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I always come to these hyperloop criticisms expecting to find some sort of fatal flaw in the physics of energy efficient supersonic travel. But to my surprise,
by Russell91 10y ago
I always come to these hyperloop criticisms expecting to find some sort of fatal flaw in the physics of energy efficient supersonic travel. But to my surprise, they instead tend to be pessimists saying things like, "You'll never get past my friends: the regulators, the government bureaucrats, and especially the lawyers!. We will drive up your costs and make you look foolish".
First, no one said that designing this thing in the USA means it has to be deployed in the USA. Countries without common law legal systems get around these unnecessary costs much easier.
Second, if these are seriously the only objections, then thank god we are actually building this thing. I could see complaints if it were some $100 billion publicly funded project, but the fact that less than $1 billion in private capital has already gone so far into demonstrating the technological feasibility of such an innovative transportation mechanism is a huge win.
- weego 10y agoI dunno... I'd feel much more comfortable if all humanities smartest technical people were trying to make the next whatsapp clone /s
- KirinDave 10y agoMaybe in elementary school people should get high marks for effort. I don't know. But in the case of a company raising funding and claiming it wants to build a ton of subsidized infrastructure to service the public, it isn't the case that we should say, "This is better than some more vacuous application of the money." Because it's not at all clear that Hyperloop is actually a good plan to reintroduce high speed rail into America when so many problems keep coming to light about it.
- xt00 10y agoHyperloop is definitely vacuous..
- na85 10y agoContrarily, I'd feel more comfortable if "idea guys" like Musk would leave the engineering to actual engineers.
- deleted 10y ago[deleted]
- wcummings 10y agoDon't challenge the Musk hero worship!
- icebraining 10y agoThen you'll be glad to know that's what he's doing with Hyperloop - he has just released the idea as a paper, but he's not directly involved in its development, which is being done by independent companies.
- ant6n 10y agoYou mean he released a paper renaming vactrains to hyperloop.
- emodendroket 10y agoElon Musk: I'll make the Wiki.
- Manabu-eo 10y agoDozens of engineers from Tesla and SpaceX contributed in the Hyperloop whitepaper. Plus Elon considers himself an engineer, even though he has a degree in physics.
- na85 10y agoI consider myself a brain surgeon.
- Xorlev 10y agoReading through the criticisms the consensus is "sure, this can work if you allocate 10-100x more money than estimated." I'm not sure if it's truly innovative if it costs more, places considerable stress (up to 0.5g!) on the rider/cargo (what the author calls a "barf ride"). The analysis picks apart the touted benefits of additional speed when ultimately the capacity is lower and it takes longer to depart. In the case of cargo, the author argues that the "last mile" of cargo takes the longest, and as such there's little benefit to sending it at 1200kph if it then needs to be offloaded and trucked around anyways. To summarize: - construction costs are underestimated or completely wrong - capacity is lower than standard HSR - Hyperloop claims power usage is higher for HSR than it actually is - forces aren't adequately accounted for even with canting - assuming perfect canting the pylons must take the additional force - the majority of travel time is to/from the station + security screening. To me, it seems like it's optimizing for the wrong section of the trip.
- notahacker 10y agoI think the biggest point the article makes is the great deal of care that needs to be taken in packing loads to meet weight requirements and avoid movement of goods in transit. What makes sense for international air mail doesn't make sense for a four hour journey by truck, especially if that truck can take a container straight from the ship to the city depot without carefully repacking everything, or go door to door with smaller loads.
- woodpanel 10y agoYes. With what exactly does freight-hyperloop try to compete? Trucks are more flexible while freight rail is struggling on most routes and speed seems of least concern there.
- bwilliams18 10y agoMaybe I'm totally unaware, but don't trucking, air freight and sea freight have the same problems w/ regards to weight requirements and movement of goods in transit? Is this not a solved problem? Build Hyperloop Freight to fit a ULD and we're all set no?
- treelovinhippie 10y agoPessimism seems to be the default for the HN hivemind. Would be cool if we all just encouraged everyone working on moonshots.
