A skeptical response to Musk's hyperloop
pedestrianobservations.wordpress.com
pedestrianobservations.wordpress.com
In all fairness, I would give much more slack to an engineer talking about his field. But, as the author himself points out, almost all civil engineering technology is from the 19th and early 20th century. He seems to think that, in between, his colleagues have been perfecting the fine forms of the art and polishing its many facets. Except feats that were once fairly common, such as building the Hoover Dam under budget and two years ahead of schedule [1], are in the realm of the mythical these days.
An analog here would be if Musk had a proposal to take an existing, working mode of transit (at least working in prototype) and build it for less. But the current proposal is more like hard sci-fi: goes into enough depth to be back-of-the-envelope plausible, but no detailed engineering or working demonstration, and very hand-wavy cost estimates.
[1] http://en.wikipedia.org/wiki/Comparison_of_orbital_launch_sy...
This isn't nitpicking. Dealing with the acceleration around curves is going to be a problem for any transit system and at higher speeds it becomes a bigger problem. Unlike bathrooms, this is going to be intrinsic to any system that carries human beings. As the author points out that the hyperloop proposal has significantly higher acceleration than any other high-speed system that he knows about.
So, how did the hyperloop designers decide that 4.9 m/s^2 would be safe? Did they find some study which tested this level of acceleration on average people? Did they conduct their own study which overturned conventional wisdom? Did they look at the research which led to the 4.37 m/s^2 figure and determine that it was fatally flawed? This is a critical issue and if the designers don't explain themselves, then it's fair to assume they made it up.
The hyperloop proposal contains innovative elements (air suspension in evacuated tubes) and elements which are essentially common with many other transit systems (viaducts, human passengers). The designers deserve credit for the former, but they can't sweep the details of the latter under the rug. The point of references is not stylistic and not to name-check previous work. The point is that when you're doing something, which has had lots of previous research, you either use that research to justify your claims or you explain why yours will be different.
> The really interesting, constructive questions: does this low-pressure air cushion thing really work? what are some factors that we need to explore to determine its true efficiency?
Those are interesting questions and if Musk had proposed just the air cushion technology, then that's all we would be talking about. People would build test pieces to validate the technology and then go looking for applications. Instead, Musk choose to also include a specific proposal for a replacement for the LA-SF high-speed rail line and to estimate the costs at a tenth as much. That's what got the most media attention and so that's the aspect the OP chose to criticize.
BTW, you seem to be implying that the OP is a civil engineer or a transportation engineer with an axe to grind, but he's just an amateur and if you look at his other posts you'll see that he has a lot of concerns for reducing the costs of infrastructure projects.
- Do we have studies that estimate the effect of lateral acceleration on motion sickness? What do they indicate (e.g. 0.1% of passengers get it at 4 m/s^2, 2% at 5 m/s^2 etc.)?
- To what extent is motion sickness in HSR comparable to the proposed system? Are the differences (no outside visibility, different vibrations model, possibly different seating) significant and if so how?
- To what extent do potential passengers care about motion sickness? Has anyone compared cost and convenience trade-offs for systems with different expectations of motion sickness e.g. ferry vs. train? How comfortable are passengers with self-medication in such contingencies?
Etc. And motion sickness is only one of hundreds of possible serious weaknesses in this project. But this is inherent in anything that hasn't been tried before; anyone can think of hundreds of ways in which it can go wrong. Does this mean we should never work on anything that isn't fully proven?
You're comparing apples to oranges here. If I understand the OP correctly, the 4.37 m/s^2 (which is a claimed maximum, not actually in practice, but let's ignore that) is in the plane of the ground. Canting will convert that acceleration into a mixture of horizontal and vertical acceleration, as experienced by the passenger. The hyperloop track has 11.1 m/s^2 of acceleration in the plane of the ground based on their path assumptions (= (480km/h = 133 m/s)^2 / 1600 m), which the OP claims can get converted to 5 m/s^2 of vertical acceleration. This 7 times greater than "track specifications" of 0.5-0.67 m/s^2 and 5 times greater than the 0.93 m/s^2 of vertical acceleration coming from the Transrapid's 4.37 m/s^2 in the plane of the ground.
To step back for a minute, the issues with curve radius for high-speed transit have existed since the beginnings of high-speed rail 50 years ago and maybe longer. It's one of the major issues preventing Amtrak from going faster in the Northeast corridor, for example. If there was some easy way (blocking windows, lowering vibrations, changing expectations, self-medication) to deal with it, our first assumption should be that someone's already tried it. If Elon Musk had some new, breakthrough ideas in this regard, then our assumption should be that he would somehow mention it, rather than expecting the Internet to figure it out from the numbers he uses.
In the absence of evidence that any of the thousands of people who have designed high-speed transit allow for such sharp turns, or that the hyperloop designers have any way to mitigate the effects of high acceleration, I think the most likely possibility is that they (some of whom work for SpaceX, remember) used acceleration limits coming from the space program. Since they seem never bothered to compare to look at actual high-speed rail systems, they never noticed how different their assumptions where.
The Hyperloop document was obviously putting a flag up a flagpole to see who salutes. It had a few man-hours of estimations put into it. It looks like that, obviously.
So the numbers need improvement, sure. Its nit-picking when you get all emotional about it and trash the author.
But many of most important (and show-stopping) principles involved are the same, and those are what tend to cause delays and increase costs - things like running into unexpected geology, dealing with NIMBY's, the eminent domain process and so on.
He seems to think that, in between, his colleagues have been perfecting the fine forms of the art and polishing its many facets.
