On Thursday, February 28, 2013 6:00:24 PM UTC-8, Don Johnstone wrote:
We use it for free and over the years the civilian use has
improved, we no longer have position errors created by the system.

Uh, no, we do not use it for free, WE PAID FOR IT. I also seem to remember that, back in the 90s, there was an agreement that the Departments of Transportation and Commerce were to pay for specific upgrades to future blocks of satellites (now in orbit) out of their budgets, adding more civillian frequencies and localized satellite-based denial capability, in exchange the Department of Defense was going to limit the geographic scope and duration of this sort of testing within the boundaries of the US. We have now implemented such things as GPS precision approaches, ADS-B, GPS-aided positive train control systems, GPS-timed safety critical valve controls on gas pipelines, etc. Something is wrong with this picture...