Reality Overtakes Hyperloop – Streetsblog California
Doesn't look too good for the Hyperloop concept.
Doesn't look too good for the Hyperloop concept.
RIP Hyperloop?
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jis
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Don't worry. There will be someone in Florida who will still think it is a great idea and sink a lot of money in it. Afterall this is where land is sold by the Gallon.
And before anyone complains ... I live here. What does that say about me? 
George Harris
Engineer
And how many gallons of land is it that you say you own?Don't worry. There will be someone in Florida who will still think it is a great idea and sink a lot of money in it. Afterall this is where land is sold by the Gallon.
(l have two children that are living in Florida. One near Miami, the other in Pensacola.) Then there is the joke about hurricanes: If you live in a low lying area and hear that a hurricane is coming, you should leave for higher ground. Look at your driver's license: If it says Florida, you live in a low lying area.Now back to our regular programing: This whole Hyperloop concept made me wonder about Musk's rationality. To me it looked insane on its face. No matter how fast, it is not the horizontal equivalent of an elevator. Do you really want to be put in a capsule with several strangers and thrown through a vacuum tube? I think for 99%+ of the population, the answer is no. Remember, what Musk has done to date, the electric car and space travel, do not require development and construction of a right of way, and are really in many ways baby steps beyond existing technology in these vehicles. What he did was as much put together known technologies in new and different ways for his automobiles and rockets instead of developing truly new technologies. The Hyperloop cannot be a scaled up equivalent of a bank's vacuum tube at the drive-through. Paper does not care about G forces. People do. Unless you plan to remove your passengers with a large spatula, and don't worry about ever having repeat customers, you acceleration, deceleration, and curving forces will need to be limited by comfort and safety of acceleration, generally in the range of no more than about 0.1G. What this means is that changes in direction will require very large radius curves, and I mean radii in the multiple thousands of feet range. Generally, for comfort you want a 100 mph railroad to have curves of one degree or smaller (5,729.65 feet radius or larger). Since acceleration is a function of V^2, to double the speed you would need four times the radius. If you are talking say 400 mph, you would need a minimum curve radius of 16 times that for 100 mph, so say 92,000 feet or larger radius. For short distances, the lengths consumed in acceleration and deceleration render high maximum speeds pointless. I have ridden the Shanghai Airport maglev, and that is exactly what happens there. You spend roughly half the trip accelerating from start and the other half decelerating to the stop. This leads into discussion about safety and evacuation. How do you deal with that in a vacuum tube? When they had the fire on the Shanghai Maglev, the thing that saved them from multiple fatalities was access to the line by fire trucks with their ladders. The German system Maglev vehicle wraps around the guide way. Thus there is no parallel safety walk, nor can there be. In the Japanese system Maglev, the train sits within a more or less U shaped guideway. Thus, there is a walkable path on both sides of the train. But with the Hyperloop, how do you evacuate the capsule? You can't walk out into a vacuum. With this there is also the need for emergency access points, How do you manage that? I think one of the major things that led Musk to claim extremely low cost in tunneling was ignoring, or likely even ignorance of these realities in tunnel construction and operation. Then you get to the issue of connections between tunnels. The complexity of the equivalent of a railroad turnout for a Monorail or Maglev is a major cost issue in both construction and operation these type systems. Think about how you would manage this in a tube type operation. I haven't tried to figure that one out and have no plans of doing so.
And one more thing: Without the vacuum or near vacuum in the tunnel, the high speed becomes quite impractical, as the capsule is effectively a piston pushing a large plug of air. So move the car by the air you say? Then you have to be pumping massive volumes of air. Economically and for energy savings, you have lost. This gets around to another point with maglev: Yes, with maglev you eliminate the rolling resistance between wheel and track. However, as speed increases this becomes an ever smaller factor in total resistance. Again you get to multiplication factors. Resistance is effectively a quadratic equation, R = C + W*v + A*v^2. That is, there is a constant resistance to movement that is not speed related. Then there is the rolling resistance which is essentially directly proportional to speed, and finally the aerodynamic resistance which is proportional to the square of speed. I have heard that as you get to a significant fraction of the speed of sound or is it just if at the speed of higer there is a v^3 factor that comes into play, but I know nothing about that one. Aerodynamic resistance is significantly higher in tunnels than in open air, so without the vacuum if in a continuous tube you are worse instead of better so far as energy requirements are concerned. A lengthy technical paper or even a book could be written about aerodynamic factors in resistance to movement under varying conditions, so I intend to say no more here.
A further short thought on rolling resistance - that is the wheel-rail-internal mechanisms that are directly proportional to speed: For equipment designed for high speed operation this factor is quite small, as the need for high speed operation requires a very smooth track and very low internal friction is the machinery.
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Missouri too Missouri Hyperloop My state can't figure out how to rebuild I-70, fund a second St. Louis - Kansas City Amtrak trip, and adequately fund Medicaid, but they are all-in on the hyperloop.Don't worry. There will be someone in Florida who will still think it is a great idea and sink a lot of money in it. Afterall this is where land is sold by the Gallon.
Funny how outlandish projects like this "create jobs" and have all these other benefits but conventional rail projects are never credited with any of this. Have any actual hyperloop prototype been built and operated yet?
Wikipedia is your friend:
Hyperloop - Wikipedia
The TUM record was broken in a one-mile long tube. And I think it was a scale model tube, too.
Elon Musk promises new Hyperloop tunnel after speed record broken - The Verge
Frankly, I don't know how one can accelerate anything to 288 mph and then decelerate it in a tube only a mile long.
