Elon Musk Begins Digging a Hyperloop Tunnel In Maryland (baltimoresun.com) 146
Elon Musk has been granted permission by Maryland to start digging tunnels for his hyperoop transit system that he wants to build between New York and Washington. "Hogan administration officials said Thursday the state has issued a conditional utility permit to let Musk's tunneling firm, The Boring Co., dig a 10.3-mile tunnel beneath the state-owned portion of the Baltimore-Washington Parkway, between the Baltimore city line and Maryland 175 in Hanover," reports Baltimore Sun. From the report: It would be the first portion of the underground system that Musk says could eventually ferry passengers from Washington to New York, with stops in Baltimore and Philadelphia, in just 29 minutes. Maryland's approval is the first step of many needed to complete the multibillion-dollar project. Gov. Larry Hogan toured a site in Hanover that aides said could become an entry point for the hyperloop. The state does not plan to contribute to the cost of the project, aides said. Administration officials said they will treat the hyperloop like a utility, and permitted it in the same way the state allows electric companies to burrow beneath public rights-of-way. It was not immediately clear Thursday what environmental review or other permitting procedures must be completed before the company breaks ground.
Heigh-Ho (Score:2)
Dig or not Dig? (Score:5, Informative)
Title says "Begins Digging" yet he's only now been "granted permission"?
Wrong headline is wrong.
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Title says "Begins Digging" yet he's only now been "granted permission"? Wrong headline is wrong.
They can't even start yet, the permit is conditional and they've still got to meet the conditions. But when it comes to Musk hype on /. all is fair.
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Elon is the new Steve.
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Haha! :)
Is Elon Musk doing it personally with a shovel? (Score:2, Interesting)
More likely someone else is doing the actual digging and planning
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Although it's not informative, that's exactly how I envisioned this, with Elon mopping his pasty head with a red bandanna handkerchief and waving off executive assistants with beeping phones. "Tell Space X to call back later, I need to knock out another 10 feet!"
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I know you're joking but there's something about his personality that just rings true. A relentless, scrappy bastard that would pick up a shovel and start digging if he ran out of money, and that would probably call people that were around during the sunny days and shame them into getting down there to help.
The kind of thing that I could picture Jeff Bezos, Michael Dell or Bill Gates do in their days. All those guys are/were the real deal. This is the kind of leadership that's sorely missing in tech, tough
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With you until you said "Gates".
read on (Score:2)
Maybe you don't know him that well. I suggest to read this story from joelonsoftware:
Then I sat down to write the Excel Basic spec, a huge document that grew to hundreds of pages. I think it was 500 pages by the time it was done.
[...]
In those days we used to have these things called BillG reviews. Basically every major important feature got reviewed by Bill Gates. I was told to send a copy of my spec to his office in preparation for the review. It was basically one ream of laser-printed paper. I rushed to get the spec printed and sent it over to his office.
[...]
I noticed that there were comments in the margins of my spec. He had read the first page!
He had read the first page of my spec and written little notes in the margin!
Considering that we only got him the spec about 24 hours earlier, he must have read it the night before.
He was asking questions. I was answering them. They were pretty easy, but I can’t for the life of me remember what they were, because I couldn’t stop noticing that he was flipping through the spec
He was flipping through the spec! [Calm down, what are you a little girl?]
and THERE WERE NOTES IN ALL THE MARGINS. ON EVERY PAGE OF THE SPEC. HE HAD READ THE WHOLE GODDAMNED THING AND WRITTEN NOTES IN THE MARGINS.
He Read The Whole Thing!
https://www.joelonsoftware.com... [joelonsoftware.com]
Bill Gates was the real thing.
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More likely someone else is doing the actual digging and planning
To handle the physical tunnel work, Musk has recently recruited John Henry, who is one of the top rock stars in the field.
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Elon's got you covered.
The Boring Company [wikipedia.org]
Abandoned Tunnels (Score:1)
Abandoned tunnels are a good place to grow mushrooms. I imagine the chefs in higher-end resturants in the DC area will be enthusiastic about this news in a decade or so.
Re:Abandoned Tunnels (Score:5, Insightful)
It's fun and rewarding to be a bird of ill omen, no? Sit there like a know-it-all and piss on people who are trying to make things happen?
