transit crosses the track right-of-way...
WHOOPS! The track was built too low in this area and a semi-trailer just hit it!
Basically, saying "will not be built through urban areas"
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Trains are a bad comparison (Score:3)
Trains are hundreds of tons and carry immense amounts of momentum and energy. A hyperloop pod would be very light, possibly weighing much less than the cargo it carries. Even airplanes are not a great comparison as they are orders of magnitude bigger and heavier than a pod. Some other fundamental differences, the pilot is not on board in a pod, a pod does not carry it's fuel. Pods will be MUCH safer for the area around the crash, and MUCH more dangerous for the passenger/s. Of course an accident could
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However the question would be, compared to other technologies, even though immediate death of a catastrophic failure, would it be over all safer than other methods.
Every day over 3,000 people a day die in an automobile accident [Source] [asirt.org]
Which is nearly the number of people who died during 9/11 [Source] [wikipedia.org]
Now if this technology can get people off the roads and onto safer transportation even if it means the probably of survival of an accident is much lower is still a much better for society.
We are fixated o
About the same thing that happens with aircraft (Score:2)
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True...
BUT, being that the whole path of the Hyperloop will be ground based, there will be MANY more points of attack along the route by those with terroristic minded activities to plan.
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Aircraft rarely hit anything in transit. They're not traveling through a confined space where a few feet of movement would mean disaster. Many mid-air accidents are survivable. There are solid statistics on it, but there are no real world stats on the hyperloop in this regard, obviously.
I think it's a very valid question, and it would be my primary concern as well. Traditional trains are very safe for their passengers, with very low occurrences of fatalities (the number of people killed by trains or in trai
Re:About the same thing that happens with aircraft (Score:5, Interesting)
Unlike a train or plane, a hyperloop is an enclosed tube where collisions *should* be non-existent unless you put multiple cars in the same tube. The most likely failure is likely stalling in which case you will need to have some way of extracting the stalled car but everyone should be uninjured. The mostly likely fatal failure would likely be a break in the tube causing a derailment and the closest we have to that would be roller coasters and large oil pipelines. Looking at the failure rate of large oil pipelines and roller coaster derailment should give a pretty good idea of the failure rate of a hyperloop.
Re:About the same thing that happens with aircraft (Score:5, Insightful)
Actually, I suspect the most likely fatal failure is going to be loss of passenger pressurization, resulting in *loss of cargo*. Cabin depressurization of an airplane is bad, but still not as bad as being exposed to total vacuum, and a plane can dive to regain air pressure. When a hyperloop pod looses pressure, there's no place to run.
Re:About the same thing that happens with aircraft (Score:5, Informative)
The whitepaper described how to handle loss of pressure in the pod. Basically it boiled down to this:
1) If the leak is small enough, compensate with onboard emergency air supply until the destination is reached
2) If the leak is big enough, initiate a system-wide emergency stop and rapidly repressurize the tube.
You could arguably repressurize the tube faster than an aircraft could descend to a safe altitude.
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Re:About the same thing that happens with aircraft (Score:5, Funny)
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But there is nothing in the tube that they can hit :D
Simple (Score:4, Insightful)
I should think a hose and shovel should do the job nicely.
Failure is not an option (Score:2)
Very bad things. (Score:2, Interesting)
https://www.youtube.com/watch?v=RNFesa01llk
Thunderfoot has done a series of videos on this topic. Even if you assume you could make a HUGE 99% perfect vaccuum with that volume of air; any failure causes its occupants to get exploded out the end somewhere. Lots and lots of energy in that system.
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I like Thunderfoot and subscribe to his channel. I'm not an advocate for hyperloop and think it is not economically feasible.
