Re: Plane crashes and other accidents

ChuckKuecker (
Fri, 17 Apr 1998 11:16:14 -0500 (CDT)

At 03:19 PM 4/16/98 EDT, you wrote:
>hi how would this work? Underground orbital, does that mean its in orbit, but
>underground? it seems it would work better above ground, in big tubes,
>perhaps using a vacuum pressure system to suck and push the vehicles
>(extremely light-weight vehicles, the bulk of weight coming from the cargo).

For a vehicle in orbit, whether it's above or below ground, there is no
force on it that would require rails, etc. for guidance. In reality, some
sort of maglev would probably be used to ensure the car remained centered
inside the tube.

The smaller the radius, the faster the orbital velocity. This would not make
much difference between running the tunnels underground or above ground, but
underground the least objections would be raised over right-of-way. Advances
in tunnelling technology are making this more and more attractive.

The basic system would use a linear motor to accelerate a sealed capsule in
an evacuated tube. Once orbital speed is reached, no further power is
required. At the far terminal, the energy in the capsule would be recovered
in another linear motor.

There have been airpressure systems proposed, but I believe they all suffer
from massive frictional losses when the velocity rises to a point where it
would be competitive with existing transport..

One thing that is problematical is how to transverse fault lines such as in
California. Large caverns with articulated guide tubes have been mentioned.
I read about this a few years back, but i don't remember where.

Chuck Kuecker