Not so long ago "electric car" meant a shitty golf cart that reached maybe 15mph. Now we have access to electric cars that do the driving for you and can do 0-60mph in 3 sec. Also not so long ago, sending shit to space was obscenely expensive and was mostly a one-way trip for the rocket; now there's reusable rockets and the cost of sending shit to space is 4x lower than what the NASA or Air Force used to pay.
What the fuck more do you need to be amazed by that guy.
Tunnel (Score:2)
That's interesting, because it would seem to mitigate one of the problems with the hyperloop concept. Namely, if the tunnel ruptures, there's a fast-moving wall of air rushing at anyone inside the tunnel.
http://dailycaller.com/2016/07... [dailycaller.com]
If the tube is in a tunnel, there would be much less air available to create such a pressure wave. Or if it's bored through rock there would be almost no air at all inside the tunnel but outside the tube. I think this would mean there would be, at worst, a much less sever
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Anyone who thinks you'd be hit by a crushing "wall of air" needs to read up on shock tube experiments, and in particular how propagating shocks respond to high aspect ratios (length relative to aperture size)
When the shock hits you, is it moving fast? Yes. Several times the speed of sound.
When the shock hits you, does it have meaningful density? No, unless you're talking a huge rupture and you just happen to be right next to it at the time.
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Well, I don't think it would be acceptable to say that the passengers will be fine unless there's a huge rupture and they're right next to it, in which case everyone could be killed. And even if that were not a concern, putting it underground seems to solve a bunch of other problems too.
Re:Tunnel (Score:4, Insightful)
Well, I don't think it would be acceptable to say that the passengers will be fine unless there's a huge rupture and they're right next to it, in which case everyone could be killed.
Making a huge rupture in a 1" thick steel tube will require a large quantity of explosives. Such a quantity of explosives won't harm a bus full of passengers unless they're right next to it, in which case everyone could be killed. We don't take that as an argument for eliminating buses.
putting it underground seems to solve a bunch of other problems too.
At the expense of creating a bunch of other ones. Engineering is all about tradeoffs. Boring will make sense primarily in densely-populated areas. Elsewhere, the original elevated tube design will be better, I think.
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Making a huge rupture in a 1" thick steel tube will require a large quantity of explosives. Such a quantity of explosives won't harm a bus full of passengers unless they're right next to it, in which case everyone could be killed. We don't take that as an argument for eliminating buses.
What makes you think it will be a 2.54cm (1") thick steel pipe. Have you any idea the tech and subsequent cost that would go into making that type of pipe? Not only that but you have to join the pipes with "O" rings (it is a vacuum tube after all) and you also have to take into account the thermal expansion coefficient of steel.
Remember that what has been proposed is a very long vacuum tube so there would be normal air pressure outside so even with a slight deformation you are going to have a rupture whic
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What makes you think it will be a 2.54cm (1") thick steel pipe. Have you any idea the tech and subsequent cost that would go into making that type of pipe?
Unlike you, apparently, some people have read at least the original concept document. To quote:
"A tube wall thickness between 0.8 and 0.9 in. (20 to 23 mm) is necessary to provide sufficient strength for the load cases considered such as pressure differential, bending and buckling between pillars, loading due to the capsule weight and acceleration, as well as seismic considerations"
Strangely enough I'm also pretty sure that the guy whose company builds large tubes that they then launch into space has a pret
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Well, he's still as annoyingly smug as when he first started laughing at the idea. I find it slightly amusing that he's seemingly unaware of the irony of pooh-poohing the idea of hyperloop while mocking the Kitty Hawk comparison.
There is a huge difference between heavier than air flight by the Wright Brothers and the so-called Hyperloop proposal. For starter people like Leonardo da Vinci (1452 to 1519) knew about flight structures well before the first powered flight. From then on aircraft developed quickly and surprisingly the Wright Brothers never got any patent money from it.
When discussing a vacuum container at sea level the pressure on the container will be one atmosphere which is 101kPa or 15psi and not equivalent to 10 met
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For starter people like Leonardo da Vinci (1452 to 1519) knew about flight structures well before the first powered flight. From then on aircraft developed quickly...
I'm not sure I see the point you're trying to make here. As many people are keen to point out the notions of vacuum tubes, magnetic levitation, air bearings and indeed pretty much every engineering concept used in the hyperloop proposal are not new either.
