More to come?
http://t.money.msn.com/now/sf-to-la-in-30-minutes-is-he-kidding
Methinks this fits in nicely with the discussion we had on doing essentially the same thing coast-to-coast a while back.
Keeping the acceleration and decelleration within the limits of human tolerance is the biggest issue.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
Larry, you expressed my thought on the matter, succinctly.
Johnny
tree68 Methinks this fits in nicely with the discussion we had on doing essentially the same thing coast-to-coast a while back. Keeping the acceleration and decelleration within the limits of human tolerance is the biggest issue.
Methinks that actually raising enough private investor money to build anything like this is the biggest issue...
"I Often Dream of Trains"-From the Album of the Same Name by Robyn Hitchcock
carnej1Methinks that actually raising enough private investor money to build anything like this is the biggest issue...
I don't disagree - but even if the money was there, one has to get past the idea of needing space-shuttle type restraints on both ends of the trip.
tree68 carnej1Methinks that actually raising enough private investor money to build anything like this is the biggest issue... I don't disagree - but even if the money was there, one has to get past the idea of needing space-shuttle type restraints on both ends of the trip.
From what I've read about the various "tube train" hyper high- speed proposals the acceleration/decelleration phases are supposed to take place over a long distance and period of time so the G forces acting on passengers would supposedly not be excessive. Of course, that may pose some difficulty if there is a high volume of traffic in the tube you are traveling in, a "rear ender" would be ugly, to say the least...
Loopie Doopie Doopie Doop...Doop Doop Dee Doop.
http://www.businessweek.com/articles/2013-08-12/revealed-elon-musk-explains-the-hyperloop
Elon Musk strikes me as a dreamer who is enamored of "Gee Whiz" technology and thinks that human progress occurs only when that technology is developed, whether there is a demand for it or not. He has opined that human progress slipped when the Concorde was retired from commercial airline service and a replacement supersonic airliner had not been developed.
CSSHEGEWISCH Elon Musk strikes me as a dreamer who is enamored of "Gee Whiz" technology and thinks that human progress occurs only when that technology is developed, whether there is a demand for it or not. He has opined that human progress slipped when the Concorde was retired from commercial airline service and a replacement supersonic airliner had not been developed.
They said the same about the Wright Brothers and their various contemporaries who so very foolishly proposed to fly people through the air at hundreds if not thousands of feet above the ground. Imagine that, and from two high school dropouts who owned a bicycle repair shop. If anything, Musk may be slightly ahead of his time. This will happen, IMHO.
This country was built by dreamers, and every one of them was mocked by people who said it couldn't be done.
“People who say it cannot be done should not interrupt those who are doing it.”
― George Bernard Shaw
Dave
Lackawanna Route of the Phoebe Snow
As Larry (Tree) remarked almost a month ago, there is the problem of acceleration and deceleration that seems to be ignored in the promotion of this means of transit. I saw nothing of it in the account in this morning's paper.
Wouldn't it be more economical, and only slightly less of a technical reach, to just use Doc Brown's machine from Back to the Future?
Thanks to Chris / CopCarSS for my avatar.
Deggesty As Larry (Tree) remarked almost a month ago, there is the problem of acceleration and deceleration that seems to be ignored in the promotion of this means of transit. I saw nothing of it in the account in this morning's paper.
The design Musk is promoting has a top speed of around 750 MPH which is barely transonic (MACH 1), the G-load would not require "Space Shuttle harnesses" for the passengers....
As far as some hypothetical far future 3,000 MPH "transatlantic tubetrain", it would have to be designed with long acceleration/deceleration phases, it could not launch out of the station like a horizontal Saturn V rocket..
Regardless, the technological and financial obstacles that must be overcome for any such system to be built are so huge that we may as well be debating Starship designs...
I believe what this will be most successful at is separating investors from their money.
Have fun with your trains
carnej1 Deggesty As Larry (Tree) remarked almost a month ago, there is the problem of acceleration and deceleration that seems to be ignored in the promotion of this means of transit. I saw nothing of it in the account in this morning's paper. The design Musk is promoting has a top speed of around 750 MPH which is barely transonic (MACH 1), the G-load would not require "Space Shuttle harnesses" for the passengers.... As far as some hypothetical far future 3,000 MPH "transatlantic tubetrain", it would have to be designed with long acceleration/deceleration phases, it could not launch out of the station like a horizontal Saturn V rocket.. Regardless, the technological and financial obstacles that must be overcome for any such system to be built are so huge that we may as well be debating Starship designs...
While I realize 'passengers' would not accept it, Top Fuel and Funny Car drag racing cars routinely accelerate from 0 to in excess of 300 MPH in less than 1000 feet and under 5 seconds. (because of the speeds being reached by these top class cars - the competitive track has been reduced from 1320 feet {1/4 mile} to 1000 feet several years ago). Needless to say, such acceleration would not be conducive to breaking out one's personal electronics and accesing Wi-Fi.
Never too old to have a happy childhood!
Some of you were talking about decelaration above. I have a question; just how do you get it stopped exactly?
It used a linear induction motor to get things moving with occasional mid-route boosts. Lots of roller coasters do this. Nothing weird or new about it. Acceleration can be as gentle as needed. Actually, gentle is easier - lower power requirement.
It uses suspension like an air bearing. Nothing weird or new here, either. Just bigger.
It uses a suspended tube for a guideway. This is new. It needs the guideway to be partially evacuated. This is really new. It uses a compressor on the front end to "suck" in the air in front of the train and push it out the back through the air suspension, so the thing essentially coasts with little friction between induction motor boosts.
