I know maglev trains can go a few hundred mph, some test mag-lev systems go much higher, but can a maglev system, maybe in a partial-vacuum tunnel, be stable enough to run something at, say, Mach 10-ish safely?

I'm imagining a ramjet plane going through a tunnel like that when at about mach 7 it suddenly starts vibrating, or th track kinks ever-so-slightly, and the metal fins in the coil array slightly tap the coils: at mach speeds. They'd get incinerated, melted, maybe torn off, leaving at least part of the plane bouncing around in the tube at insane speeds with no support to keep it from slaming into the tunnel walls. Cataclysmic is the word that comes to mind.

Just a thought :D

I don't think so. It would be highly unstable at those speeds.

If you want a bigger safety margin for 'kinks' etc then you could simply increase the distance that the hypersonic train/plain is from the magnetic tube by increasing the diameter of the tube. Also you can't have it changing direction on a sharp curve so the tube would be nearly straight. As a result of increasing the distance that the magnetic field acts over [(radius of tube) minus (radius of transport vessel)] you would have to greatly increase the strength of the field which requires a fair bit more power (but only the area repelling the train/plane needs to be active which cuts power requirements drastically).
So apart from the scale of the project and the power requirements it would work just fine. :)

weed_eater_guy ......

Why do you want to travel that fast? Think of how much energy it will take to get something to that speed and maintaining a vacuum as your saying at the same time, highly unlikly IMO.

People would be willing to pay a lot of money to be able to get across the atlantic in hardly any time at all. Money is sufficient reason for just about anything.

People would be willing to pay a lot of money to be able to get across the atlantic in hardly any time at all. Money is sufficient reason for just about anything.

I don't think so. Airlines are floundering. What makes you so sure people want to travel?

Airlines are floundering because the business outgrew the market. If you had half the number of airlines, the pie would be divided into a fewer number of slices and the remaining businesses would be rolling in cash. Crap is still being weeded out after the airline deregulation.

On the other hand, if you have one tunnel run by one company that can promise you extremely quick delivery to another continent.... that company would be rich beyond its stockholders' wildest dreams.

But a vacuum tube the length of the Atlantic? Not only would its cost run into the 100s of billions of dollars, but it would be a terribly easy target for terrorism, sabotage or just plain vandalism.
And hideously dangerous.

the idea I had was a maglev launcher tube for shooting spacecraft at mach speeds to save some of their onboard fuel and make things cheaper. think about it, most of the energy is put in to the ship when it's accelerated to hypersonic speeds, which comes from a ground-based power source, (electrical energy is still much cheaper than rocket-fuel energy). The tube would be straight, either angled off the ground or suspended several kms above the ground, and it'd be considerably long, maybe a hundred-miles-ish to get mach 10. turns?! at supersonic speeds?! sounds like jackass el grande!