When discussing a vacuum container at sea level the pressure on the container will be one atmosphere which is 101kPa or 15psi and not equivalent to 10 meters of water.
Are you sure [calctool.org] about that? I'll repeat my original assertion in case you misread it: "The pressure differential between the atmosphere and an evacuated tube is roughly equivalent to a tube at atmospheric pressure submerged in 10 metres of water"
...what has been proposed is a vacuum tube that is well over 100km long...
The original
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I wouldn't usually reply to myself, but I rather felt the need to make a correction...
Does a 3 foot length of evacuated tube share the same characteristics when repressurising as a 300 foot length of tube? A 3000 foot length? Not exactly. Once you get beyond about 33 feet (essentially the pressure difference between a vacuum and 1 atmosphere) things change
I'm not entirely sure what I was thinking (other than "finish typing, it's nearly beer o'clock") but I clearly had a massive brain fart here. This '33 feet' figure is complete bollocks, in relation to what I was talking about, primarily 'cos we're talking about horizontal tubes, not vertical, and also 'cos air ain't water.
No excuse really. Mea culpa!
The actual figure is more likely to be in the region of tens of kilometres
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When discussing a vacuum container at sea level the pressure on the container will be one atmosphere which is 101kPa or 15psi and not equivalent to 10 meters of water.
The pressure differential between a container of perfect vacuum and ambient atmosphere at sea level is about 14.7 psi. The pressure differential between a container of air at one atmosphere and ambient seawater at 10m depth is about 14.7 psi. Each 10m of seawater depth increases ambient pressure by approximately one atmosphere. At 100m, pressure is 10 atmospheres higher than the surface. Freshwater is less dense than seawater, so pressure increases a bit more slowly.
Any SCUBA diver knows this.
Here's a c [calctool.org]
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Remember that what has been proposed is a very long vacuum tube so there would be normal air pressure outside so even with a slight deformation you are going to have a rupture which would send out a shockwave traveling at the speed of sound and anything in the tube would be pulverized.
Ignoring the rest of your nonsense because there's only so much time in the world...but this one is just too easy because you're simply too ignorant or too stupid to understand how pressure works.
The difference in pressure between two areas along whatever separates them exerts the pressure on that isolating material. Given the lowest pressure you can have is zero (total vacuum) and standard pressure at sea level is 1ATM or ~15 PSI...the largest pressure possible against the hyperloop tube is a measly 15PSI
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Re: Tunnel (Score:2)
Tunnels are mich mire expensive than surface tubes. When they rupture, you get a mud slide and surface structures can be affected. See Rastatt tunnel accident in Germany. They drilled a close to surface tunnel. One of the wall segments collapsed with devastating effects.
Vibration? (Score:1)
I remember visiting Shanghai last year where they have a maglev that speeds you from the airport to just outside the city. I was told that a residential area was built along it but that the maglev generated a huge amount of vibration that affected people's health so they moved away. I don't know if this is apocryphal, but do wonder how much vibration the design will generate and how that would impact the environment, people living above it, cars driving on icy roads above it, etc.
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After the Channel Tunnel was built the train line was extended, in stages, all the way into central London. Large parts of this track run variously on viaducts over rivers, roads and other rail lines and in tunnels under roads, buildings, and other rail lines. The trains that run on these tracks weigh 700 tonnes and travel up to 300 km/h (albeit they do slow down in some sections).
These trains have been running for closing 15 years now, and, as far as I know, no building has yet collapsed because of them, n
But can it make a profit (Score:2, Interesting)
While there is existing technology, the mag lift, in use, that can move two hundred plus people at a time on a monorail (cheaper then a tunnel) at speeds up to 400 km per hour.
The future of transportation is moving a large
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People made all the same criticisms about air travel back in the 1920's. Their mistake was assuming that the technology would never develop much further than the (slow, cloth-and-wood framed, 1-2 person) aircraft that were in existence at the time.
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People made all the same criticisms about air travel back in the 1920's. Their mistake was assuming that the technology would never develop much further than the (slow, cloth-and-wood framed, 1-2 person) aircraft that were in existence at the time.
You could build and fly bigger aircraft without changing the infrastructure. Not so with Hyperloop. Try a different analogy.
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You could build and fly bigger aircraft without changing the infrastructure.
