#1: "We need some publicity. Maybe we can ride Hyperloop's hype coattails."
#2: "Yeah, we could simulate it and talk about the results in technical sounding but vague terms that we can't be meaningfully challenged on. But what do think will get more publicity, saying it will work or that it won't? There's plenty of latitude in the specs for us to end up with either."
#1: "That it will, of course. We want our customers to think they'll be validated by our software, not shot down. But make sure you provide a little advice so it's clear that we add value. And also hedge a bit so that just in case Hyperloop is a technical disaster, we don't look terrible."
#2: "Sounds good. I'll call Bloomberg and see if they have any spots available for vacuous puff pieces."
I'm under the distinct impression that the decision if the Hyperloop is built is less about technical details and more about project cost.
It's not like the engineers working with Elon Musk are taking a break from designing rockets - oh wait - The engineers at spaceX build rockets that go into orbit.
And freedom. If you commute with a hyperloop, can you stop by the grocery store on the way home? Not easily.
But beyond cost and freedom, there is practicality. For a while I wanted to take the bus to work, but it would take 4 hours to get there (including 10 miles walking) and only 30-40 minutes in a car. They would provide a bus to make it only 30-40 minutes if there were enough people like me to take the bus, but how do they know? They never asked.
Here are the directions the government-sponsored online tool gave me for how to commute to work (miles rounded up):
03:04AM - start walk 8 miles from home address,
05:59AM - arrive at bus stop,
06:01AM - start first leg of bus trip,
06:15AM - stop first leg of bus trip,
06:17AM - start second leg of bus trip,
06:38AM - stop first leg of bus trip,
06:38AM - start walk 2 miles from stop,
07:09AM - arrive at work
I could do that if I had a collapsible bike and could shower and change at work, but I can't (and won't).
One of the things I read about high speed city to city travel is related to commuting, not just business travel. But yes, I was changing the subject to public transportation, which I think is a serious problem in the U.S.
Would you really let that impact your decision as to whether to use a Scooter to get to work? It's too cliché to mention all of those people die going to work using other methods of transport.
I ride a Motorcycle because I enjoy it. However, there are many Londoners who use one primarily for commuting. It takes around 40 minutes on the tube to get to Central London from where I live, plus the wait time for a tube and the issue of whether you can actually get on it when one arrives.
I can do the same journey I can do in 20-25 minutes by motorbike. Because I can filter (lane split) the journey time is much more consistent than in a car and contributes less to congestion and has less impact on the environment.
While the level of safety will never be the same its quite clear that its a reasonable trade off. Especially if you live further from a tube station than I do.
As a former motorcycle rider: That doesn't work in the US (or at least not in Dallas, TX).
For one, drivers are pretty hostile to bike or motorcycle riders.
For another, look around on your commute. How many 2m tall vehicles are blocking your vision of the road and hurting your situational awareness?
Now imagine that a solid 70% of the vehicles on the road are 2m tall or more, most of those with blacked out window tint. That's Dallas, TX.
Not to mention that only something like 1 in 50 vehicles would probably qualify as compact. Most of the time you have large sedans, SUVs and trucks to share your lane with.
In the actual city (as opposed to the suburbs) you also have a large contingency of selfish, reckless drivers. Wether it's:
* People traveling 30MPH in a 40MPH zone in the left lane
* Sitting stopped for an extra minute when the signal turns green to chat at the driver next to them
* Turning in front of other vehicles across multiple lanes of traffic
* Aggressive Tailgating
* "Clipping" lane-changes
It's a different world. The average road speed is 45MPH+. I can't imagine going even an entire month lane-splitting in Dallas and not ending up in the hospital.
It would be great to speak to you 'offline', I think it would be really interesting to compare experiences.
A few points which I hope you might find interesting. London taxies are pretty tall (6ft easily) and there is no chance of being able to see over a London bus! It is a fairly common thing to think of Europeans countries as driving tiny, economical cars. However that isn't nearly as applicable in London as elsewhere in the UK and much of the rest of Europe.
