I thought about mgrant's similar idea, and it made me thinking about an old idea of mine. A trans-atlantic undergound train, that will travel under the ocean, through the ground. Building the tracks for this train, will involve some heavy drilling through earth outer shell (lets say from Britan to the u.s.), and placing the shaft, which in the train will move. The idea is that the train itself will be some kind of a pod. It will Travel through the shaft in high velocities, using earth's gravity to accelarate, and after passing through the middle point of the shaft (in which the gravity will start having the opposite affect of slowing the pod down), using it's gained speed, and some kind of propulsion (to compensate the friction in the shaft), in order to reach the other side. Another possible way is to aceelarate the pod even more in the first half, and afterwards using it's momentum to continue (relaying on earth's gravity to slow down).
This, in theory, has huge advantages over normal planes and ships, including using gravity as a propulsion method, and extremley shortened travel time between distant locations.
I never read that book (Supertrains). Anyway, thumbwax, what are these strange questions? This is a theoretical idea. I didnt ask no physicist about it.-- Icarus, Apr 14 2001 Transatlantic Tunnel http://www.amazon.c...os/ASIN/B00001U0GC/ [egnor, Apr 14 2001, last modified Oct 04 2004] A Transatlantic Tunnel, Hurrah! http://www.users.ze...n/transatlantic.htm [egnor, Apr 14 2001, last modified Oct 04 2004] Supersonic trans-Atlantic rail tunnel. http://www.prologue...uk/angel/train.htmlOoooh! [angel, Apr 14 2001] The transatlantic tunnel is being planned! http://www.ajclewis.net/links/trans.htmlater, I realise it's the same story as [angel] linked. [lewisgirl, Apr 14 2001, last modified Oct 04 2004] Supersonic trans-Atlantic rail tunnel. http://www.angel.no...my.co.uk/train.htmlOoooh! [angel, Oct 04 2004] gravity train http://en.wikipedia.../wiki/Gravity_trainwiki's entry on this idea. [the great unknown, Jun 20 2007] Operating costs: advantage train (debatable).
Capital costs: advantage plane and ships.
You don't have to build tracks to get planes and ships across the ocean. Sky and water are plentiful.-- Wes, Apr 15 2001 The Chunnel cost $15 billion. The tunnel is 31 miles long; 23 of those miles are under 150 feet of water.
If we assume that it is no more expensive to drill under five miles of ocean than under 150 feet of channel (which it's not), and that it is no more expensive, per mile, to design or build a tunnel that extends for thousands of miles (which it's not), and if these supersonic pods are free (which they're not) then the cost of a transatlantic tunnel would be $1.5 trillion.
It's hard to estimate the flexibility in demand for intercontinental travel, but I will point out that the capital cost of the tunnel exceeds the market capitalization of all the world's airways by an order of magnitude.
I don't think private capital markets have ever funded any project this big (the Chunnel was considered a pretty big deal, and had 200 funding banks). Governments have, of course, but I don't see why they would in this case.
Formidable technical problems include building this high speed train, dealing with the geothermal heat, construction logistics (How do you carry supplies thousands of miles to the drilling point? How do you get the rock back all those thousands of miles?), the steep continental shelf drop-off (even at a 10% grade, which is very steep, you'll end up going dozens of miles inland), ...
At least with a floating tunnel, you can build it in pieces, use ordinary ships to get to the construction site, and have air vents every so often.-- egnor, Apr 15 2001 This is idea is in/stolen from one of my favourite, yet childish, books: Supertrains, it has a picture which fits the exact description of your 'idea'. 2 shafts at x degrees meeting at the centre of the earth, the train station had an airport type setup, and the pod was 5 stories high, and the shafts were vaccumed.