The suspended tube guideway is designed for easy alignment and to be earthquake tolerant.
There are a gazillion details where the devil can pop up. He's thought through a bunch of them but has "wave the hands" kinds of answers. Fair enough. This isn't a complete design - just a concept/feasibility study at this point.
It's pretty wild....but not crazy. I think I'd rather spend the day and drive than climb aboard.....but that's what people said when RRs first appeared, too.
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
After every lawyer in America is dead this possibly has a chance, science not withstanding. We will all be NIMBYs when they want your house, your town, your city because a support is need right there as it has the tube needs to be in a straight line. I'd be willing to bet the approval process to move power lines, national parks, lakes, and who knows what will take a century at least. And how noisy will it be on the outside as it whizzes by at 600+mph?
overall Some of you were talking about decelaration above. I have a question; just how do you get it stopped exactly?
Two ways. You can use the linear induction motor in reverse. Or, there is an emergency friction brake of some sort. Either way, you don't want to do more than about 0.1G for regular service braking.
john_edwards After every lawyer in America is dead this possibly has a chance, science not withstanding. We will all be NIMBYs when they want your house, your town, your city because a support is need right there as it has the tube needs to be in a straight line. I'd be willing to bet the approval process to move power lines, national parks, lakes, and who knows what will take a century at least. And how noisy will it be on the outside as it whizzes by at 600+mph?
Doesn't have to be dead straight. The alignment of I-5 is mostly good enough. Noise is a good question, but since tube is partially evacuated and no direct contact from vehicle to tube, it might not be very noisy.
Jim200Elon said that it is a Concorde and railgun and with an air hockey table. That suggests to me that it is a Mach 2 aircraft mounted on a railgun with an air cushion and launched in a hyperloop, high altitude ballistic loop, to the target city. It could land conventionally like the space shuttle, or even better, align with the target city's railgun and recharge the railgun's supercapacitors.
Not close. Read the guy's paper that came out today.
You regularly sit in your automobile as you accelerate from near 0 to 60 or 70 mph entering the highway. Is that uncomfortable? It takes you about a quarter of a mile. If that same rate of acceleration is maintained for 4 more miles you are at his promised speed.
This argument is a red herring.
You can read the whole paper here: http://www.teslamotors.com/sites/default/files/blog_images/hyperloop-alpha.pdf
His presentation identified Interstate rights of ways as being where initial construction should be - that being the case, I don't know how well the concept would mesh with the turns that exist on the Interstates. 70 MPH and 700 MPH are worlds apart.
For a "back of the envelop" calculation of the acceleration needed we propose:
Accelerating for 1/2 the trip (15 minutes = 1000 seconds to make life easy)
Distance to accelerate 1000 miles (5,000,000 feet again to make life easy)
d = 1/2 a t^2 so the acceleration needed is a = 2 d / t^2 = 10,000,000 feet/ (1,000 * 1,000) sec^2
a = 10 ft/sec^2 which is equal to gravity. Not a problem to accelerate faster than this and reach a cruising speed faster.
PETITNJ
There is a slight error in your calculations. The acceleration due to gravity is 9.8 meters per second squared, or 32 feet per second squared. It's easy to get them mixed up - I've done it a few times.
10 feet per second^2 is roughly 0.3 gravities, which is not that bad, really. A quick acceleration onto a highway in a car will give you and acceleration of more than 0.3 G.
Based on 0.3 G, the total acceleration experienced by the rider would be about 1.1 G. (1 G down, 0.3 G back, use the Pythagorean Theorem.)
This is a really great idea, but likely nothing will come of it because of problems getting permits, buying land, governmental restrictions, and funding. Too bad. Maybe in 50 years we will have something like this. This is definitely and idea ahead of its time.
S&S
Modeling the Pennsy and loving it!
BaltACD john_edwards After every lawyer in America is dead this possibly has a chance, science not withstanding. We will all be NIMBYs when they want your house, your town, your city because a support is need right there as it has the tube needs to be in a straight line. I'd be willing to bet the approval process to move power lines, national parks, lakes, and who knows what will take a century at least. And how noisy will it be on the outside as it whizzes by at 600+mph? His presentation identified Interstate rights of ways as being where initial construction should be - that being the case, I don't know how well the concept would mesh with the turns that exist on the Interstates. 70 MPH and 700 MPH are worlds apart.
There's quite a bit in the paper about alignment. The worst problem is the southern end approach to the LA basin.
Good point about Nimby's but if such a thing were built why would you think it would be loud?
It's a sealed tube with much of the air pumped out and the vehicle generates very little friction so I don't see what would cause excessive noise..
I've read the PDF, but can't find any reference to this problem: the compressor is a single point of failure. The compressor is needed to:
There's a battery powerful enough to last the entire journey, so electrical power supply failure isn't a problem, but what if there were a mechanical failure? It seems to me the pod would rapidly decelerate to a halt (pressure build up in front and friction below) - I don't know if this would be rapid enough to cause injury, but it sounds unpleasant. Also the oxygen masks would be needed as there's no longer an air supply.
In addition, all the following pods would need to stop. There's a reference to an 'emergency mechanical braking system' (4.5.3), though it isn't explained. It seems to suggest that pods could trundle to their destination on wheels, but that could take several hours, couldn't it?
Compressors are simple mechanically and well understood (jet engines), but they still fail occasionally. If failure rates were comparable with passenger jets (a bit harsh, the environment is more benign than that), I estimate about one a month for the 'fleet' of pods.
Our community is FREE to join. To participate you must either login or register for an account.