The congestion charge for driving into central London is prohibitively expensive such that only those people who can afford it, driving almost SUV sized range rovers, or those who make a living from it driving vans, taxis or buses do it.
Our cities and road networks have evolved around streets and roads dating back to Roman times. They are rarely straight, often narrow and heavily congested. We have no concept of jaywalking and our pedestrian population universally appears to have a death wish.
The quality of driving in the UK in general is reasonably high, though I find it more variable in London possibly due to the number of foreign drivers.
Driver attitude to motorcyclists is interesting. Generally most allow us to get on with it, some are actively helpful and a small percentage attempt to stop you getting through. The last group generally don't succeed for long, even if I do have to get a little creative!
That being said, the average speed of traffic through rush hour London is 12mph so it's easy to see why skipping to the front of a few queues makes a big difference!
Do you seriously think that Musk 1) needs some cheap "publicity", or 2) he didn't do quite a bit of simulations before releasing the very first whitepaper?
Again, this guy is sending rockets to space - and back. He has a couple of thousand rocket scientists and physicists at his disposal. Ansys is just getting to conclusions they have achieved long ago.
> Do you seriously think that Musk 1) needs some cheap "publicity", or 2) he didn't do quite a bit of simulations before releasing the very first whitepaper?
The article makes it sounds like this somehow counters the criticism of the Hyperloop, but all the criticism I saw was of the cost estimates of the infrastructure, the utility of a route with the proposed termini, and the idea that a paper concept with no demonstrated prototype was a serious near-term alternative to high speed rail, while the issues this addresses is the basic viability of the "pod in a tube" mechanism (which it says is basically sound in outline -- but needs to be done in a different way than actually proposed in Musk's paper.)
So, it's basically a validation that the part was least criticized is probably basically viable in some form, though perhaps not the actual form proposed by Musk.
(And the one part of the pod-in-tube engineering that was seriously criticized -- the proposed mechanism for addressing thermal expansion over long stretches -- is also not addressed by this discussion.)
I'm not exactly impressed by this analysis. I don't recall anyone questioning whether putting a cylinder in a vacuum tube was possible, mainly that it would be horrendously difficult to design, build, tunnel, and reach the high safety margins required, relatively inefficient compared to the alternatives, and that there was lots and lots of hand waving over the real details.
They've simulated a vacuum tube, and found that it works.
If you'd actually described any relevant aspect of Hyperloop your criticism might have more credibility, as it stands it has none. Hyperloop is not a vacuum tube train, and the primary mechanism it relies on is non-trivial.
In your rush to point out the error he made about vacuum tubes, you missed his point, which is that the criticisms of the Musk plan don't revolve around the concept being infeasible to execute, but rather that the concept isn't cost-effective or, for that matter, nearly as customer-friendly as the proposal suggests.
Specific points that you'd want to address if you were purporting to rebut Hyperloop criticisms:
* Because Musk's plan can't leverage existing last-mile infrastructure the way HSRs do, it delivers riders from one very inconvenient location to another, adding 1-2 hours of additional transit time to SF-LA.
* Because (by Musk's own admission) destructive disruptions of his pod-in-tube runs are catastrophic in a way that they aren't with HSRs, his plan requires TSA-style airport security, adding an additional 15-30 minutes to every trip.
* The cost estimates for the Hyperloop captured only its capex costs and not its operating expenses, so that the per-ticket prices derived from its proposed cost bore no relation to its actual cost structure.
* That the tunneling and viaduct cost estimates given in the Hyperloop proposal were so low that they constituted a revolutionary breakthrough in urban planning and structural engineering in their own right; in other words, if he can dig a Hyperloop-capable tunnel for the price his plan suggests, or run an elevated tube as cheaply as he suggests, why waste time with Hyperloops? The answer would be that he can't do either of those things.
* That the routing he proposes, particularly with regards to mountain passes, are wildly optimistic, and that a realistic routing will result in a longer run and significantly increased costs.