But the failure mode he demonstrates with an air hose is silly. Thunderfoot should try progressively smaller projectiles in the same-size tube to see how dramatically the velocities fall off. The hyperloop sled does not need to fill the entire cross-sectional area of the tube, and in fact that would make it very oddly-shaped for human occupation. I just don't see this as a problem tha
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Only got through about half the video, but it was pretty much entirely sensationalistic bullcrap. Take the idea that the car is going to tear through the vacuum chamber in case of failure. Why would it? The car is traveling forwards. Even if it got hit with the strongest pressure wave imaginable, it's going to be entirely from the front: none of that is going to translate into sideways motion that would result in significant stress on the tubing from the car. It's literally high school physics. Perhaps wors
Hyperloop is safer as a function of its speed (Score:2)
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Why would you think there would be cars and city buses in a sealed tube that's had most of the air pumped out of it?
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Engineers tend to think statistically -- which is a good thing. But it can produce judgments which are contrary to common intuition. That's because intuition is, from an engineering standpoint, crap.
Take automobiles. Three thousand Americans die annually in cars -- that's like a 9/11 attack every year. Plus car accidents produce a bountiful annual crop of disfigurations and crippling injuries. Yet nobody is concerned about getting in a car. Planes on the other hand are much safer. Now as an engineer trai
Re:Hyperloop is safer as a function of its speed (Score:4, Insightful)
Engineers tend to think statistically -- which is a good thing. But it can produce judgments which are contrary to common intuition. That's because intuition is, from an engineering standpoint, crap.
Take automobiles. Three thousand Americans die annually in cars -- that's like a 9/11 attack every year. Plus car accidents produce a bountiful annual crop of disfigurations and crippling injuries. Yet nobody is concerned about getting in a car. Planes on the other hand are much safer. Now as an engineer trained to use numbers as your yardstick, the natural way of thinking is this: "Since cars are acceptably safe to the public, if I can get the deaths/mile figures for airplanes down to the same level my job is done." Except that plane failures are often spectacularly horrific. People are naturally terrified of them. It's common sense to be afraid of something that moves at hundreds of mile per hour thousands of feet in the air.
So people demand very high levels of safety for aviation, which drives the cost of air travel up. OK, then; that means rationally they should also want the same deal for automobiles, which are by every measure much more dangerous. Except no, every time someone proposes making safety improvements people resist the cost, even though on a dollar per life saved basis the make much more sense than trying to make airliners even safer.
Conclusion: the natural human emotional response to risk and cost is hopelessly borked.
Now the Hyperloop is a novel form of transportation, and our bias against novelty when it comes to fear means that people will demand it be designed to be much safer than air travel even. And by design it probably is. But given the physical nature of the thing, lurking out on the tail end of the probability curve there are no doubt potential events of spectacular carnage. But they are so unlikely that given the number of people who are expected to ride the system it makes no sense.
I don't know specifically what those scenarios are; I'm not a Hyperloop engineer. But if they do exist it may be that I'm literally better off knowing.
It has nothing to do with statistics or common sense.
It has to do with control. Getting into a car meaning you or the person you trust to drive you has a great deal of control over the situation, from driving to knowing the reliability of the vehicle to avoiding external threats from other idiots on the road. Getting into the plane means you have no control and have to trust a stranger for everything.
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By that logic people would be terrified to take a taxi or an Uber. And you really don't have control if some drunk in the oncoming lane swerves into yours; your fate is up to pure luck.
The notion of "control" I think is just rationalizing familiarity bias.
Depends on sooo many things (Score:2)
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you are assuming gradual technical failure. that is too limiting and hubristic.
there can be sudden catastrophic failure, both accidental, and intentional (and even well planned) like a terrorist attack.
if hyperloop ever gets built(which i doubt for unrelated technical and commercial reasons), there will be a disaster at some point. that is a certainty.
such a disaster in itself is not(and should not be) an argument against hyperloop. but planning for that (such as not building in urban areas)would increase c
What about an earthquake? (Score:2)
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A hyperloop cab can not derail.
It uses U shaped skids that wrap around the rail, facepalm.
Trains are not strongly attached to the rail... (Score:5, Insightful)
More idiotic scare-mongering (Score:5, Informative)
IF the system started to have a slow leak the pod would have time to slow, air resistance would do it naturally if nothing else.
Also it's not like it cannot have basically "landing gear" that would be able to slow the pod from 700 MPH in the perfectly smooth sealed tube in the case that a real breach presented itself - but you do all realize that a pressure breach would not be instantaneous across the enter length of the tube, right? Then we are back to the case where pressure changes can be reacted to and the system brought to a gradual halt.
