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Elon Musk Begins Digging a Hyperloop Tunnel In Maryland (baltimoresun.com)
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.
Title says "Begins Digging" yet he's only now been "granted permission"?
Wrong headline is wrong.
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 number of people fast and efficiently, I would love to see the business plan on this tunnel, how many people can be moved in a 24 hour period? whats the cost per passenger? whats the maintenance cost? the cost to maintain the vacuum in a ten mile line, yes it’s underground, but your going to need a lot of emergency exit points along the route, and each air lock is another potential vacuum breach.
The Concord showed us fast is not always profitable.
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.
I'll BUILD someone to replace you. Some kind of gamma-powered monster, with a heart as black as coal!
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.
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.
I'll BUILD someone to replace you. Some kind of gamma-powered monster, with a heart as black as coal!
The Inter-County Connector intersects with the BWI Parkway about five miles away. Getting that highway built took fifty years, got hung up for years on environmental studies and the Federal Government withheld funding. The state house is dominated by Democrats and Hogan is a Republican. Oh, and the Feds won't approve it's construction into DC? I doubt this is going to get done with little more than a few utility permits. Good luck though.
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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.
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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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 miles, so the six accel/decel periods would cover 88 miles. At 760 mph for 11 minutes, you'd cover 139 miles, that adds up to 227 miles.
So, 1/4 gee acceleration is sufficient, and while what's about 3X the acceleration of a subway car, it's very tolerable. It might actually be more comfortable to do 1/2 gee for 66 seconds, or 1 gee for 34 seconds, on the theory that it's better to spend less time accelerating harder, to have more time at constant velocity.
Tell me oh /. Masters of the Universe where I am wrong?
In your initial assumption that loading and unloading a hyperloop car is like loading and unloading an airplane. Are there any other easy problems you'd like solved?
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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 bastards with a backbone, not asswipes with phony social agendas like the Google or Facebook CEOs.
lucm, indeed.
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.
lucm, indeed.
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" Hyperloop test winner was a 200 mph (320kph) electric car that could not carry any passenger since it was too small and did not depend on the vacuum.
Rather than me go into details why the project is stupid please view (there are others) the following YouTube Hyperloop debunk. In case you think the guy is a crackpot he does have a Ph.D. in science but then again human gullibility knows no bounds especially when something sounds attractive (ie. Solar Freaking Roadways) but can be proven by Science and Engineering that they are impractical.
What next for Elon Musk? A proposal for "Tourist trips to mars using cold-fusion powered flying saucers?"
There ain't no such thing as proprietary standards only proprietary formats. Standards are by definition open.
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 which would send out a shockwave traveling at the speed of sound and anything in the tube would be pulverized.
Rather than me waffle on here is a Hyperloop debunked video. There are others on the Hyperloop as well as other popular but impractical pseudo science Snake Oil.
There ain't no such thing as proprietary standards only proprietary formats. Standards are by definition open.
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.
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.
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.
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 thankful I don't live in that state. When designing an electronic grid everything is up for grabs in the feasibility stage but you also have to be practical and look at the economics as well. Just going solar using photovoltaic cells is plain stupid since you then will have to consider how the store the energy when the sun goes down and batteries just can't cut it at least not economically. Although if you can show an Engineering proof I am amenable to a change of mind.
Landing a rocket tail first? You do know that any rocket can be designed to land tail first it is just not economically viable to do that especially when you consider that the chances of a failure are so much higher than if you came to land like an aircraft or use a parachute. Like it or not rocket flight is expensive and the chance of getting into orbit is reasonably high at 92% but landing is a totally different matter. I will let you research that since us dinosaurs are incapable of using a four-function calculator much less run a Google search.
Personally, I don't mind admitting I am wrong and taking it on board if you can show I am wrong but calling someone a dinosaur and name calling when you don't even know them that is the sort of thing an SJW would say and for your sake I would refrain from saying things like that in the boardroom where us raptors reside.
There ain't no such thing as proprietary standards only proprietary formats. Standards are by definition open.
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 pretty good idea as to the cost of those tubes. FWIW the original document gives an estimate of about $4 billion for tubes, pumps, pylons, and stations, though I do think it's a shame the costs were not separated out more.
you also have to take into account the thermal expansion coefficient of steel.
Yeah, this is my biggest problem with the proposal, for above ground construction anyway. There are materials and methods that might get around the problem but by my 'uninformed' reckoning they massively increase the cost and complexity of the tubes. Building the tubes in an underground tunnel, however, virtually eliminates the expansion problem, as temperatures below ground are remarkably uniform (as in unaffected by day / night and seasonal cycles). As other posters have mentioned this does hugely increase the construction cost and build time, though much of the tunnel construction could be done using the 'cut and cover' method which would gives substantial gains over boring the tunnel.