* That the forces involved on passengers in the Hyperloop exceed the tolerances allowed for existing HSRs in ways that are likely to make motion sickness a signficant problem.
This article appears to address none of them, and your comment appears to be premised on the idea that those criticisms hadn't been made.
Oakland has BART access, what other last-mile infrastructure are you referring to?
WRT destructive disruptions, I believe there was a section dealing with sudden tube repressurization. If the failure mode is effective, it seems like an attack would be less destructive than one on a train, due to the smaller pod size.
If CapEx is much lower, and energy cost is lower, the ticket price should be lower, unless the maintenance cost is much higher (it may be due to exotic requirements, but it's not fair to say that what he's describing bears no relation to actual cost structure - it's just not complete).
No idea about the routing/tunneling estimates. Were his per-mile tunnel cost estimates much lower than normal?
The motion sickness complaint seems like it would have legs, since there won't be any view of the horizon - your eyes will be reporting a static environment outside your body, and your inner ear will be doing very much the opposite. Then again, planes experience turbulence and mild G forces and have the same characteristic for most passengers of not seeing the horizon. Maybe motion sickness was a much larger problem in the past, based on the presence of barf bags at every seat.
Musk's plan runs from Hayward to Sylmar. Both are up to 45 minutes from the HSR endpoints in traffic.
Musk's plan specifically calls for TSA-style security.
Your third point is nonresponsive to the argument. The ticket cost will reflect opex, but Musk's plan doesn't include it.
Yes, his per-mile tunnel cost estimates were extremely low.
Airplanes occasionally experience motion-sickness-inducing G's. Hyperloop pods will every trip. You'd at least want to know if the design is a vomit comet before you sank billions into it, would be the right point to make here.
Yeah, I can't see very clearly on the little map posted. Some of the routing diagrams appear to go into SF proper, but the suggested station location appears to be just south of Oakland (tptacek says Hayward). It's on the BART line, but yeah, it's like an hour to SF on the BART, then.
I don't see how poorly chosen station locations invalidates the plan, though - those are just proposals, perhaps because it would be much more involved to estimate land prices within the city. It'll make it much more expensive than the figures they mention, but that doesn't make the overall concept much less interesting, since the land rights will almost certainly still be much cheaper than an on-the-ground solution like the current HSR that we seem to be willing to build.
The costs are based on Hayward to Sylmar. You can draw whichever lines on a map you want, but rights of way into SF proper and downtown LA are intractably expensive. Again, this is an advantage HSR has over "Hyperloops": HSR can reuse preexisting last-mile right of ways, and Hyperloops simply can't.
One critique of Musk's plan pointed out that the Shinkansen trains were essentially a frivolous novelty until they were brought into city centers. The same thing was true of Southwest Airlines trying to service NYC from Idlewild. You have to terminate transit lines at places people want to go.
Also, the bar you're trying to set for critiquing the Hyperloop is too high. An argument against Musk's plan need not show that it's impossible to build. Rather, the bar is simply that an unproven new technology must have significantly better cost and performance characteristics than HSR. Nobody is going to drop many tens of billions of dollars to build this thing "just because".
There are two parts to the Hyperloop "proposal": one is the technology, which is interesting; the other is the route, the cost, the politics. There are critiques of the technology and boosterism of the technology -- I'm not able to judge, and I don't doubt that the idea is cool and possibly a way to build a high speed interconnect from some arbitrary point A to some other arbitrary point B.
But the rest of it, the ridiculous route proposed, the estimates of right-of-ways and construction costs, and the comparison to the CA HSR plans that are going forward -- invited explicitly by Musk -- those parts of the plan are ipso facto nonsensical. That's why some people think it's just a tactical salvo of disinformation aimed at fragmenting what political support CA HSR has.
> I don't see how poorly chosen station locations invalidates the plan though - those are just proposals, perhaps because it would be much more involved to estimate land prices within the city.
They invalidate the plan as an alternative to the HSR plan, which doesn't avoid the issue of connecting places people actually are to places people actually want to get, which is kind of an important part of any mass transit proposal.
