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Are you talking about this Sky Ramp
or this Magnetic Launch System
There was a site that had done some work on a maglev track to launch directly to orbit. www.maglev2000.com (the site seems to be down now.) The maglev track for a manned launch to orbit (4g max acceleration) is over 500 miles long!

I know it's off topic, but boy could the US have some awesome super-fast railways if it wanted! There was talk a while back about putting one in down in Florida somewhere. My recollection is that is was going to be a MagLev train too!

It's obviously not going to be a replacement for the speed of travelling coast to coast or similar long distances, but it could indeed make sense for shorter journeys. Think about the speed of travelling from the centre of London to the centre of Paris using the Chunnel link. This compares very favourably with the flying times.

Exactly.

As expensive as it is to get mass up into orbit, which would be cheaper:

Shuttle weighs 4.5 million pounds
Hubble telescope weighs 24,500 pounds

Cost per pound to orbit is something like $10k per pound, low ball.

So launch costs for a new hubble would be about $245 million.
Launch cost for the shuttle seem to run around 1Billion per shot. That leaves 755 million to build a new hubble and apply the refits. The original hubble cost 1.5 Billion at launch, which I presume includes launch costs, development costs and such, of which building costs would actually be pretty cheap, seeing as how we still have the plans to use in building another one.

Why? For speed?

Conventional trains routinely hit 320 km/h FOR LONG STRETCHES AND DURATIONS (not just for 10km portion out of a 700 km journey), and have gone as fast as 515 km/h in tests.

The sheer complexity of the switches (*) guarantees that the resulting network will be much less flexible than an ordinary conventional high-speed rail whose switches are of the ultra-simple time-tested conventional design.

What does speed gives you? Since the energy expenditure squares each time the speed is doubled, you soon hit a wall where the energy efficiency drops well below an aircraft.

For example, a 1200 km trip (New-York_Chicago) Speed time saved* Energy How much more than
100 12 10000 at 100 km/h
200 6 6 40000 4 times
300 4 2 90000 9 times
400 3 1 160000 16 times
500 2.4 0.6 250000 25 times
600 2 0.4 360000 36 times
700 1.71 0.29 490000 49 times
* from previous time Fucking slashcode that won't let PRE pass. Fuck it (and cowboy neal too, at the same time).

So, each time you increase speed by 100 km/h, your energy use soars so much that for saving a paltry quarter-hour, you spend 13 times more energy than needed to go at 100 km/h!!!

This is the reason french TGVs only run at 300 km/h. They are designed for 400 km/h and routinely hit 450 km/h for demos but running them at 400 km/h would be too expensive for the tiny amount if time gained.

A high-speed maglev runs at the surface, where the air resistance is waaaaay much higher than for an aircraft at 35,000 feet. So the energy expenditure per seat IS GOING TO BE HIGHER than an airplane!

Even though the speed of sound is much higher on the ground than at 60,000 feet (where Concorde used to fly), 1000 km/h maglev trains will need very long viaducts and tunnels to avoid becoming high-speed stomach wrenching roller-coaster rides.

The only way a maglev could be useful is running within an evacuated tunnel in a long journey.

In theory, the trains could run at the orbital speed of the altitude they are; energy expenditure would then be zero (all you'd need is to accelerate the train to speed, and you'd recover most of that energy by decellerating it at destination). But the costs of digging tunnels that would be so perfectly aligned, immune to geological havoc (crossing from one tectonic plate to another isn't really a walk in the park) and to keep the thing perfectly evacuated would likely be prohibitive (and maintenance guys would need to work in spacesuits...). Such money should be spent instead for a space elevator.

Putting the tube underground buys you some security and right of way. Security in that an evacuated tube would be tough to defend vs. a tunnel that isn't advertising its presence and is behind several 10s of feet of dirt.

A description of a larger scale system can be found here.

The Japanese made a couple of mistakes however. First their track switching technology is cumbersome. They literally move concrete barriers around to shove the train onto another track. Secondly, they didn't design their magnets correctly and so have had problems maintaining them. Those problems aside, the Japanese have done a first rate implementation job.

The Germans, in an attempt to circumvent the Powell and Danby patents and cut costs, chose a conventional electromagnet approach for their maglev solution. Powell and Danby had considered eletromagnets and rejected them due to inherent limitations. First, electromagnets aren't anywhere as strong as superconducting magnets so the gap between vehicle and track is much smaller. Secondly, a power loss would be catastrophic. Thirdly, the way the Germans have approached maglev using magnets to attract each other, requires active controls. The intra-magnet gap has to be maintained to very close tolerances otherwise the train gets pulled into the track or falls away from the track if it veers too far. The tolerance problem will be especially acute in seismically active locations like China and California where tracks will drift slightly on a daily basis.

Powell and Danby have kept working at maglev despite paltry American support. Their website describes several design changes to their original idea. They've designed all electronic switching equipment that makes dynamic track switching feasible. That's advantagous on a heavily traveled track that's being shared by express and local trains. They've also re-arranged their track to a monorail cum flatbed design to support dynamic switching.

Their website describes a variety of uses for maglev. Among them is a trans-continental vacuum tube that enables coast to coast travel in under an hour. The vacuum is necessary because as the train speed increases, the majority of power that's required to move the train is spent moving air out of the way. An evacuated tube makes it possible to move a train across the continent using the equivalent of 20 gallons of gas.

One hundred and fifty years ago, Lincoln authorized the construction of a transcontinental railroad. At the time, it was considered technologically impossible given the chasms and mountains that had to be crossed. Lincoln initiated the transcontinental railroad in the middle of the civil war. Part of his motivation was to demonstrate that though engaged in war, the United States was great enough to concurrently tackle a monumental engineering task.

Fifty years later, we built the Panama Canal, another technological impossibility. Finally 50 years ago, Eisenhower authorized the interstate highway system and the St. Lawrence Seaway.

Fifty years have passed since this country last undertook a major infrastructure challenge. Whether our generation steps up to the plate and makes a significant contribution to the infrastructure as our parents, grandparents and great-grandparents have done remains to be seen.

The maglev train's inventors have posted a proposal for a mach 3 train that would get you coast to coast in an hour and a half. Make the tube ultra straight and you can make the same trip in 45 minutes.

A Swedish engineering firm recently built the world's longest tunnel through hard rock for less than $10 million/mile. If the trans-continental tube came in at around that cost, it'd run $22 Billion. The trains themselves are estimated to cost around $5 million per car - a lot cheaper, and faster, than a $80 Million Gulfstream V.