They (we) are. Want to see for yourself? Go to the Transportation Research Board annual meeting in Washington D.C.: http://www.trb.org/AnnualMeeting2014/AnnualMeeting2014.aspx
Except feats that were once fairly common, such as building the Hoover Dam under budget and two years ahead of schedule [1], are in the realm of the mythical these days.
You can say the same about the original elevated Boston Artery, the 19th century railroads, etc. The biggest difference between the mega-projects of old and today involve 1) the environmental process and 2) commitments to worker safety. It's fairly easy to build a project quickly when you don't care about splitting neighborhoods, killing/maiming workers and contaminating soil. The environmental process in particular has been a double-edged sword - it's done well in protecting the environment and communities, but it also provides means for anyone who doesn't like any facet of a project to significanty delay (or kill) it.
I don't see why environmental and safety considerations are such big unknowns, I think we have a pretty good handle on both by now. Are they factoring to build it with pollution and no safety when they estimate the cost and schedule these days?
In fact, if you read about the history of Hoover Dam there were a number of these things that they weren't legally mandated to do back then, but did them anyway. For instance, workers were offered employer-based health insurance (an arrangement that later evolved into what we know today as Kaiser Permanente).
In terms of a specific project, not really. Look at everything that goes into an environmental study: watershed/water quality, affected wildlife/endangered species, noise & vibration, soil contamination, archaeological issues, visual impacts, rodent/pests, etc, etc. On top of that, you have to consider the effects of all of those areas during construction and ongoing operations for 20+ years. And that doesn't even account for NIMBY issues.
When you're getting into the details of a specific project, it can quickly become overwhelming, especially if you have people who may be philosophically opposed to the project hammering you with those issues time and time again.
Are they factoring to build it with pollution and no safety when they estimate the cost and schedule these days?
When you look at a project at a high level, you make general assumptions, but as you get more detailed and you know specifically what kind of equipment
Take for example, tunneling: At the start of a project, your best information tells you that the sand down to 70ft below grade is clay, so you make your cost and construction estimates using this assumption. You get into detailed design and send drill crews out to collect sample borings and you find out that in much of the area where you assumed sand, you actually have bedrock coming up to 10ft below grade. Now you're plans have to change - instead of doing cut-and-cover tunneling everywhere, you have to blast in some sections, which means having to get a blasting contractor, deal with protecting nearby structures, changing traffic patterns to allow for the blasting etc. In the old days, the project would have just blasted, and if someone's foundation got cracked in the process, too bad. Today that won't fly.
edit: just saw your edit
In fact, if you read about the history of Hoover Dam there were a number of these things that they weren't legally mandated to do back then, but did them anyway.
Compare the number of people killed at the Hoover Dam project compared with the number killed during the Big Dig.
That being said, I'm by no means persuaded. If the original technical estimates can't be completely precise, why do they always happen to always be inaccurate on the bad side these days? How come they rarely plan for bedrock and get a lot more clay instead?
Overall, I understand there are new challenges today that older projects didn't encounter. On the other hand, they also had serious challenges that we don't meet (very bad transportation network, frequent strikes, including the wildcat variety, a much less educated workforce etc.) Maybe it's even true that, despite all the new technologies and infrastructure to help us, the cost per unit needs to be higher these days and work needs to proceed more slowly. But that still doesn't explain why projects almost always still run over that higher cost and longer schedule.
I don't have time to find it right now, but I remember reading a study a few years ago that showed most projects to in fact come in on time and on budget. It's the few major projects that make the headlines that have schedule & budget problems, and (to no surprise) those tend to be the projects that have to deal with the most complexities. It's not different than large software projects.
On the other hand, they also had serious challenges that we don't meet
Sure, but they could work around those problems by (literally) throwing bodies at that project and dumping crap into rivers. And some of those things you indentifiy as problems ("very bad transportation network," "less educated workforce") aren't really problems - "less educated" means "cheap": the project just needed to train you to hold a rivet in place or swing a hammer, today's workforce needs to know how to manage complex diesel equipment. "very bad transportation network" means "more room to work": building the Hoover Dam in the boonies is in many respects much less difficult than building the 2nd Avenue subway under a crowded Manhattan or building the Big Dig under a busy Boston. In fact most of the high cost of CA HSR isn't from building the sections in the boonies (which is why they're starting construction there first), it's building the connections into the heavily populated metro areas like San Francisco and LA.
If you ever have the chance (and you're an American), go to a public meeting organized by a huge capital project. Listen to all of the comments (ranging from measured to angry, reasonable to crazy) and keep in mind that the project has to address all of those concerns. That will give you a sense of scale of the problem. In fact I spend this past weekend dealing with concerns that frankly defy the laws of thermodynamics, but the project has to address, which means I spend billing hours debunking it.
edit: enko makes a good point, you could go ulta-conservative with cost estimation, but then every highway widening project becomes a $100 billion undertaking and nothing would ever get done. Projects to set aside 5-15% for continengy and most of the time that's enough. Of course there are outliers, and those are what tend to get attention. You also have times were a project may also set a relatively low budget, but they get back bids from contractors and/or engineering firms that way exceed the budget, so the budget gets increased.
I don’t think we should do the high-speed
rail thing because it’s currently slated
to be roughly $70 billion but if one ratio
is the cost at approval time versus the
cost at completion time of most large
projects I think it’s probably going to be
close to $100 billion.
And, according to this:
http://californiawatch.org/dailyreport/bullet-train-bidder-h...
...the lowest (and winning) bidder for early work on the California HSR has a history of cost overruns, so things aren't starting out so hot.
Your last paragraph seems to say that we don't want accurate estimates because then we might not do the projects. That's the point of knowing the costs. We don't want to do projects that are too expensive.