Firstly, the article in question is about the technical feasibility of hyperloop, which is in question because it's not something that's ever been done before and it's a non-trivial application of aerodynamics et al. Secondly, if you insist on changing the subject from one of technical feasibility to one of economic feasibility you can't just spew a bunch of opinions without backing any of them up. This article isn't meant to address the economics of hyperloop and implying that it should is unfair.
The entire point of the comment you're talking about was to point out that the nature of the most substantial critiques of the Hyperloop were economic and not (to use your term) "technical". It's your comments that are unfair.
Also, none of these are my opinions; they're opinions distilled from published critiques of Musk's plans. I didn't simply make them up.
It's easy to write off what I've said as overly critical, especially since the underlying sentiment has some valid points. But here being right for the wrong reasons or being close enough is just not acceptable. Precision isn't just important, it's everything. Whether HSR or hyperloop we're talking about a cutting edge multi-billion dollar infrastructure project. Californian highspeed rail is expected to cost more than the Manhattan project (adjusted for inflation). This is not a topic that allows for sloppiness in its discussion.
If a technical article about how facebook is able to scale was posted to HN and then someone made the comment: "Everyone knows that scaling java services is easy, the real problem is that facebook doesn't have a clue how to monetize effectively." people would jump all over them. Regardless of whether or not the criticism of facebook's monetization strategies was accurate. When you make a fundamental technical error on that scale it immediately red flags whatever point you are trying to make, and if the rest of your post is just assertions and opinions with no backup then your post should be ignored, and rightly so.
If you want to talk about multi-billion dollar high technology projects and you don't care about getting the details right then I suggest you go to the bar and discuss things with the other patrons there. If you want to have a serious discussion though then you better come to the table with the correct facts.
None of these seem impossible to overcome. The current proposed HSR is targeted at $60-100 billion, the estimate for Hyperloop was $9 billion. I find it hard to believe that Elon Musk who sent a rocket to an orbiting space station would be off in his calculations by the 550%-1000% needed reach the price of HSR. So I think we should be impressed by the results of this study and get on with more studies to address the additional concerns tptacek posted.
Edit: I'm not trying to rebut or argue about any of the challenges. I'm just saying I find it highly unlikely any of them are 50+ billion dollar problems.
"Because Elon Musk" is not a real rebuttal to any argument.
A somewhat cynical but I think on-the-money assessment of the Hyperloop is that it isn't at all a real proposal, but rather a sleight of hand to reduce buy-in to the CA HSR plan, which Musk opposes. That being the case, investing money in further studies seems like a dumb plan. Extraordinary claims require extraordinary evidence, and there are extraordinary claims in Musk's proposal with no evidence backing them up, so the onus is probably on him.
> it isn't at all a real proposal, but rather a sleight of hand to reduce buy-in to the CA HSR plan, which Musk opposes.
Absolutely. People familiar with the tech industry should recognize this pattern: Announce a vaporware [1] product as part of a FUD [2] campaign against the enemy.
When considered in this way, Musk's actions with Hyperloop make a lot of sense. This is a classic FUD move against CA HSR.
In what way are Musk's criticisms of the CA HSR plan FUD? Frankly, the HSR plan is a dud, and his criticisms are largely, if not entirely, valid. The cost is astronomically high, as a result of that the ticket costs will be greater than airfare. The route they've chosen also means that the journey will take far longer than it should. Would you actually consider taking a 2 hour 38 minute train trip from LA to SF at > $200 round-trip?
Even if Musk's Hyperloop proposal remains only a proposal, if nothing else it should give people serious pause about the existing plan, and hopefully force a revision of it. The route through Palmdale is utterly pointless, tacks on a dozen minutes to a trip that's already too long, and exists largely to satisfy NIMBYs and give fat checks to a bunch of property speculators. That particular element of the HSR plan reeks of cowardice, corruption and graft. Consider this as an alternative:
This is actually one of my biggest disappointments with the Hyperloop announcement. Musk said early on that it wasn't a vacuum tube. But in the end, we have a tube with vacuum pumps, and an air pressure much lower than that of Mars. In my book, that is close enough to a vacuum tube that it sounds like purposeful mis-direction on Musk's part. I.e., when he said (when he first mentioned the idea) that it isn't a vacuum tube, it would have been more honest to say that it isn't a complete hard vacuum tube. Would have cut out on some of the more wild speculations.