I sweat Slashdot has become a bastion of luddite nut-jobs, who seem to purposefully ignore physics. Shameful to see such a virulent example of this on the home page.
You all sound like the people who wouldn't get into the first automobiles... or modern day Amish who still will not, but at least the Amish people are generally useful.
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Please think, even if just for a moment. (Score:5, Insightful)
Air fills the vacuum at the speed of sound.
Yes, exactly. Sound is not all that fast (six seconds to travel just a mile), mostly the pod would be so remote from the source of the leak it would have plenty of time to slow down to a reasonable speed before substantial pressure reached it. Also if we are talking about small leak its not like it would INSTANTLY be a huge volume of air in front of the pod, it would be a gradual loss of vacuum and therefore simply not the "wall of air" you are scare-mongering about.
And of course, the leak would have to occur in front of a moving pod instead of behind it to even be that much of a potential danger...
A wall of air hitting you at that speed would likely kill you.
Not at 70MPH instead of 700MPH, you blithering retard.
Also I've not seen any arguments for why emergency vacuum pumps placed along the tube would help eliminate the danger from common leaks? But you didn't even think that far you were just like YABBER YABBER YABBER FLOOM DOOM!! *throws hands in air and waves frantically like muppet on acid*
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Air fills the vacuum at the speed of sound.
Where did you learn this? Air pressure travels at the speed of sound. A mass of air traveling at the speed of sound is rare. Air traveling at the speed of sound would experience a lot of friction from any static surface and slow down.
Actual discussion? (Score:2)
I know that the /. crowd has moved to twitter length replies these days, but how about a real discussion?
There are plenty of failure modes that would be completely survivable, in fact with little or no chance of injury. Tube loses vacuum? Unit slows down and stops. Loss of mains power? Same. Capsule loses pressure integrity? Masks from the ceiling time.
Yes, a catastrophic failure of the tube structure could result in deaths, but I can see the emergency shutdown being engaged system wide in such a case, resu
What kind of failure are you imagining? (Score:2)
Not sure of the mode of propulsion, if maglev, and it loses power it lowers onto wheels on the tracks and rolls to a stop. If just floating due to the vacuum pressure in the tube it will still have wheels to drop onto wh
FMEA (Score:5, Interesting)
That's ok, I'm game to start one. First we need to define the hyperloop as a system.
Next, we imagine, and list all of the possible failure modes for each one.
Rapid depressurization
Rapid depressurization
Thermal event
Explosive event
Then we discuss the effect of each failure mode, and steps that can be taken to mitigate it... Completing an FMEA usually takes hours in meetings with large numbers of engineers brainstorming all of the possibilities.
Logically.... (Score:2)
- Gradual vacuum failure: Increased drag/resistance, system sensing and ordered shutdown, survivable but recovery will require process and equipment.
- Instantaneous vacuum failure: caused by or accompanied by tube failure/deconstruction - collision and rapid dissection of the capsule, probably not survivable for all passengers.
- Instantaneous maglev failure, loss of suspension: Probable contact with tube, friction or impact force causing tube or capsule failure, probably not survivable for all passengers.
-
Hypergoop (Score:2, Funny)
It would make Hypergoop.
Security? (Score:2)
The idea of getting from one city to another at 700 MPH without having to suffer through an airport and all that jazz is revolutionary.
You'll still need to suffer through the Hyperloop terminal and security similar to airports. There's no way TSA will allow people to just walk onto a system like this without screening. Even a fairly small bomb would kill everyone onboard.
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Like commercial airliners, then. But still safer than the highway that we all take to and from work, school and the store every day.
about the same as what happens when a plane fails (Score:2)
probably about the same as what happens when a plane fails.
2cents
j
Ask a Medical Doctor in 1820... (Score:4, Insightful)
Ask a Medical Doctor in 1820 what would happen if a steam locomotive crashed... all manner of mayhem, injury and likely death - that's what the experts all said. Falling off a running horse is bad enough, but the speeds that are possible with rail transportation are far worse.