Large projects, like Hyperloop or HSR, are probably the ones particularly likely to be "outliers" (if indeed projects with overruns are outliers) and big projects are the ones where that damage costs the most, so it's a double whammy.
Meanwhile, if we're now accepting that lowballing is a good idea, as your last paragraph says, then I don't understand why you seem to be defending the original article as Musk must just be lowballing and he expects overruns. It will take a lot of overruns to catch up with the ostensible California HSR budget.
I will say that, with SpaceX, Musk and the government have fixed-price contracts, so SpaceX eats cost overruns. They also have the lowest space cargo delivery cost for their class. This gives me some evidence that Musk could deliver more cheaply and on budget than the linked industry observer expects.
No, my last paragraph says we don't want ultra-conservative estimates because we would definitely not do the projects.
Meanwhile, if we're now accepting that lowballing is a good idea, as your last paragraph says
My last paragraph doesn't say that.
This gives me some evidence that Musk could deliver more cheaply and on budget than the linked industry observer expects.
Perhaps. But if I were a betting man, I think Must will be in for a rude awakening upon discovering the mess that is the public environmental process, as have many other entrepreneurs before him.
Well, an obvious factor is that there is a huge incentive to under-estimate for anyone with an interest in the project's green light. The cheaper a project looks on that initial paper, the more likely it will be approved, and if/when it goes over budget, what are they going to do? Cancel it with the tunnel half dug?
It's a political/societal problem of poor economic ideologies, lowest-bidder pricing and misaligned incentives, coupled with a low aversion to - or even understanding of - economic crime.
And it's by no means limited to these mega-projects. I know a certain software company who specialises in winning contracts by low-balling the price, expecting to argue it up later when all sorts of "unexpected" issues arise - those same issues the losing bids allowed for. Pretty much the same game.
https://twitter.com/TalulahRiley/status/320421724644573184 https://twitter.com/TalulahRiley/status/320422298618302464
Just to toss in an entertaining data point.
And I did not know the Hyperloop would not actually go into LA proper. That's a significant difference to me. That last leg into LA is where a lot of the traffic trauma happens, the part I would most want to avoid.
Ultimately both "sides" need to work with each other. The entrepreneur pushing the envelope, and the engineer making sure things are feasible.
Buildng projects on the scale of the Hoover Dam (whether under budget and ahead of schedule or not) were never "fairly common".
It's quite possible that there are valid criticisms embedded in between the vitriol but I wished he'd stick to the factual stuff and leave his bias out of it. Calling Elon Musk a crank is an insult given what the man has already achieved and reflects poorly on the writer.
I personally think that the best way forward with the hyperloop is to create a scale model, the tube and carriage could be (virtually?) wind tunnel tested and valuable information would be gathered that way offering a path to verify the design one step at the time starting with the hardest part, the aerodynamics.
Thus we get Hyperloop, a loopy intercity rail transit idea proposed by Tesla Motors’ Elon Musk, an entrepreneur who hopes to make a living some day building cars.
... was just an immature and catty way to begin a (what he hoped would be) substantive attack on the Hyperloop.
The article finds some questionable issues in the initial proposal, but its unfortunate that Levy writes as though Musk is a jackass for even putting the idea out there.
not sure what that has to do with elon musk, other than to try and put together a "nuclear" attack on his character, going after the moral foundation of his wealth in addition to the hyperloop idea. it's like the article is a communist critique wrapped in a technical evaluation.
away from the radical and bitter aspects of this critique, i appreciate the technical comments in here. i think it is vital to have a proper, public technical evaluation of the hyperloop, and he undermines his argument with the personal and philosophical. i would love to see a response to this critique from the hyperloop side.
i would agree that musk, having lobbed this hand grenade into public discourse, should follow-through on his idea to some extent - build a test bed and prove it can be done on a small scale. in my limited experience, if something is a really good idea, you try and pursue it for yourself, rather than hoping someone else will steal it from you.
Alternately, the proposal could have avoided making detailed claims on cost and routing, and instead focused on the high-level technology, more in the direction of validating the basic idea, and leading up to a test track. There's nothing wrong with that. But if you're going to claim you can build a line on a specific route for a specific cost, you need to do the work to justify those numbers credibly. Musk's existing document, at least, comes off as very hand-wavy and lacking in empirical grounding for any of its detailed engineering and cost estimates (that grounding could be rooted in his own data, or in existing data, but there has to be data somewhere).
2) I did not claim Levy is a transportation engineer
3) Musk did this quite handy, he did not propose the hyperloop in a vacuum (pun intended) but for a specific application, this increases the chances of something being done with it
You have to start somewhere, think of this as a first proposal that can be suitably amended or scrapped in its entirety as more insight is gained.
I'm pretty skeptical about the whole thing but Musk has a history of pulling off impressive feats and I would not put it past him to come up with something that might work when tweaked. So let's hear it for constructive criticism (fix what is broken or provide actual proof why it can not work) rather than outright dismissal.
But from that perspective conventional HSR is easy and cheap, too. You could sketch out a reasonable LA-SF HSR system with optimistic assumptions and put a $15 billion pricetag on it. It also has the benefit of being technically validated, and implemented in practice: Japan, France, and China have all built working systems for per-mile costs in that range or less. The California HSR issues have more to do with a mixture of politics and the U.S.'s "unique" regulatory setup, and it's not clear how hyperloop plans to sidestep those, even assuming the technology works exactly as envisioned. If Musk has some secret on how that's going to happen, I'd like to use it to just build conventional HSR!