"Vacuum tube", aside from being a complete misnomer that's more usually applied to 'pneumatic tube', betrays the concept in one particular area:
It's a battery-powered hovercraft inside of a soft vacuum tube (soft vacuum being within reasonable reach of cheap pumps), with boost segments to get it up to speed.
Usually, vacuum concepts rely purely magnetic levitation & propulsion. The fact that it's an air cushion vehicle in a soft vacuum IS the novel concept here.
I think it would be misleading to call it a vacuum tube, since there are well known implementations of that where the capsule is moved by air pressure/vacuum. Meanwhile the hyperloop has electric propulsion. If he had said vacuum tube, no one would have guessed the propulsion mechanism. The air pressure being reduced in the tube is done more for efficiency than as the mechanism of movement.
While it might seem like a vacume the amount of air left in the tube makes it far cheaper to operate. It's one of those 1 +/- .001 foot rod is not that expencive but a 1 +/- .0001 foot rod is getting there and a 1 +/- .00001 foot rod even more so. Basicly vacume pumps cost more, use more energy, become more delicate, and move less air the closer you get to hard vacume.
However, there is still plenty of air in the tube to be an issue at the proposed speeds thus making Hyperloop cheaper and more complex than a traditional vacume transport.
But isn't the fact that it is not a vacuum an important aspect of the design? First, some air is used to elevate the train. Second, it's easier to maintain a near vacuum than a total vacuum.
As a planner, my biggest questions are around land acquisition. It's not usually the kit that's the super expensive part of these projects. That said, I suppose it's possible that the land requirements for the hyperloop are less.
I meet a lot of curmudgeonly planners who like to downplay the potential impacts of new technology (hyperloop, self-driving cars, etc.), but I'm open to the possibility of truly disruptive tech. Still, I have a hard time imagining that the land acquisitions will be that much cheaper for hyperloop.
A large point of the proposal was the massively reduced land use requirements coming from using a structure on pylons, and from having most of it follow the existing highway on land that's already publicly owned.
The assumptions regarding land use were pretty well covered in the PDF Elon Musk released.
My friends in aerospace always say that there are two kinds of folks who believe simulations: Those who write the software and those who have to use it to justify their existence. Everyone else knows there's can be huge gaps between simulation and reality. Granted, things improve over the years but c'mon, who are they kidding.
> “I don’t immediately see any red flags,”
Says the simulation guy.
Really?
> “I think it is quite viable.”
Says the simulation guy. Again.
Hmmm. I'm not building rockets or cars but, you know what, I'll bet you --simulation guy-- a good dinner this thing is as viable as trying to evolve a flying elephant in a lab. You might theoretically be able to get there with enough time, but in practical terms it is impossible.
For starters I want someone to explain how we are going to build massive columns along the middle of Interstate 5 every 100 meters for four hundred miles.
And then tell me how we are going to do that and put a four hundred mile tube on top of it (let's ignore impossible construction details) for six billion dollars when building an incredibly short (by comparison) bridge in San Francisco cost the same?
Simulations like this one are like special effects in movies. They look great and make you feel like we are living in the future but they are far --very far-- from being realized. Look at something like C3PO. Thirty six years have passed and we are nowhere near such a robot being realized.
I am not an engineer outside of IT, but what if you submerged the hyperloop in the pacific between SF and LA? Would thermal expansion no longer be an issue because you're using the ocean as a thermal sink? And you can provide enough positive air pressure to keep water out of your loop.
Right, but what if its not feasible on land due to thermal expansion, but is feasible underwater with slightly higher power requirements to overcome air resistance? Just a thought.