Untrue -- bigger planes required bigger runways and bigger terminals. And so, bigger runways and bigger terminals were duly built.
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You can grow airport runways and terminal buildings progressively and relatively easily (as you can railway stations - the equivalent) - just buy some more land. Upgrading thousands of miles of railway lines however, including enlarging tunnels and strengthening bridges, is a task of a higher order.
UK railways suffer to this day with having been built too small. Upgrading Hyperloop to take larger vehicles would mean scrapping the entire tube and starting again. Fortunately I don't think that Hyperloop will
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I've never liked this argument, as it's based on what we know is a successful technology: Flying.
You could just as easily say "This hyperloop is getting the some condemnation that Phrenology once received!"
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I read that government is not involved.
Capacity is actually a loading problem (Score:2)
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Musk has never been concerned with making a profit with any of his companies. Both Tesla and SolarCity have never been profitable. For the last 5 years he has been saying Tesla would begin turning a profit the following year. SpaceX is barely profitable because they severely undercut the competition to get launches. Not even PayPal was profitable when it was acquired by EBay.
Same thing happened with Amazon. No profit for 12 years, and now they're printing money and are slowly driving the competition out of business. Who's going to disrupt Amazon now?
Re: But can it make a profit (Score:2)
To rephrase that, SpaceX charges far less than the competition while still turning a profit.
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A Terrorist's Wet Dream (Score:2)
which will necessitate airport levels of security.
29 minutes huh? So does that mean passengers get 10 minutes to board/deboard this thing????? It's gonna have to be quickly loaded. Leaving 9 minutes of travel time?
What if a hyperpod can't leave on time? Are the margins of error such that it can be squeezed in prior to the next hyperpod? Or will that hyperpod need to be retired and the passengers put on another hyperpod. What does that do to scheduling passengers?
And how are passengers going to react
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What you're saying is that you're not smart enough to recognize what you don't know.
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29 minutes huh? So does that mean passengers get 10 minutes to board/deboard this thing????? It's gonna have to be quickly loaded. Leaving 9 minutes of travel time?
The pods are small. Think subway car-sized, not jumbo jet sized. How long does the subway stop at each location? Two minutes? Pods are expected to have a maximum speed of 760 mph, which would cover 226 miles in 18 minutes.
And how are passengers going to react to the acceleration/deceleration necessary
Well, at 1/4 gee acceleration (8 f/s^2), you'd need 139 seconds to accelerate to 760 mph. For the described journey, you'd have to accelerate or decelerate 6 times, so that would take 14 minutes, leaving 11 minutes at top speed. During each acceleration or deceleration, you'd cover 14.7 mi
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LOL you Elon shills are so funny.
I accept your concession.
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What if a hyperpod can't leave on time? Are the margins of error such that it can be squeezed in prior to the next hyperpod?
There's multiple train stations in India that handle 500,000 to 1,000,000 daily passengers, and their railway infrastructure runs on switches and relays that were obsolete before man set foot on the moon. There's not a lot of room for errors there and yet they manage.
So I think it's fair to say that Elon Musk, his unlimited Mastercard and his legion of PhDs can figure out how to handle delays in a transportation system designed for thousands of passengers a day.
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which will necessitate airport levels of security.
So you won't be allowed on board with a pocket knife in case you demand the computer divert the pod down a different tube, but you'll be allowed on with 2 kilo of lipo batteries?
Even so I don't see why. We've had these things called "trains" for years which seem to work just fine.
29 minutes huh? So does that mean passengers get 10 minutes to board/deboard this thing????? It's gonna have to be quickly loaded. Leaving 9 minutes of travel time?
Um what? Have you
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The 29 minutes is the travel time, not the loading time. The loading time is to walk in and sit down. Baggage car might come after one for passengers, its not required to carry both in the same vehicle. Baggage transfer would probably be highly automated and therefore very fast.
I believe that these are tubes between 2 points, and each "point" requires getting up and changing vehicles, like hub airports. Vehicles leave whenever they are ready to leave. There should be no interleaving of vehicles runn
Not likely (Score:4, Interesting)
10 miles? (Score:2)
10 miles is a stunt. It would take most of this distance to accelerate and decelerate to the touted speeds. Lots of people are going to lose lots of money on this stupidity.
Wow this seems Amazingly Fast!! (Score:2)
Or is the fact that (WunderKind) Elon Musk owns the company doing this, means that nothing harmful or bad could ever come out of this.