- icanhackit 10y ago> Pessimism seems to be the default for the HN hivemind. At the time of typing this the pessimism has been entirely reasonable and I'd say in the minority, with Xorlev outlining the fundamental issues with Hyperloop (capacity, costs, solving the wrong end of the problem) and KirinDave pointing out how while yes, there are more vacuous ways of spending money, when you're mucking around with other people's dough there's an expectation on return on investment, otherwise it's a charity. I'd like to see the Hyperloop built just as I'd like all kinds of cool, complex and not necessarily practical technologies develop. But it's not unfair to point out the economic and physical realities that will get in the way of those things.
- mojomark 10y agoNobody here is trying to crush dreams. The author, and many others, are simply trying to point out that there are much better uses of time and money. The factors (i.e. physics) underpinning the economics of freight shipping in all forms are well understood. Can a hyperloop be built? Sure. Is it better than existing intermodal cargo shipment infrastructure? Yes and no. It certainly offers speed, but doomedly at the expense of economies of scale: https://www.usmma.edu/sites/usmma.edu/files/docs/CMA%20Paper%20Murray%201%20%282%29.pdf https://www.usmma.edu/sites/usmma.edu/files/docs/CMA%20Paper... Here's a thoughtful assessment by Olaf Merk posted last month that draws the same conclusion as the author: http://shippingtoday.eu/musk_maritime/ http://shippingtoday.eu/musk_maritime/ Bottom line, if you can find enough high value bulk cargo that benefits significantly from high speed transit to only two or three "ports", then hyperloop is your answer. However, that's a very (perhaps nonexistent) niche in the industry. What we (transport engineering community) need to be expending resources on is: a.) eliminating greenhouse gas emissions, b.) designing a system of transport that scales with global trade demand (vice building 20K+ TEU megaships that can only be served by a few ports and promote trucking congestion in ports). Autonomous shipping, AI implementations in both freight forwarding (the logistics side) and transport control systems themselves, and applications of H2 fuel cells are technologies with great promise.
- maxerickson 10y agoAren't the acceleration figures a criticism of the physics? Same with the argument about centralization. It's a practical non starter if sticking the load on a truck that just goes to the destination is faster than shifting the load off the truck onto the hyperloop and then back onto a truck.
- konschubert 10y agoMaybe there is no single fatal flaw. The point is, though, that there are many, many issues that need to be addressed and it is very clear already now that the hyperloop will be uneconomical. In other words: It might be possible to force it into existence, but it won't be worth it.
- deleted 10y ago[deleted]
- problems 10y agoThe best legitimate criticisms I've seen are here: https://m.youtube.com/watch?v=RNFesa01llk https://m.youtube.com/watch?v=RNFesa01llk Basically expansion and contraction as well as just plain vulnerability of running a vacuum make it extremely difficult to do practically. The phrase he uses, "all the problems of space travel except in a gun barrel" is a pretty accurate description of the issue. Any loss of vacuum will almost guarantee loss of life. No realistic demo has been done even on a small scale as of yet.
- dpark 10y agoWhy would loss of vacuum necessarily result in loss of life? I would expect loss of vacuum to result in sudden deceleration, but not with a deadly level of force.
- problems 10y agoAir being drawn in results in pressure on the capsule, propelling it. Check the video out for a demo.
- deelowe 10y agoThat demo is unrealistic. The entire end of the tube isn't going to open all at once. Instead, any realistic leak would be pretty small in comparison.
- UnoriginalGuy 10y agoI don't understand why a tube section couldn't come away? What if a bomb went off, a truck hit a support beam, or an earthquake caused a section to topple over... I don't think it is unrealistic at all.
- deleted 10y ago[deleted]
- Spooky23 10y ago
- imaginenore 10y agoThat's a strawman. Most of the criticisms are technological and security related. How do you keep an enormous vacuum tube with fast-moving pods inside secure against even simple attacks?
- aaron695 10y ago? Derail a train = put a rock on the tracks.
- imaginenore 10y agoThat will maybe derail one train. Versus the whole tube exploding at the speed of sound and/or the shockwave hitting every pod traveling at speeds designed for near vacuum.
- Manabu-eo 10y agoPhysics 303: "pipes are not lossless! Friction and viscous interactions between the entering air and the tube wall will slow down that "shock front" to a highway speed wind in only a couple km." (quote from schiffern post). You may want to look at derivatives of Bernoulli's equation, like Darcy–Weisbach equation. Plus there is a planned emergency repressurization of the whole tube that would eliminate even that medium speed shock front. Plus a small 10cm diameter bullet hole would imply in less than 1% of the flow of a completely broken tube (a much harder feat to do), per laws of conservation of energy and matter. As pods travel with 4km or so of separation, at most one pod will be affected. That is much less people than a derailed train.