Put differently he seems to be offering a technical solution to a problem that didn't have a technical bottleneck, and it's not even clear the technical solution works.
I did not claim Levy is a transportation engineer
You at least very strongly implied it. What did you mean his agenda was then, if he isn't a transportation engineer? If his agenda was that non transportation engineers should mind their own business, why would he be commenting on the math and engineering of it? That's not a coherent reading of what he said.
However, there is an underlying pattern that annoys me too. There are literally thousands of people working in innovative transportation ideas, why is the barely researched idea of a relative amateur like Musk receiving so much attention?
The same applies to the Soylent story: people who have been working on the problem for decades are being ignored in favor of self-promoting entrepreneurs who's ideas lack depth.
The great irony is that the cheerleaders for these entrepreneurs are the same people that bitch about the lack of scientific knowledge in politicians and the lack of attention for science in general.
I can perfectly understand that this pisses people of who have been diligently working on these problems for decades.
the problem w/ casually describing it as a "marketing problem" is it completely excuses both entrepreneurial excess & the whole Valley hype thing. sure, there should be an onus on people to present/market their ideas well, but also on the public to be a little more skeptical of wild & unfounded claims.
[1] It's really impressive how they managed to create such interest around a product idea, with people describing it as innovative and disruptive, when you've been able to walk into any drugstore and buy identical (but better researched and quality assured) products off the shelf.
I would assume there are thousands of other areas like this where some "better" version never sees the light of day.
It's possible and maybe even easier to have truly breakthrough ideas if you're coming from a different field. You can always catch up on all the knowledge required to execute your idea later.
And yes, often you'll find out that your idea wasn't so great. But at least you didn't dismiss it as out of hand because you didn't come across it in your years of experience in the field.
Also, he seems to acknowledge the fact that he was standing on the shoulders of giants:
But one thing is clear: before attempting to create something new, it is vital to have a good appreciation of everything that already exists in this field. I myself have had many experiences confirming this to be so.
In particular, some parts of this article are just way way off base, e.g.:
> Tesla’s train energy consumption numbers do not pass a sanity check, which suggests either reckless disregard for the research or fraud. I wouldn’t put either past Musk: the lack of references is consistent with the former, and the fact that Musk’s current primary endeavor is a car company is consistent with the latter
and
> I write this to point out that, in the US, people will treat any crank seriously if he has enough money or enough prowess in another field.
The article would have been much stronger if it'd left ego and silly ad hominem out of it and reported on facts alone.
I also have concerns about the costings: the Hyperloop report didn't give sufficient justifications for any of them. Yet I assume they didn't just pluck them out of thin air either. We really need to know how they were calculated before we can do a more critical analysis of them or someone should try and come up with their own rigorous cost projections. We can go back and forth all day saying it seems too low until someone actually definitely proves it.
In particular, comparing Musk's projected costs for, e.g., viaducts to how much the government says they cost is almost definitely a poor metric since, after all, exactly the same could have been said for Musk's cost projections for rocket-powered spaceflight.
Whether or not the idea is valid is irrelevant - the fact that Elon Musk is proposing it does lend it some additional weight - with Space X and to a lesser extent Tesla, he has gone into an existing market, taken a step back, rethought things from the ground up, and re-written the book on how much it costs to do things.
I don't know if Hyperloop is as technically feasible and cost effective as it looks, I don't know if any government would have the courage to go in that direction, but I do know that it isn't going to get anywhere with good balanced debate on the technical merits of the proposed solution and ad hominem rubbish just gets in the way of that.
> Tesla’s train energy consumption numbers do not pass a sanity check, which suggests either reckless disregard for the research or fraud. I wouldn’t put either past Musk: the lack of references is consistent with the former, and the fact that Musk’s current primary endeavor is a car company is consistent with the latter
If the blog post's claims are correct - and the numbers in it seem to have a much more solid basis in fact than anything Elon Musk's come up with - then even a simple back-of-the-envelope calculation should've been enough to show his power consumption figures for high-speed rail are impossibly high. The trains are simply incapable of using that much power.
> If a famous question could be solved in ten pages, it probably wouldn’t still be open.
Which of course isn't saying that it's impossible, but that claiming it to be so requires overwhelming proof.
Hyperloop seems like an interesting idea, and certainly worth some investigation and research (as is, any proposal and idea). But large scale hand waving and dismissals of the problems as ad hominem attacks don't help lend an air of legitimacy.
My personal view? I find it interesting that he proposed this, but initially didn't want to do any of the development or payment himself. That doesn't sound like someone who truly believes in their "vision".
Why does this guy hate Elon so much?
Jobs-effect again and again.
Anyway, I have read the Hyperloop pdf end to end and I think it's great. I don't agree with this author at all that Elon Musk's endeavours distract from improving existing technology. Nor do I think that improving existing technology is as important as inventing new potentially disruptive technology in general.
People are fans of Musk because he succeeds and delivers in the face of spineless critics like this one. Just as people were fans of Jobs as he reintroduced quality into consumer electronics succesfully.
Did we read the same article? I read a rant, sprinkled with lots of verifiable facts that gave strong arguments why this Hyperloop idea won't fly.
For a rebuttal, I would expect claims that his sources are incorrect, that his calculations are incorrect, or that the conclusions he draws from those calculations are incorrect. Arguing that the author ranted too much is not sufficient for me.
For example, what's wrong with his claim that people would get seasick in this thing? If there's nothing wrong with that claim, what's wrong with his claim that that is a show stopper? Similarly, wants wrong with his arguments about the low capacity of this design?
Feel free to add some rantiness, but keep the fraction of content as least as high as this article, please.