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.
Yeah, you probably shouldn't believe everything you see on YouTube, especially stuff which is as disingenuous as some of the videos posted by Thunderfoot. 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. Woah, scary stuff, no? Oh wait, no it's not. Modern engineering solutions turn the miraculous into the mundane on an almost daily basis. You'll also note that, despite numerous micrometeorite hits, the ISS is still in one piece, and that actually is operating in a vacuum, unlike the proposed hyperloop tubes, which are just very low pressure.
Rather than me waffle on here is a Hyperloop debunked video. There are others on the Hyperloop as well as other popular but impractical pseudo science Snake Oil.
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. He is exactly the sort of person I envisage saying, with patronising smugness, "What a ridiculous idea, wood is heavier than air so it's obvious to anyone who has eyes that it simply will not get off the ground". True, he has raised one or two valid criticisms, but that doesn't mean the problems are insoluble. His mockery, and his apparent assumption that he's smarter than everyone else who's thought about the subject makes it hard to watch anything he posts though.
With you until you said "Gates".
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 meters of water. Sure a decently prepared vacuum container will be able to take these pressures but what has been proposed is a vacuum tube that is well over 100km long and is capable of taking a shuttle or multiple shuttles with human passengers that are supposed to be traveling at around 1100kph (700mph) and all it takes is a minor fault or rupture and you have human salsa. It must be noted that no country in the world has ever come close or has even considered what has been proposed.
"Modern engineer solutions turn the miraculous into the mundane?" If you look at electronics then sort of yes but I was using computers with decent graphics back in 1983 and while computers have got more powerful and smaller they still have not changed that significantly since the 1980's. Do you know that in the late 1950's the worlds first hovercar was built Curtiss-Wright Model 2500 Air Car however even today I don't see any hover or flying cars on the road. You can even look at the Concord and I will leave it up to you to find out why we don't have supersonic passenger jets anymore.
As an Engineer, I am all for science and advancement but I also like to see the evidence (you know the Scientific Method) before I agree or disagree. Jumping on-board for the hype is plain stupid and can be expensive.
As for annoyingly smug, I don't find Thunderfoot that way since he always provides evidence and that is what I care about.
There ain't no such thing as proprietary standards only proprietary formats. Standards are by definition open.
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 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 proposal was for a route that ran from LA to SF, so roughly 560 km one way, or a 1120 km circuit. You don't find it funny, as an engineer, that you clearly haven't read the proposals, or follow on documentation, but you're happily telling us what you think they said?
...supposed to be traveling at around 1100kph (700mph) and all it takes is a minor fault or rupture and you have human salsa.
Yup, and when a car crashes at 120 km/h, when a train derails at 200+ km/h, when a plane depressurises or crashes people tend to die too. It's not possible to be so risk averse as to avoid all possibility of harm, because if you were to try you'd starve to death from fear of choking. I'd say much of the fear surround this idea is fear of the unknown - a natural human reaction, even if a tad 'over-sensitive'.
You can even look at the Concord and I will leave it up to you to find out why we don't have supersonic passenger jets anymore
Mostly it was because it couldn't fly supersonic for a great deal of its routes, due to the sonic boom. It was also a bit of a gas guzzler. So, it didn't save as much time as was originally envisaged, and it was very expensive. In other words it stopped flying due to economics, rather than any technical reasons. Again, what point are you trying to make?
As an Engineer, I am all for science and advancement but I also like to see the evidence (you know the Scientific Method) before I agree or disagree
You'll excuse me for saying so, but your posts don't seem to suggest this. It rather seems, by posting the links you have, that you have very much decided already.
As for annoyingly smug, I don't find Thunderfoot that way since he always provides evidence and that is what I care about.
The most visceral demonstration I think I saw him give was him putting a ball bearing in an evacuated glass tube, then having snapped the end off, and watched the ball bearing shoot down the tube and smash through the end he suggested that this showed that any hole in the hyperloop tunnel would 'wreck' the transit pod and or tunnel and kill all the passengers...
So let's examine this demonstration and the claims:
Did snapping the end off the evacuated glass tube, causing air to rush in, destroy the rest of the glass tube? No, it did not
Was the cross sectional area of the glass tube roughly twice that of the ball bearing? No, it was not
Is a small ball bearing in any way equivalent to a 15+ tonne vehicle when considering the effects of a certain mass of air hitting it? No, not really
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
So tell me, what 'evidence' is he providing exactly?
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.