Just to make it clear I am not against this, it just seems to be moving amazingly fast
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I'm pretty sure this is a state that allows fracking. The bar for approving underground stuff is low.
If he just takes it down to a depth that is extremely unlikely to hit anything ever put in from the surface or disturb any surface waters (necessary to avoid pumping like crazy anyway), there is little environmental impact that anyone cares about other than disposing of the removed material which should be very non-hazardous and possibly in demand for fill.
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If he just takes it down to a depth that is extremely unlikely to hit anything ever put in from the surface or disturb any surface waters (necessary to avoid pumping like crazy anyway), there is little environmental impact that anyone cares about
This sounds like the premise of another high quality syfy movie
Hype - PR - loop (Score:1)
Tinfoil hat time... (Score:2)
Just a bit of paranoid speculation that perhaps all this hyper-loop stuff is essentially a money laundering scheme for the government to subsidize and fund Musk's other projects (Rockets, Cars, Batteries) without seemingly doing it directly which might have political ramifications. This type of project is the kind of thing easily in the many many billions, and will take decades to complete, both of which could be inflated at cost and length of time, essentially providing Musks ventures (which haven't or won
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The Outlaw, Josey Wales.
Good film!
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What subsidies do you envision existing for tunnel boring?
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You are like the cool-aid jug crashing though the wall whenever Elon's name is mentioned.
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The tech isn't practical, nor will it be preferred to air travel if similarly delayed by security. However the "abandoned tunnels" will become brand new state of the art bunkers for the military.
How can Musk get so much government subsidies? This is how.
But the tech is practical if you have the mind of a troglodyte. What are they teaching people in the schools nowadays can't people detect the Snake Oil?
Re:Boring (Score:5, Informative)
So many people making the same joke.
Okay, let's try to add something to the conversation. Here's what we know about the ideas behind Boring Company so far. First, the tangential aspect: the non-Hyperloop car sleds. Tunnel costs are almost linearly proportional to cross section. By having cars on sleds you don't need any lane margin around the vehicles and can use a much smaller (and thus cheaper) tunnel. Also by moving them at very high speeds you have a much higher throughput, and by computer control, you can space them closely (getting even higher throughput).
However, as for the boring itself: the rate at which a TBM bores is proportional to how fast the head is rotated. In hard rock boring they generally also spend a large portion of the time stopped; a new casing segment is set up to both support the walls and for the TBM to push off of. During downtime, maintenance tasks such as replacing cutting disks are conducted.
When you read through literature on the topic, you find that the answer to "how fast can you X?" or "Is it possible to Y" are frequently "We don't know - contractors are payed to complete a given task and generally have little incentive to experiment with new approaches." Boring company seeks to focus on all of them at once. First off, the cutting disks: if the TBM rotates too quickly, the disks heat too much and their (already short) lifetime is greatly reduced. Boring Company is looking to do three things: one, use more advanced alloys (cost more to replace, but nothing compared to the cost savings of faster boring); two, use active cooling on the cutting disks; and three, have them hot swappable so the TBM doesn't have to be stopped. All of these things together in theory should allow the TBM to be run many times faster (so long as everything else associated with the excavation is also correspondingly sped up). It's also being modified to not need to stop for casing; downtimes are only to be for when something is physically broken or there are issues with the geology that need to be dealt with.
Many of the complicating issues with boring, such as unpredictable geology, unmapped buried hardware in urban areas, etc, Boring Company's approach will not eliminate. But the goal (whether they can reach it or not) is to ensure that when they are boring, they're doing so very quickly.
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Wow so much hype with this project.
Okay, I am an Electrical Engineer with well over 35 years experience so what would I know when there is so much pseudo-science associated with the Hyperloop project. No country and I repeat no country has ever built a vacuum tube that even comes close to the length and diameter that is proposed for the Hyperloop when all you need is one rupture in the tube and you have human jelly jam. Snake Oil sale at it's best especially when you consider that the "laughable" Hyperloo
Re:Boring (Score:5, Interesting)
Rocket scientists (way above your level of expertise) used to say landing rockets vertically and reusing them afterwards was never going to work, for all sorts of reasons that an idiot like Musk obviously wouldn't know about. And landing them on barges in the ocean, come on, you've got to be kidding, that's totally ridiculous, nobody would even think of attempting that. Elon Musk is a fool. (That last phrase is a literal quote from a conversation I personally had with an ESA rocket scientist).
