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Well, that's fairly hyperbolic. It wasn't near self-evidently fantastical, unless you base that entirely on political willingness.

As for what you thought made it fantastical, I would love to hear a short list. My last understanding of it was that there wasn't anything specifically physical or technical that prevented it from being possible (albeit requiring more real-world testing), and there was at least some effort put into addressing the implementation details. If there are portions that are actually impossible rather than just unlikely I would rather know than remain ignorant.



No, it was fantastical. For instance: the cost estimates Musk provided were premised on advancements in tunnel drilling and elevated track construction costs that would have revolutionized all of civil engineering, not just hyperlooping.


"Ahlborn says, and Musk's cost estimate of $6-10 billion for a 400-mile stretch of Hyperloop is on point, based on the team's work."

Obviously this is a fluff piece, and he has incentive to not play up any problems with the budget, but it's stated there openly. You've stated the opposite, since I don't have evidence from either of you, why exactly should I consider your opinion more worthy than a group of many competent engineers?


http://pedestrianobservations.wordpress.com/2013/08/13/loopy...

Musk's viaduct costs, for instance, were 1/10th those of California's HSR. His premise is that he can decimate the HSR cost.

Obviously that is a comparison that is relevant for LA-SF, but potentially not for Houston-Austin. Which I acknowledged upthread. As did the "many competent engineers" in this piece.


> Musk's viaduct costs, for instance, were 1/10th those of California's HSR.

ISTR -- and I may be mistaken -- that a significant portion of the underestimation there wasn't engineering-related, but real-estate related, in that costs of acquiring the land for the footprint was low-balled or ignored.


I also seem to remember that, and I believe Musk attributed so much savings to it because there was very little right of way that needed to be worked out, he was going to put it in the median of I-80. That reduces the theoretical cost quite a bit.

I think that's the goal of the company doing this, to test the feasibility of the design in more detail. It's also why I'm inclined to give them some weight in their assessment of the costs. But not too much. If I was an investor in some of this testing, I would want to go over their cost assessments with a fine toothed comb. It does seem this is one of the biggest unknowns in the proposal, and it's also one of the things that could change the most depending on where it's implemented, making it hard to make definite statements about.


> I also seem to remember that, and I believe Musk attributed so much savings to it because there was very little right of way that needed to be worked out, he was going to put it in the median of I-80.

A casual glance at a map of where I-80 runs might suggest that that wasn't quite right.


That's right, it was I-5. For some reason I often confuse them, even though it's obvious one is north/south and one is east/west. I'm on portions of I-80 about once a month, but I-5 generally no more than once a year.


Yes, it was I-5 of course. Also it is easier to acquire rights to land when you don't divide the land but rather have pylons.


It's tough to seem to remember something about a source that is contradicted in the source itself. I think you should start by reading the link, and then opine on it.


No, it's not tough to seem to remember anything, human memory is very fallible. That's why I prefaced the statement with that bit, because I was in no way sure. That said, my memory wasn't that bad. Here's what I was slightly misremembering from the proposal:

By building it on pylons, you can almost entirely avoid the need to buy land by following alongside the mostly very straight California Interstate 5 highway, with only minor deviations when the highway makes a sharp turn. [1]

So it's I-5, not i-80, and it's beside the highway, not in the median. I'm not sure how either of those mistakes affect the point I was trying to make to the degree it's not worth addressing, so I'm unsure why you used a rhetorical tactic instead of just correcting (since you obviously knew it was incorrect) and addressing that point, but that's your prerogative.

1: https://www.teslamotors.com/sites/default/files/blog_images/...


You're not addressing the source I provided; in effect, you're affirming the consequent in this argument.


We are talking at cross points. My, and I believe others, issue with the source you posted is that after stating that the actual central-valley land is cheap, it ignores the rights-of-way costs, which is where many believe a lot of the cost savings really are. It's hard to be definitive with the sources I've seen so far, because while they are all happy to post numbers for costs, few seem willing to break those down into what the cost is for, and since we are talking about different types of structures, it's hard to say whether the comparisons apply well.

