miso@sushi.com wrote:

The free standing towers are always beefier than the tower that use
guy wires. There is a trend to free standing over guy wire in the last
decade. Guy wires are just nasty for pilots because they don't see
them until the last minute.

Agreed. But a freestanding tower, 30' on each side
is way overkill for any kind of traditional antenna
support structure. That much antenna, so low in the
valley, isn't logical. They wouldn't need that much
elevation if they wanted dishes or lenses to point
to areas in the base or in the immediate airspace.

I don't rule out an observation tower for aircraft.

I think I do. Wrong shape.

BTW, doesn't it look PLUS shaped on Google Earth?

Not at all. It looks very clearly triangular. Equilateral
triangle, one side runs East/West, the other two sides
"point" generally South. As if an arrowhead pointing South.

Triangle or plus shaped would not be a good design for
observation. Either would introduce distortion for the
viewer. Round would be the only logical and the tradional
shape (or at least a multi sided polygon with enough sides
to begin to approach roundness, like typical ATC towers).

The key here is that no other base uses such a tower...

That's, perhaps, a key. What would this base, with this
tower, do, that no other base/tower would do? All bases have
antennas and observation towers. This one suggests something else.
Something that would logically be done only at this base.
Lighter than air keeps coming to my mind.