- bduerst 10y agoIt's a criticism common to most future tech, not just the hyperloop. For example, there was lots of hang-wringing over Fusion power back in the 1970's, about how if the bureaucrats would just give it more funding then it would happen: https://upload.wikimedia.org/wikipedia/commons/a/ab/U.S._historical_fusion_budget_vs._1976_ERDA_plan.png https://upload.wikimedia.org/wikipedia/commons/a/ab/U.S._his... I'm not saying any of this tech is without merit, just that it's common to need buy-in from many organizations to make it happen.
- Spooky23 10y agoWhat part of "acceleration will lead passengers to vomit all over themselves" is a bureaucratic issue?
- notahacker 10y agoTo be fair, Musk's original paper advocating the concept was structured as a criticism of the supposed inefficiency of rail alternatives, and was heavy on deliberate cost underestimates and light on physics. So it's not exactly unreasonable that most critiques start off with the economics. This critique, however, raises quite specific physics-related logistical reasons why Hyperloop is a ludicrously impractical solution for most forms of freight and uneconomical for the rest. Things it doesn't mention, even implicitly, include regulation, government and lawyers. Perhaps you'd get more out of these hyperloop criticisms if you read them?
- the_duke 10y agoso many are using the 'playing at moonshots with other peoples money' criticism. It's not like investors are blind or dumbstruck just because it's an idea from Musk. They do their due diligence and if they think the plan has potential, they invest. I'm sure there were countless technical issues and big challenges around airplanes in the initial stages. And cars. And trains. And, you know, every new technology. Could Hyperloop (One) fail miserably? Sure. Could it succeed? Also. Let's just wait and see. Also, whenever there are invested interests of established competition, they usually drum up the PR machine against new ideas, just as a precaution. Just look at the fascinating history of fridges vs ice box companies for one of countless examples.
- rootusrootus 10y agoOne need look no farther than Silicon Valley to see a plethora of starry eyed investors who are either blind, dumbstruck, or simply haven't done due diligence. Isn't the bubble about to pop... again?
- the_duke 10y agoI don't think we are in a bubble anything like the dot com debacle. The industry as a whole is far more mature now, and paths to monetization are clearer. Competition is high, so is the competence of most VCs and investors. I'd also place an engineering project like Hyperloop in a whole different space than the typical SV stuff.
- knieveltech 10y ago"paths to monetization are clearer." Indeed. Try to generate enough hype to bilk IPO investors or failing that get bought out by a firm that actually makes money.
- tptacek 10y agoJust now, I read this piece and the linked New York Magazine piece (which, without mentioning regulators, managed to make the whole outfit sound like the kind of scam Hacker News usually delights in outing). I do not see any arguments of the form you're suggesting. It's not the author's friend "the regulators" that are going to make the Hyperloop fail; it's his friends "physics" and "economics".
- eruditely 10y agoStatute law systems are the socialism of law, Common-law, this collaborative law making is the 'free market' problem, and it does not have a calculation problem via the legislator/statute marker.
- Lazare 10y ago> I always come to these hyperloop criticisms expecting to find some sort of fatal flaw in the physics of energy efficient supersonic travel. But to my surprise, they instead Except, as the article points out, it's not actually faster, cheaper, or efficient than competing technologies. Those seem like really fatal flaws. > Countries without common law legal systems get around these unnecessary costs much easier. That same logic also applies to the competing technologies. The same magic wand that lets you build a hyperloop for 1/10th what it would cost in the US also lets you build the tracks for HSR for 1/10th what it would cost in the US. You can't compare the cost of building a hyperloop in China to the cost of building HSR in California and get a meaningful answer. Nobody is saying that the hyperloop is impossible; they're saying that it's a plan to build something objectively worse than high speed rail at prices that seem broadly comparable.
- cbsmith 10y agoI think you are misinterpreting the criticism. There's a difference between "regulator, bureaucrats & lawyers will stop you" with "there is no compelling advantage with this approach. It's flashy and all to say you're going to break all the rules, but you could just as easily do that with conventional means of transportation.