Different kinds of accidents. (Score:2)
Each individual hyperloop pod has far fewer people in it than a train, so the most important consideration is to limit damage to one pod. I guess in an emergency you can brake a pod at maybe 2g which means you'd want them at least 2500m apart. Probably round up to 2 miles. You can get braking either from ablative skids on the bottom of the pod (I saw this design in an other context) or by releasing the vacuum and air-braking.
So compared to a train crash, there may be more damage, but to fewer people.
As to w
The Cheese Slicer (Score:2)
If you wanted to cause some economic/real terror you just shoot a piece of aircraft cable diagonally through the tunnel. The car arrives in the station sliced in half. The same thing happens to your investment in hyperloop.
SD
Reddit discussion on hyperloop pop failure modes (Score:3)
Look at space stations (Score:4, Insightful)
Seriously, all of the space stations have had leaks. Most were caused by micrometeorites that hit them. How many have blown apart because of that? NONE.
For those that are claiming that hyperloop will blow up, note that the tubes will actually be STRONGER than any of the stations.
And for those claiming that physicists are saying otherwise, I would suggest that they are NOT working in the field since they are too stupid to know.
It Depends on the Failure (Score:4, Interesting)
It depends on the kind of failure. I am sure that the designers will make every effort to make the more likely failures (power loss, reasonable or minor track damage, etc.) survivable. You won't ever have many of the risks associated with conventional trains (inattentive conductors, cars or other obstructions on the track, excessive speed for the track, etc.) That said, if a terrorist blows up the track just short of the train in motion (less than stopping distance) you are very likely going to be red paste in the wreckage.
Compare the risk of death in an airplane:
loss of power - very likely everyone dies unless there is a runway nearby
any failure that causes loss of control - everyone dies
etc.
The main problem I see with the hyperloop is that in this era of terrorism, it is virtually impossible to secure hundreds of miles of tracks, whereas airports are fairly well secured, and planes are immune to terrorist attack from outside while in flight (so far terrorists haven't managed to design and build stinger missiles, fighter jets or SAM missile batteries.)
Re:Soft failure possible too (Score:5, Funny)
Similarly, what if the vacuum failed and the pod stopped in a low pressure section pipe in the middle of nowhere. The only way out if to wait for someone to figure out the exact location of the pod and cut you out. I've yet to see an estimate for how many hours (days?) you might be stuck in there in pitch blackness, likely getting cooked inside a metal tube sitting in the sun.
Its this new fangled technology they call a HATCH DOOR every XYZ meters.
Crazy tech.
Re:Soft failure possible too (Score:5, Insightful)
Hatch doors... which would be separate failure points along the way for the pressure difference to be changed.
Assume perfect seals and no malicious or accidental misuse of even a single hatch door. A tech team is sent out to to assist the passengers in getting out. You can't just open the hatch, you've 14.7 lbs of pressure per square inch trying to keep that door closed, assuming it swings out. Now you've got to pressurize either the entire system (so largely shutting it down), or the particular leg you are on. How long does this take? Now how long does it take to undo these steps?
Short of a 9/11, when there is an airplane crash, even an entire airport (or state) is shut down due to weather, the rest of the system keeps going.
This also aside from all of the issues related to thermal expansion & contraction of the materials, making the sealing even more difficult.
Hours? Days??? (Score:2)
The only way out if to wait for someone to figure out the exact location of the pod
So you don't think they will know this every second why again???
Even if they didn't have sensors lining the tube (which is obvious) they would know the departure time and velocity until system failure.
I've yet to see an estimate for how many hours (days?)
How long does it take a car to drive from one endpoint of the hyper loop to the other? Hint: in all the proposed routes I've seen that's like 4-6 hours - from the ENDPOINT
Re: (Score:2)
We now have video of crashes at 200+ MPH. Tell me those look survivable.
Re: (Score:3)
Re: (Score:2)
BUT, if it weren't for Al Gore inventing the Internet, none of these Musk creations would have come to life....
You just GOTTA go back to basics on this type thing.