Eurotube is also only a scale model and only 2 miles long. I suspect neither of them has curves, so even if they do operate successfully, they really aren't any sort of "proof of concept."
I read in the newspaper sometime in the past several months that Hyperloop is dead now, even as a concept. BTW, after I contacted a space exploration expert who was on NPR, he agreed that settling people on Mars (as I think Musk advocates) is ridiculous with everything from temperature to natural breathing impossible. It takes only hours rather than months to go back and forth to Antarctica, we can breath there, water is not a problem, etc. but nobody has settled the place or plans to. Oh that the billions were spent on rail.
wildchicken13
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A few test tracks have been built at various research centers, but as far as I am aware there is no operational hyperloop anywhere.
George Harris
Engineer
Yes. Most of the "oh wow, how wonderful" about it are such things as ignoring the laws of physics, reality of cubic feet per person for a transportation vehicle, effects of acceleration / braking on the human body and psychology of being stuffed in an enclosed tube. Oh yeah, let's not forget basic safety issues for evacuation, etc. I have in the past put some numbers on several of these things, but I will not here and now. If you try to make this stuff "rocket science" you will in a hurry find out that public transport is not the place to use it. The energy consumption for high rates of acceleration all the way to high speed is simply huge. Passengers would have to be strapped in as well.
I hadn't considered that it could be used for trash disposal.
Metra Electric Rider
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Well.... Those oh so serious Swedes are way ahead of ya with that!
May I present for you, the Scrap Canon (I think it's pretty self-explanatory even if you don't speak Swedish):
Devil's Advocate
⠀⠀⠀
The more you learn about Elon Musk the less relevant he seems. Many of his proposals start to resemble expensive half-measures and magical thinking when viewed with a critical eye. Projects that are likely to come with an enormous opportunity cost that has little chance of paying off over the long term. I've personally lost interest in most of what he says and cannot figure out how he intends to fit so many competing views into a single coherent future.
George Harris
Engineer
Agreed. The Tesla sells as an "oh wow, how wonderful, what we are doing for the environment feels good" vehicle primarily to the upper income component of society and is marketable only because of huge subsidies in the form of tax breaks and again a subsidy in the non-payment of road use fees that are paid through the per gallon taxes on gasoline and diesel fuel. My first though on these things is that in automobiles we are into a recycle of the 19 teens and 20's where the everyman's car was a 4 banger, primarily the Model T Ford and knockoffs with cars having more cylinders and lower gas milage for the wealthy and those that wanted to make a "statement" and the electric cars were rich old ladies' vehicles for short range trips. I recently saw that over the life of a vehicle you saved about $4,000 in operating costs with an electric vehicle opposed to a gasoline powered vehicle, but whoopie ding, the difference in cost of the vehicle is far over $4,000, so, economically owning an electric vehicle is still a net loss even with the subsidies from the rest of the taxpaying public.
The Hyperloop? As I have said quite a few times with reasons given, is a science fiction solution looking for a problem to solve. One classic example of not understanding reality was an artist's rendering of a hyperloop tube going across the mouth of San Francisco Bay parallel to the Golden Gate Bridge at a low elevation on multiple spans. Why? I don't know. Maybe to illustrate simple and cheap, but it is unacquainted with reality. Why is the Golden Gate Bridge high and on one single long span? It is not just look pretty, which it certainly does, but it is high because it is over a major shipping channel which requires the high clearance, and it is long span well beyond the width needed for shipping because of the depth of the strait.
His space ship? Not sure about that one. There are a few things I have read that suggest that there may be a potential problem but I don't know enough to really say, but I will say, I am not taking a trip on one even if offered a free ride.
Traveling 700mph in a windowless, vacuum tube for an extended period of time? how could this go wrong...
jis
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MODERATOR'S NOTES: A number of posts on Electric Vehicles have been moved from this thread, which is a thread about Hyperloops, to a new thread:
https://www.amtraktrains.com/threads/electric-and-hybrid-road-vehicles.81558/
Please direct the EV posts to this new thread and post only Hyperloop related material on this thread. further EV posts on this thread will be removed.
https://www.amtraktrains.com/threads/electric-and-hybrid-road-vehicles.81558/
Please direct the EV posts to this new thread and post only Hyperloop related material on this thread. further EV posts on this thread will be removed.
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AKA fools and their money...
Possibly convert these sections into homeless housing
The movie "Don't Look Up" was barely worth viewing, but it had a great Musk imitation and a very appropriate ending...
https://www.netflix.com/title/81252357
https://www.netflix.com/title/81252357
RIP, but the real goal was to kill or at least delay public transit progress. And that has happened.
Can elected officials get back to planning and financing transportation projects that will actually work and serve the people?
Can elected officials get back to planning and financing transportation projects that will actually work and serve the people?
Hopefully this isn’t too dangerous off-topic, but that movie had the most realistic depiction of an ELE comet strike.
Back to the topic at hand, I’m very curious what the next gadgetbahn sensation will be.
Didn’t some info leak that musk basically pushed this idea to foil CAHSR or am I misremembering
JamesWhitcombRiley
Lead Service Attendant
They look remarkably similar to the offshore windmill mast sections staged at a former container port in Portsmouth VA. (That part of the port moved to a new, more automated facility upriver.) They're just north of the entrance to the Midtown Tunnel. Yes, South Florida has a Northeast Corridor, and Hampton Roads has a Midtown Tunnel.