As an example, your source states that the tube weight (for the larger plan) would be up to twice a train weight and thus would not cost less to build, and links to his own listing of train weights which are, as he states "To the best of my ability, I've tried to give dry weights, without passengers." That seems to imply that this is also without cargo. To my knowledge, most rail in the Western U.S. is built to handle cargo, and I imagine that's much heavier than commuter trains, and that could greatly affect building cost (to be clear the hyperloop could move cargo as well, but the relative dynamic weight of the cars to the static tube weight is much lower, yielding a smaller weight range). That leaves me without enough information to assess whether this is even a fair and valid comparison to make. There are other important factors as well, such as the weight of the hyperloop cars traveling through the tube that would need to be addressed if the tube weight was more favorable to train weight.

What this comes down to is that with respect to building cost, your source leaves me less that assured that it has done more that a cursory review of the information and applied possibly inaccurate numbers and assumptions. There's just too many details that are left out to know. At the same time, the original hyperloop proposal was lean on specifics as well. I guess the difference is that I don't see this situation as painting either stance as "fantastical," there's just not enough concrete information presented for me to know either way.

1: http://pedestrianobservations.wordpress.com/2012/03/13/table...


> "To my knowledge, most rail in the Western U.S. is built to handle cargo"

Definetly true.

> "and I imagine that's much heavier than commuter trains"

Also definetly true. A double-decker Amtrak passenger car clocks in at around 70 tons. Freight cars can be an order of magnitude heavier.


This is addressed, at least somewhat, in the source I just cited.


Pedantic, but decimate is to reduce by one tenth, not reduce to one tenth, as it is more commonly used.


Pedantic, but "decimate" has the primary meaning of "reduce by a large percentage", based on the historical reference to a particular Roman practice of killing 1 in 10 of a group as a means of collective punishment; it does not generally (i.e., outside of the context of that specific historical practice) mean to reduce either by or to one tenth.


This is all my fault and I accept and will now wallow in my wrongness.


That's what you get for italicizing words!


That's lovely but your post isn't really contributing. bmelton was pointing out an actual misuse* . "Decimate" can mean either large percentage or the traditional 10% drop, it does not mean 90% drop. Your post moves into pointless word argument territory.

* or perhaps a pun masquerading as misuse in a way that invites 'correction', an utterly terrifying category of pun I hadn't even considered before


> That's lovely but your post isn't really contributing.

To the extent that is true, I kind of thought I addressed that with the first word of the post.

> bmelton was pointing out an actual misuse

And I was pointing out an actual error in bmelton's description of the actual misuse (which -- see below -- is repeated in your description.)

> "Decimate" can mean either large percentage or the traditional 10% drop

No, it can't. It can mean reducing by a large percentage, or it can be reference to actually killing 10% of a group of people as a form of collective punishment. It does not mean reduce by 10% in any general sense any more than it means reduce to 10% in any general sense (though the latter is more likely to be within its general meaning than the former.)

> Your post moves into pointless word argument territory.

Well, I would say that tptacek's point was entirely clear despite the misuse, and that both bmelton and my responses were provided with accurate warnings by their submitters as being pedantic ("overly concerned with formal rules and trivial points of learning.")


While I acknowledge, and generally believe in the evolution of language, I refuse to succumb to the trend of colloquial usage coming to mean the opposite of a word's original intent.

To illustrate the point better, "literally" has now also been defined to mean "figuratively" in the common parlance, which means that, sadly, there is no appropriate word for literally that is unambiguous.

Similarly so with decimate. Its originalist intent is to reduce by one tenth, so, colloquial adoption aside, I reject any definition that resembles its polar opposite.

Clearly, the colloquial usage, as tptacek has done, is acceptable to many, but if words are intended to actually mean things, instead of just send an appropriate contextual vibe, then there should be some degree of rigidity to language that pushes back against its less meaningful and more ambiguous adoption.


