(Stuf4) wrote:
But you could only expect to hit a silo if you knew exactly where you
were launching from. That's not hard if your missiles are on land, as
most of them were in the Soviet Union. But most of the U.S. nuclear
arsenal was at sea on subs. To maintain the balance of power the U.S.
had to
come up with a way to allow those subs to surface and fix their exact
position in a matter of minutes anywhere in the world.... Hello GPS!

The problem with that is... We had no need of such a capability.
What an SSBN needs is a method of knowing it's position *without*
having to surface, or preferably even coming close to the surface. We
already had that capability with SINS, SINS/ESGM, and with ESGN.
From the point of view of an SSBN, GPS is 'nice-to-have', not 'must
have'.

GPS along with LORAN and some other things is used to calibrate the
ships inertial navigators. Once the calibration is complete, we only
need access for a few minutes to *one* of the multiple reference
standards (GPS, LORAN, BQS-3) to ensure the calibration remained
accurate. At one point the D-5 operational concept included both a
GPS mast for obtaining the calibration update prelaunch and GPS
systems in the missile itself. Both were dropped because they added
very little to total system accuracy, though the capability to obtain
discrete updates from GPS as a calibration aid were retained.

NavSTAR could easily have been named "Deathstar".

For anyone interested in a more detailed short history of GPS, here is
a link that includes the Air Force nuclear strike efforts with their
MOSAIC and 621B programs along with the Navy contributions:

http://www.aero.org/publications/cro...er2002/01.html

That link is so wrong it's laughable.

D.
--
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