Also, making an electric car that people actually want to buy? Just a few years ago almost all engineers in the automobile industry (including, and especially those with well over 35 years of experience) would have told you that was impossible too. Let alone cars that would outperform the fastest supercars while having 5 seats and plenty of room for luggage. You've got to be kidding, that's a totally impossible thing to even attempt. Elon Musk is a fool, it will never work, nobody will ever buy them.
And setting up huge battery installations to make reusable energy viable for countries that were historically suffering from frequent outages? That will never work either, for all sorts of reasons that an idiot like Musk wouldn't know about. Any electrical engineer with well over 35 years of experience can tell you that, but never mind them.
Meanwhile, Elon Musk, effectively not minding those "experts", and unhindered by any "knowledge" on any of these subjects, is on track for a 50% market share in rocket launches in 2018, with more and more of those using actual reused boosters. The last 18 landings were all successful, including some very high energy ones. His Tesla Model S and X are a huge success, and model 3 has almost 500,000 preorders (yes, I know it's delayed a bit on its agressive rollout schedule, but not nearly as much as previous models, months rather than years). O, and that solar battery installation in South Australia seems to be coming together just fine, with another huge installation in Puerto Rico on the way.
Maybe it's time for some of these dinosaurs with well over 35 years of experience to retire if all they can do is say "ok, maybe you got lucky on that first thing we said couldn't be done, but you definitely cannot do this other thing... ok, maybe you got lucky there too, but this third thing, that's definitely impossible... o, wait...". Seriously, you lost all credibility.
Re: Boring (Score:4, Insightful)
No rocket scientist said that. As they did it in the past, such statement would be redicilous. Have a look at the moon landing. However, the landing approach was considered economically not feasible, as you cannot use alle the fuel for lift and you have to carry the landing fuel up and down again.
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C'mon, the "landing fuel" is miniscule since the great mass of the rocket at launch is the "lift fuel" which is gone after the rocket does its primary function. The thing that lands is a hollow, comparatively lightweight tube requiring a slight amount of fuel to accomplish the landing.
Re: Boring (Score:3)
You still have to lift it, which reduces the total mass to orbit. The key question is: Is the reduction in lift off mass less costly and a reusable rocket less expensive than a single use rocket?
Anyway, ESA experiments with a reusable engine (without the tank), as this is the mist costly part of all.
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Is the reduction in lift off mass less costly and a reusable rocket less expensive than a single use rocket?
Considering the refueling costs are a couple hundred grand plus a minor refurb/recert cost vs. $60ish million for a whole rocket I'd say yes. There have been a few instances where they needed the max payload and the rocket had to be expended. The Falcon heavy solves that problem (well, up to it's max launch payload of course).
The tank (and related systems) are not trivial cost either...plus you have to either hard-land that engine or bring fuel along to soft-land it anyhow. That sounds like a solution looking for a problem.
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C'mon, the "landing fuel" is miniscule since the great mass of the rocket at launch is the "lift fuel" which is gone after the rocket does its primary function. The thing that lands is a hollow, comparatively lightweight tube requiring a slight amount of fuel to accomplish the landing.
Really. Have you done the calculations?
Here is a fairly simple calculation to reach the international space station which is 408 km above the earth. Plugin the number 408 into the Orbit of a satellite Calculator [casio.com] and you will get an Orbital radius of 6,786.14 km, a Flight velocity of 7.66 km/s and an Orbital period 01:32 (Yes I have rounded the numbers).
Now consider you have to get your rocket from an orbital velocity of approximately 7.66 km/s through the Earth's atmosphere which will heat any expose
Re: Boring (Score:4, Informative)
First wrong assumption is that the 1st stage, which is what we're recovering, achieves orbital velocity. It doesn't. You now have to completely redo your numbers.
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Following the Tsiolkovsky equation [wikipedia.org], rockets do most of their acceleration when they are almost empty, see this graphics for the Saturn V [braeunig.us]. NASA actually had to turn off one of the Saturn V engine towards the end of the first stage burn otherwise acceleration would have been too great for the astronauts. So the last few minutes of the burn are important.