The design is intended to be robust with regard to leaks (pumps can overcome some leakage to keep interior at a near-vacuum). This would not work underwater.
Pumps can overcome a small amount of leakage - from tiny cracks between bolt threads, etc - places that an un-reactive gas can make it through a huge pressure differential. In shallow water, one has the viscosity of water to work with, which makes this much easier in liquid phase.
What I don't know is how pumps, and cracks, would react to gaseous H2O versus gaseous N2; Or if perhaps a liquid with low offgassing potential could be used as a boundary layer to seal cracks instead of water (which, while much higher viscosity than a gas, remains lower than most liquids).
One big advantage of any submersed liquid approach: Earthquake resistance.
Additional notes:
My main theory before the announcement was that the concept used a fast-speed-of-sound, low-density STP hydrogen tube and maglev rather than slow-speed-of-sound air tube, or an expensive-to-seal vacuum tube. An STP hydrogen tube hovercraft levitation model still seems pretty damn attractive to me, especially with a sealing liquid buffer of some sort - it cancels out the problem of water-vacuum interface, and in water, flammable seals, as well.
My understanding is that the thermal expansion is taken care of near the stations with a telescoping section. So the tube then has to be free floating, i.e. not attached to the pylons.
No, it specifically addresses that. The white paper says that rather than rigidly fixing the tube to each pylon, it would be fixed to a damper that would "absorb the small length changes between pylons." The problem with the white paper's approach, as the blog post explains, is that the length changes are far from small.
I wonder if they could use carbon fiber?
It has near zero thermal expansion.
I have this awesome vision of some big machine sitting at both ends where they knit fibres together, cure it then just basically extrude the thing the whole way and meet in the middle.
Yes it's expensive but with the magic of science and a bit of hand waving surely our processes have advanced to the point where this is becoming feasible?
Unfortunately I have no idea if a carbon fibre tube is suitable to operating at sub atmospheric pressures...
Yeah, this seemed like the biggest killer, besides inertia and politics.
My friends and I were wondering aloud if you could put a slight bow in the pipe - so instead of expanding lengthwise, the pipe might raise and lower at certain places. Of course, none of us are engineers in that sense.
1. Most of the tubes would need some bowing anyway for curves, since they can't find a perfect straight path from LA to SF
2. Tests show that tubes where L >> D, thermal expansion is linear along the length. If you restrained both ends you'd get the buckling in the interior sections that you describe. That might even be a bigger problem though because it would affect the path geometry and alter the attitude control requirements of the pods. I think the wrinkling in the tube skin would also be more dangerous than just letting it stretch.
The Ansys simulation showed very uneven stress markings alongside the body of the pod. “We see a lot of shear stress areas,” Sovani says.
They didn't study it but I wonder what the stress on the curved portions of the tube wall would be? If the vehicle is prone to shear failures, I would imagine the tube would be as well.
I'm still hung up on what happens if there's an emergency on board? Yes, bathroom related would be one, but what about something like a heart attack? Are there any other forms of mass transit that don't allow for an emergency stop or at least the possibility of gaining reasonable assistance from another person on board? I guess the closest comparison would be an intercontinental plane, but planes have space to move around and bathrooms.
Well, with an average of 15 minutes until you arrive at the other end, where presumably EMTs are already waiting, I don' think you really need a close comparison. 15 minute response times are hardly unheard of and you can put yourself in a much more isolated situation just driving down the road in a car in some of the less dense parts of America.
I don't think this is a problem that actually needs a solution (though the public may very well demand one irrationally, much like the safety concerns the public is going to have with self-driving cars that are safer than human drivers...).
I agree, I don't see the damage.
In most real life situations anything that doesn't kill you immediately can wait 15-20 minutes, and when you get out the other end you can have great medical treatment.
