Because it's not subject to the rocket equation, it would basically have the same effect on space access costs as a space elevator.
It is possible in principle for such a device to bring a vehicle up to hypersonic speeds, then regeneratively brake the same vehicle to a stop and recover a fraction of the energy.
Good reading there, but the part about the difficulties notes that it holds nuke-scale energies and states "Therefore for safety and astrodynamic reasons, launch loops are intended to be installed over an ocean near the equator, well away from habitation."
That would exclude the downtown-to-downtown feature.
the part about the difficulties notes that it holds nuke-scale energies
Nuke scale energies get dissipated in the atmosphere on a regular basis by thunderstorms. I suspect it may be possible to ensure that most of the mass burns up in the atmosphere and is dispersed.
That would exclude the downtown-to-downtown feature.
A rocketplane could "rendevous" with the electromagnetic loop at high altitude and then be accelerated and decelerated for the bulk of the cross-ocean trip, then land at an airport.
http://en.wikipedia.org/wiki/Launch_loop
Because it's not subject to the rocket equation, it would basically have the same effect on space access costs as a space elevator.
It is possible in principle for such a device to bring a vehicle up to hypersonic speeds, then regeneratively brake the same vehicle to a stop and recover a fraction of the energy.