Basically the Musk approach is that you have to lift some of the fuel, which is not used for lifting but for landing. It may be more costly than it looks. Sci
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Do you have any Engineering proof that Elon Musk's proposed Hyperloop is feasible? There seems to be a lot of hype and little real Science and Engineering. You know the disciplines that get things done in reality.
I have not looked at the proposed solar battery installation in South Australia but since I am well aware of power systems design and of Elon Musk's hype I think it will most likely be a lemon although I am open to changing my mind. Basically, the SA Government screwed up big time and I am thankf
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The biggest thing most people complain about with the feasibility of Hyperloop is the vacuum seal. Musk has stated that in order to seal against the water table you have to have something good up to about 5-6 atmospheres. To go to vacuum or near vacuum you only need 1 atmosphere, so if they can seal to the water table, then they can seal to vacuum.
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Not so much the seal, the cost of actually pumping that air out of a huge, long tunnel.
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And have you actually calculated the energy cost for doing so?
Considering (major maintenance aside) it's a one-time effort with minor maintenance to cover the inevitable minor leaks which is technically reversible if you chose....I pulled up some basic info which says it which 'costs' about 100kJ to empty 1 m^3 at sea level. (plus inefficiencies of your pumping system)
Let's take a 5m diameter, 100km tunnel...about 8x10^6 m^3 so 800GJ or 222MWh
The energy needed is large, but not unreasonable.
Historical electric cars (Score:2)
Also, making an electric car that people actually want to buy? Just a few years ago almost all engineers in the automobile industry (including, and especially those with well over 35 years of experience) would have told you that was impossible too.
And those engineers would have been fools themselves for completely ignoring all the other companie who have been successful at building electric vehicles, some of them for 35 years or more too.
(Random example : Citroen has been making electric trucks and minivan used by the french postal service - the extremely frequent strart/stops and the rather short distances make EV way better than ICE. Even on the only NiCd battery tech available back then)
(Other random example : a few swiss mountain touristic region
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Rocket scientists (way above your level of expertise) used to say landing rockets vertically and reusing them afterwards was never going to work
Leading up to the first time it was done(by Blue Origin), it wasn't that people in the industry didn't think it was possible. It was that there was doubt it would meaningfully reduce the cost of launches. Which is still an open question.
and model 3 has almost 500,000 preorders
Given how loose(that's being kind) Musk is with his numbers and how off he has been with his projections(his Model 3 delivery numbers were off by a whopping 83%!), I take the line reservation numbers with a huge grain of salt. And that's what they are, a $1000 refundable dep
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Tesla is circling the train? Oh...yeah...ok. Let me buy that tesla stock from you then since it's practically worthless anyhow. Take $10 a share?
Your doom and gloom doesn't match the reality that's actually happening.
SpaceX is the only entity launching and landing cargo rockets. BO is great and all, but their rocket was/is a little toy in comparison and does not put any meaningful payload into orbit. As for the cost savings - this has been demonstrated. Not sure what planet you're on but a couple hund
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Tesla is circling the train? Oh...yeah...ok. Let me buy that tesla stock from you then since it's practically worthless anyhow. Take $10 a share?
The only argument I hear to Tesla being successful is its stock price. People said that about Enron, Valeant Pharmaceuticals, and many dot.com stocks back in 2000.
Model 3 shipment numbers are about one month behind targets.
http://www.businessinsider.com... [businessinsider.com] "The company plans to produce 1,500 Model 3 sedans in September and grow that to 20,000 vehicles a month by December." A total of 220 have been delivered. All have been returned to the factory for replacement parts because the car is still being developed and tested! There won't be 1500 total deliveries by Sept
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In 2017 they have so far launched 14 vehicles [wikipedia.org], which is a lot better than the 8 successful and one failure they had in 2016. The R-7 (Russia) has launched 11 [wikipedia.org] and the Ariane (Europe) 5 [wikipedia.org], so they are definitely competitive. At the same time there were 60 successful (and no failure) R-7 launches in communist USSR in 1974.
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OK, you're an EE with 35 yrs of experience, and Elon Musk is a real-world Tony Stark who builds rockets and electric cars. I choose not to underestimate Mr Musk / Stark.
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Speaking of snake oil...this whole video is selling FUD and is all speculation nonsense.
