I've been noodling with an idea for some time, and I figured I'd ask
this list for some info.

Basic idea is somebody who claimed a big section of land on a
frontier world. Or maybe it's long settled, but low pop.

I'm assuming that on a place like this you can claim a fairly large
hunk of land. Multiple km on a side.

He's quite a bit paranoid, and likes his privacy. So he worries about
getting tracked to various places on his property.

I'm assuming a satellite net for communications, S&R, weather and
some limited mapping purposes.

Anyway, I've been thinking about ways you can detect an air raft of
similar vehicle.

Anything active will be a dead giveaway that someone is looking. So
radar/lidar are mostly out.

Visual from orbit can be dealt with in various ways, (like flying
thru narrow canyons/valleys when the angle is wrong for satellites.
Ditto for flying (carefully) under the cover of trees (virgin forest
is good for that sort of thing. :-)

So visual & IR aren't too bad to deal with.

With "civilian" grade sensors (as opposed to military or ISS grade)
an air raft or larger "truck"/RV type vehicle doesn't emit enough EM
to track easily.

That leaves the CG & propulsion. What Piper called "lift & drive".
They are probably detectable to some extent with grav sensors of some
sort.

Question is, how detectable and at what range.

I'm gonna go with "speed of plot" in the end, but I'm interested in
how "reasonable" folks think my ideas are.

So, I figure that from orbit, the best you can do is "yeah, there's a
grav vehicle operating in [large area]". Tens of miles or more.
(gravity is a fairly weak force after all)

Get closer and there are probably "home on grav" missiles and the
like, but you'd have to be within a few miles.

So I'm planning on assuming that absent a tail, or IN/ISS sensors he
can in fact count on it being hard to tell where on his property he's
going if he takes some fairly simple precautions.

Anybody see a problem with that?

--
Leonard Erickson (aka shadow)
shadow at shadowgard dot com