And, by the way, I do not think this article says Elon Musk does nothing good; it just claims this idea of Elon Musk is not a good one because it is highly unlikely that it is possible to fix all of its problems. For example, one can straighten the trajectory, but then, costs would balloon to be at least on par with the existing high speed rail system.
His verifiable criticisms of the Hyperloop, they're probably true, good chance that people would get seasick in it, and that the capsules are too small and that corrections for this might make the project financially infeasible.
Not sure how that's relevant though.
Even if this project instead of 10 billion is more like the high speed train and would cost more like 100 billion, even if it was more expensive. Even if people could get sick in it.
Wouldn't it still be an interesting idea worth investigating? Wouldn't it be possible these are hurdles we could overcome? Elon Musk seems to think they are, and Elon Musk has a PhD in overcoming hurdles..
Personally, I find it questionable that an automobile entrepreneur is choosing to publicize this concept but invest nothing into building it himself, as if to spread FUD about high speed rail. Calling Musk out for that and for not showing his work when it comes to costs and numbers is appropriate whether or not it offends your hero worship.
He compares hyperloop with the smoothest mode of transportation invented, and says it will fail because it doesn't meet it's standard. Why not compare it to flying planes or sailing boats? Or riding a Marshrutka in Ukraine?
As for the low capacity - the critique's author says Hyperloop can handle 3 times less passengers per hour. But forgots to mention that you could buy more than 3 HL lanes for the cost of one HSR lane (if I remember correctly).
Getting sick at sea is OK because you have room to vomit in a sanitary way. Hyperloop gives no such concession.
Unless the proposed HSR involves moving everyone in California to Spain and using theirs he is the one who is "engaged in fraud or just being dodgy" as he likes to put it according to actual studies of the proposed system energy consumption go as high as 6.5 MJ per passenger KM. As Musk leads with in his document the proposed system is one of the worst HSRs energy and performance wise, quoting the best numbers in existence do not make a compelling counter argument.
Only if you assume that all the trains will be almost completely empty. I don't know about the US, but I've travelled on some odd routes at low-traffic hours in the UK and it's really fucking rare to see a train with as little as 10% occupancy because the rail companies don't run them.
Come to think of it, most of that was on relatively local lines that Hyperloop's not designed to replace anyway.
Though, there are also important questions he raises about Elon Musk: whether he has a conflict of interest as an automobile executive and why he is releasing white papers spreading FUD about rail projects without investing in the hyperloop project himself. The thought that Musk is a disinterested genius who does everything out of the goodness of his heart is a little naive, and the way people overreact when that's called into question says a lot.
As for Musk's character and intentions, I think he's been forthcoming in enough interviews[1] as to his reasons for starting his multiple current ventures (Tesla, SpaceX, Solar City). I don't believe his actions have contradicted his words in this respect, so for someone to attribute intentions to him that go against those statements and be believed, the burden of proof is on them.
[1]: I don't have the links on hand, but he's talked about how after Paypal he didn't *have* to do anything, being wealthy, so decided to focus on a few major areas he thought major contributions to the future of humanity could be made, to his best judgement. Those being cheap solar power, electric cars, and colonizing other planets.I write this to point out that, in the US, people will treat any crank seriously if he has enough money or enough prowess in another field. A sufficiently rich person is surrounded by sycophants and stenographers who won’t check his numbers against anything.
The problem is the article's criticisms aren't categorical. He doesn't apply the same standards he demands of Elon et all to his own claims.
It's sad, because clearly the guy is well informed on public transit projects, but there's no reason for him to descend into ad homs and his own pet psychoanalysis of Elon Musk.
Critics will always have an audience in the envious and the shadenfreudencia.
Implementing them: yes, that's harder, and most transit ideas fall down at that stage. Implementing them in a way that comes anywhere near the original optimistic projections is even harder (see: maglev).
But people have already pointed out that this is merely an idea and should be treated as such. Though a town with money is sort of like a mule with a spinning wheel...
Didn't he already make all the living he needs and now just does whatever he likes?
However if one has to choose what to spend time on, it is prudent to filter, and for blatant subjectivity to be used as one such filter, as it is reasonable to consider it likely that arguments made by someone who is so obviously biased against someone in the first place is more likely to be careless about the arguments he makes against their ideas.
So a a time saving exercise, it is absolutely relevant to consider other factors than the argument itself.
And yes, it is imperfect and will result in a lot of people discounting valid concerns.
Author is:
- unfriendly towards Elon Musk
- unfriendly towards people who voice ideas of what the author thinks is not their area of expertise in general.
- fond of high speed trains.
- thinking that Elon Musk wants to kill trains to sell more cars.
... oh yeah, and he has some concerns about Hyperloop estimates. Mainly that cost and disadvantages are underestimated.
Also somehow author managed to overlooked the fact that Elon Musk delivered some stuff to International Space Station, most likely at fraction of NASA cost which consist of very experienced people.
If experienced specialist tells that something in his area of expertise can be done. He's most likely right. If he says something can't be done, there's a fair chance he's wrong.
1. The weight of the train and the hyperloop capsules are the same
2. The construction methods employed are identical.
But they're not! Average train car weight (if they have to comply with FRA regulations) should be in the 60 ton range. https://www.ebbc.org/rail/fra.html and http://uk.answers.yahoo.com/question/index?qid=2006082807531... Average train car length is betwen 60 and 80 feet so we'll go with 80.
60 tons / 80 feet = 1500lbs/foot. In the case that a non-FRA compliant car can be used, that number SHOULD drop to about 750lbs/foot.