Anything that requires you to be seen by some serious medical support faster than that will generally kill you regardless of the situation (ie. Left Main coronary embolism which kills 250,000 Americans a year)
Edit: complete misuse of iatrogenic. Too little sleep. Whoops
>I'm still hung up on what happens if there's an emergency on board? Yes, bathroom related would be one, but what about something like a heart attack? Are there any other forms of mass transit that don't allow for an emergency stop or at least the possibility of gaining reasonable assistance from another person on board?
Well, how it's different from a regular high speed train? (Besides reaching it's destination much much faster?) Where would a regular high speed train do an emegergency stop?
Other methods could be even worse, despite far more popular. A taxi in a traffic jam for one. You'd probably need more than 15 minutes to get to a hospital.
This is idea of "it's an emergency, we must stop the train" is often completely flawed. Lets say you trigger an emergency stop. Now what?
In all likelihood you are going to be further from a hospital or any qualified assistance than you would if you let the train continue at full speed. If you're really unlucky, you're in the middle of nowhere.
I really hope this project gets off the ground. I don't know if it will prove financially viable in the end. Maybe the most it will accomplish is serve as an experiment to tease out aspects of high speed transportation that would work from those that don't.
Progress is made by pushing the envelope of what's feasible. The biggest shame of all would be to become a society that is so afraid of making mistakes that we can't move forward.
Technically viable possibly, and about as economically viable as all other rail solutions offered so far in the US. Speed isn't the issue with rail, its point A and point B, well that isn't really fair. The number one obstacle to rail has always been politicians who take any well conceived route and demand it go to their hometown.
Having Symmetry and exact shape is more of an optimization issue. Ansys numerical simulation tools are not really needed for feasibility check. Hand calculations are sufficient, mostly taken care of in the alpha design document. However, the issue of having sufficient space to store steam is somewhat unclear and needs some brainstorming..
How many large scale infrastructure projects has this software company executed and delivered? Oh, they just supply software to people that do do that? Ok.
(S)he didn't say it was. (S)he said "near vacuum." And that comes straight from the hyperloop paper:
"Just as aircraft climb to high altitudes to travel through less dense air, Hyperloop encloses the capsules in a reduced pressure tube. The pressure of air in Hyperloop is about 1/6 the pressure of the atmosphere on Mars. This is an operating pressure of 100 Pascals, which reduces the drag force of the air by 1,000 times relative to sea level conditions and would be equivalent to flying above 150,000 feet altitude."
There's no such thing as a "full vacuum". 100 Pascals is 0.1% of atmospheric pressure at sea level. It's pretty frickin' close to a "full vacuum". If there's a leak anywhere in the tube you're boned.
By full vacuum I was referring to the conditions you have in space. And no - when you have even a slight allowance for a margin of 'error' or leakage - that's all you need to balance things out. And if the leakage is higher, it's a matter of efficiencies reducing - not complete failure.
1-3 are already figured out, they are not hard problems or very different than the existing proposed HSR line. 4 is addressed and the only part that you can't really know until you dive into actual implementation. It is estimated though.
I take it you mean to imply that by "figured out" I mean we have a working example. Obviously not, or we wouldn't be lacking a hyperloop. By figured out I mean all the requisite problems have been solved. It isn't a mystery how we could build a tube and put vacuum pumps on it. And we've built plenty of complex structures in seismic areas.
This is not reddit, and it seems to be a problem with engineers of a certain age, but no one wants to constantly hear your 20 year old cartoon references throughout the day. Also I am incredibly glad that the most prominent south asian on network TV isn't a white dude's impression of a stereotypical immigrant.
#2: "Yeah, we could simulate it and talk about the results in technical sounding but vague terms that we can't be meaningfully challenged on. But what do think will get more publicity, saying it will work or that it won't? There's plenty of latitude in the specs for us to end up with either."
#1: "That it will, of course. We want our customers to think they'll be validated by our software, not shot down. But make sure you provide a little advice so it's clear that we add value. And also hedge a bit so that just in case Hyperloop is a technical disaster, we don't look terrible."
#2: "Sounds good. I'll call Bloomberg and see if they have any spots available for vacuous puff pieces."
#1: "Was that a vacuum joke?"