The guy can have all the PHDs he wants but the nonsense 'can't work' claims are idiotic. His implication that making a long vacuum tube is impossible...is idiotic. If we can make one 100m segment, that can be repeated 1000x and you have 100km.
The "vacuum energy" he goes on about? Well yeah, if you use tanks meant to contain liquids under high vacuum as your 'how easy it is to break' example then you're just an idiot
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Echo the other response so far, great post, thanks.
What I wonder about is that the original Hyperloop white paper said "tubes mounted on pylons elevated" over things like farm fields. Now, they're digging tunnels, much more expensive. I just wonder what was wrong with tubes and pylons.
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I imagine the answer lies somewhere between NIMBY and fragility.
Whatever, it shows Mr. Musk is practical. If the "Sci-Fi novel" version of an idea doesn't work, use the one that does.
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The original Hyperloop Alpha plan budgeted standard rates for tunneling for the sections that required it. Musk however began looking into tunneling after Hyperloop came out and found (the same thing I found when I looked into it) that today's tunneling market and contract structures disincentivise radical innovations to reduce costs, and that there's many things that people in the industry already suspect could radically increase tunneling speeds (and thus reduce costs) but have not yet been attempted. He
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The big thing about tunnels is that they give you much better possibilities of getting into town (rather than the periphery like airports, as Hyperloop Alpha did) and maintain straightness in rough terrain. ... an elevated Hyperloop would be passing through far too much built up land to maintain straightness, speed, and low right-of-way costs.
These are obvious problems with an elevated Hyperloop that I and others pointed out here a long time ago (while OTOH many Hyperloop fans were claiming it would be cheap like an oil pipe line). Why has it taken Musk so long to realise it?
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The original Hyperloop plan was to not go into town at all, so it didn't apply.
It also, however, meant that it wasn't as convenient.
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What I wonder about is that the original Hyperloop white paper said "tubes mounted on pylons elevated" over things like farm fields. Now, they're digging tunnels, much more expensive.
They realised or discovered that not everyone in the World is a Musk fan, and is not going to give his eyesore a free pass over their land or house, on pylons or not. The early Hyperloop publicity implied that people would.
Also, whether it is cheaper depends on what is on the surface. It used only to be cheaper to tunnel in cities, but for example the UK in the South East is now so built-up that a large proportion of the Channel Tunnel railway link was built underground.
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Rei is definitely an astroturfer. In a way his posts are interesting in that they seem to give us some inside knowlege of the project, sanitised of course. OTOH he cannot stand the slightest criticism of Hyperloop, much of which he answers on the lines that something will turn up to cover the problem.
All that stuff in his post above about cutting tunnels faster than ever before with the aid of blade cooling etc is really quite irrelevant to the practicality of the Hyperloop concept. Is he smoke-screening s
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New York to DC is about three hours by train; who cares if that gets cut down to 30 minutes?
Basically any person who has to travel from New York to DC on a regular basis. It may sound strange to you, but for most people out there time is valuable.
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If you want to see working mass transfer t systems, visit any other developed country. We already have that. Unfortunately, the stuff was not invented by an US American.
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Yeah, it works in relatively small countries with high population densities. Notice that they're proposing this in the NE Corridor, which is geographically limited and has a high population density. This ain't for Kansas. A universal solution for the USA to mass transit is likely never happening due to the expense of building such a system and having 3 people debark at Kansas City each time a train comes thru. Therefore, using public money to build any of these things is fundamentally unfair to those i
Re: Great idea (Score:2)
True. It makes no sense to have such system in Kansas or North Dakota. Except for Bismark itself, maybe. However, it would work in both costal regions which would fix a lot of transport issues.
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After following way too many 18 wheelers, and being run off the road 3 times in 1 year by big rigs changing lanes without looking (I always respond to "automated trucks" with the question, "Will they also not look when changing lanes?) I fantasize about a hyperloop big enough and powerful enough to accept an 18 wheeler, or several cars and rocket them to their next destination up to 300 miles away, thus relieving a massive amount of traffic from the interstate highway system which is in the process of faili
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In Europe, they put trailors and trucks on trains which can go up to 160 km/h. They use them also for Alpes transit to relieve roads. On distances above 100km this is a faster mode of transportation. With some improvements in the loading process this could even be feasible for shorter distances.
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No, but they have just put a big curse on the project, thats some big oops to come.