The hyperloop cars are speculated to be 16.5 tons and 28.5 tons each. No hard numbers on length but if you assume 3ft per passenger and 28 total (14 per side) and add a bit of room for the other stuff, you can come up with 14 * 3+15=57 feet or for three cars, 3 * 20+15=75 feet.
33,000lbs / 57 feet = 578lbs/ft. 57,000lbs / 75 feet = 760lbs/ft
So it looks like the big-case hyperloop will weigh about the same as the best-case high speed rail.
Now let's analyze the support mechanism. Trains run on rails (two of them) and they weigh ~100 lbs per foot and are around 3" wide and 6" tall. These rails need to be very precisely supported both side-to-side and up-and-down especially if the trains are going to run at 200+ MPH. For viaduct you've got to build the bridge, then put down the ties, then put rail on top of those, fasten it down, etc. Ties are in the range of 6-8" thick and then there's the ballast (rocks) which aren't light either and which are generally required to keep the ties from moving. On bridges (viaduct) you might do something newer and fancier but I wouldn't count on it here in the US. Overall you've got at least 200lbs/foot for the rails and I might guess another 500-1500lbs/foot for the ties and ballast and such. Rock weighs ~150lbs/cuft and so does concrete so if your ties + ballast are a foot thick and 8 feet wide (rails are 4'8" plus 20" extra on the sides) that's 1200lbs/foot.
Hyperloop runs in a 7.5 foot diameter tube with a 0.8in thick wall. 7.5 * 12 * pi * 0.8=226 square inches cross section. Or a foot of it has 2712 cubic inches of steel. At 0.283lbs/cu-in that comes out to be 767lbs/foot. Because it's pipe (which has excellent structural geometry) it is self-supporting and thus all you really have to do is get the pipe properly supported on top of the pylons, weld two sections together and you're done.
Here's the last part. Hyperloop cars will be at least a mile apart. That means the system can be designed to support just one of them per pylon. Train cars will be 3 feet apart, and thus the viaducts have to support 1500lbs/foot * 80 feet per car * 10 cars = 600 tons. Versus the hyperloop car weights of 16.5 tons or 28.5 tons.
So these two systems are mildly different in terms of their car weights but dramatically different in terms of the overall structural requirements and design to meet those structural requirements. Train track is heavy and train cars are heavy and trains are fairly dense (due to their length). Hyperloop cars are about half as heavy and hyperloop track is half as heavy and hyperloop support densities are only about half versus rail. 0.5 * 0.5 * 0.5 = 0.125 or 12.5% which isn't terribly far off from the 10% number that the Hyperloop is quoted to cost versus the high speed rail system.
TL;DR: Cut track weight by half, car weight by half, and total support weight by half and you get 0.125 which is suspiciously close to 0.10, the number that the article author had such a problem with.
EDIT1: formatting
EDIT2: tl;dr
The capacity of the structure is not just limited to the weight of the revenue vehicles, the structure needs to handle other loads it may encounter over the its useful life, such as snow (probably not much of an issue in central/southern CA), water (if the tunnel leaks) and maintenance vehicles (which will likely be significantly heavier than the passenger cars since they will have to be self-propelled).
then put down the ties, then put rail on top of those, fasten it down, etc. Ties are in the range of 6-8" thick and then there's the ballast (rocks) which aren't light either and which are generally required to keep the ties from moving.
You don't need ballast & tie track on structures.
In any event, cutting the material weights in half (even if you can, which is doubtful) does not automatically cut your costs by 90 percent. You still have the environmental process, you still have NIMBYs, you still have construction mobilization costs, etc.
I would argue that since the tube sections would all be pre-fab that means that the installation cost of the tube would be really small. Rail installation costs are no joke due to the need to precisely align horizontally and vertically the two rails.
You can make tube in 50ft sections and ship them via truck without needing any special permitting and given that the highway runs right next to the planned route, the pre-fab notion is quite a good one.
The hyperloop sections would also need to be precisely aligned.
You can make tube in 50ft sections and ship them via truck without needing any special permitting
But you may need special routing for those trucks to allow overhead clearance and turn radii, and you may need to build temporary roads for access to the installation site. There are lots of little things that tend to add up that are ignored in the whitepaper. You may be able to reduce costs by a few percent, but 90% is not a figure that I can take all that seriously.
If you wanted to do the 11ft you would need a low-boy trailer to avoid height permitting and you would need "wide load" signs for the trucks individually but no lead/chase vehicles.
The tube joining/welding/grinding jig could be 40ft (or 200 ft or more) long and fit inside the already assembled tube AND the to-be-welded tube. Precision alignment could be done via movable clamps. Once the tube is held in place via the jig it can be welded via a number of methods (friction stir, friction, MIG, TIG or SMAW) inside, outside or both.
You are not going to give yourself 6-inches of clearance for a component that weighs (using your numbers) 19.2 tons, that pipe is going on a flatbed. You also have to allow room for tie-downs, flanges, support blocks, etc. You also have to account for bridge weight limits.
I'm not saying this isn't doable (the Big Dig was able to truck in 100 ft soldier piles, although they had to do it at night), it's just that it often takes extra planning and work which increases costs.
The tube joining/welding/grinding jig could be 40ft (or 200 ft or more) long and fit inside the already assembled tube AND the to-be-welded tube.
Are you basing this on something that already exists, or is this something you are proposing?
If it's possible to make two tunnel boring machines meet at the middle of the English channel with the starting points separated by some 20 miles, then it's entirely possible to build a pipe-section-holding jig which can ensure precise alignment. I probably can't write a check for one and have it in a year (partly because I don't have $5mm, also because the plans don't exist yet) but to suggest that it would take more than three years to design, build and verify such a machine is a bit extreme. You could probably do it in a year or less provided that you're willing to pay more.