[Maybe a mylar flexitunnel that could adjust to the earth groaning, with hundereds of pods that could take a family of four would be better...]-- [ sctld ], Apr 15 2001 wot about plate techtonics?-- edski, Apr 15 2001 Would your eardrums burst or merely 'pop'? Would it be kind of warm? Would Lloyds of London insure this? Would you need physicians approval? Would a waiver be in effect? Would H.G. Wells...-- thumbwax, Apr 15 2001 Plate motion is not very fast, and (I believe) it occurs by slippage along fault lines. People who drill tunnels (and even people who build aboveground railways) have to deal with fault motion (and the accompanying earthquakes) already; this is no different, though a 3,000-mile tunnel will necessarily cross more fault lines than a 30-mile tunnel.-- egnor, Apr 15 2001 Did you hear about the trouble the French and English had, when trying to make a connection between the tunnels in the middle of the Channel? They missed by quite a long way. And that's over a distance of 30 miles. Make the distance 3000 and the chances of missing become huge. Still, worth a try....-- PotatoPete, Apr 17 2001 or for the same amount of money you could just invent transporters like out of Star Trek.-- tkeyser, Apr 17 2001 No, we couldn't.-- egnor, Apr 21 2001 See link from yesterday's Daily Mail.-- angel, Jun 27 2001 [PotatorPete] Where did you hear that? From what I remember they were only a few inches out.-- hippo, Jun 27 2001 Concorde is three times as fast as a 747 but very few people are prepared to pay the £1500 premium. This train will either have to be stupendously faster or considerably cheaper to compete, neither of which seems likely.
For the $1.5 trillion that [-egnor] estimates you could probably provide anyone who wanted it with such good remote video conferancing technology that none of the business sector would need to make the trip at all.-- gravelpit, Jun 27 2001 [gravelpit]: See my link; is Mach 3 fast enough?-- angel, Jun 27 2001 see link. A case of "seen a news story, think there must be something about this on the 1/2B... got it!"-- lewisgirl, Jul 08 2001 My god! I want to scream! In lewisgirl's link, the MIT guy says about the tunnel being a maglev within a vacuum, which is an idea that i passed by a NASA guy. I said it could bring military folk from their various bases to the pentagon in minutes, and it's described exactly as i described it to the nasa guy! Aaaah!-- [ sctld ], Jul 09 2001 chill, man.-- lewisgirl, Jul 10 2001 [angel]: no, I don't think mach 3 is fast enough. This would allow you to do London to New York in about an hour and forty minutes and on top of that you'd still have the overhead of check-in and baggage reclaim. If tickets for this train were a lot cheaper than concorde, you might attract some custom but it seems very likely that they would be much higher.
I think that now that we are down to two hours to cross the Atlantic, incremental advances in speed won't be enough to justify a price premium. Instantaneous teleportation would be but I can't see the train travelling *that* fast...-- gravelpit, Jul 16 2001 Air transport has already cornored the market in trans Atlantic transportation. I doubt that it willl change. Even if a trans Atlantic train was built not enough people would use it to make the project worth the cost.-- wood2coal, May 06 2002 "On that train, all graphite and glitter Powered by the sun 90 minutes from New York to Paris Well, by '76 we'll be A-OK."
- Donald Fagen, "I.G.Y. (What a Beautiful World)"
Requoted from a previous life.-- waugsqueke, May 07 2002 Just saw an interesting documentary on a proposed train bridge linking Asia and the US via the Bering Strait. Still pie in the sky, but ever so slightly less so than a trans-Atlantic train.
And the end result would be the same: you could go from London to New York by train.-- DrCurry, May 01 2003 See my post, Bering Strait Bridge for a better, safer, and cooler way for a similar idea.-- empty89, Jan 07 2004 agree, sctld, this idea is baked. the freaky cool thing is that no matter how long the tunnel is, the ride will always lasts about 43 minutes. the two biggest engineering problems is the friction & the molden rock beneath the mantle.-- the great unknown, Jun 20 2007 Great idea!Because by the time its finished, we the British still wont be allowed in your country because your not going to grant us visa's!-- S-note, Jun 20 2007 random, halfbakery