On 06May2020 1329, Jonathan Clark wrote:
> Fundamentally, I agree. A beanstalk is a show-off project, *unless* you
> want to posit reasons to limit orbital grav traffic. Engine noise.
> Objections of the local population to sonic booms every day and night.
> A desire to not have very large ships (which do occasionally fall out of
> the sky) cruising around overhead. So *much* atmospheric grav traffic
> that it's hard to carve out ground-to-orbit (and back) corridors.
> Psycho-social or religious issues. And so on.
>
Contra-grav equipped vehicles, spaceships, etc., can simply lower
themselves so that they're under any in-use orbits (probably this would
be an altitude where there's enough air to degrade an orbit fast, but no
yet enough to cause heating, buffetting, etc.), thrust to cancel their
velocity relative to the ground, and then drift down slowly (anything up
to mach one will be fairly quiet, yet gets you to ground level in 10
minutes or less), no muss, no fuss, no sonic booms. Reaching orbit just
requires doing this in reverse.

The objections are just about all social - cheap effective gravitics
makes getting to and from orbit easy, even trivial.

--
Rupert Boleyn <xxxxxx@gmail.com>