The machine as a whole doesn't exist yet but all the various component pieces of it do and they're all COTS parts. It's part tunnel boring machine (http://en.wikipedia.org/wiki/Tunnel_boring_machine) part orbital welder (http://www.mecomachineandfab.com/public/images/photos/orbita...) and the rest is "glue."
Make it 300 feet long so that it's always resting on pipe that's already affixed at two separate pylons and so that it doesn't deflect the pipe on either side of the joint it's about to make. An external crane (or if you get clever, one built onto the TBM/welder rig) lifts the pipe up, the jig grabs hold of it, positions it, and then makes the weld. Let the machine advance slightly and x-ray the entire weld for QA/QC and provided it passes, advance the machine to do the next section.
If you wanted me to make one of these for you I'd probably quote $500k-$1mm for the initial research including a small prototype (10-20" diameter) and I would guess (+- 50%) $10mm for the big one.
I built an semi-automated package dimensioner and barcode reader for about $5k in parts plus my time The NRE was probably around $40k. A fully automated one (including transport) starts at something like $80k. The company I worked for then might have lost money on the first one (only if you look at opportunity cost) but by the time they build three, they've saved at least $150k. Three of them plus the employees to operate them would have a similar throughput, higher dimensional capacity and better exception handling (what do you do with a damaged package? Or one that's leaking?) than the one fully automated system. An $80k system that can do 10x what your needs are is definitely more expensive even if the per-unit costs are the same because you're paying for idle time.
Elon Musk isn't going to call me up and ask me to build that system for him. But if he did I wouldn't have too many problems making it happen. The difficulty isn't making the machine, it's finding someone with the constitution to ride out the periods of uncertainty and doubt while all the bugs are being ironed out.
EDIT: When I've suggested that I could do the research and build a 10-20" prototype I'm referring just to the pipe positioning jig + orbital welding system. Not a small-scale hyperloop. That would be quite insane. Just a precision alignment jig and associated welding equipment to do the final fit and assembly of the pre-fabricated pieces.
For example:
If it's possible to make two tunnel boring machines meet at the middle of the English channel with the starting points separated by some 20 miles, then it's entirely possible to build a pipe-section-holding jig which can ensure precise alignment.
Of course it's possible, I've never claimed that it wasn't. The issue isn't "is it possible" it's "can it be done at less cost than current proposals." History shows numerous examples of new construction techniques that worked great on paper, but had significant implementation flaws - for example soil freezing was supposed to be a panecea on the Central Artery/Tunnel project, but there were a ton of problems in the implementation and unexpected results that needed to be dealth with. Even your Channel Tunnel example proves this point - it used a lot of innovative technology and it came in late and over 80% over budget.
You talk about a welding rig that doesn't exist as a fait accompli. You wrote "My point was to say that it's entirely possible to fit that size of a tube onto a semi trailer with no hardship at all.' - that's bull, I've seen crews have a difficult time moving smaller and lighter pieces off and on semis. "No wide corners, no permits, no height restrictions, none of that" - really? You're familiar with every possible street route along the proposed Hyperlink corridor? Because if a truck gets stuck someplace (it happens: http://www.wwlp.com/dpp/news/local/hampden/truck-stuck-at-ho... ) the project is in for a bad time. And again, we haven't even begun to address NIMBY issues.
That said (and I'm being serious here) if you have the chops to make solutions like this work, you need to be working (or consulting) for the big engineering firms like AECOM, PB, CH2M Hill, Jacobs, etc. Your ideas could revolutionize the industry.
The difficulty isn't making the machine, it's finding someone with the constitution to ride out the periods of uncertainty and doubt while all the bugs are being ironed out.
Exactly. That period is called "final design and construction." It's been the death of many construction and A&E firms.
As far as loading tubes go, you're likely going to build a tube rolling facility. These kinds of places tend to have overhead cranes. Big ones. Cranes that can grab the tube on both ends and thus have precise control over it. Most likely the loading would be done "indoors" so weather is mostly factored out. Building semi-circular restraints that grab the tube in 3-5 places along the 50ft length is done easily enough with a water-jet or you could roll a pipe into a semi-circle and weld supports to it. Once you have the custom trailer done it's relatively straightforward. You'd build the infrastructure to handle this in a highly automated fashion, similar to how container ships get loaded and unloaded. ~350 miles is 36,960 50ft sections of tube, double it since we're doing double-wide. If you know you need that much at the beginning there's a lot of work that can be done to make the whole thing reasonably efficient and cost effective.
I don't understand why you're expanding the scope to NIMBY or access roads or stuck trucks (locate the plant near the freeway) or any of this. I was talking specifically about the loading and unloading of pipe and making a jig to hold said pipe for precise welding.
Again, when I said "The difficulty isn't making the machine, it's finding someone with the constitution to ride out the periods of uncertainty and doubt while all the bugs are being ironed out." I'm referring only to building the alignment/welding machine, not the entire Hyperloop system. I realize that building the whole thing is immensely more difficult than building the alignment/welding jig. But we're inventing very little new stuff here, mostly repurposing things or making incremental changes.
All the "final design and construction" that you're talking about has the same risks and problems for the HSR as for the Hyperloop. If I have to be exposed to an 80% cost overrun I'd rather it was on a $5bn or $7.5bn project rather than an $80bn one. Maybe Hyperloop even has a 300% cost overrun and somehow the HSR project could come in 25% under budget. Hyperloop would then be (assuming the bigger version) $22.5bn versus the rail at $60bn.
