Talk:Transatlantic tunnel

Architecture Start‑class Low‑importance

	Architecture portal This article is within the scope of WikiProject Architecture, a collaborative effort to improve the coverage of Architecture on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.ArchitectureWikipedia:WikiProject ArchitectureTemplate:WikiProject ArchitectureArchitecture
Start	This article has been rated as Start-class on Wikipedia's content assessment scale.
Low	This article has been rated as Low-importance on the project's importance scale.

For an April 2005 deletion debate over this page see Wikipedia:Votes for deletion/Transatlantic tunnel

This article was nominated for deletion on September 8, 2007. The result of the discussion was keep.

This should be merged with Vactrain.

No, but it should link to it. --Golbez 07:22, 24 August 2006 (UTC)[reply]

It is requested that a photograph be included in this article to improve its quality.
The external tool WordPress Openverse may be able to locate suitable images on Flickr and other web sites.

Upload

Stability of a submerged tube?

A text I read regarding ordinary high-speed trains said that the high-speed railways need very high stability because there can't be "bumps" at a high speed. Therefore a suspension bridge is not usable at high speed. If one is neccesary it must be travelled at lower speed. What about travelling submerged tubes at above 1000 mph? Maybe one trains causes the tube to move, which might make it very unpleasant for the next train? --BIL (talk) 20:58, 20 May 2008 (UTC)[reply]

Indeed, such a tunnel or tube is so far beyond current fiscal and engineering capabilities that problems like that seem downright mundane. Presumably such a tube would have integrated mechanisms for active stability, and trains designed specifically to deal with rail movement, rolling of the tunnel due to its weight, change in buoyancy, etc. Or perhaps solving those are so difficult, a magnetically levitated (MagLev) might be justified. —EncMstr (talk) 22:30, 20 May 2008 (UTC)[reply]

Maglev does not solve the problem since the railway is still influenced by a force from the train (Newtons third law). Maglev needs centimeter accuracy for the "railway", and would get serious problems with a submerged tube. If air travel still exists, e.g. year 2200, why is a maglev across the Atlantic justified, having the cost in mind? Isn't air travel better? --BIL (talk) 20:45, 22 July 2008 (UTC)[reply]

As long as the effect is behind the train, who cares? Presumably the next train is an hour or more behind, long enough for the system to stabilize.

I thought the whole point of a high speed (1000+ mph) tube was for it to be in a near-vacuum for energy use advantages.

I remember another flavor of proposal (don't remember where, but it was 15–25 years ago) which would mostly evacuate the tube with the train sealing the cross section. With the train at one end, it compresses the air between the station and the train. As soon as the brakes let go, the air pressure would accelerate the train toward the far end, initially in near-vacuum. As the train approached the other end, the bits of air ahead of it would compress and slow the train to a stop just as it reached the station, with a nearly full vacuum behind where it just came from—almost a perpetual motion machine. Just needs a little energy added to replace the thermal losses magnified by Boyle's law. —EncMstr (talk) 21:00, 22 July 2008 (UTC)[reply]