Selective Availability was turned off in 2000 (15 years ago today) after the US government demonstrated that they could limit accuracy over any region they chos

Selective Availability was turned off in 2000 (15 years ago today) after the US government demonstrated that they could limit accuracy over any region they chose if they ever need to[1]. Most GPS receivers now implement crippled behavior at certain altitudes and speeds, but nobody assumes this to be a dependable defense. 1: "Additionally, we have demonstrated the capability to selectively deny GPS signals on a regional basis when our national security is threatened." from http://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/techops/navservices/gnss/gps/policy/presidential/ http://www.faa.gov/about/office_org/headquarters_offices/ato...