The reason I don't work at a big engineering firm is that I couldn't get hired in at a senior enough level to actually get anything done. So I work for small companies. Thus far my track record is excellent but it would probably take me another 10-15 years for me to have enough successes at difficult projects for people to stop assuming it's a fluke. And by then I might not be too interested in risking my career on every project I work on.
This is why startups are even possible. The risk aversion of senior management makes it possible for people who are too young and too dumb to know that something's "impossible" to make it happen. If you've got any ideas how I could get hired at a big construction firm at a senior level I'm all ears.
There is all kinds of crazy stuff out there: https://www.youtube.com/watch?v=E0O78AyDixY
They're using a $45mm, 45 foot diameter TBM in Miami right now that's 450 feet long, has the ability to erect concrete rings inside of the machine, and can exert crazy pressure on the rock face. http://www.portofmiamitunnel.com/faqs/tunnel-boring-machine/
I'm suggesting something with less challenging specs and suggesting it could be built for less money. I don't think it's unreasonable.
In the comments to his blog post, the OP disputes that lighter weight is going to lead to significantly lower pylon cost. I didn't look through his references, but he also has an update showing how assuming that pylon costs are going to be linear in the weight is not consistent with the hyperloop document itself.
I had to reread the update a few times, but the argument is: the proposal contains two versions, for passengers and for cars. The car version will weigh more and cost more, but the cost increase is much less percentage-wise than the weight increase, so the hyperloop designers themselves don't believe that pylon will be linear in the weight.
As I said elsewhere, this is why references are not just a formality. If the designers had explained where they got their cost estimates from, we could still argue about their accuracy, but we wouldn't have to speculate where they came from.
Of course, this would have rather poor capacity, but that's a problem with the hyperloop as well. It would also be slower at maybe 200 - 250 MPH, lowering capacity further.
But if someone claimed they could simply do a 250mph light rail at drastically lower cost, people would necessarily be skeptical. Adding a bunch of really interesting high speed tech on top, shouldn't change that claim much. About the one way I can see it should change the skepticism is if the increased speed increases capacity sufficiently. Which seems not to be the case.
2) I would expect that wind pressure on a tube is higher than on a rail with an occasional train on it. If so, the supports need to be designed to handle that higher load.
3) I think higher speed trains going through a bend in the track exert higher forces per kg of train than slower speed trains. Again, if so, the design will have to accommodate for that.
4) I don't see how that 0.5^3 makes sense. If both track and train are half the weight, my conclusion would be "total structure to lift is half the weight", not "total structure to lift is a quarter the weight".
I am not an engineer, so corrections welcome.
On the other hand, I think he has some good points regarding the cost numbers. If pylons have all the advantages that Musk claims then why aren't we all getting around city on monorails?
I love HSR. But I also think we as a species are capable of much, much, much more than we're currently accomplishing. And much of the reason we're stuck using slow, uninspiring, and polluting technology from yester-year is a lack of public will.
So to the naysayers: if you want to harp on some bold proposal to do something great, pretend it's 1961 and someone told you about sending men to the moon and back. Pretend it was 1948 and someone proposed making trains that went 90 mph. Pretend it was 1850 and someone proposed linking Paddington and Farringdon using a massive tunnel buried deep underground. Real things change all the time. Technology can make problems go away. Bold proposals such as Musk's -- proposals that are the good-faith effort of someone who is ultra-competent and with a lot of social and financial capital -- are proposals that need to be celebrated and encouraged.
Doing new things well is orders of magnitude more difficult than doing that which has been done before. If you've never followed-through on a crazy and bold idea, please temper your critique of those who have.
https://en.wikipedia.org/wiki/File:Trans-Alaska_Pipeline_Sys...
A high-speed railway needs to be flat, so it needs tall pylons to support it above uneven terrain:
https://en.wikipedia.org/wiki/File:SNCF_TGV_Duplex_Viaduc_de...
https://en.wikipedia.org/wiki/File:Millau_Viaduct_constructi...
"Security checks"? Why would Hyperloop require any more security checks than the HSR? If anything, you'd expect security to be faster for a constant stream of departures, vs 1000+ passengers bunched together for a train.
(Or you could be sensible like the French, Japanese, Germans and Chinese and dispense with any train-related security theatre entirely, but that would probably be too much to ask in the land of the free and the home of the scared.)
The earth has become small, and on it hops the last man, who makes everything small. His race is as ineradicable as the flea; the last man lives longest.
'We have invented happiness,'say the last men, and they blink. They have left the regions where it was hard to live, for one needs warmth. One still loves one's neighbor and rubs against him, for one needs warmth...
I see Musk as something akin to Nietzsche's superman - and this chap, the detractor, the denigrator, the naysayer, is his last man.
Musk owns a space exploration company that is flying regular commercial missions, yet OP thinks that Musk has made elementary mistakes in his physics calculations. SpaceX are currently building a passenger spacecraft, but OP thinks that nobody has factored the effect of G forces on passengers into the design. They have reduced the cost of putting mass into orbit by an order of magnitude, but OP deigns to assess the validity of Musk's cost estimates.
Frankly, who the fuck is he to tell Elon Musk what is possible? Musk has degrees in both economics and applied physics. He has done the "impossible" in three industries and is an epoch-defining figure in electronic payments, space exploration and the motor industry. Musk isn't some crackpot with a big bank balance, he's a genius with an astonishing track record of revolutionising established industries from the outside, by ignoring old assumptions about what is possible.
Hyperloop might succeed or fail, but I genuinely can't think of a single person who has ever lived who might be better qualified to make that judgement than Elon Musk.