Look, we can all just let Garner kill this silly discussion for us:

https://www.dropbox.com/s/igqynqcdqrj86mk/Screenshot%202014-...

I shouldn't have used the word. It's a dumb word. Direct ire my way.


No malice intended with the correction, nor any ire as a consequence of its use.

I'm just that special kind of internet-goer that appreciates correction, and expects others to do the same. Apologies for having belabored the point.


I apologize for using the word. :)


That may be, but the parallel emphasis in tptacek's specific usage make it pretty clear that he was using the term literally.


If we're talking about ancient Latin then yes. If we're talking about modern English then no. As well argue that "beef" refers to the entire cow rather than just its meat.


a) the HSR is a political boondoggle that California will suffer with paying for decades even if it does get done.

b) if Musk is so confident on his ability to deliver, let private industry take the risk and put it up.

Its bad enough we have to foot the bill for political showmanship and braggarts, we don't need to be footing the bill for untested technology by private interest who profess extreme confidence, but seemingly not enough to back with their own money. If he will, more power to him. Love Space X, don't care for this idea other than the out of this world feel


Please describe in what way CAHSR is a boondoggle.


The cost to build one mile of 6 lane interstate in an urban area is estimated at 11 million dollars per mile. If you look at the estimated cost for the hyperloop, it seems to come out at around 25 million per mile. This isn't outside the realm of possibility at all, just a little more than twice that of traditional methods.


The hyperloop isn't a 6-lane interstate. It's an elevated track, some of it tunneled through rock.


The point I was making is that considering the huge upside, merely double the cost of a traditional highway seems like a very reasonable price.


It's not "double the cost". Nobody knows how much it's going to cost, but we know it costs more than Musk says it does.


11 million dollars per mile does not seem accurate. They recently widened the Turnpike in NJ from 6 to 12 lanes over a 35 mile stretch, and it cost $2.3 billion. That's $65 million per mile. And that was considered a successful project.

http://www.northjersey.com/news/nj-turnpike-widening-set-to-...


So, it's not fantastical, it's ambitious... Fantasy implies an impossibility.


Once again: I chose the word fantastical somewhat carefully and think the evidence bears it out. It's not an ambitious cost estimate; it's simply unrealistic.


A), ambitious and unrealistic are not mutually exclusive. It was ambitious and unrealistic to attempt a moon landing in under a decade.

B) Again, I believe fantastical implies a rational person would think it highly improbably. I'm a rational person, but so is Elon Musk; what appears fantastical to me appears ambitious to someone with a better understanding of the situation. I suspect this would apply to you, too.


> A), ambitious and unrealistic are not mutually exclusive. It was ambitious and unrealistic to attempt a moon landing in under a decade.

That's absolutely not true. It was ambitious and totally realistic to attempt a moon landing in 10 years.

Kennedy only selected that goal after von Braun said that it could be done "by 1967/68". He even added an extra two years of padding, just in case von Braun was being optimistic.

Anyone who knew anything about space flight knew that Kennedy's goal was achievable. In fact, some thought that von Braun was gold-plating the program unnecessarily. McDonnell did some engineering studies for landing one man on the moon using Gemini and a Saturn C-3 (about half the payload capacity of a Saturn V).

If 90% of civil engineers would say in 2013 that Elon Musks hyperloop plan was realistic, then it would be where the moon landing was in 1961. But they wouldn't. In comparison to the moon landing, Elon Musk's hyperloop was wildly unrealistic.


"Because Elon Musk" isn't a real argument, but as this thread shows, it is routinely mistaken for one.


"Because consensus" hasn't been terribly great either, thought it is routinely mistaken for one. IMHO fantastical implies that it directly contradicts rationality, not common knowledge.


The "some effort" included a 3-stage FEA that I accomplished in less than one semester of study. And I'm a computer engineer, I don't even have a real mechanical or civil-engineering experience and I could tell that the FEA proposal in the paper was a complete joke.

You say there wasn't real world testing. I go further, there wasn't even a serious theoretical analysis of the proposed Hyperloop system.




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