…As we see the subject creates a bunch of comments…Don’t know about interest, serious interest…Seems not many on here believe it’s even near remotely possible in much of any time frame. And of course I too believe nothing remotely like is being discussed will happen in any possible time frame ahead that we might think about. Just too many engineering and cost mountains to climb and I’m not sure what reason could be dredged {whoops}, up to even think about trying such an act. I’m thinking about all that compressed air ahead of the {piston}, whoops again…train at 5000 mph, until it gets hot enough to ignite like a diesel…Just add a little seepage of sewer gas for the fuel…Believe it might be a lot easier to go to Mars with humans, but then again, why do that ether. That can be done unmanned. Of course some of this is tongue and cheek…
…I see 4449 thought of some of the same stuff…
The plan is for a vacuum tunnel surrounded by a pressurized one, the train in a pressurized tunnel would encounter no air resistance. I.e. there is no air the cylinder. In a vacuum the train could be shaped like a brick and lose no speed.
…There is not enough vacuum pumps in the world to pump a 3000 mile tunnel to a vacuum…
I think the channel tunnel’s design alleviates the displacement of air problem by allowing it to transfer across to the parallel tunnel (there are two tunnels connected together at intervals with access ports).
Oh there will be a vacuum all right…caused by the sucking of money right out of someone’s wallets…
…Wasn’t there a service tunnel too…{smaller than the rail tunnels}, between the two rail tunnels…and all where {are}, connected.
…Yes, that big sucking sound as Ross said a bit earlier in time…
If the train has an emergency stop, I hope you can hold your breath for a looooooooooong time!
What really gets me is that someone actually convinced a producer that this was a viable idea and got the money to make this into a TV show. Now I like extreme engineering ideas as much as the next person but this is so financially unviable as to make my head spin.
If they bought this I should contact them with my Casino on the Moon scheme!
Some engineering thoughts on the proposal:
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Evacuating the tunnel of air is done to reduce friction and the “piston effect” as was mentioned above. It’s not a nicety, but required for such a long tunnel.
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The tunnel will have problems whenever it crosses a fault line, as ANY shift of the trackage will dramatically affect the train. Remember Newton’s Laws, and the train is going FAST. Picture the results in your mind…
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The faster a train is flying, the straighter the track has to be, otherwise it’ll derail. Even a magnetically levitated track has this problem. Laying track for a 1000 MPH train would require incredible precision. Want the train to go faster? Lay straighter track.
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How would you negotiate the mid-Atlantic Rift? That’s the section of the Atlantic sea floor that’s seperating several centimeters a year with lava flowing all the time… Remember that little obstacle? Should be interesting to say the least.
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You must power the train the entire length. Trying to operate a 3000 mile powerline while maintaining proper voltage will be a feat comporable to building the tunnel!
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How will you plan on emergency evacuations of the train? Remember the tunnel is evacuated, and people will need air, fresh air. A tunnel that size will require LOTS of air to be pumped in, and then LOTS of air to be pumped out to return it back into service. As a minimum you’d have to have the tunnel built in sections, dual track, with emergency doors to block the air flow wen the tunnel is pressurized. You’d probably have to build parallel tunnels, and dual track both of them. You’d have to have seperate evacuation shelters with fresh air supplies, food, water, etc. People could be stuck down there for days at a time.
I think hypersonic aircraft for passenger service will happen sooner.
Mark in Utah
Honey, I’m going to Paris to pick up some champaign for dinner. Do you want anything else while I’m there?[:o)]
…Just jot it down on the side of the ledger containing Pipe Dreams. Other ways to move people super fast will be developed. Either on water surface or more likely supersonic aircraft of some future design…
This whole idea is nothing but a pipe dream.
Harrahs’ has already teamed up with the Luna band of fairly pale skinned Indians…apparently they had claimed that they were the original inhabitiants of the Moon and were displaced to a comfy office in LA by the US Government. They are seeking to build a casino there to make up for past maltreatment at the hands of the IRS… Sorry Vic…
Pipe dream: It’s a big pipe, and they’re dreamin’…
Mark in Utah
Submarines aren’t pressurized. Not in a sense like what I think you mean. The ‘atmospheric’ pressure inside a sub fluctuates based on several things, time since last ventilation with the surface, compressed air usage, air compressor usage, taking water on or off in the variable ballast tanks, things like that. but it is always around 14.7 psia. a small difference in pressure across things such as doors, hatches, and ventilation valves, as you probably know, will make them difficult and thereby hazardous to operate.
As far as the compression inside a tunnel of moving trains, you might as well built a ventilation tunnel parallel to the train tunnel, of comparable size, to minimize the effects of it. Going with the floating tunnel concept, of course.
With further thoughts, why bolt it to the ground?? Use pylons with variable ballast (in an ocean going sense, not a railroad sense) hovering around 500 feet deep. The effects of waves and tides will be minimized, and you could have them pump water out when a train neared, and added its weight, and then pump water back on after it had left.
I think we’ll see the Earth to Orbit Space Elevator long before we see this pie-in-the sky! At least its scientificlally and finacially feasable with todays technology!
Dan I’m a member of the Heckowe tribe, we came to California thru a blinding dust storm back in the 30’s, took one look around and proclaimed “We’da’Heck’o’we?”
A much better question: Who in the world in America would want to go to Europe? We are content to sit here. It will just bring stupid (no offense to our very smart friends on the forum) Europeans to the US.
vsmith: I think you mean the '30s not the 30’s. Unless you came from the future.[(-D]
James[C):-)]
Let’s give it up for Vic folks…he’ll be here all week for two shows a day…Up next is Rico Gogo and his dancing apes…
WOW, I didn’t realize that this is already BUILT! Apparently construction started in the 1940’s and the tunnel will open in 2009!
http://www.atlantictunnel.com/
Now if only I can get directions to the Cape Cod Canal tunnel (a joke only New Englanders will get)…
PS. If the purpose of the above website is to grift money from honest (but gullible ) folks it’s creators should be thrown in the Slammer…otherwise it’s a clever practical joke…